Category Archives: Astronomy

An international team of astronomers from the United States and the United Kingdom has made the discovery of a giant, almost symmetrical arc of galaxies by looking at absorption lines in the spectra towards quasars from the Sloan Digital Sky Survey (SDSS).

The Giant Arc: the gray contours represent the Mg II absorbers, which indicate the distribution of galaxies and galaxy clusters; the blue dots represent the background quasars; the Giant Arc is centered on this figure spanning -600 to +400 Mpc on the x-axis. Image credit: Lopez et al.

The newly-discovered arc of galaxies is located more than 9.2 billion light-years away in the constellation of Botes.

Named as the Giant Arc, it spans approximately 3.3 billion light-years in length and 330 million light-years in width.

The structure is twice the size of the striking Sloan Great Wall of galaxies and clusters that is seen in the nearby Universe.

Its discovery adds to an accumulating set of cautious challenges to the Cosmological Principle.

The growing number of large-scale structures over the size limit of what is considered theoretically viable is becoming harder to ignore, said Alexia Lopez, a Ph.D. student in the Jeremiah Horrocks Institute at the University of Central Lancashire.

According to cosmologists, the current theoretical limit is calculated to be 1.2 billion light-years, which makes the Giant Arc almost three times larger.

Can the Standard Model of cosmology account for these huge structures in the Universe as just rare flukes, or is there more to it than that?

Lopez and colleagues made the discovery by observing the intervening magnesium (Mg) II absorption systems backlit by quasars, which are remote super-luminous galaxies that emit extraordinary amounts of energy and light.

A quasar acts like a giant lamp shining a spotlight through other galaxies, with the light eventually reaching us here on Earth, Lopez said.

We can use telescopes to measure the spectra of these quasars, which essentially tells us the journey that the quasar light has been through, and in particular where the light has been absorbed.

We can locate where the quasar light has passed through galaxies by a signature Mg II doublet feature, which is a distinctive pair of absorption lines in the spectra.

From this easily identified absorption fingerprint, we can map low luminosity matter that would usually go unseen due to its faint light emitted in comparison to the quasars.

When viewed on such a large scale, we expect to see a statistically smooth distribution of matter across the Universe, based on the Cosmological Principle introduced by Einstein to make the maths easier, that the Universe is isotropic and homogeneous.

It means that the night sky, when viewed on a sufficiently large scale, should look the same, regardless of the observers locations or the directions in which they are looking.

The Giant Arc we are seeing certainly raises more questions than answers as it may expand the notion of sufficiently large. The key question is, what do we consider to be sufficiently large?

We are seeing the Giant Arc now, but in reality, the data were looking at show the Universe as it was half its lifetime ago because the light has been en route, traveling towards, us for billions of years. It was so long ago that the Universe at the time was about 1.8 times smaller than it is now.

The astronomers presented the results this month at the 238th virtual meeting of the American Astronomical Society (AAS).

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A.M. Lopez et al. 2021. A Giant Arc on the Sky. AAS 238, abstract # 111.01

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3.3-Billion-Light-Year-Long Arc of Galaxies Discovered | Astronomy - Sci-News.com

Texas A&M University astronomer Nick Suntzeff has been involved with space research for 30 years and spent 20 years in Chile, where he helped co-discover dark matter. Below, he offers his thoughts about UFOs and whether or not we are alone in the universe.

The New York Times and CNN reported a government report on "UFOs" does not provide evidence of aliens, but also doesn't rule the possibility out. USA TODAY

Q: What can we expect from the governments official UFO report?

A: I have no idea what the report will say, but I doubt they have any evidence where a UAP (Unidentified Aerial Phenomenon, previously called a UFO) is clearly resolved. For starters, have you ever noticed that UAP images and videos are usually out of focus?

In the recent videos that are now getting a lot of attention called FLIR1, Gimbal, Triangle, and GoFast, for instance, lets consider the triangular UFO. In the video you can also see other objects that are triangles. Are these sister UFOs? No. What this means is that the camera was out of focus and the camera pupil (shutter) was triangular. One person has measured the positions of the faint triangles (and one bright one) and shown that they are at the positions of the stars near the constellation Taurus and the planet Jupiter. Also, this UFO blinks in the same way a commercial aircraft does. It was taken off the coast of Los Angeles where there are lots of air traffic. It is an out-of-focus video taken with an infrared camera.

UFOs, or unidentified flying objects, have stirred our imagination for generations. Sightings of these alleged interstellar visitors to Earth have been chronicled throughout history. However, the mania for UFOs shifted into hyperdrive in 1947, when flying saucer enthusiasts believed the remains of an otherworldly spacecraft, and even the corpse of an alien, were discovered in Roswell, New Mexico.(Photo: ursatii / Getty Images)

This is one example of an explanation that fits the data. Now, why did the Navy not provide this explanation? They should have asked an astronomer before releasing the video because they could have quickly shown that this an out of focus image.

Q: So does that mean the UFOs are not real?

A: Well, you can often debunk one story, but you will then get another story and someone will say, okay, but explain this one.

In one video, a pilot said the UFO resembled a large Tic Tac mint and that it was defying the laws of physics over the ocean and moving fast. The problem here is that we dont know how far away it was. If it was high above the ocean, then the apparent motion is likely due to the airplane and not the object.

This is called parallax. You can often find answers like this, and so on.

So I am not optimistic that we will be shown extraordinary evidence where there is no natural explanation for what is seen.

Q: So you are saying that you can rule out most UFO sightings as something else and not a UFO?

A:There are often simple, but boring answers. For example, the most common UFO is the planet Venus. Once I got a phone call from an excited person who was telling me they can see a UFO right now. It is moving back and forth, and sometimes it suddenly comes closer and then moves away. I asked them if they could still see it. Yes! So I drove down to the parking lot and there was a group of people bunched together pointing up to the sky. I went over there and asked them to show me where it is. I look up there, and it is Venus. I tell then it is Venus. I look at it and it is not moving. It was twinkling a bit but otherwise, nothing unusual. As we looked, they admitted it was not moving, but I was assured that it was before I got there.

Q: Many people are convinced that these UFOs are visitors from another planet, that they have been monitoring the Earth for decades and they are real. If true, it would be perhaps the biggest story of all time. Is it possible?

A:I cant rule out we have visitors from other planets. But we need clear evidence. We need a clear photo for instance. So far, we do not have such evidence.

Note that many reports say that the UFO object was a certain size and moving at a certain speed. Now, if you dont know what the object is, you cant know how far away it is, or how big it is. Anyone who says they know the size (unless it landed and left a mark) is, well, not understanding simple optics. So once again, we need clearer proof. I have seen lots of weird things in the sky very weird things but I can always explain them.

As for intelligent life in a way it is a strange question. As the great physicist Enrico Fermi was claimed to have said, Well, where are they? That is, if there is intelligent life, why dont we see it with our telescopes, or see evidence here on Earth of visitations? Astronomers are always looking for life elsewhere in the universe.

Congress-sanctioned UFO report to be released in June 2021.(Photo: U.S. NAVY)

Q: Any shred of truth to the long-held rumors that the government has been hiding pieces of crashed UFOs and perhaps even bodies?

A: If they do, this is the best kept secret ever. Our government is not great at keeping secrets, and this one would be a doozy. No, I dont believe there is any physical evidence. I dont think intelligent civilizations could travel the thousands of light years to the earth, and then crash their spacecraft. If they can travel that distance, I seriously doubt they would be this careless.

Q: It seems like the scientific community has always been more than a little reluctant to talk about UFOs. Why is that?

A: We are not reluctant to talk about it. There are a number of astronomers actively looking for signs of intelligent life out there. It is a real field in astronomy. The problem is that one cannot get government funding to study UFOs. So those astronomers look to the private sector to do the studies. A very close friend of mine, now retired, built his own observatory and is searching for intelligent signals. He got this funded by some rich person in Silicon Valley. If there were sources of steady funding, I am sure a lot of young astronomers would take a job searching for intelligent life.

Q: Any other thoughts you may have about UFOs?

A: . This is thought experiment. We are not too far maybe 100 years or so from building mini-satellites, accelerating them up to 10% the speed of light using lasers, and sending them off to nearby stars. We could make billions of them after all, we have made billions of cell phones so far. With laser acceleration and light-weight satellites (10 grams or so), we could launch these to billions of stars. The satellite could have a radio transmitter beeping the first 10 Fibonacci numbers (numbers used to create a mathematical sequence) showing it must be artificial.

If I can imagine this future technology which is not far from what we have today, the question is, why is there no satellite from another civilization that has passed this way, and beeped at us?

The only fact we are certain of is that so far -- and we are looking hard -- it is silent out there.

Texas A&M University astronomer Nick Suntzeff has been involved with space research for 30 years and spent 20 years in Chile, where he helped co-discover dark matter.(Photo: Contributed photo)

By Keith Randall, Texas A&M University Division of Marketing & Communications

Read or Share this story: https://www.timesrecordnews.com/story/news/2021/06/17/texas-a-m-astronomer-weighs-upcoming-ufo-report/7738172002/

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Texas A&M astronomer weighs in on upcoming UFO report - Times Record News

For over five thousand years, India has been home to one of the fascinating intellectual endeavours that humankind has ever recorded. India, one of the oldest civilizations in the world, has a strong tradition of science and technology.Ancient India was a land of sages and seers as well as a land of scholars and scientists.

From the ancient Vedic ages till today, the Indians have exhibited unmatchable deep understanding and mastery over knowledge across the spectrum. The ancient Indians have left us a great treasure of knowledge, and the rational interpretation of these ideas, which has become the basis of knowledge discovery across the civilization for several ages now. From astronomy to metallurgy, mathematics to medicine, the contribution of Indians to the global knowledge discovery is enormous.

The origins of the Indian scientific endeavours can be traced to the Vedic period, over three thousand years ago. The Indian scientists have made several discoveries, becoming one of the firsts to shed light on several scientific ideas much earlier than the inception of the very same ideas in the west.In addition to discovering and recording scientific phenomenons, the Indian sages had also absorbed the scientific methods of the other culture-areas in all true spirit, thus displaying a real scientific attitude.

In fact, what interesting is, such an effort by the ancient Indians has been characterised by prolonged observations, especially with the naked eye and simple tools, at times aided by techniques that we seem to discard as crude and primitive.

A fact of great significance is that Indians produced a vast literature on different aspects of astronomy, cosmology, numerology, measures of time, development of observatories, instruments etc. The ancient Indians were also the first to study the planetary motions, design calendars, study time and the inter-disciplinary nature of many of these above aspects.

In a book titled Indian Astronomy: A Source-Book, the authors BV Subbarayappa and KV Sharma, have recorded more than 3,000 such observations and discoveries by Indian scientists, astronomers and mathematicians over thousands of years. The book intends to provide a general insight into the scientific discoveries in the field of astronomy, numerology, a measure of times and several other aspects that were accomplished in ancient India.

About 3000 verses, written by the likes of the greatest Indian astronomers and thinkers like Aryabhata, Bhaskarcharya, Brahmagupta etc have been extracted from many original sources, mainly in Sanskrit, and presented with their translations in English and notes by the authors.

Here are few of them that shed light into understanding how ancient India was the cradle for one of worlds greatest scientific discoveries.

These passages in Sanskrit brings out the authenticity of the basic characteristics of Indian astronomy as it outlines the expertise expected of an astronomer in ancient times. The below verse outlines how there was utmost importance to accuracy in ancient ages and how one had to adopt the intricate methodologies to become an astronomer. More significantly, the ancient texts gave importance to observation and mathematically developed documentation to ensure that Indian astronomers did not indulge in speculation but on empirical data.

Here is a verse that sets eligibility standards for individual practising astronomy. The ancient verses written during the Vedic ages set rules to be followed by a person before the performance of sacrifices.

The Vedas state that a certain sequence of actions should be followed at appropriate times before performing sacrifices. Hence, he who knows astronomy, which is the science specifying time, knows the sacrifices and, so, is a Vedist, reads the verse written in Rig Veda.

In his extraordinary encyclopaedia Brihat Samhita, the ancient Hindu astrologer, astronomer and polymath Varahamihira, has accounted for the detailed qualification one has to possess to become an astronomer. Varahamihira, who himself was an accomplished astronomer during the 6th century BC, was one of the first in the world to study and detail about the Sun in his treatise Surya Siddhanta.

The below verse details the conditions for an individual to be qualified as an astronomer:

The translation reads:

Among the astronomical calculations, the astronomer should be conversant with the various sub-division of time such as the yuga, year, solstice, season, month, fortnight, day and night, Yama (a period of an hour and a half), muhurta (forty-eight minutes or two ghatis), Nadi (equal to 24 minutes), prana (time required for one inhalation), truti (a small unit of time) and its further subdivisions, as well as with the ecliptic (or with geometry) that are treated of in the five Siddhantas entitled Paulisa, Romaka, Vasistha, Saura and Paitamaha. (4)

He should also be thoroughly acquainted with the reasons for the existence of the four measurement systems of the time, viz. Saura or the solar system, Savana, or the terrestrial time, i.e. the time intervening between the first rising of any given planet or star and its next rising, Nakshatra or sidereal, and Chandra or lunar, as well as for the occurrence of intercalary months and increasing and decreasing lunar days. (5)

He should also be well-versed with the calculation of the beginning and ending times of the cycle of sixty years, a yuga (a five-year period), a year, a month, a day, a horn (hour), as well as of their respective lords. (6)

He should also be capable of explaining, using arguments, the similarities and dissimilarities, and the appropriateness or otherwise of the different systems of measurement of time according to the solar and allied systems. (7)

Despite differences of opinion among the Siddhantas regarding the expiry or ending time of an Ayana (solstice), he should be capable of reconciling them by showing the agreement between correct calculation and what has been actually observed in the circle drawn on the ground using the shadow of the gnomon as well as water-instruments. (8)

He should also be well acquainted with the causes that are responsible for the different kinds of motions of the planets headed by the Sun, viz. fast, slow, southerly, northerly, towards perigee and apogee. (9)

He must be able to forecast, by calculation, the times of commencement and ending, direction, magnitude, duration, intensity and colour at the eclipses of the Sun and the Moon, as well as the conjunctions of the Moon with the five Taragrahas or non-luminous planets and the planetary conjunctions. (10)

He should also be an expert in determining accurately for each planet, its motion in yojanas, its orbit, other allied dimensions etc., all in terms of yojanas. (11)

He must be thoroughly acquainted with the Earths rotation (on its own axis around the Sun) and its revolution along the circle of constellations, its shape and such other details, the latitude of a place and its complement, the difference in the lengths of the day and night (lit. diameter of the day-circle), the carakhandas of a place, rising periods of the different signs of the zodiac at a given place, the methods of converting the length of shadow into time (in ghatis) and time into the length of the shadow and such other things, as well as those to find out the exact time in ghatis that has elapsed since sunrise or sunset at any required time from the position of the Sun or from the Ascendant, as the case may be. (12)

Even thousands of years before the Western astronomers discovered the shape of the Earth, Indian astronomers had accurately predicted Earths shape as spherical.

During Varahamihiras period, the development of astrological and astronomical sciences reached a pinnacle. In his book Paulisa Siddhanta, Varahamihira gives an exact description of not only the share of the earth, i.e., spherical but also provides its topographical study in detail.

The verse in Paulisa Siddhanta accounts, Earth is spherical and constituted of the five elements, which stands poised in the region of space as if it is an iron ball held in position in a cage of magnets. (1)

The whole earth surface is spotted by trees, mountains, cities, rivers, oceans, etc. The Meru mountain (forming the North pole) is the abode of the devas (gods). The Asuras (demons) are down below (i.e. at the South pole). (2)

Just as the reflection of the objects on the bund of a water source is upside down, so the asuras are (with respect to the devas.) The asuras, too, consider the devas to be upside down. (3)

Just as the flame of the fire, observed by men here, flares upwards, and anything is thrown up falls down towards the earth, the same upward flaring of the flame and the downward falling of a heavy object is experienced by the asuras (at the antipodal region). (4)

Below is another documentation by Varahamihira describing Earth and its close correspondence with Panchabhutas.

This sphere of Earth, made of akasa, air, fire, water and clay and thus having all the properties of the five elements, surrounded by the orbits (of the Moon, etc.), and extending up to the sphere of stars, remains in (the centre of) space. (1)

Just as a ball of iron, when placed amidst pieces of magnets, remains suspended in space, in the same manner, this globe of Earth remains in space unsupported, while itself remaining the abode of all. (2)

The third verse says Yamakoti is to the east of Lanka (which is in the middle of the Earth), and Romaka (Rome) is to the west. Siddhapura is beneath Lanka (just opposite); the Meru (mountains) is to the north, and the abode of the demons is to the south. (3)

These (four cities) are on islands. Meru is on the land, and the abode of the demons (in the south) is surrounded by water. These six places are believed to be situated transversely at a distance of one-fourth of the Earths circumference (that is 90), each from the next one. (4)

Those who are at a distance of half the Earths circumference from each other are antipodes, just as a man (standing on the bank of a river) and his reflection in the water. The sky is above all. This (globe of Earth) is beneath it. The inhabitants are on the surface of the Earth. (5)

Kamalakara, anIndianastronomerandmathematician,who lived in Varanasi in the 17th century AD, gave the first detailed account of the causes of earthquake within Earths crust. However, the European geologists took another century to publish a basic understanding of Earths interiors and the phenomenon of Earthquakes.

In his book Siddhntatattvaviveka, Kamalakara has stated that the Earths crust is hard and rocky. Explaining the process of the earthquake, he writes, a fissure occurs due to lack of strength, gases emerge forcibly, causing the Earth to quake when there would also be constant terrific noise.

Similarly, Lalla, anIndianmathematician,astronomer, andastrologer, had discovered in the 8th century AD that the Earth travelled from west to east and if anyone viewed it from the north pole star Polaris,Earthturns left, i.e., counterclockwise.

The Indian astronomers made accurate discoveries on earths rotation and direction of rotation; centuries before, European astronomers came up with such predictions explaining concepts of Earths rotation.

Lallass documentation on Earths rotation on its axis and the direction of its rotation:

The translation of Lallas work reads: The celestial sphere, at the Earths equator, is constantly carried towards the west by the Pravaha wind. To the gods (at the north pole), it appears to move (from the left) to the right and the demons (at the south pole from the right) to the left. (3).

Chaturveda Prithudaka Swami, another astronomer, known for his exemplary work on mathematical equations, explained that it is only the Earth that is regularly rotating once a day, and the sphere of the stars is fixed, causing the rising and setting of the stars and the planets.

In his book Commentaries onBrahmasphuasiddhanta, Prithudaka Swami explain the causes behind the phenomenon of days and nights.

The translation of one of his works reads: The Earths rotation had been accepted by Aryabhata also, vide his words, The Earth rotates through (an angle of) one second per one prana (of time). On account of (possible) adverse criticism by people, Bhaskara I and others explained the verse to give it a different meaning.

Aryabhata, arguably the worlds oldest astronomer, had explained the rotation of Earth on its own axis. The above work of Aryabhata is mentioned in his masterpiece Aryabhatiyam, which translated into, Rotation of the Earth also has been accepted by Acarya (Aryabhata). Note that there is a variant reading as The Earth rotates through (an angle of) one second per one prana (of time).

In his book, Aryabhata explains, Just as a man in a boat moving forward sees the stationary objects (on either side of the river) as moving backwards, so are the stationary stars seen by people at Lanka (on the equator), as moving exactly towards the west. (9)

(It so appears as if) the entire structure of the asterisms, together with the planets, moved exactly towards the west of Lanka, being constantly driven by the pro-vector wind to cause their rising and setting. (10)

The earlier texts also had reference to the direction of the earths rotation. Makkibhatta, too has discovered that the Earth rotates on its own axis from west to east.

Rig Vedic verses, written more than 5,000 ago, had estimated the dimensions of Earth. Here is a Rig Vedic verse that mentions Mother Earth and its dimensions. It is by far the oldest document to speak, even though it does not explain details about the dimensions and size of the earth.

The translation of the Rigvedic verse translated into: Oh (God) Indra, were this Earth to magnify itself tenfold (i.e., infinitely) and men who live on it multiplied day by day, then and then alone will the lauded might and glory of yours be as vast as the heavens.

In his seminal work, Varahamihira builds on assumptions of Rigvedic times and accurately estimates the circumference of the earth as 3200 yojanas. Furthermore, each Yojana is estimated to be 12-15 km, which translates into nearly 38,000 km to 45,000 km, which is almost accurate to the current estimates.

Earths circumferenceis the distance aroundEarth and it is Measured around the Equator, it is 40,075.017 km.

When situated on the equator, the Sun is visible from pole to pole at all latitudes, making the day and night equal). The middle of the Earth (the North pole is meant here) is north of Ujjain by 586 2/3 yojanas. It is north of Lanka by 800 yojanas.

Similarly, in his book Khandakhadyaka, Brahmagupta had also estimated the circumference of the Earth. The above documentation in his book suggests that he had mathematically derived an accurate measurement of Earths circumference.

The translation of Brahmaguptas work reads: Multiply 5000 by thejja of the colatitude of the place and divide the product by the trijyd. The result is the correct circumference of the Earth at that place. (6a)

Deva, another ancient astronomer, too had come up with an accurate measurement of the Earths circumference. In addition to it, Deva had also calculated the distance between Ujjain (Madhya Pradesh) and Lanka (Sri Lanka), which was nearly 200 yojanas, approximately 3,000 km.

The translation of the above reads: 3299 (yojanas) is the Earths circumference; this divided by 16 gives the distance between Lanka and Avanti (or Ujjayini.)

Similarly, Bhaskara II in his major treatise Siddhanta Siromani, had said that that the circumference of the Earth sphere is said to be 4967 yojanas.

Its diameter is 1581 1/24 yojanas. The surface area thereof is 7,85,034 square yojanas, for it is obvious that, as in the case of a spherical ball, the product of the Earths circumference and its diameter gives its surface area. (52), Bhaskara II wrote in Siddhanta Siromani.

Interestingly, Bhaskar was one of the first to provide an accurate mathematical model to derive the circumference of the Earth. According to his estimation, Earth was 4967 yojana and its diameter 1581.

As per Bhaskara II, a yojana is equal to the (distance between the two places*360)/(circumference-(difference in the latitudes of two places on the same terrestrial meridian in degrees).

In his book, Bhaskara II notes, The equatorial circumference of the earth multiplied by cos 0 and divided by R, or multiplied by 12 and divided by the hypotenuse of the right-angled triangle formed by the gnomon and the equinoctial midday shadow thereof, (hereafter called equinoctial hypotenuse), gives the circumference of the Earth parallel to the equator and passing through the locality (hereafter called the rectified circumference).

Estimating the earths circumference, Astronomer Nilakantha had accurately measured that the earths diameter is around 1050 yojans, i.e., 12,000 km.

His above work reads: The terrestrial sphere is 1050 yojanas in diameter and it stands in the sky in the centre of the celestial sphere, as the lowest point.

Here is another ancient text giving us the mathematical formulae to determine the circumference of the earth.

The above verse reads: Having fixed upon two places situated exactly north and south, determine their latitudes and the number of yojana-s between them. Then apply the rule of three: If their difference in latitudes causes the distance between the two places, how much (will the distance be) for the degrees in a circle (i.e., 360)? The result will be the circumference of the Earth. (12-13)

The next verse explains: If the difference in degrees of the two latitudes is the yojanas between them, how many will the yojanas be for 90, which is the latitude of Meru? This will give a quarter of the circumference of the Earth. (14).

Indian mathematicians first recorded the Decimal number system, which is the basis of modern mathematics today. The ancientand medievalIndianmathematical works, all composed in Sanskrit, consisted of several sutras discussing the Decimal system of numbers.

It was Indians who gavethe ingenious method of expressing all numbers by means of ten symbols the decimal system. The simplicity of the decimal notation facilitated calculation, and this system invented by the Indians made the uses of arithmetic in practical inventions much faster and easier.

In his work Aryabhatiyam, Aryabhata explains the decimal system of numbers, where the corresponding place value of a digit is always 10 times as great as the place value of the digit to its right.

The translation of Aryabhatas work, originally written in Sanskrit: Eka (units place), DaSa (tens place), Shatha (hundreds place), Sahasra (thousands place), Ayuta (ten thousand place), Niyuta (hundred thousand place), Prayuta (millions place), Koti (ten million place), Arbuda (hundred million place), and Vrnda (thousand million place) are, respectively, from place to place, every ten times the preceding. (2)

Astronomer-mathematicianSankara Varman, in the later part of the medieval era, also explained the decimal system that was enumerated by the likes of Aryabhata.

The translation of the above work reads: Eka (1), Dasa (10), Shatha (100), Sahasra (1000), Ayuta (10,000), Niyuta (or Lakh, 10s), Prayuta (10^6 ), Koti (10^7), Arbuda (10^8), Vrnda (10^9), Kharva (10^10), Nikharva (10^11), Mahapadma (10^12), Sanku (10^13), Varidhi (10^14), Antya (10^15), Madhya (10^16), Parardha (10^17) are numbers, each tenfold of the previous.

Here is a Yajurvedic verse that also cites the usage of the decimal system of numbers in the Vedic era. In addition, the Yajurvedic hymns mention the usage of the decimal value system in its ritual practises.

The translation of the hymn reads: O Agni, may these (sacrificial) bricks be my own milch-kine: one and a ten, a ten and a hundred, a hundred and a thousand, a thousand and a ten thou sand, a ten thousand and a hundred thousand, a hundred thousand and a million, a ten million, a hundred million, a thousand million, a ten thousand million, a hundred thousand million, a million-million or billion. May these bricks be mine milch-kine in yonder world and in this world.

In India, a system oftime measurementwas in place as early as in Early Vedic Era, dating 2500 BCE. There are several references to the measurement of time in sa and Upanishads.

Here is a Rigvedic hymn explaining the way time was measured in the Vedic age. The above hymn reads that the division of time in Vedic era was on the basis of Year, Months and Days.

The translation of the Rigveda hymn says: The wheel (of time) formed with twelve spokes revolves round the heavens without wearing out. O Agni! on it are 720 sons (viz. days and nights).

The above verse says time was divided into 12 spokes (hourly), with a combined 720 days and nights making it 360 calendar days.

Another Rig Vedic hymn says: The fellies (or arcs) are twelve; the wheel is one; three-(partitioned) are the axles (or hubs); but who knows it? Within it are collected 360 (spokes), which are, as it were, movable and unmovable.

According to Rig Veda, sage Dhrtavrata knew the twelve months. He also knows the month that is created, the Vedic documents reveals suggesting that the Vedic people knew and practised a sophisticated system of time consisting of 360 days, 12 months, which is almost identical to the Gregorian system of calendars which came thousands of years later and continued to be used even today.

Here is another Yajurveda prayers for hailing interstellar objects such as sun, moon, stars, responsible for formation of day and nights.

Oblation to (the intercalary month) Samsarpa, an oblation to the Moon, an oblation to the luminaries, an oblation to (the intercalary month) Malimluca, an oblation to the Sun, reads the Yajurveda verse.

Taittiriya Brahmanas also list the names of 13 months as per the Lunar system of calendar.

The names of the thirteen months: Aruna, Arunarajas, Pundarika, Visvajit, Abhijit, Ardra, Pinvamana, Anna- van, Rasa-van, Iravan, Sarvausadha, Sambhara and Mahasvan.

The Taittiriya Brahmanas also mentions the names of 24 half-months (pakshas):

The names of the 24 half-months are: Pavitra, Pavisyan, Puta, Medhya, YaSas, Yasasvan, Ayus, Amrta, Jiva, Jivisyan, Sarga, Loka, Sahasvan, Sahlyan, Ojasvan, Sahamana, Jayan, Abhijayan, Sudravina, Dravinodas, Ardrapavitra, Harikesa, Moda and Pramoda.

The Satapatha Brahmanas also mentions the Lunar year consisting of 354 days.

Verily, they who perform the Full and New Moon sacrifices run a race. One ought to perform it for fifteen years. But, in these fifteen years, there are three hundred and sixty full moons and new moons. And, there are, in a year, three hundred and sixty nights; it is the nights he thus gains. (10), reads the Satapatha Brahmana.

Further, He should then sacrifice for another fifteen years. In these fifteen years, there are three hundred and sixty full moons and new moons, and there are in a year three hundred and sixty days; it is the days he thus gains, and the year itself he thus gains. (11)

The authors have documented more than 3,000 verses in their magnum opus, that shed light on the major scientific accomplishments by Indians hundreds of years even before their western counterparts had conceptualised these ideas.

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Earth, space, time, and more: Read how Indian scholars had recorded astronomical facts centuries before they were discovered by Westerns - OpIndia

A team of astronomers studying distant exploding stars has found a way to tighten up the way the distance to them is measured and in doing so, tighten up measurements of how the Universe is expanding.

This kind of supernova is called a Type Ia. These occur when a small, dense white dwarf accumulates matter on its surface, eventually gathering so much matter the entire star undergoes nuclear fusion. The release of energy is absolutely colossal, equivalent to billions of times the Sun's output.

This is important for two reasons. Well, lots of reasons, but two we're concerned with here. One is that quantum mechanics makes the rules here, and all these stars explode when they reach a certain mass (about 1.4 times the Sun's mass), and that means they explode with about the same energy. That in turn means that if we see one close by or far away, we can measure its distance simply by determining how bright it got.

The other is that they are so bright they can be seen at vast distances, billions of light years away. The Universe is expanding, and more distant objects are moving away more rapidly. If we can measure these Type Ia supernovae with great accuracy we can determine how the Universe is expanding.

And, in fact, this has been done. In 1998 two different teams published results showing that the Universe is not just expanding but accelerating, expanding faster every day. It's not clear what is causing this, but we call it dark energy, and figuring out what this stuff really is made of is a major goal in astrophysics after all, we're talking the fate of the Universe here.

The problem is that not all Type Ias explode in exactly the same way. But this can be compensated for. As an example, some give off more energy than others, and in general those take longer to reach their peak brightness and fade. So, if you measure how long it takes to brighten and fade, you can determine its peak brightness, and then use that to get the distance.

This was what led to the breakthrough in 1998. But even so, there is still some wiggle room in the way they explode, some uncertainty in their brightness that means we still have some uncertainty in our measurements of how rapidly the Universe is expanding.

That's what the new work looks at. They found a new method to determine the distance to these exploding stars, and published two papers about it; the first deals with developing the method, and the second implementing it.

What they did is complex and clever. They looked at over 170 supernovae, taking spectra of them around the time of maximum brightness (in general they take a couple of weeks to get to their brightest, and then fade over many months). A spectrum shows how bright an object is in different wavelengths, which you can think of as colors; in this case many hundreds of colors. Different elements absorb and emit light at different wavelengths, which in turn can be used as diagnostics for the supernova about its temperature, speed, density, and so forth.

Instead of just looking at one characteristic, like how long it takes to brighten and fade, they could look at many, and found that overall the 173 supernovae they observed look remarkably similar near maximum brightness. They did find that some individual lines (astronomy speak for wavelengths where elements absorb or emit light) change from supernova to supernova, but if they looked at the light coming from between major lines (they literally called this the Reading Between The Lines method) all the supernovae looked incredibly similar.

This allowed them to create a computer model that compensated for differences between the individual supernovae due to external variations (like if one happened to be embedded in a dust cloud) which meant that any differences from one supernova to another must be due to something intrinsic, like its chemical composition or other physical factors.

They employed machine learning to find "supernova twins," where two different supernovae spectra had very similar spectra. Using those as a baseline they could then explore how the spectra differed and discover that in the end, only three factors affected how the brightness changes from supernova to supernova the light from calcium and silicon, and how rapidly the supernova debris expands.

By modeling these three factors they could then compensate for them, allowing them to more accurately predict just how bright a supernova gets. What they found is that their method is a significant improvement over the older one (using how long it takes the supernova to brighten and fade), and they are able to drop the distance uncertainty to only about 3%.

This is important! The better our distance measurement gets, the better we can measure the effects of dark energy on the cosmic expansion. As bigger telescopes come online in the next few years, more supernovae will be observed farther away. By applying this method, hopefully, those far distant explosions can be used even more accurately than before to understand what the Universe is doing.

It's an amazing thing that astronomers are trying to figure out how the Universe itself behaves, and even to understand its fate. But we are and we're getting better at it all the time.

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How far away are supernovae? Astronomers find a way to tighten measurements - SYFY WIRE

Using a new observatory, a team of Chinese astronomers have found over a dozen sources of ultra-high energy cosmic rays. And those sources arent from some distant, exotic corner of the cosmos. They come from our own backyard.

Ultra-high energy cosmic rays (UHECRs) arepretty energetic, typically millions of times more energetic than our most powerful particle accelerators. They are also relatively rare, and so astronomers have had a hard time pinpointing their origins.

But a team of Chinese scientists led by Institute of High Energy Physics (IHEP) under the Chinese Academy of Sciences dug deep into the origins of UHECRs using the recently-built Large High Altitude Air Shower Observatory (LHAASO). LHAASO is currently under construction in Daocheng in southwest Chinas Sichuan Province, but the astronomers were able to use the completed half of the instrument for an 11-month observation run.

They found a dozen sources of UHECRs, as well as some high-energy photons, including one with an energy of 1.4 Peta-electron volts (quadrillion electron-volts or PeV), the most energetic photon ever observed.

All those sources sit within the Milky Way.

These findings overturn our traditional understanding of the Milky Way and open up an era of UHE gamma astronomy. These observations will prompt us to rethink the mechanism by which high-energy particles are generated and propagated in the Milky Way, said Cao Zhen, chief scientist of LHAASO.

In addition, these observations will encourage us to explore more deeply violent celestial phenomena and their physical processes, as well as to test basic physical laws under extreme conditions, Cao said.

The sources of the UHECRs include a variety of natures own particle accelerators: newly-formed giant stars, supernovae explosions, massive star clusters, pulsar wind nebulae, and more.

The entire facility of LHAASO will be completed in 2021. With the completion of LHAASO and continuous data accumulation, we can anticipate finding an unexplored UHE universe full of surprising phenomena, He Huihai with the IHEP added.

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Astronomers Have Tracked Down the Source of High Energy Cosmic Rays to Regions Within the Milky Way Itself - Universe Today

The concept design of the LUVOIR space telescope would place it at the L2 Lagrange point, where a ... [+] 15.1-meter primary mirror would unfold and begin observing the Universe, bringing us untold scientific and astronomical riches. From the distant Universe to the smallest particles to the lowest temperatures and more, the frontiers of fundamental science are indispensable for enabling tomorrow's applied science frontiers.

When it comes to uncovering the ultimate truths about reality, we can only reap what we sow. Without a cutting-edge particle collider like the Large Hadron Collider at CERN, we would never have discovered the Higgs Boson. Without the incredible sensitivities achieved by gravitational wave detectors such as LIGO and Virgo, we never would have directly detected gravitational waves. And without a revolutionary space telescope like Hubble, the overwhelming majority of the Universe which has since been revealed to us in exquisite detail would have remained obscure.

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In our quest to understand the Universe around us, we always seek to extract the maximum amount of science possible from whatever tools we choose to build. Once every 10 years, the entire astrophysics community gets together to submit their recommendations for which projects would be of the greatest scientific benefit to the field: part of a decadal survey conducted by the National Academies. These surveys have brought us some of the most iconic missions in history, and have helped advance science like nothing else ever has. In just a few months, theyll release their decision on recommendations for the four astrophysics missions that made it as finalists. With the results yet to be revealed, theres one proposed observatory that everyone should know about: LUVOIR. If youve ever dreamed about knowing the answers to the biggest questions of all, this is the one telescope that we absolutely must build. Heres why.

The Hubble Space Telescope, as imaged during its last and final servicing mission. Although it ... [+] hasn't been serviced in over a decade, Hubble continues to be humanity's flagship ultraviolet, optical, and near-infrared telescope in space, and has taken us beyond the limits of any other space-based or ground-based observatory.

For the past 31 years, NASAs Hubble has truly showcased for us what a cutting edge, space-based observatory is capable of. Far above the atmosphere of Earth, Hubble:

In fact, the limiting factor to Hubbles equipment the reason it cant observe at wavelengths longer than about 2 microns, or about three times as long as the limit of human vision is because it gets heated by the Sun. Just as infrared cameras reveal heat sources, the inside of Hubble is too warm to observe at mid-and-far infrared wavelengths.

The visible light (L) and infrared (R) wavelength views of the same object: the Pillars of Creation. ... [+] Note how much more transparent the gas-and-dust is to infrared radiation, and how that affects the background and interior stars that we can detect. These infrared views are limited by the temperature of Hubble: without a cooler telescope, it cannot measure longer-wavelength light.

Hubbles other major limitation is its narrow field-of-view. Even with the most advanced camera ever installed on it, the Advanced Camera for Surveys/Wide Field Camera 3, it can only achieve resolutions of approximately 8 megapixels. When you take into account the mirror size and focal length of Hubble optical properties that are second nature to astronomers it can resolve objects down to angular resolutions of just 0.04 arc-seconds, or just one-ninety-thousandth of a degree. If you put the Hubble Space Telescope in New York, it could resolve two separate fireflies in Tokyo if they were separated by merely 3 meters (10 feet).

This makes Hubble outstanding at taking deep, high-resolution observations in the ultraviolet, optical, and near-infrared, over small fields-of-view. Various observing campaigns, like the Hubble Deep Field, Ultra Deep Field, and eXtreme Deep Fields, have taken advantage of these capabilities to reveal what lies out there in the abyss of deep space: thousands upon thousands of galaxies in tiny regions of space that cover mere fractions of a millionth of the sky.

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The Hubble eXtreme Deep Field (XDF) may have observed a region of sky just 1/32,000,000th of the ... [+] total, but was able to uncover a whopping 5,500 galaxies within it: an estimated 10% of the total number of galaxies actually contained in this pencil-beam-style slice. The remaining 90% of galaxies are either too faint or too red or too obscured for Hubble to reveal.

Yet even at the full extent of its capabilities even with the equivalent of a month of continuous observing Hubble can still only see an estimated ~10% of the galaxies that are out there. Most of them are some combination of:

to be seen by Hubble. Moreover, even the majority of galaxies that are revealed are barely more than a few points, as Hubble is too small in size, with too little resolving power, to reveal additional details. In many ways, Hubble represents the greatest astronomical endeavor ever undertaken by our civilization, but its also fundamentally limited.

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Over the coming decade, beginning later this year, two additional space-based NASA observatories will launch: the James Webb Space Telescope, which is larger, cooler, and can work with much longer wavelengths than Hubble can, and the Nancy Roman Telescope, which is very similar to Hubble except with wide-field capabilities and much more powerful, state-of-the-art cameras.

The Hubble Ultra-Deep Field, shown in blue, is currently the largest, deepest long-exposure campaign ... [+] undertaken by humanity. For the same amount of observing time, the Nancy Grace Roman Telescope will be able to image the orange area to the exact same depth, revealing over 100 times as many objects as are present in the comparable Hubble image.

These observatories will begin to tackle some of the questions that Hubble cannot answer. With its enormous sunshade, its location far beyond both the Earth and the Moon, its on-board active coolant, and its enormous, gold-coated 6.5-meter primary mirror, James Webb will surpass Hubble on many fronts. Instead of ~2 microns, it can observe wavelengths out to ~30 microns, revealing an enormous suite of science details that Hubble cannot. From the earliest stars and farthest galaxies to details about planet formation and the atmospheric composition of the closest Earth-like planets around the smallest stars, this observatory is truly the next leap forward for space-based astronomy.

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The Nancy Roman Telescope, on the other hand, will go broad, wide, and just as deep as Hubble. With its wide-field views, each observation will collect 300 megapixels of data compared to Hubble 8, enabling large, deep, wide-field surveys to be done in just a tiny fraction of the time. Roman will shine brightest when it comes to observing projects like the ones that created the Hubble Frontier Fields or that imaged the Andromeda galaxy. Instead of months of observing time, Roman could do it in mere hours.

The streaks and arcs present in Abell 370, a distant galaxy cluster some 5-6 billion light years ... [+] away, are some of the strongest evidence for gravitational lensing and dark matter that we have. The lensed galaxies are even more distant, with some of them making up the most distant galaxies ever seen. This cluster, part of the Hubble Frontier Fields program, could be imaged in less than 1% of the time it took Hubble to do it with LUVOIR.

But even with these advances, there are still questions that we want answers to big, important, even existential questions that will go unanswered. Even with Webb and Roman, most of the galaxies in the Universe, even in a tiny, narrow region of space, will remain elusive. Most of the galaxies that we do see will still, unfortunately, simply be a few pixels across, with barely discernible structure. And, perhaps most importantly, they wont have the ultimate capabilities of a space-based observatory: the ability to directly image Earth-sized planets around Sun-like stars, and to identify which ones might not only have signatures for life, but might actually be inhabited.

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There is one telescope thats been designed that could accomplish all of these, and its one of the four finalists to determine what NASAs plan for astrophysics flagship missions will be for the 2030s: LUVOIR.

The Hubble Space Telescope (left) is our greatest flagship observatory in astrophysics history, but ... [+] is much smaller and less powerful than the upcoming James Webb (center). However, in order to get the resolution and contrast necessary to determine the atmospheric contents of an Earth-sized planet around a M-class star like TOI 700 located ~100 light-years away, a more powerful telescope, such as the proposed LUVOIR observatory, will be necessary.

What is LUVOIR?

Its the Large UltraViolet, Optical, and InfraRed telescope. Basically, you should imagine a version of the largest functional ground-based telescopes we have operating today telescopes like the ones at Keck Observatory or the Gran Telescopio CANARIAS equipping it with the greatest instruments that modern technology can offer, and launching it into space. Thats LUVOIR.

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In terms of what LUVOIR will bring us, its hard to overstate just how powerful an observatory like this would be. Sure, its technical specifications are impressive, but whats really impressive is how it will help answer some of the biggest questions we have about the Universe today.

Is 'Planet Nine' real? The science is still uncertain. But if it does exist, most ground-based ... [+] telescopes or even current/future space-based telescopes will be barely able to image a single pixel's worth of it. But LUVOIR will be able, even at its great distance, to reveal intricate structure on the surface of the world.

1.) Are there any inhabited planets nearby? Note the use of that word: inhabited. Were not talking about looking for potentially habitable worlds, nor worlds with bio-hints or bio-signatures, nor words that might be capable of someday being home to humans. Were talking about the big one: finding out if the nearest Earth-like planets actually have life on them. And were not talking about one or two nearby planets, but dozens, and potentially even hundreds.

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Well not only be able to directly image these worlds with LUVOIR, well be able to determine:

As LUVOIR scientist Jason Tumlinson said, it could explore dozens or Earth-like planets and assay their atmospheres. Detecting an exoplanet showing signs of life would be a discovery on the level of Newton, Einstein, Darwin, quantum mechanics, Hubbles expansion - you name it. LUVOIR is the first telescope designed from the beginning for this revolutionary purpose.

A simulated view of the same part of the sky, with the same observing time, with both Hubble (L) and ... [+] the initial architecture of LUVOIR (R). The difference is breathtaking, and represents what civilization-scale science can deliver.

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2.) The ability to finally reveal almost all of the objects that Hubble, Webb, and Roman will overlook. With LUVOIRs size, optical capabilities, and novel instrumentation, it will surpass all previous limits in terms of what it can discover. The jump from Hubble, at the absolute limit of the faintest objects in the eXtreme Deep Field, to LUVOIR will reveal objects a whopping 40 times fainter than we can presently see. Thats the same leap from large, ground-based telescopes to Hubble, or from a 30-second exposure with a 2-meter telescope to an all-night exposure with the largest telescopes presently in the world.

Basically, if youre looking for objects that are faint, far away, small, or otherwise difficult to characterize, LUVOIR will not only find it if you know where to look, but it can tell you far more about its details than any other tool.

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A simulated image of what Hubble would see for a distant, star-forming galaxy (L), versus what a ... [+] 10-15 meter class telescope like LUVOIR would see for the same galaxy (R). The astronomical power of such an observatory would be unmatched by anything else: on Earth or in space. LUVOIR, as proposed, could resolve structures as small as ~1,000 light-years in size for every single galaxy in the Universe.

3.) What does any galaxy in the Universe, in detail, look like? Imagine being able to point your telescope at any galaxy in the Universe an object typically around 100,000 light-years across and no matter how far away it is, still being able to see features in it as small as ~300 light-years across. For a galaxy the size of the Milky Way, no matter how distant it is from us, LUVOIR would show it as at least 400 pixels across, containing over 120,000 pixels of useful, luminous information in every frame.

The same galaxy, if it were imaged with Hubble in the same amount of time, would contain only 0.06% of the information contained in a LUVOIR image, with vastly inferior resolution and light-gathering power. We could learn:

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and so much more. From objects within our Solar System to exoplanets, stars, galaxies, and the largest cosmic structures of all, LUVOIR would answer the biggest questions we have about our Universe. All we have to do, to make our dreams of knowing whats out there in the Universe come true, is choose to build it.

Lynx, as a next-generation X-ray observatory, will serve as the ultimate complement to optical ... [+] 30-meter class telescopes being built on the ground and observatories like James Webb and WFIRST in space. Lynx will have to compete with the ESA's Athena mission, which has a superior field-of-view, but Lynx truly shines in terms of angular resolution and sensitivity. Both observatories could revolutionize and extend our view of the X-ray Universe.

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We owe the greatest space-based observatories in history to decadal surveys conducted in the recent past. Theyve brought us telescopes like Hubble, Spitzer (infrared), Chandra (X-rays), and will be bringing us the upcoming Webb and Roman telescopes as well. The current decadal survey, which charts the course for astronomys future in space, has four excellent options, but only one has the power to reveal whether dozens or even hundreds of potentially habitable worlds are, in fact, inhabited: LUVOIR. Its the one observatory that could revolutionize astronomy over and over again, possibly for as long as the remainder of the 21st century.

But the ultimate hope is that we wont just build LUVOIR the best of the present options but an array of observatories, one after the other, that will all cover different wavelengths and work to complement one another. Origins, a far-infrared telescope, is ideal for measuring details about planets and stars still in the process of forming. Lynx, an X-ray telescope, could reveal details about black holes, neutron stars, and colliding galaxies that nothing else can see. Even HabEx, an exoplanet-optimized mission inferior to LUVOIR in every way, could launch on a much shorter timescale, making it an attractive option.

As the head of NASAs astrophysics division, Paul Hertz, put it, I want all of these missions to fly. I think we should do them all; the decadal survey should tell me which one to do first.

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While HabEx will be a quality all-purpose astronomical observatory, promising much good science ... [+] within our Solar System and of the distant Universe, its true power will be to image and characterize Earth-like worlds around Sun-like stars, which it should be able to do for up to hundreds of planets close to our own Solar System. It still won't have the capabilities of LUVOIR, however.

When the National Academies release their recommendations in just a few weeks, the great hope of astronomers is that at least three of these missions will be chosen to move forward, with LUVOIR, the most powerful and ambitious space-based observatory ever proposed, as the top choice. If we want definitive answers to the biggest questions of all, it takes a big effort and a substantial investment. Considering that the reward is learning that theres life on that planet, orbiting another star, right over there, its clear that LUVOIR is the one telescope we must all join together to build.

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Astronomers To NASA: Please, Build This Telescope! - Forbes

Astronomy tends to have a timeless feel to it. Stars take millions of years to be born, a given galaxy will look exactly the same today as it did at the height of the Maya empire, even the constellations in the sky look pretty much the same as they did when Indigenous Australians started weaving their stories about them so very long ago in human terms.

Sometimes, though, things happen on a much faster timescale. The Stingray Nebula can lay claim to two such rapid events: It probably only started glowing about 40 years ago, and it faded substantially over just twenty years of that time!

The Stingray Nebula technically called Henize 3-1357 is what we call a planetary nebula, gas ejected by a star similar to the Sun as it dies. When such a star runs out of nuclear fuel in its core to fuse, the outer layers swell up and the star becomes a red giant. It then starts to shed the gas making up those outer layers, blowing a wind of material into space.

A lot of gas is blown off this way, so much so that deeper and deeper layers of the star get exposed. Eventually what remains is the star's core, a hot, dense white dwarf, which blasts out ultraviolet light and causes the surrounding gas to glow. The shapes that gas forms can be very strange as winds blown later catch up with and slam into slower material ejected earlier, for example. Magnetic fields, stellar spin, binary companions, and more can all sculpt the nebula into fantastic shapes.

The Stingray Nebula surrounds the star SAO 244567, what's called an asymptotic giant branch star. This means that it's already been a red giant for a while, and is well on its way to shedding its final outer layers. It obviously has been for some time, since the nebula exists, and given measurements of the gas itself (how it's expanding away from the star) it's likely SAO 244567 has been belching out gas for a thousand years or so.

In the late 1980s or early '90s something changed, though. The star started getting hotter... a lot hotter. It went from about 21,000 C in 1980 (much hotter than the Sun's 5500) to a face-melting 60,000 by 2002. At the same time it shrank in size this was determined by carefully measuring spectra taken of its light. Astronomers think that it had what's called a late thermal pulse, where gas under incredible pressure in a shell around its core underwent furious rates of fusion, heating the star up.

This extra light zapped the gas already blown out by the star, lighting it up, causing it glow literally like a neon sign. That is, electrons in the gas atoms jumped up in energy levels, then emitted light when they dropped back down. That's when it would've first been visible from Earth, making it the youngest planetary nebula ever seen.

But then the star started to settle down. By 2015 the temperature had dropped to 50,000 and the star swelled back up again.

What all this means to the nebula is that between 1996 and 2016 the gas faded considerably.

As you can see, it looks a lot different in the after shot than the earlier one. To be clear, the structure of the nebula is probably almost exactly the same; that hasn't changed much at all. What has changed is that it's faded, and in some places it's faded a lot.

For example, the outer lobes forming that broad and thick X are gone in the later image. Those have squiggly filaments of gas in them that gave the Stingray its name, but now they're too faint to see. Both images are color-coded the same way; blue light is from oxygen, green from hydrogen, and red from nitrogen. When hit by UV light they respond differently. For example, oxygen fades rapidly, even more so where the gas is dense. The lobes and inner region are heavy with oxygen and have faded the most, in some places by a factor of 900.

This fading does allow astronomers to probe the structure and nature of the nebula; it's possible to determine things like the gas density and temperature, and what exactly it's doing. Sometimes, for example, some gas glows as it slams into other gas, but in this case it looks like everything in the nebula depends on the star to glow.

So what's the fate of this nebula? It may very well continue to fade, even so much Hubble won't be able to see it. However, once the outer layers are completely blown off and the white dwarf is revealed, it will likely light up once again. That may not be for decades or even centuries, though.

Our own Sun will likely go through similar paroxysms when it's in a similar stage, about 7 billion or so years from now. Most likely our future planetary nebula it won't have such a cool shape with all that structure, but it may very well get brighter and dimmer over time, until the Sun blows off its envelope and becomes a white dwarf.

When we study planetary nebulae like the Stingray we learn more about or own distant future. And it amazes me to think that after 11+ billion years of life, the Sun will do this as well, possibly changing significantly over just a few years after all those eons.

Will future astronomers half a galaxy away oooo and ahhhh over its behavior? Who can say. But it's nice to know that even in stellar death there is awe and beauty.

Read the rest here:

The rise and rapid fall of the Stingray Nebula - SYFY WIRE

A view of the telescope domes on the roof of the Vatican Observatory, at the Apostolic Palace in Castel Gandolfo, in 2015. Andreas Solaro/AFP via Getty Images hide caption

A view of the telescope domes on the roof of the Vatican Observatory, at the Apostolic Palace in Castel Gandolfo, in 2015.

CASTEL GANDOLFO, Italy At a time of growing diffidence toward some new scientific discoveries, the one and only Vatican institution that does scientific research recently launched a campaign to promote dialogue between faith and science.

It's the Vatican Observatory, located on the grounds of the papal summer residence in Castel Gandolfo, a medieval town in Alban Hills 15 miles southeast of Rome.

The director, Brother Guy Consolmagno, is giving this reporter a guided tour of the grounds. We drive along a cypress-lined road, admiring majestic gardens and olive groves nestled near the remains of a palace of the Roman Emperor Domitian, before reaching a field with farmworkers and animals.

"This is the end that has the papal farm, so you can see the cows the papal milk comes from," Consolmagno says as he points out the working farm that provides the pope at the Vatican with vegetable and dairy products.

(Pope Francis, known for his frugality and habit of not taking vacations, decided not to use the papal summer villa, which he considers too luxurious. But he ordered the estate become a museum open to the public.)

For most of its history, the Catholic Church rejected scientific findings that conflicted with its doctrine. During the Inquisition, it even persecuted scientists such as Galileo Galilei.

In the Middle Ages, it became apparent that the Julian calendar, named for Julius Caesar and established in 46 B.C., had accumulated numerous errors. But it wasn't until 1582 that the Vatican Observatory was born with the reform of the Gregorian calendar (named for Pope Gregory XIII) that, based on observation of the stars, established fixed dates for religious festivities.

Consolmagno takes pains to rebut the anti-science image of the Catholic Church. He cites the 19th century Italian priest Angelo Secchi as a pioneer in astronomy and the 20th century Belgian priest Georges Lematre, known as "father of the Big Bang theory," which holds that the universe began in a cataclysmic explosion of a small, primeval superatom.

Astronomical text books in Latin are displayed at the Vatican Observatory. Sylvia Poggioli/NPR hide caption

Astronomical text books in Latin are displayed at the Vatican Observatory.

Run by Jesuits, the Observatory moved to this bucolic setting in the 1930s, when light pollution in Rome obstructed celestial observation.

One domed building in the papal gardens houses a huge telescope dating from 1891. It's called Carte du Ciel map of the sky and it stands under a curved ceiling that slides open. Consolmagno says, "It was one of about 18 identical telescopes that were set up around the world to photograph the sky, and every national observatory was given its own piece of sky to photograph." He adds, it was "one of the first international projects of astronomy."

A native of Detroit, Consolmagno studied physics at the Massachusetts Institute of Technology, volunteered with the Peace Corps in Africa and taught physics before becoming a Jesuit brother in his 40s. He has been at the Observatory for three decades. His passion for astronomy started with a childhood love of science fiction.

"I love the kind of science fiction that gives you that sense of wonder, that reminds you at the end of the day why we dream of being able to go into space," Consolmagno says.

A passionate Star Wars fan, he tells this reporter proudly, "even Obi-Wan Kenobi came to visit" the Observatory, pointing to the signature of actor Alec Guinness, who played the role in the original movie trilogy, in a visitor's book from 1958.

Top scientists teach at the Observatory's summer school. And scientists and space industry leaders have come for a United Nations-sponsored conference on the ethics and peaceful uses of outer space. It cooperates with NASA on several space missions and it operates a modern telescope in partnership with the University of Arizona.

Left: A visitors' book signed by actor Alec Guinness in 1958. Right: A photo of a prelate decades ago reclining to view the telescope. Sylvia Poggioli/NPR hide caption

Left: A visitors' book signed by actor Alec Guinness in 1958. Right: A photo of a prelate decades ago reclining to view the telescope.

"But where we still need to work is with the rest of the world," says the Observatory director, "the people in the pews, especially nowadays. There are too many people in the pews who think you have to choose between science and faith."

To reach those people, the Observatory recently launched a new website and podcasts exploring issues such as meteorites hitting the Earth or how to live on the moon.

And an online store sells merch hoodies, caps, tote bags and posters of the Milky Way.

In just a few months, says the director, visitors to the website have doubled.

As to how the faith-versus-science culture wars can be resolved, Consolmagno says what's most important is that he wears a collar he is a devoutly religious person who also considers himself an "orthodox scientist." "That fact alone shatters the stereotypes," he says.

Another American at the Observatory shattering stereotypes is Brother Robert Macke, curator of the collection of meteorites rocks formed in the early days of the solar system.

Holding a dark rock a few inches long, he says it was formed 4.5 billion years ago providing clues on how the solar system was formed.

"In order to understand the natural world," he says, "you have to study the natural world. You cannot just simply close your eyes and ignore it or pretend that it is other than it is. You have to study it and you have to come to appreciate it."

Consolmagno asked how the study of the stars interacts with his faith says astronomy doesn't provide answers to theological questions, and scripture doesn't explain science. "But the astronomy is the place where I interact with the Creator of the universe, where God sets up the puzzles and we have a lot of fun solving them together," the director says.

And he believes the recent dark period of the pandemic has weakened the arguments of those who are skeptical of science.

"Because people can see science in action, science doesn't have all the answers," he says. "And yet science is still with all of its mistakes and with all of its stumbling is still better than no science."

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The Vatican's Space Observatory Wants To See Stars And Faith Align - NPR

Galactic mergers like those that formed the Milky Way are violent, high-energy events that can be difficult to study. But these collisions determine the shape and composition of galaxies and trigger the formation of stars and new black holes, so untangling how they play out helps scientists understand the forces that shape the universe.

A recent analysis of a super-bright region of the sky 800 million light years from Earth reveals a merger involving three different types of galaxies, including two that likely contain supermassive black holes called active galactic nuclei (AGN).

This new finding was led by University of Maryland astronomy graduate student Jonathan Williams, who is scheduled to present the analysis of this three-galaxy system today at the 238th meeting of the American Astronomical Society.

In addition to providing insight into what happens when galaxies collide, the finding provides a rare glimpse into a merger involving at least one, and possibly two, AGN. In recent years, astronomers have been able to observe black hole mergers with increasing frequency. But most often, such observations have involved smaller black holes, not the supermassive AGN found at the center of galaxies.

This find can reveal details about how active galaxies might be triggered and serve as a guide to understanding how supermassive black holes might come together and merge, said UMD Astronomy Professor Richard Mushotzky, a co-author of the study.

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UMD Astronomer Spots Triple Galaxy Merger That Sheds Light on Black Hole, Galaxy Formation - Maryland Today

For the first time astronomers have observed waves of magnetic energy, known as Alfvn waves, in the photosphere of the sun. This discovery may help explain why the solar corona is so much hotter than the surface.

The sun is made of plasma, and like any plasma it should support Alfvn waves. These are waves in a plasma where the ions move in response to tension from a magnetic field. First predicted over 50 years ago, astronomers had until now had been unable to see them in the sun. But recent observations of the suns photosphere the lowest layer of its atmosphere and the region that releases the light that we can see have finally found them.

Magnetic fields in the sun can bundle together, forming long structures called flux tubes. These flux tubes can drive the formation of Alfvn waves. A team of researchers, led by Dr. Marco Stangalini at Italian Space Agency (ASI,Italy) with scientists from seven other research institutes and universities, including Queen Marys Dr. David Tsiklauri and Ph.D. student Callum Boocock, used the European Space Agencys IBIS to carefully monitor the suns photosphere.

Despite previous claims, Alfvn waves had never conclusively been found on the sun before.

The researchers validated their observations with the aid of magnetohydrodynamic (MHD) simulations, which are computer simulations of the complex plasma physics operating at the suns surface.

Callum Boocock, a Ph.D. student at Queen Marys School of Physics and Astronomy, said: The observations of torsional Alfven waves made by Marco and his team were remarkably similar to the behavior seen in our MHD simulations, demonstrating the importance of these simulations for discovering and explaining wave generation mechanisms.

The finding provides a crucial step to understanding why the outer solar atmosphere, the corona, has a temperature a million degrees hotter than the surface. Something much be transporting energy from the photosphere to the corona, and these Alfvn waves may be the culprit.

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Astronomers Confirm the Existence of Magnetic Waves in the Suns Photosphere - Universe Today