Daily Archives: May 24, 2020

This is an artist's impression of the Wolfe Disk, a massive rotating disk galaxy in the early universe.

A bright yellow "twist" near the center of this image shows where a planet may be forming around the AB Aurigae star. The image was captured by the European Southern Observatory's Very Large Telescope.

This artist's illustration shows the orbits of two stars and an invisible black hole 1,000 light-years from Earth. This system includes one star (small orbit seen in blue) orbiting a newly discovered black hole (orbit in red), as well as a third star in a wider orbit (also in blue).

This illustration shows a star's core, known as a white dwarf, pulled into orbit around a black hole. During each orbit, the black hole rips off more material from the star and pulls it into a glowing disk of material around the black hole. Before its encounter with the black hole, the star was a red giant in the last stages of stellar evolution.

This artist's illustration shows the collision of two 125-mile-wide icy, dusty bodies orbiting the bright star Fomalhaut, located 25 light-years away. The observation of the aftermath of this collision was once thought to be an exoplanet.

This is an artist's impression of the interstellar comet 2I/Borisov as it travels through our solar system. New observations detected carbon monixide in the cometary tail as the sun heated the comet.

This rosette pattern is the orbit of a star, called S2, around the supermassive black hole at the center of our Milky Way galaxy.

This is an artist's illustration of SN2016aps, which astronomers believe is the brightest supernova ever observed.

This is an artist's illustration of a brown dwarf, or a "failed star" object, and its magnetic field. The brown dwarf's atmosphere and magnetic field rotate at different speeds, which allowed astronomers to determine wind speed on the object.

This artist's illustration shows an intermediate-mass black hole tearing into a star.

This is an artist's impression of a large star known as HD74423 and its much smaller red dwarf companion in a binary star system. The large star appears to pulsate on one side only, and it's being distorted by the gravitational pull of its companion star into a teardrop shape.

This is an artist's impression of two white dwarfs in the process of merging. While astronomers expected that this might cause a supernova, they have found an instance of two white dwarf stars that survived merging.

A combination of space and ground-based telescopes have found evidence for the biggest explosion seen in the universe. The explosion was created by a black hole located in the Ophiuchus cluster's central galaxy, which has blasted out jets and carved a large cavity in the surrounding hot gas.

The red supergiant star Betelgeuse, in the constellation of Orion, has been undergoing unprecedented dimming. This image was taken in January using the European Southern Observatory's Very Large Telescope.

This new ALMA image shows the outcome of a stellar fight: a complex and stunning gas environment surrounding the binary star system HD101584.

NASA's Spitzer Space Telescope captured the Tarantula Nebula in two wavelengths of infrared light. The red represents hot gas, while the blue regions are interstellar dust.

A white dwarf, left, is pulling material off of a brown dwarf, right, about 3,000 light-years from Earth.

This image shows the orbits of the six G objects at the center of our galaxy, with the supermassive black hole indicated with a white cross. Stars, gas and dust are in the background.

After stars die, they expel their particles out into space, which form new stars in turn. In one case, stardust became embedded in a meteorite that fell to Earth. This illustration shows that stardust could flow from sources like the Egg Nebula to create the grains recovered from the meteorite, which landed in Australia.

The former North Star, Alpha Draconis or Thuban, is circled here in an image of the northern sky.

Galaxy UGC 2885, nicknamed the "Godzilla galaxy," may be the largest one in the local universe.

The host galaxy of a newly traced repeating fast radio burst acquired with the 8-meter Gemini-North telescope.

The Milky Way's central region was imaged using the European Southern Observatory's Very Large Telescope.

This is an artist's illustration of what MAMBO-9 would look like in visible light. The galaxy is very dusty and it has yet to build most of its stars. The two components show that the galaxy is in the process of merging.

Astronomers have found a white dwarf star surrounded by a gas disk created from an ice giant planet being torn apart by its gravity.

New measurements of the black hole at the center of the Holm 15A galaxy reveal it's 40 billion times more massive than our sun, making it the heaviest known black hole to be directly measured.

A close-up view of an interstellar comet passing through our solar system can be seen on the left. On the right, astronomers used an image of Earth for comparison.

The galaxy NGC 6240 hosts three supermassive black holes at its core.

Gamma-ray bursts are shown in this artist's illustration. They can be triggered by the collision or neutron stars or the explosion of a super massive star, collapsing into a black hole.

Two gaseous clouds resembling peacocks have been found in neighboring dwarf galaxy the Large Magellanic Cloud. In these images by the ALMA telescopes, red and green highlight molecular gas while blue shows ionized hydrogen gas.

An artist's impression of the Milky Way's big black hole flinging a star from the galaxy's center.

The Jack-o'-lantern Nebula is on the edge of the Milky Way. Radiation from the massive star at its center created spooky-looking gaps in the nebula that make it look like a carved pumpkin.

This new image from the NASA/ESA Hubble Space Telescope captures two galaxies of equal size in a collision that appears to resemble a ghostly face. This observation was made on 19 June 2019 in visible light by the telescope's Advanced Camera for Surveys.

A new SPHERE/VLT image of Hygiea, which could be the Solar System's smallest dwarf planet yet. As an object in the main asteroid belt, Hygiea satisfies right away three of the four requirements to be classified as a dwarf planet: it orbits around the Sun, it is not a moon and, unlike a planet, it has not cleared the neighbourhood around its orbit. The final requirement is that it have enough mass that its own gravity pulls it into a roughly spherical shape. This is what VLT observations have now revealed about Hygiea.

This is an artist's rendering of what a massive galaxy from the early universe might look like. The rendering shows that star formation in the galaxy is lighting up the surrounding gas. Image by James Josephides/Swinburne Astronomy Productions, Christina Williams/University of Arizona and Ivo Labbe/Swinburne.

This is an artist's illustration of gas and dust disk around the star HD 163296. Gaps in the disk are likely the location of baby planets that are forming.

This is a two-color composite image of comet 2I/Borisov captured by the Gemini North telescope on September 10.

This illustration shows a young, forming planet in a "baby-proof" star system.

Using a simulation, astronomers shed light on the faint gaseous filaments that comprise the cosmic web in a massive galaxy cluster.

The Hubble Space Telescope's Wide Field Camera observed Saturn in June as the planet made its closest approach to Earth this year, at approximately 1.36 billion kilometers away.

An artist's impression of the massive bursts of ionizing radiation exploding from the center of the Milky Way and impacting the Magellanic Stream.

The Atacama Large Millimeter/submillimeter Array captured this unprecedented image of two circumstellar disks, in which baby stars are growing, feeding off material from their surrounding birth disk.

This is an artist's illustration of what a Neptune-size moon would look like orbiting the gas giant exoplanet Kepler-1625b in a star system 8,000 light-years from Earth. It could be the first exomoon ever discovered.

This infrared image from NASA's Spitzer Space Telescope shows a cloud of gas and dust full of bubbles, which are inflated by wind and radiation from massive young stars. Each bubble is filled with hundreds to thousands of stars, which form from dense clouds of gas and dust.

This is an artist's impression of the path of the fast radio burst FRB 181112 traveling from a distant host galaxy to reach the Earth. It passed through the halo of a galaxy on the way.

After passing too close to a supermassive black hole, the star in this artist's conception is torn into a thin stream of gas, which is then pulled back around the black hole and slams into itself, creating a bright shock and ejecting more hot material.

Comparison of GJ 3512 to the Solar System and other nearby red-dwarf planetary systems. Planets around a solar-mass stars can grow until they start accreting gas and become giant planets such as Jupiter, in a few millions of years. But we thought that small stars such asProxima, TRAPPIST-1, Teegarderns star and GJ 3512, could not form Jupiter mass planets.

A collision of three galaxies has set three supermassive black holes on a crash course with each other in a system one billion light-years from Earth.

2I/Borisov is the first interstellar comet observed in our solar system and only the second observed interstellar visitor to our solar system.

KIC 8462852, also known as Boyajian's Star or Tabby's Star, is 1,000 light-years from us. It's 50% bigger than our sun and 1,000 degrees hotter. And it doesn't behave like any other star, dimming and brightening sporadically. Dust around the star, depicted here in an artist's illustration, may be the most likely cause of its strange behavior.

This is an artist's impression of a massive neutron star's pulse being delayed by the passage of a white dwarf star between the neutron star and Earth. Astronomers have detected the most massive neutron star to date due to this delay.

The European Southern Observatory's VISTA telescope captured a stunning image of the Large Magellanic Cloud, one of our nearest galactic neighbors. The near-infrared capability of the telescope showcases millions of individual stars.

Astronomers believe Comet C/2019 Q4 could be the second known interstellar visitor to our solar system. It was first spotted on August 30 and imaged by the Canada-France-Hawaii Telescope on Hawaii's Big Island on September 10, 2019.

A star known as S0-2, represented as the blue and green object in this artist's illustration, made its closest approach to the supermassive black hole at the center of the Milky Way in 2018. This provided a test for Einstein's theory of general relativity.

This is a radio image of the Milky Way's galactic center. The radio bubbles discovered by MeerKAT extend vertically above and below the plane of the galaxy.

A kilanova was captured by the Hubble Space Telescope in 2016, seen here next to the red arrow. Kilanovae are massive explosions that create heavy elements like gold and platinum.

This is an artist's depiction of a black hole about to swallow a neutron star. Detectors signaled this possible event on August 14.

This artist's illustration shows LHS 3844b, a rocky nearby exoplanet. It's 1.3 times the mass of Earth and orbits a cool M-dwarf star. The planet's surface is probably dark and covered in cooled volcanic material, and there is no detectable atmosphere.

An artist's concept of the explosion of a massive star within a dense stellar environment.

Galaxy NGC 5866 is 44 million light-years from Earth. It appears flat because we can only see its edge in this image captured by NASA's Spitzer Space Telescope.

The Hubble Space Telescope took a dazzling new portrait of Jupiter, showcasing its vivid colors and swirling cloud features in the atmosphere.

This is an artist's impression of the ancient massive and distant galaxies observed with ALMA.

Glowing gas clouds and newborn stars make up the Seagull Nebula in one of the Milky Way galaxy's spiral arms.

An artist's concept of what the first stars looked like soon after the Big Bang.

Spiral galaxy NGC 2985 lies roughly over 70 million light years from our solar system in the constellation of Ursa Major.

Early in the history of the universe, the Milky Way galaxy collided with a dwarf galaxy, left, which helped form our galaxy's ring and structure as it's known today.

An artist's illustration of a thin disc embedded in a supermassive black hole at the center of spiral galaxy NGC 3147, 130 million light-years away.

Hubble captured this view of a spiral galaxy named NGC 972 that appears to be blooming with new star formation. The orange glow is created as hydrogen gas reacts to the intense light streaming outwards from nearby newborn stars.

This is jellyfish galaxy JO201.

The Eta Carinae star system, located 7,500 light-years from Earth, experienced a great explosion in 1838 and the Hubble Space Telescope is still capturing the aftermath. This new ultraviolet image reveals the warm glowing gas clouds that resemble fireworks.

'Oumuamua, the first observed interstellar visitor to our solar system, is shown in an artist's illustration.

This is an artist's rendering of ancient supernovae that bombarded Earth with cosmic energy millions of years ago.

An artist's impression of CSIRO's Australian SKA Pathfinder radio telescope finding a fast radio burst and determining its precise location.

The Whirlpool galaxy has been captured in different light wavelengths. On the left is a visible light image. The next image combines visible and infrared light, while the two on the right show different wavelengths of infrared light.

Electrically charged C60 molecules, in which 60 carbon atoms are arranged in a hollow sphere that resembles a soccer ball, was found by the Hubble Space Telescope in the interstellar medium between star systems.

These are magnified galaxies behind large galaxy clusters. The pink halos reveal the gas surrounding the distant galaxies and its structure. The gravitational lensing effect of the clusters multiplies the images of the galaxies.

This artist's illustration shows a blue quasar at the center of a galaxy.

The NICER detector on the International Space Station recorded 22 months of nighttime X-ray data to create this map of the entire sky.

NASA's Spitzer Space Telescope captured this mosaic of the star-forming Cepheus C and Cepheus B regions.

Galaxy NGC 4485 collided with its larger galactic neighbor NGC 4490 millions of years ago, leading to the creation of new stars seen in the right side of the image.

Astronomers developed a mosaic of the distant universe, called the Hubble Legacy Field, that documents 16 years of observations from the Hubble Space Telescope. The image contains 200,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the Big Bang.

A ground-based telescope's view of the Large Magellanic Cloud, a neighboring galaxy of our Milky Way. The inset was taken by the Hubble Space Telescope and shows one of the star clusters in the galaxy.

One of the brightest planetary nebulae on the sky and first discovered in 1878, nebula NGC 7027 can be seen toward the constellation of the Swan.

The asteroid 6478 Gault is seen with the NASA/ESA Hubble Space Telescope, showing two narrow, comet-like tails of debris that tell us that the asteroid is slowly undergoing self-destruction. The bright streaks surrounding the asteroid are background stars. The Gault asteroid is located 214 million miles from the Sun, between the orbits of Mars and Jupiter.

The ghostly shell in this image is a supernova, and the glowing trail leading away from it is a pulsar.

Hidden in one of the darkest corners of the Orion constellation, this Cosmic Bat is spreading its hazy wings through interstellar space two thousand light-years away. It is illuminated by the young stars nestled in its coredespite being shrouded by opaque clouds of dust, their bright rays still illuminate the nebula.

In this illustration, several dust rings circle the sun. These rings form when planets' gravities tug dust grains into orbit around the sun. Recently, scientists have detected a dust ring at Mercury's orbit. Others hypothesize the source of Venus' dust ring is a group of never-before-detected co-orbital asteroids.

This is an artist's impression of globular star clusters surrounding the Milky Way.

An artist's impression of life on a planet in orbit around a binary star system, visible as two suns in the sky.

An artist's illustration of one of the most distant solar system objects yet observed, 2018 VG18 -- also known as "Farout." The pink hue suggests the presence of ice. We don't yet have an idea of what "FarFarOut" looks like.

This is an artist's concept of the tiny moon Hippocamp that was discovered by the Hubble Space Telescope. Only 20 miles across, it may actually be a broken-off fragment from a much larger neighboring moon, Proteus, seen as a crescent in the background.

In this illustration, an asteroid (bottom left) breaks apart under the powerful gravity of LSPM J0207+3331, the oldest, coldest white dwarf known to be surrounded by a ring of dusty debris. Scientists think the system's infrared signal is best explained by two distinct rings composed of dust supplied by crumbling asteroids.

An artist's impression of the warped and twisted Milky Way disk. This happens when the rotational forces of the massive center of the galaxy tug on the outer disk.

This 1.3-kilometer (0.8-mile)-radius Kuiper Belt Object discovered by researchers on the edge of the solar system is believed to be the step between balls of dust and ice and fully formed planets.

A selfie taken by NASA's Curiosity Mars rover on Vera Rubin Ridge before it moves to a new location.

The Hubble Space Telescope found a dwarf galaxy hiding behind a big star cluster that's in our cosmic neighborhood. It's so old and pristine that researchers have dubbed it a "living fossil" from the early universe.

How did massive black holes form in the early universe? The rotating gaseous disk of this dark matter halo breaks apart into three clumps that collapse under their own gravity to form supermassive stars. Those stars will quickly collapse and form massive black holes.

NASA's Spitzer Space Telescope captured this image of the Large Magellanic Cloud, a satellite galaxy to our own Milky Way galaxy. Astrophysicists now believe it could collide with our galaxy in two billion years.

A mysterious bright object in the sky, dubbed "The Cow," was captured in real time by telescopes around the world. Astronomers believe that it could be the birth of a black hole or neutron star, or a new class of object.

An illustration depicts the detection of a repeating fast radio burst from a mysterious source 3 billion light-years from Earth.

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Astronomers find the Wolfe Disk, an unlikely galaxy, in the distant universe - CNN

An image of a mesmerizing cosmic spiral, twisting and swirling around a galactic maw, may be the first direct evidence of the birth of a planet ever captured by humanity.

The European Southern Observatory released a picture Wednesday of what astronomers believe shows the process of cosmic matter at a gravitational tipping point, collapsing into a new world around a nearby star.

Astronomers said the dramatic scene offers a rare glimpse into the formation of a baby planet, which could help scientists better understand how planets come to exist around stars.

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"Thousands of exoplanets have been identified so far, but little is known about how they form," the lead author of a study detailing the discovery, Anthony Boccaletti, an astronomer at the Observatoire de Paris in France, said in a statement.

Planets are thought to form out of the massive discs of gas and dust that surround young stars. As tiny specks of dust circle a star and collide with one another, some material starts to fuse, much like how rolling a snowball through more snow will eventually yield a bigger snowball. After billions of years, the clumps of material become large enough that the force of gravity shapes them into planets.

The new image peers into the disc of material around a young star known as AB Aurigae, which is 520 light-years from Earth in the constellation of Auriga. Amid the hypnotic spiral arms is a "twist," visible in the photo as a bright yellow region in the center, that is thought to be a sign of a planet being born, said Emmanuel Di Folco, a researcher at the Astrophysics Laboratory of Bordeaux in France, who participated in the study.

When a planet forms, the clumps of material create wavelike perturbations in the gas- and dust-filled disc around a star, "somewhat like the wake of a boat on a lake," Di Folco said.

The bright region at the center of the new image is thought to be evidence of such a disturbance, which had been predicted in models of planetary birth.

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"The twist is expected from some theoretical models of planet formation," said Anne Dutrey, an astronomer at the Astrophysics Laboratory of Bordeaux and co-author of the study, published Wednesday in the journal Astronomy & Astrophysics. "It corresponds to the connection of two spirals one winding inwards of the planet's orbit, the other expanding outwards which join at the planet location."

The new observations of the baby planet were made in 2019 and early 2020 by the European Southern Observatory's Very Large Telescope in the Atacama Desert in northern Chile. The research team, made up of astronomers from France, Taiwan, the U.S. and Belgium, said the images are the deepest observations of the AB Aurigae system made to date.

Denise Chow is a reporter for NBC News Science focused on the environment and space.

Here is the original post:

In an orange swirl, astronomers say humanity has its first look at the birth of a planet - NBCNews.com

In the far reaches of the Solar System, past the orbit of Neptune, things start getting trickier and trickier to see. Directly imaging small objects out in the darkness of the Kuiper Belt - where Pluto resides - is really difficult, which makes a recent discovery all the more exciting.

If you know where something is, you can observe it by waiting for it to pass in front of distant stars. This is called occultation, and astronomers use it to study all sorts of trans-Neptunian objects.

But when astronomers used occultation in 2018 to study one such object they've been watching for nearly two decades, they found something really unexpected - a chonk of a moon, relative to the body it is orbiting. A study describing their findings has now been accepted into Astronomy & Astrophysics,and was first covered by Jonathan O'Callaghan over atNew Scientist.

The object caught sporting this moon is probable dwarf planet (84522) 2002 TC302.It was first discovered in 2002, after which it was also identified in earlier observations.

Between 2000 and 2018, astronomers collected at least 126 observations of the object across a variety of wavelengths (including the Hubble Space Telescope); using this information, they calculated the potential dwarf planet's orbit, size, and colour.

They found that it's around 584 kilometres (363 miles) in diameter,and with an orbital period of 417 years - in a 2:5 orbital resonance with Neptune.

That's pretty awesome. It means 2002 TC302 almost meets the requirements for a dwarf planet - it's in orbit around the Sun (but not another planet); it hasn't cleared its orbital neighbourhood; and it must have enough mass to achieve hydrostatic equilibrium, or a round shape.

But we're not quite sure. When predictions of its orbit pointed to an occultation event on 28 January 2018, observatories around Europe pointed their eyes at 2002 TC302's neighbourhood to try and figure out its physical properties, such as size and shape.

Telescopes in Italy, France, Slovenia and Switzerland made 12 positive detections of the occultation event, as well as four negative detections. This produced the best observation of a trans-Neptunian object we've obtained to date, the researchers said.

Adding these together allowed the researchers to obtain a new, more accurate measurement of the object's diameter: 500 kilometres (311 miles).

So, how to account for the missing 84 kilometres calculated from the other observations? Well, there's a really interesting answer to that. If 2002 TC302 had a moon around 200 kilometres (124 miles) in diameter, and just 2,000 kilometres (1,243 miles) from the probable dwarf planet, it could produce the signal that other astronomers interpreted as a slightly larger 2002 TC302.

This is crazy close. The Moon, for context, is 384,400 kilometres (238,900 miles) from Earth (on average). At such a close proximity, 2002 TC302's satellite would be extremely hard to image - not even the Hubble Space Telescope images taken in 2005 would be able to resolve it individually.

If the potential dwarf planet really has a satellite, that can help us learn things about the early Solar System. Stuff in the Kuiper Belt has changed very little since the Solar System formed, and as such, these objects are considered time capsules.

Two objects extremely close together could help us to better understand close interactions when the Solar System was forming. Since the planets are thought to have formed via accretion - more and more stuff sticking together - this could be an important clue as to how smaller bodies grow.

An object of similar interest is Arrokoth, the weird snowman-shaped rock visited by the New Horizons probe in 2015. The data provided by that flyby showed us that planetary accretion may be a more gentle process than we thought.

2002 TC302 is a lot bigger than Arrokoth, but it could be at a later stage of the process - which would be really useful in piecing together the stages in which it happens. At any rate, it's clear that we should probably look at it a bit more and try to figure out what its deal is. Exciting!

The research has been accepted into Astronomy & Astrophysics, and is available on arXiv.

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Astronomers May Have Spotted a Tiny Moon in The Outer Solar System - ScienceAlert

Look to the north-west on the evening of Friday 22 May, soon after sunset, to enjoy a spectacular coming together of brilliant Venus and shy and elusive Mercury. The planetary pair are separated in the sky by just 1.3 degrees (77 arcminutes), which is just over two full-Moon diameters. (Another easy-to-demonstrate method of gauging how far this is, is that a finger held out at arms length covers approximately one degree.) Given clear skies, with a few caveats, this exciting event can be enjoyed even from light-polluted towns and cities.

The one fly in the ointment is that the conjunction occurs at an altitude of less than 10 degrees, so youll need to have a horizon from the west-north-west around to the north-west (azimuth 290 to 315 degrees; check your smartphones compass) thats free from obscuring buildings and trees. If you can secure a good view, then this event should be readily visible with the naked eye, but have a pair of binoculars or a small telescope, operating at a low magnification, to hand in case the early evening is hazy. Sunset in London occurs shortly before 9pm BST (20:00 UT), at 9.14pm in Manchester and just after 9.30pm in Edinburgh.Your smartphones weather app can give your local sunset time.

If you have to use binoculars to view the conjunction, then make absolutely sure that the Sun has set below the horizon at your location before sweeping across the sky. If the Sun enters the field of view of any optical aid that you are using, its heat and light can cause catastrophic damage to your eyesight.

Venus will be the first astronomical object to appear in the deepening twilight. Even casual stargazers cant have failed to notice the blazing evening star that has recently seemed an almost permanent fixture in the post-sunset western sky, especially given the fine weather and clear skies most of the UK has been enjoying. The more committed observers will have noticed that the gloss has been coming off Venus brilliance as May has progressed, with the planet sinking lower in the sky and its brightness dimming somewhat. Having said this, Venus is still a blazing beacon, shining at magnitude 4.2.

It shouldnt be too long into the evening before Mercury appears alongside Venus, placed to Venus left at roughly the same altitude. Mercury has been on the scene for about a week now, itself shining significantly brighter than any star visible from UK shores at this time of year, as it has been climbing steadily away from the north-western horizon. This evening it shines at magnitude 0.5.

The end of civil twilight (when the Sun lies six degrees below the horizon) usually signals the appearance of the brighter stars. In London, this occurs at about 9.40pm BST (20.40 UT) and at 10pm and 10.25pm, from Manchester and Edinburgh, respectively. The planetary pair lie at an altitude just short of eight degrees as seen from London, and just over six and seven degrees as seen from Edinburgh and Manchester, respectively.

During any moments of steady seeing (often fleeting at such a low elevation), it might be possible to glean Venus extremely thin crescent disc through a pair of binoculars. Its elongation from the Sun is only 20 degrees and so it exhibits just a 5.3 per cent-illuminated phase some 53 arcminutes in size. A small telescope would be a better bet to see this, as well as resolving Mercurys 67 per cent-illuminated gibbous phase.

Experienced observers can observe this conjunction in broad daylight, as Venus and Mercury are actually at their closest of 0.9 degree (53 arcminutes) at around 9am BST (08:00 UT). At this time, the pair lie about 27 degrees above the eastern horizon from London, and culminate due south at an advantageous 65-degree altitude at around 2.15pm BST, when their separation has widened to nearly 56 arcminutes. Viewing astronomical objects that are close to the Sun in broad daylight is fraught with danger, given the risk of damaging your eyes by looking at the Sun, so this is not recommended for casual or inexperienced observers.

If you are clouded out or cant be free to observe this conjunction, then two evenings later, on Sunday 24 May, look out for when the young crescent Moon muscles in on the scene. It appears above five degrees to the left of Mercury, which is now separated from Venus by just over five degrees.

Venus now rapidly departs the evening sky on its way to inferior conjunction (between us and the Sun) on 3 June. Its been a memorable evening apparition and, in whats a great year for Venus fanciers, the planet returns as a blazing morning star in July, for what promises to be a splendid morning apparition that lasts almost until the end of 2020.

Mercury makes further strides in evening visibility to put on a fine evening apparition, centred on a greatest eastern elongation from the Sun on 4 June.

Its not all that common to see the two innermost, or so-called inferior planets, come this close together, so make the most of it should the sky be clear for you.

Read more here:

Here's your chance to spot Mercury, as it cosies up to Venus this weekend - Astronomy Now Online

In the mid-2020s, NASAs next-generation Wide Field Infrared Survey Telescope (WFIRST) will take to space. With unprecedented resolution and advanced instruments, it will build on the foundation established by the venerable Hubble Space Telescope which celebrated its 30th anniversary this year! In anticipation of all it will accomplish, NASA decided that the WFIRST needs a proper name, one that honors its connection to Hubble.

This week, NASA announced that henceforth, the WFIRST mission will be known as the Nancy Grace Roman Space Telescope (or Roman Space Telescope for short) in honor of Dr. Nancy Grace Roman (who passed away in 2018). In addition to being NASAs first Chief Astronomer, she was also a tireless educator and advocate for women in STEMs whose work paved the way for space telescopes leading to her nickname the mother of Hubble.

Its therefore only fitting that we take a look at the inspiring life of this pioneer and the work that earned her a place among the stars!

Born in Nashville, Tennessee in 1925, Roman demonstrated a fascination with astronomy early in life. After forming an astronomy club with classmates in middle-school, Roman decided by the time she reached high school that she wanted to pursue astronomy as a career (though she was discouraged by those around her).

After graduating, she attended Swarthmore College in Pennsylvania and worked at the Sproul Observatory. She then pursued her graduate studies at the University of Chicago while conducting research at the Yerkes Observatory in Wisconsin and the McDonald Observatory in Texas, eventually becoming an assistant professor.

However, due to the dearth of tenured positions available to women at the time, she eventually took a position at the Naval Research Laboratory (ARL) in 1954 on the recommendation of fellow astronomer Gerard Kuiper. Over the next three years, she contributed to the emerging field of radio astronomy and become head of the ARLs microwave spectroscopy section.

During her time with the ARL, Roman came to the attention of the international astronomical community and traveled overseas to lecture on her research. Her work was also noticed by the newly-formed National Aeronautical and Space Administration (NASA) and in 1959, she joined NASA to spearhead its program for observational astronomy.

Her acceptance into NASA as their Head of Observational Astronomy effectively meant that she would be giving up her research, but she felt that the sacrifice was worth it. As she was quoted as saying in a memoir published in 2018, the chance to start with a clean slate to map out a program that I thought would influence astronomy for fifty years was more than I could resist.

By the early 1960s, she became the first Chief of Astronomy in NASAs Office of Space Science and traveled extensively across the US to deliver lectures to astronomy departments and promote NASA programs. In her own words, the visits were intended to tell them what we were planning at NASA and what the NASA opportunities were, but it was equally to try to get from them a feeling of what they thought NASA ought to be doing.

By the mid-1960s, she established a committee of astronomers and engineers to envision a telescope that could conduct observations from space and accomplish important scientific goals. In time, her advocacy convinced NASA and Congress to make the creation of a space telescope a priority. Her efforts were realized in 1990 with the launch of Hubble, which was to be the most scientifically revolutionary space telescope of all time.

Since Hubble took to space, its science operations have been coordinated and overseen by the Space Telescope Science Institute (STScI) in Baltimore, Maryland. This consisted of scheduling and carrying out observations, processing and archiving mission datasets, and performing outreach programs with the astronomical community and general public.

Next year, when the James Webb Space Telescope is launched into orbit, its science and mission operations centers will also be housed in the STScI. In 2019, NASA announced that STScI would also serve as the science operations center for the Roman Space Telescope. AS STScI Director Kenneth Sembach said:

Dr. Nancy Grace Roman was an accomplished scientist and leader, as well as a staunch advocate of Hubble and NASAs other Great Observatories. She also strongly backed the creation of STScI. We thought of her as a colleague and friend, and were delighted to welcome her to the Institute for our annual spring science symposium in 2017...

We are honored to be part of her continuing legacy. Our entire team stands ready to support the astronomical community and ensure that the Roman Space Telescope will achieve its full scientific potential.

Like its predecessors, all the data collected by the Roman Space Telescope will be kept in the Barbara A. Mikulski Archive for Space Telescopes (MAST) at the STScI, where it will readily available for investigators, researchers, and astronomers around the world. It is estimated that over its planned 5-year mission, the observatory will collect an estimated 20 petabytes (PB) of data.

In comparison, The British Library, the largest national library in the world and one of the largest databases in existence, contains roughly 500 terabytes of preserved data. Doing the math, we can safely say that the RST will gather the equivalent of 40 British Libraries. The availability of all this data is sure to keep scientists engaged and fuel discoveries long after the mission is over.

The Roman Space Telescope will bring big data to space astrophysics, said STScI Deputy Director Nancy Levenson. The large and freely accessible data sets will inspire new ways of exploring the cosmos, advancing our understanding and presenting new mysteries.

As noted in previous articles, the RST will have the power of 100 Hubbles. What this means is that while the RST will have the same sensitivity and resolution as Hubble, it will be able to cover a viewing area 100 times larger. This is made possible by the telescopes 18 detectors (4096 x 4096 pixels each), which allow the RST to cover an area roughly 1.33 times that of a Full Moon Hubble images cover an area less than 1% that of a Full Moon.

Its advanced suite of scientific instruments will also allow it to conduct a wide array of astronomical observations. This includes the Wide-Field Instrument (WFI), a 288-megapixel camera that is capable of multi-band near-infrared imaging. This will allow the RST to observe diverse populations of astronomical objects that are otherwise unobservable in visible light.

The RST will also work in concert with the James Webb Space Telescope (JWST) for the sake of conducting in-depth radio observations. This will consist of the RST taking advantage of its wide field of view to reveal diverse populations of astronomical objects in infrared wavelengths while the JWST conducts follow-up observations using its superior infrared imaging capabilities.

Then theres the high contrast coronagraph the telescope will use to suppress light coming from distant stars, which will allow astronomers to conduct direct imaging studies of smaller, rocky exoplanets that orbit closer to their stars. This will enable more detailed studies of potentially habitable planets, better characterizations of their atmospheres, and the identification of potential biosignatures.

Another thing that the RST will have going for it is its proposed orbit, which will give it a view of space largely unobstructed by Earth. Whereas Hubbles Low Earth Orbit (LEO) of about 560 km (350 mi) often means that it is obnly able to collect data for half of its orbital period, the RST will be in a wide orbit of about 1.6 million km (1 million mi) and able to make observations in an almost continuous fashion.

Like the other NASA Great Observatories (the Compton Gamma Ray Observatory, the Chandra X-ray Observatory, Hubble, and the Spitzer Space Telescope), the RST will help spur advances in many fields of astrophysics. This will include completing the census of exoplanets by discovering thousands of new worlds and characterizing them, as well as the study of comets, asteroids, dwarf planets, and ocean worlds in our Solar System.

The RST will also observe billions of star systems, some of which are still in the process of formation, and millions of galaxies and their surrounding structures. In the process, it will shed light on enduring cosmic mysteries like Dark Matter, Dark Energy, and the role they have played in cosmic evolution. Lastly, the RST will use its superior imaging capabilities to study the earliest stars and galaxies in our Universe.

In short, the Roman Space Telescope will allow researchers and astronomers to do precisely what Dr. Roman herself once said: If you enjoy puzzles, science or engineering may be the field for you, because scientific research and engineering is a continuous series of solving puzzles.

It is no exaggeration to say that the Hubble Space Telescope owes its very existence to Dr. Nancy Grace Roman. It is therefore very fitting that the space telescope that will build on the foundation established by Hubble (and also greatly expand upon it) will be named after its mother. She would no doubt be very happy that the WFIRST bears her name in recognition of her accomplishments.

But I think its safe to say that she would be more pleased to know that the tradition of space-based observatories has carried on in her absence and it is becoming even more bold and sophisticated. She would also be very pleased to know that the discoveries these next-generation telescopes promise will be that much more profound.

Be sure to check out this video on the life and contributions of Dr. Roman, courtesy of NASA Goddard:

Further Reading: NASA Hubblesite, Nancy Grace Roman Space Telescope

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WFIRST Will be Named After Nancy Grace Roman, NASA's First Chief Astronomer - Universe Today

A new study uses Bayesian statistics to weigh the likelihood of life and intelligence beyond our solar system. Credit: Amanda Carden

New study uses Bayesian statistics to shed light on how extraterrestrial life might evolve beyond our planet.

Humans have been wondering whether we alone in the universe since antiquity.

We know from the geological record that life started relatively quickly, as soon our planets environment was stable enough to support it. We also know that the first multicellular organism, which eventually produced todays technological civilization, took far longer to evolve, approximately 4 billion years.

But despite knowing when life first appeared on Earth, scientists still do not understand how life occurred, which has important implications for the likelihood of finding life elsewhere in the universe.

In a new paper published in the Proceeding of the National Academy of Sciences today, David Kipping, an assistant professor in Columbias Department of Astronomy, shows how an analysis using a statistical technique called Bayesian inference could shed light on how complex extraterrestrial life might evolve in alien worlds.

The rapid emergence of life and the late evolution of humanity, in the context of the timeline of evolution, are certainly suggestive, Kipping said. But in this study its possible to actually quantify what the facts tell us.

To conduct his analysis, Kipping used the chronology of the earliest evidence for life and the evolution of humanity. He asked how often we would expect life and intelligence to re-emerge if Earths history were to repeat, re-running the clock over and over again.

He framed the problem in terms of four possible answers: Life is common and often develops intelligence, life is rare but often develops intelligence, life is common and rarely develops intelligence and, finally, life is rare and rarely develops intelligence.

This method of Bayesian statistical inferenceused to update the probability for a hypothesis as evidence or information becomes availablestates prior beliefs about the system being modeled, which are then combined with data to cast probabilities of outcomes.

The technique is akin to betting odds, Kipping said. It encourages the repeated testing of new evidence against your position, in essence a positive feedback loop of refining your estimates of likelihood of an event.

From these four hypotheses, Kipping used Bayesian mathematical formulas to weigh the models against one another. In Bayesian inference, prior probability distributions always need to be selected, Kipping said. But a key result here is that when one compares the rare-life versus common-life scenarios, the common-life scenario is always at least nine times more likely than the rare one.

The analysis is based on evidence that life emerged within 300 million years of the formation of the Earths oceans as found in carbon-13-depleted zircon deposits, a very fast start in the context of Earths lifetime. Kipping emphasizes that the ratio is at least 9:1 or higher, depending on the true value of how often intelligence develops.

Kippings conclusion is that if planets with similar conditions and evolutionary time lines to Earth are common, then the analysis suggests that life should have little problem spontaneously emerging on other planets. And what are the odds that these extraterrestrial lives could be complex, differentiated and intelligent? Here, Kippings inquiry is less assured, finding just 3:2 odds in favor of intelligent life.

This result stems from humanitys relatively late appearance in Earths habitable window, suggesting that its development was neither an easy nor ensured process. If we played Earths history again, the emergence of intelligence is actually somewhat unlikely, he said.

Kipping points out that the odds in the study arent overwhelming, being quite close to 50:50, and the findings should be treated as no more than a gentle nudge toward a hypothesis.

The analysis cant provide certainties or guarantees, only statistical probabilities based on what happened here on Earth, Kipping said. Yet encouragingly, the case for a universe teeming with life emerges as the favored bet. The search for intelligent life in worlds beyond Earth should be by no means discouraged.

Reference: An objective Bayesian analysis of lifes early start and our late arrival by David Kipping, 18 May 2020, Proceedings of the National Academy of Sciences.DOI: 10.1073/pnas.1921655117

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Columbia Astronomer Estimates the Odds of Extraterrestrial Life and Intelligence Emerging in Alien Worlds - SciTechDaily

This story appeared in the June 2020 issue as "A Universe of Galaxies."Subscribeto Discover magazine for more stories like this.

On the evening of Oct. 4, 1923, near Los Angeles, a young astronomer got into his car and began a motorized trek up to Mount Wilson. There, he arrived at the observatory that housed the 100-inch Hooker Telescope, at the time the largest telescope in the world.

Edwin Hubble was a fourth-year astronomer at Mount Wilson; he enjoyed using the Hooker Telescope because he was interested in, among other things, studying spiral nebulae. These mysterious gas clouds were scattered across the sky, and no one understood their nature. In the early days of the 1920s, Hubble had assigned himself the task of figuring them out.

He pointed the great telescope toward his favorite object: the nebula in Andromeda, M31. This spiral-shaped cloud is faintly visible to the naked eye under a clear, moonless sky. He then captured its image on a photographic plate. Hubble was excited by the result. On it, he found a suspected nova, an exploding star. The next night, he photographed M31 again, hoping to catch the nova and record it under better atmospheric stability. The second plate did indeed record the nova, but little did he know, he also had captured a plate that would become legendary in the history of science.

Astronomer Edwin Hubble made an exposure of the Andromeda Nebula with the Hooker Telescope at Mount Wilson Observatory near Los Angeles on Oct. 5, 1923. He was initially excited, believing he had recorded a nova, an exploding star. He marked the star, which lies between two tick marks he drew at the top right on the plate, with the letter N. The star turned out to be a Cepheid variable, and Hubble used it to prove that the distance to the Andromeda Galaxy was far greater than astronomers thought. (Credit: Courtesy of the Carnegie Observatories/Cindy Hunt)

His observing time over, he returned to his office to analyze the catch. Suddenly, Hubble made an astonishing realization: The nova was not a nova at all, but a particular type of star that changed its brightness, a Cepheid variable. Checking earlier plates, he was able to confirm that, and he realized that the stars faintness had incredible implications.

The star, and the nebula that encompassed it, must lie at a distance of a million light-years three times larger than anyone at the time believed the size of the whole universe to be. Today, thanks to improved measurements, astronomers know the object is 2.5 million light-years away.

Aided in part by earlier work done by Vesto M. Slipher and by his own colleague, Milton Humason, Hubble had at once discovered that the universe was far larger than anyone had believed, and that spiral nebulae like Andromeda were actually distant galaxies. They were whole systems of stars and gas, separated from our own Milky Way by a long hike.

At Arizonas Lowell Observatory, as early as 1912, Slipher had recorded the apparent velocities of spiral nebulae and, with the work now done by Hubble, it was clear the universe was expanding the galaxies were flying apart from one another over time. The universe was not only far larger than anyone had previously believed, but it was growing as time went on.

NGC 4565 in Coma Berenices is the brightest and most prominent galaxy in our sky that is oriented perfectly edge-on to our line of sight. We see its disk as a thin, silvery needle. Some 57 million light-years off, it lies in the Virgo Cluster and has a prominent central bulge, suggesting it may be a barred spiral. (Credit: Adam Block)

By 1929, astronomers had put a cosmic picture of the past together. If you traced the histories of many of the galaxies backward in time, it meant that the cosmos began with a small, infinitely dense point at its origin. This research was an extension of work originally done by Belgian astronomer Georges Lematre. Astronomers understood this cosmic point of origin, later called the Big Bang, as the start of the universe, and, they calculated, it must have occurred billions of years ago. The Big Bang had commenced the expansion that was driving all the galaxies away from each other as time rolls on. The whole universe seemed to be flying apart.

In the 1930s, Hubble began to study and classify galaxies into their various so-called morphological types, the array of structures astronomers saw in photographs. He eventually assembled the types of galaxies he observed into a tuning fork-shaped diagram. It contained spiral galaxies, barred spiral galaxies spirals containing a linear bar of material passing through their centers lenticular (lens-shaped) galaxies, and elliptical galaxies. He also identified irregular galaxies, clouds of stars and gas that lacked an organized shape. Later on, astronomers would identify peculiar galaxies, systems that appeared to be wracked with explosive or disruptive events. They also identified a class of galaxies called dwarf spheroidals, which seemed to be numerous in the local universe.

By the 1950s, French astronomer Grard de Vaucouleurs of the University of Texas had expanded Hubbles classification scheme into a more complex system that took into account many observed properties of galaxies. De Vaucouleurs produced a pseudo-three-dimensional plot showing the galaxies relationships, nicknamed the Cosmic Lemon due to its shape. De Vaucouleurs included details on bars in galaxies, descriptions of rings of matter visible in them, and an evaluation of how loosely or tightly the spiral arms of a galaxy were wound. He also included evaluative details about the nature of irregular and peculiar galaxies.

The last generation of extragalactic astronomy has moved into far more sophisticated analyses than cataloging. By using the Hubble Space Telescope, astronomers have estimated that some 100 billion galaxies must exist in the cosmos. And the number may be much greater than that. Probably some 2 trillion galaxies existed in the early universe, but it seems clear that galaxies near each other are drawn together by gravity and combine over cosmic time. Despite the universal expansion, then, normal galaxies like the Milky Way are probably made of dozens or more protogalaxies that merged into larger systems. You can see these primitive blobs of matter, bluish protogalaxies, in the early universe within the Hubble Ultra Deep Field pictures.

Perseus A, also called NGC 1275, is an eruptive galaxy at the core of the Perseus Cluster, which is made up of some 1,000 galaxies about 240 million light-years away. The dominant member of the Perseus Cluster, Perseus A is a Seyfert galaxy with an active nucleus, powered by a 340-million-solar-mass black hole in its core. (Credit: Hubble Legacy Archive, ESA, and NASA)

As astronomers have studied greater numbers of galaxies over the past few decades, theyve discovered many things, but one that is impossible to ignore is that the universe is incredibly large. If you look at a galaxy in your telescopes eyepiece tonight, the photons striking your eye have been traveling at the fastest speed there is 186,000 miles per second (300,000 kilometers per second). Nonetheless, they have taken 2.5 million years at that velocity to reach us from the Andromeda Galaxy. And that object is nearly on our cosmic doorstep. Of course, the knowledge of our own galaxy, in a primitive sense, goes back to antiquity. The name Milky Way comes from the Latin via lactea, which derives from the original idea, the Greek term, galaxas kklos, milky circle. The band of Milky Way visible in our sky, most prominently in the summer and winter evenings, is the unresolved light from billions of stars lying along the plane of our galaxy.

But only in the past few decades have we come to understand that the Milky Way is one of the 100 billion galaxies in the universe, and that its disk stretches some 100,000 light-years across. It contains some 400 billion stars, although we dont know exactly how many because dwarf stars are faint and difficult to see over long distances. For decades, astronomers believed the Milky Way was a simple spiral galaxy. But studies in this century have shown the Milky Way is a barred spiral, and that our sun and solar system lie some 26,000 light-years from the center, in one of the galaxys arms.

The Milky Way consists of a bright disk, a slowly spinning platter of stars and gas that contains most of the stars we see. Our sun orbits the center of the galaxy once every 220 million years, meaning that weve rotated around the galactic center about 20 times since the formation of the solar system. Far away, in the center of the galaxy, lies a supermassive black hole containing around 4.3 million times more mass than the sun. In recent times, astronomers have discovered that supermassive black holes in the centers of galaxies are the norm. Nearly all galaxies, except for dwarfs, have them.

The galaxys disk is encapsulated by a halo of a small number of stars, along with huge spheres of ancient stars called globular star clusters, and a big envelope of dark matter. Astronomers dont yet know what dark matter consists of, but they know it is there because of the gravitational influence it has on the visible matter they can observe.

The weirdly distorted elliptical galaxy NGC 474 in Pisces lies at a distance of 100 million light-years. The neighboring spiral galaxy NGC 470 lies just above it. Multiple shells and tidal tails surround NGC 474, caused by interactions with its neighbors and by density waves that propagate through the medium. This mammoth object stretches 250,000 light-years across two and a half times the diameter of the Milky Way. (Credit: P-A. DUC (CEA, CFHT), ATLAS 3D Collaboration)

The Milky Way is hardly alone in the cosmos. It belongs to a group of at least 54 objects called the Local Group of galaxies, a name Hubble gave to this local cloud of objects as he mapped the nearby cosmos. The primary members of the Local Group are the Milky Way, the Andromeda Galaxy, and the Pinwheel Galaxy (M33). But each of these big three spirals has a cloud of attendant galaxies, too. The Milky Ways satellites include the Large and Small Magellanic Clouds, visible to the naked eye in the Southern Hemisphere, and many dwarf galaxies. The diameter of the Local Group is about 10 million light-years, some 100 times the diameter of the Milky Way.

And moving outward into the deeper universe, we encounter more examples of those 100 billion galaxies. These majestic islands of stars and gas exist in groups, like our Local Group, but also in larger assemblages called clusters and very large ones called superclusters. Despite the overall expansion of the universe, meaning that most galaxies are moving away from each other as the cosmos grows, gravity keeps smaller numbers of galaxies bound to each other on their journeys. Our Local Group, for example, is a member of the so-called Virgo Cluster of galaxies, named so because its richly populated center lies in the constellation Virgo in our sky.

The Virgo Cluster contains at least 1,500 galaxies and is centered some 54 million light-years from Earth. You can see some of the brightest galaxies near the core of the Virgo Cluster in amateur telescopes, in an array called Markarians Chain. This line of galaxies contains supermassive elliptical galaxies such as M84 and M86, and a variety of spiral galaxies, too. For backyard astronomers, this playground of galaxy types is one of the really entrancing areas of the sky, and it is best visible on springtime evenings under clear, moonless conditions.

Most of the Virgo Cluster galaxies contain supermassive black holes in their centers. M87 is quite an example. Whereas the Milky Ways central black hole weighs in at 4.3 million solar masses, the colossal black hole inside M87 contains an estimated mass of 5 billion to 7 billion suns, some 1,000 times more massive than ours. M87 is one of the largest galaxies in our part of the universe it is a so-called cD galaxy, short for centrally dominant and it has eaten many of the smaller galaxies that once surrounded it. Thats what massive galaxies do they consume their neighborhood partners.

One of the greatest edge-on galaxies in the sky, and the one most people say looks like a flying saucer, is the Sombrero Galaxy (M104) in Virgo. It consists of a great rotating disk with a prominent dust lane edging it, consumed by a glowing halo of gas and stars. It lies 43 million light-years away and is about half the size of the Milky Way, sporting a diameter of 49,000 light-years. (Credit: NASA and the Hubble Heritage Team (AURA/STScI))

A cluster containing 1,500 galaxies is one thing, but much larger assemblages of galaxies also exist. The Virgo Cluster itself is a member of the so-called Virgo Supercluster, which holds thousands of galaxies on a scale an order of magnitude larger yet. The Virgo Supercluster holds our Milky Way, the Local Group, the Virgo Cluster, and altogether some 100 galaxy groups and clusters. This amazingly large framework stretches some 110 million light-years across, and is one of about 10 million superclusters that make up the entire cosmos.

Despite the huge number of galaxies existing in the Virgo Supercluster, astronomers now know that most of the space in this volume is essentially empty. The diameters of these great voids range from dozens to hundreds of millions of light-years. Filamentary chains of galaxies wind their way around the dark, empty spaces. On large scales, galaxies in clusters and superclusters are like soap bubbles, with galaxies coating the surfaces and voids lying in between.

The Whirlpool Galaxy in Canes Venatici, another galaxy near the Big Dipper, is also known as M51 and is a top telescope target. An interacting pair of galaxies, the Whirlpool is being passed by a little interloper, NGC 5195, which is drawing material off one of the larger galaxys spiral arms. The pair lies 23 million light-years away, and M51s disk stretches across 60,000 light-years. (Credit: Tony Hallas)

By the end of the 1980s, astronomers had identified the Great Wall, a sheet of galaxies measuring 500 million light-years across. More recently, the Sloan Digital Sky Survey uncovered the Sloan Great Wall, an assemblage of galaxies at least twice the size of the Great Wall, which covers a long dimension of some 1.4 billion light-years.

As astronomers discovered more and more distant galaxies, they found that some large mass seemed to be tugging on the local universe, pulling us in the direction of the southern constellations Triangulum Australe and Norma. Called the Great Attractor, this anomaly, some 200 million light-years away, puzzled astronomers. They eventually discovered that an even larger mass in that direction was pulling us. This mammoth structure, called the Shapley Supercluster, is 650 million light-years away and contains the greatest concentration of galaxies in our local part of the cosmos.

Elliptical galaxies like M49 in Virgo are huge spheres of stars that float in an ellipsoidal cloud. Althoughtheir diameters are often similar to large spiral galaxies, they can hold vastly more mass because they are shaped like a football rather than a disk. This galaxy lies some 56 million light-years away and is one of the more massive galaxies in the Virgo Cluster. (Credit: NASA/ESA/STScI)

Additional surprising discoveries have occurred, too. In 2014, astronomers identified a new supercluster based on the relative motions of galaxies analyzed in a more sophisticated way than ever before. University of Hawaii astronomers concluded that the Laniakea Supercluster exists, and named it after the Hawaiian word for immense heaven.

Laniakea, which is also sometimes called the Local Supercluster, contains some 100,000 galaxies, including the Local Group and the Milky Way. This massive cluster and all its members are traveling together through space, but not all of the galaxies within it are gravitationally bound. Some will splinter apart from the rest of the cluster as time rolls on.

The Laniakea Supercluster has four major components the Virgo Supercluster, the Hydra-Centaurus Supercluster, the Pavo-Indus Supercluster, and the Southern Supercluster.

Altogether, Laniakea contains around 500 galaxy clusters and groups. And surrounding Laniakea in the local universe are other galaxy superclusters the Shapley Supercluster, the Hercules Supercluster, the Coma Supercluster, and the Perseus-Pisces Supercluster. Each of these structures holds hundreds of galaxy clusters and are linked by the fabriclike web of cosmic structure.

Beginning in the 1980s, astronomers found evidence of structures even larger than superclusters. At first, objects now called Large Quasar Groups (LQG) baffled astronomers.

In 1982, Scottish astronomer Adrian Webster found what would become known as the Webster Large Quasar Group, a collection of five quasars, or actively feeding black holes, stretching over 330 million light-years. Now, nearly two dozen LQGs are known. A structure known as the Huge LQG contains 73 quasars over a diameter of some 4 billion light-years. This massive structure, dismissed by some astronomers, may hold the title as the largest collection of related matter in the cosmos.

Truly, the universe is so big that its hard to comprehend. On one hand, the enormity of the universe makes us feel small. Our brief lives happen so quickly, and we wink out, mostly unaware of the incredibly large cosmos around us. But the fact that we are sentient, that we can ponder the stars and galaxies far away from us, makes life in the universe a truly amazing thing. And were just starting to get to know the immense world of galaxies.

David J. Eicher is the editor of Astronomy. His 2020 book, Galaxies: Inside the Universes Star Cities, is available from My Science Shop.

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How Many Galaxies Are There? Astronomers Are Revealing the Enormity of the Universe - Discover Magazine