Category Archives: Hubble Telescope

The Hubble Space Telescope is one of the most powerful technologies available for measuring interstellar distances.

Hubble is currently working on a much bigger mission: figuring out how fast the cosmos is expanding.

New evidence suggests that the cosmos is not expanding at the same rate everywhere.

There is a difference in the rate of expansion of the universe as it is around us and observations made after the Big Bang.

NASA observes that something weird is going on in the cosmos based on Hubble data.

NASA notes that the study of how the universe grew and how rapidly it began decades ago in 1920, when measurements by Edwin P Hubble and Georges Lemaitre revealed that galaxies beyond our own were not stationary.

These galaxies are actually travelling away from us.

These galaxies were travelling at a non-uniform, increasing rate, according to Hubble.

The further a galaxy was from Earth, the faster it was moving away.

Since then, scientists have been attempting to comprehend the phenomenon and determine the pace of expansion.

However, now that Hubble data is available, it appears that the expansion is considerably faster than models expected.

Scientists are now awaiting data from the new James Webb Space Telescope, which will offer a more in-depth examination at the matter, as the new data kicks off a new review of our understanding of the universes expansion.

The Webb Space Telescope will extend on Hubbles work by showing these cosmic milepost markers at greater distances or sharper resolution than what Hubble can see, NASA said.

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Hubble Telescope: Something weird going on in universe - us.bolnews.com

Earlier this year, the single greatest site reliability engineering (SRE) lesson unfolded itself out in space. Last week we saw the very first, better-than-even-expected images from the James Webb Space Telescope or JWST.

After ten years of design and build on a $9 billion budget, this was an effort in testing 344 single points of failure all before deploying to production, with the distributed system a million miles and one month away.

Needless to say, there are a lot of reliability lessons to be learned from this endeavor. At his WTF is SRE talk last month, Robert Barron brought his perspective as an IBM SRE architect, amateur space historian, and a hobby space photographer to uncover the patterns of reliability that enabled this feat. And how NASA was able to trust its automation so much that itd release something with no hopes of fixing it. Its a real journey into observability at scale.

Its a great platform for demonstrating site reliability engineering concepts because this is reliability to the extreme, Barron said of the James Webb Space Telescope. If something goes wrong, if its not reliable, then it doesnt work. We cant just deploy it again. Its not something logical, its something physical that has to work properly and I think there are a lot of lessons and a lot of inspiration that we can take from this work into our day-to-day lives.

After 30 years of amazing photos from the Hubble Telescope, there was a demand for new business and technical capabilities, including to be able to see through and past clouds as they are created.

When designing the Webb telescope, the design engineers kicked off with the functional requirements, which in turn drove a lot of non-functional requirements. For instance, it needed to be much more powerful and larger than Hubble, but to achieve that it needed a significantly larger mirror. However, an operational constraint arose that the mirror is so large that it doesnt fit into any rocket, so it needed to be broken up into pieces. The non-functional requirement became to create a foldable mirror. A solution arose to break the mirror up into smaller hexagons, which can be aligned together to form a honeycomb-shaped mirror.

The second non-functional requirement of the JWST was to go beyond Hubble in not only seeing invisible light, but in seeing hot infrared light. But, to be accurate, the mirror needs to keep cold. Not just colder, but we need to be able to control the temperatures. Exactly. Because any variation and were going to look at something and think Oh, this is a star. This is a galaxy. Not thats just something there on Webb itself, which is slightly colder or warmer than it should be, Barron explained.

Unlike Hubble which orbits the Earth, Webb is unable to orbit because then its temperatures would vary greatly in sun and shade. Plus, it needs to be much farther away from earth than Hubble has ever gone. With this in mind, the controls and antennas face Earth and the telescope faces away with the honeycomb set of mirrors that reflect into a second set of mirrors which then sends the images back to the cameras, which are located in the middle of the honeycomb mirrors. Then behind it is a massive set of sunshades that work to control the temperature of the telescope.

When NASA decided back in 1995 to make this next-generation space telescope, the agency assumed itd cost about a billion dollars. In 2003, they started to design it, and they realized that its not just scaling up Hubble, we need technological breakthroughs the foldable mirrors, precise control of the temperature, the unfurling of the heat shields, and so on, said Barron. Over the next four years of high-level design, they moved the budget to $3.5 billion and planned on another billion for a decade of operations.

Then between 2007 and 2021, NASA dove into the design, build and test phase of what was named the James Webb Space Telescope.

Like good SREs we test and, because we have ten technological breakthroughs that we need to achieve, we have a lot of failures, Barron said. So we retest and fail, and retest and fail. And this takes a lot of time, and the project is nearly canceled many times. And eventually it costs $9.5 billion dollars just to build it. And that $1 billion that we thought would be enough to operate for 10 years is only going to be enough to operate for five years.

All things considered, the JWST was launched in December of last year, kicking off its operation, and what Barron referred to as pirouetting and ballet moves through space.

You can see that over a period of 13 days that the telescope, like a butterfly, opens up, spreads its wings, and started reporting home. And then starts going further away from Earth until it reaches the location where it will remain for the next decade, he explained. This journey took a total of 30 days.

As of the WTF is SRE event that Barron spoke at the end of April, the JWST was considered mid-deployment, before reaching production were doing the final tests before we can say that the system is working and can start giving actual scientific data.

During this deployment phase, there are so many components and pieces moving and changing, it uncovered many points of failure 344 to be exact.

Webb is famous for having over 300 single points of failure during this process of 30 days, each of which has to go perfectly, each of which if the fails, the entire telescope will not be able to function, Barron explained.

When those first exceptional photos came back, discovering new, fainter galaxies, was it luck or a feat of extreme site reliability engineering?

How did NASA reach the point where they could send $10 billion worth of satellite out into space without being able to fix anything without being able to reach out with an astronaut to say, Oh, I need to move something, I need to restart something, I need to do something manual. How can the system be completely fully automated? And can I trust that no dragons will come from outer space and do something to the telescope which will cause it to fail?

Robert Barron @FlyingBarron

You could say this is more than a leap of faith. That trust that NASA had in all this working properly, Barron believes, comes from its decades-long history of sending crafts into space, which is grounded in the values of:

Both the Voyager spacecraft that went to Jupiter, Saturn, Uranus, and Neptune and the Mars Rover were actually sets of identical twin crafts, in case one failed. Similarly, constellations of satellites work in tandem as fail-safes. This redundancy has long been embraced by NASA, but wasnt the option with the JWST price tag.

When redundancy is out, NASA next reaches for repairability. The Hubble Telescope has been repaired and upgraded multiple times for both fixes and preventive maintenance. And, according to Barron, 50% of the astronaut time on the International Space Station is actually spent on toil.

If the astronauts left the International Space Station, then, in a very short period of time, it would just break down and theyd be forced to send it back down into the atmosphere to burn up, he explained.

But, again, the non-functional requirement of repairability was also not an option for the Webb Telescope because it is floating far beyond the current capability of astronauts.

So the next step toward reliability came from building the JWST out of component architecture.

Barron went through a brief history of the Space Race between the Soviet Union and the U.S. from 1960 to 1988. He uncovered the pattern that redundancy didnt actually matter much because the failure modes were shared in both crafts each time, like an alloy wasnt durable enough or a launch was during a sandstorm. He did note that the Soviet space program chose not to publish their mistakes, so they were less likely than NASA to learn from them.

Redundancy is very good, but sometimes at a system level, it doesnt solve a problem because the problem is much wider, which Barron said happens to SREs as well. Kubernetes, for example, has componentization, redundancy and load balancing built-in, but that doesnt matter if the problem is with the DNS or an application bug. Often reliability demands more than simple redundancy.

The monolith Hubble was designed from the start with repairability and upgradeability in mind. With this repairability out of the picture, there had to be a lot more testing on Webb versus Hubble, for each single point of failure. For example, each mirror was a smaller component that could be realigned remotely. He analogized this to Kubernetes, where you want to allocate the right amount of CPU, memories, and resources available to each and every microservice.

In fact, Webb saw some observability trade-offs because it could only allow for so many selfie cameras to observe its own condition because adding more could affect the temperature and alter its observations.

Theres no doubt that the James Web Space Telescope SRE strategy has more stakes than any enacted on Earth. It still makes for a fantastic example of how site reliability engineering and observability needs vary within the context of circumstances. And that sometimes chaos engineering can only be performed before it goes into production.

Barron observed some of the JWSTs SRE strategy:

The JWST experiment is also a good reminder that, with fewer stakes than NASA, much more frequent, smaller deployment cadence, and with less than 100% uptime required, you can experiment more with redundancy, repairability and reliability to continuously improve your systems. Under ideally significantly less pressure.

As SREs, we dont want to aim for 100% availability. We want the right amount of availability, and we dont want to overspend neither resources nor budget in order to get there. We dont want to embrace too many new technologies for new products, Barron said. A lot of the lessons from Webb are what not to do.

Disclosure: The author of this article was a host of the WTF is SRE conference.

The New Stack is a wholly owned subsidiary of Insight Partners, an investor in the following companies mentioned in this article: Saturn.

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James Webb Space Telescope and 344 Single Points of Failure - thenewstack.io

James Webb Space Space Telescope may be humanity's future 'eye in the sky' but good ol' Hubble telescope still has a place in our hearts. Hubble has faithfuly relayed images of distant stars and galaxies to Earth for three decades. The space telescope does not cease to make us awestruck, amused and appreciate the endless beauty of the cosmos.

Latest image clicked by Hubble is such. While it may not be as exciting as a colliding galaxy, exploding star but this image tells us about our future.

The photo shows an elliptical galaxy called NGC 474. It is 100 million light-years away from Earth. It is about two and a half times larger than Milky Way Galaxy. The galaxy may not have a beautiful spiral structure like our own galaxy. It just looks like a wisp or smokey haze. But studying NGC 474 galaxy is vital because it gives us glimpses of our on future.

As much as we love our Milky Way Galaxy, it is on collision course with an even bigger galaxy. Andromeda galaxy is racing towards Milky Wayat an unimaginable speed.

We can breathe a little sigh of relief though because the galactic collision will take place billions of years from now. This collision of galaxies may not be as apocalyptic as movies have us believe. But immense gravities of Milky Way and Andromeda galaxies will tear material out from the cosmic dance partners. After a merger process that will last billions of years still, both galaxies will lose their spiral shapes and the resulting 'Milkdromeda' galaxy will have an elliptical shape just like NGC 474 which Hubble has clicked!

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Hubble clicks photo that shows future of Milky Way Galaxy - WION

The Crab Nebula, an iconic supernova remnant in our Milky Way galaxy, was photographed by the ESA's Herschel Space Observatory and the NASA/ESA Hubble Space Telescope in this composite image.

According to NASA, the Crab nebula is a wispy and filamentary cloud of gas and dust that was discovered by Chinese astronomers in 1054 as a remnant of a supernova explosion.

(Photo : ESA/Herschel/PACS/MESS Key Programme Supernova Remnant Team; NASA, ESA and Allison Loll/Jeff Hester (Arizona State University))

Space.comreported that the glow from cosmic dust contained in the nebula is shown by Herschel's observations, which are displayed in red. Hubble's view, in blue, shows the nebula's oxygen and sulfur gas.

A team of scientists using Herschel to study the nebula discovered that it contains far more dust than they anticipated - nearly a fourth of the mass of the Sun. The newer findings also revealed the presence of argon-based molecules, the first time such a molecule has been discovered in space.

Read More: #SpaceSnap: Hubble Space Telescope's Photo of Gas Clouds Inside NGC 1977 in The Running Man Nebula

The Herschel image is based on data collected at a wavelength of 70 microns with the Photoconductor Array Camera and Spectrometer (PACS) instrument, while the Hubble image is based on archival data from the Wide Field and Planetary Camera 2 (WFPC2).

"Herschel is a European Space Agency (ESA) mission with important NASA contributions, and Hubble is a NASA mission with important ESA contributions," NASA said.

Behold since the Crab Nebula isn't the only thing the Hubble Telescope has seen thus far. The following are some of the most fascinating images captured by the telescope:

(Photo : NASA, ESA, STScI, Julianne Dalcanton (Center for Computational Astrophysics / Flatiron Inst. and University of Washington); Image Processing: Joseph DePasquale (STScI))

NASA said that the image above is a "spectacular head-on collision between two galaxies fueled the unusual triangular-shaped star-birthing frenzy." On the right, the NGC 2445 is the more dazzling spiral galaxy, while the NGC 2444 lies on the left. Arp 143 is the collective name for them. [read more]

(Photo : NASA, ESA, K. Luhman and T. Esplin (Pennsylvania State University), et al., and ESO; Processing: Gladys Kober (NASA/Catholic University of America))

The Hubble Space Telescope image above depicts one of the Chameleon Cloud Complex's three segments. The photo was taken with Hubble's Advanced Camera for Surveys and the Wide Field and Planetary Camera 2. [read more]

(Photo : ESA/Hubble & NASA, B. Nisini)

A magnificent image of a laser-like jet of gas blasting from a very young star has been caught by the Hubble Space Telescope. Hubble's Wide Field Camera 3, one of the space telescope's five scientific instruments, captured the image. The Herbig-Haro object HH34, which is 1,250 light-years away from Earth, is depicted in this snapshot. [read more]

(Photo : NASA, ESA, and N. Da Rio (University of Virginia); Processing: Gladys Kober (NASA/Catholic University of America))NASAs Hubble Space Telescope captures another Flame Nebula.

The Hubble Space Telescope captured a stunning image of the Flame Nebula, officially known as NGC 2024. NGC 2024 is a large star-forming region around 1,400 light-years from Earth in the constellation Orion. [read more]

(Photo : NASA, ESA, and J. Bally (University of Colorado at Boulder); Processing: Gladys Kober (NASA/Catholic University of America))

Inside the Running Man nebula complex, the telescope captured breathtaking gas clouds. The Hubble Space Telescope's favorite subject to shoot is nebulae, and these photographs have helped scientists learn more about them. [read more]

Related Article: #SpaceSnap: Hubble Space Telescope Captures Amazing 'Space Triangle' Created by Colliding Galaxies

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#SpaceSnap The Alluring Crab Nebula Captured by the Hubble and Herschel Space Telescopes - iTech Post

This story was originally published by Undark and appears here as part of the Climate Desk collaboration.

Outer space isnt what most people would think of as an ecosystem. Its barren and frigid void isnt exactly akin to the verdant canopies of a rainforest or to the iridescent shoals that swim among coral cities. But if we are to become better stewards of the increasingly frenzied band of orbital space above our atmosphere, a shift to thinking of it as an ecosystem as part of an interconnected system of living things interacting with their physical environment may be just what we need.

Last month, in the journal Nature Astronomy, a collective of 11 astrophysicists and space scientists proposed we do just that, citing the proliferation of anthropogenic space objects. Thousands of satellites currently orbit the Earth, with commercial internet providers such as SpaceXs Starlink launching new ones at a dizzying pace. Based on proposals for projects in the future, the authors note, the number could reach more than a hundred thousand within the decade. Artificial satellites, long a vital part of the space ecosystem, have arguably become an invasive species.

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The band of orbital space just above our atmosphere is becoming so densely populated with satellites that it may threaten the practice of astronomy. Whereas the main source of light interference used to be the cities below, it is now increasingly the satellites above. These artificial stars can be a billion times brighter than the objects astronomers hope to study, and they emit radio waves that can interfere with telescopes. By some estimates, around one in 20 images from the Hubble Telescope are affected by the streaks of passing satellites. By 2030, the authors say, a third of Hubbles images could be impacted.

Yet the choice by the authors of the Nature Astronomy paper to call the orbital space around Earth an ecosystem reflects the fact that its not just astronomers who are affected by the recent infiltration of the night sky. Rather, the cluttering of orbital space is impacting the well-being of creatures both above the skies and below.

To begin with, there are the handful of astronauts at any given moment who call low-Earth orbit home and the plants, worms, and tardigrades that have been their playthings on the International Space Station. Space junk created by the rare but inevitable collisions between satellites which can travel faster than bullet speed is becoming a threat to that life. Last year, a five-millimetre hole was punctured in the International Space Stations robotic arm by debris of unknown origin.

But clutter in low-Earth orbit also threatens ways of life for entire communities of people here on the ground. The traditions and cosmologies of many Indigenous peoples, for example, are rooted in the movements of the stars. Polynesian sailors feats of navigation by starlight are unparalleled. The Palikur people of the Amazon see constellations as boats driven by shamans that bring rain and seasonal fish. The recent deluge of light pollution in our night skies is more than a headache to these and other Indigenous peoples, whose cosmologies may wither if the numbers of satellites arent kept in check. New artificial mega-constellations could mask those that have been relied on for millennia. (This issue may provide rare common ground between Indigenous peoples and professional astronomers, the latter of whom have historically been aligned with colonialism and courted controversy with the construction of new telescopes on sacred Indigenous lands.)

For many non-human animals, evidence suggests that a clear night sky might be a basic survival need. The hazy stripe of the Milky Way is used by dung beetles to navigate back to their burrows. Migratory birds, harbour seals, and some species of moths all use the movement of the stars as a compass too. Who knows how many other creatures might depend on a clear view of the night sky?

To protect the space ecosystem, we should treat it the way many aspire to treat our atmosphere and our oceans: as a global commons, a resource that lies beyond national, corporate, or individual ownership. The 1967 Outer Space Treaty took steps toward this ideal by recognizing that all nations have an equal interest in the exploration and use of outer space. Yet even that treaty establishes space as a resource humans can use for our own benefit. Thats like defining an ecosystem in terms of the natural capital it offers to humans, rather than recognizing the protection of habitats and biodiversity as an intrinsic good.

More apt would be to emphasize not the potential benefits that space provides to humans but rather the potential threats that humans pose to orbital space. In this view, overuse of the global commons by any one actor imposes a shared expense on us all. In our management of Antarctica, for example, preservation goes hand in hand with human activity on the continent. In this light, we shouldnt see low Earth orbit as the next frontier of capitalist extraction, but rather as an ecosystem to be protected one that, like other ecosystems, has limits and tipping points beyond which there is no return.

Some groups have started to open up conversations and build initiatives to this effect. The authors of the Nature Astronomy paper, for example, propose a space traffic footprint akin to a carbon footprint. And in February, the International Astronomical Union launched the Center for the Protection of the Dark and Quiet Sky from Satellite Constellation Interference. The centre, which will be co-hosted by the National Science Foundations NOIRLab and the Square Kilometer Array Observatory, aims to act as a hub of information and advocacy, bringing together stakeholders such as astronomers, ecologists, and Indigenous peoples alike. While much remains to be done, the issue is one of perspective as much as policy. It will take a shared commitment to the value of a clear night sky, and collaboration across diverse communities, to preserve orbital space for generations to come.

Unlike other ecosystems, the near-barrenness of the band of space just beyond our atmosphere is precisely what makes it unique and valuable. Preserving this transparent window grants us all access to what lies beyond.

Thomas Lewton is a science journalist who writes about astrophysics and the environment.

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Space is an ecosystem, too. And it's in peril - Canada's National Observer

(Image credit: NASA, ESA, and J. Tan (Chalmers University of Technology); Processing; Gladys Kober (NASA/Catholic University of America))

The Hubble Space Telescope has captured a stunning view of the Prawn Nebula floating through deep space.

The Prawn Nebula, formally known as IC 4628, is an emission nebula located 6,000 light-years from Earth, in the constellation Scorpius. Nebulas, or clouds of interstellar gas and dust, form following massive stellar explosions; in turn, this interstellar material gives life to new stars.

Stretching over 250 light-years wide, IC 4628 is believed to be a massive stellar nursery, where new stars are forming. Scientists classify it as an emission nebula because its gas has been energized, or ionized, by the radiation of nearby stars. That process produces electrons that re-emit the absorbed energy in the form of infrared light, according to a statement from NASA.

Full story: Hubble telescope captures stunning image of the star-forming Prawn Nebula

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The best Hubble Space Telescope images of all time!

China will launch its Xuntian Telescope to unravel cosmic mysteries while challenging the technology of NASA Hubble Telescope. Heres how.

NASA Hubble Space Telescope is set to get a major rival and that too from China. Hubble Telescope has spent 32 years and discovered new galaxies, stars, planets, comets, asteroids and a lot more. And it's still counting! Now, China is preparing to explore the universe and unravel the cosmic mysteries as it is set to launch its flagship space telescope soon. It is named as the Chinese Space Station Telescope (CSST), or Xuntian which means 'survey to heavens. Authorities in Beijing claimed that it will compete with NASA's Hubble Telescope, Chinese news agency Xinhua reported. However, it should be known that NASA has already launched and placed in orbit a brand new one recently and it is called the James Webb Space Telescope. It is much better than the Hubble Telescope and can see much farther back in time and space than Hubble can.

About Chinas Xuntian Telescope

China's flagship telescope, set to launch at the end of 2023, is aimed at exploring new insights into faraway galaxies, mysterious dark matter and dark energy, as well as the universe's past and future evolution. The Chinese Survey Space Telescope (CSST), also known as the Chinese Space Station Telescope (CSST) as well as the Xuntian Space Telescope, is a space-based optical observatory that allows astronomers to conduct sky surveys and capture a general map or photos of the sky. The CSST is a bus-sized facility with a three-story building's length.

How will China's flagship telescope challenge the NASA Hubble Telescope? In an exclusive interview with Xinhua, Liu Jifeng, deputy director of the National Astronomical Observatories of China (NAOC), explained that while the telescope's aperture is two metres, it has a field of view 350 times greater than Hubble's. On the contrary, NASA Hubble Space Telescope includes a 2.4-meter (94-inch) primary mirror, a smaller secondary mirror, and multiple recording devices that can detect visible light, ultraviolet light, and infrared light.

The CSST has a three-mirror anastigmat design that allows it to achieve exceptional image quality over a wide field of view. It's also a Cook-type off-axis telescope with no obstructions that, when correctly sampled, may reach superior precision in photometry, location, and shape measurements.

Beijing's space agency, the China National Space Administration (CNSA), has planned to place the telescope in the same orbit as its space station, Tiangong, which will be operational by the end of 2023. The Xuntian telescope will likely be the largest space observatory monitoring the cosmos in near-ultraviolet and visible light.

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China to beat NASA Hubble Space Telescope with its Xuntian Telescope - HT Tech

A galaxy is a group of astronomical objects that are bound gravitationally.

Think of planets and their natural satellites, comets and asteroids, stars and stellar remnants (such as neutron stars or white dwarfs), the interstellar gasses between them, cosmic dust, and cosmic rays, dark matter, etc. All these items are held together by the force of gravity that keeps them attracted to each other to form a system. This system is called a galaxy.

The universe is full of galaxies. Scientists have estimated different numbers of galaxies thanks to data collected by telescopes and interplanetary space probes, such as NASAs Hubble Telescope and NASAs New Horizon spacecraft. In 2020, they calculated that there were about two trillion galaxies in the observable universe.

As you can imagine, not all of these galaxies have the same characteristics, and they definitely dont look the same. Astronomers have recognized several types of galaxies according to their visual appearance. This galaxy morphological classification system, known as the Hubble sequence, or Hubble Tuning Fork, was invented by American astronomer Edwin Hubble in 1926, and its a significant part of the study of galaxy evolution.

The scheme divides galaxies into categories based on their shape. It is roughlydivided into elliptical galaxies and spiral galaxies. Hubble gave the elliptical galaxies numbers from zero to seven, with E0 galaxies having an almost round shape and E7 very stretched out and elliptical.

The spiral galaxies were given letters from "a" to "c," with "Sa" galaxies appearing more tightly wound and "Sc" galaxies more loosely wound. The spiral galaxies were furthersub-divided into normal spirals and barred spirals (which have a B in their designation), with barred spirals containing a bar of stars running through the central bulge.

Lenticular galaxies, designated S0, represent a transition between ellipticals and spirals.

Hubble also found that some galaxies did not fit into this classification system - they had odd shapes, were very small or very large, etc. These are termed irregular galaxies.

The Hubble system was later extended byGrard de Vaucouleurs, whoargued that ringsandlensesare also important structural components of spiral galaxies. De Vaucouleurs' system keeps Hubble's basic division of galaxiesbut introduces a more elaborate classification system for spiral galaxies based on the presence and types of bars, rings, and spiral arms.

Elliptical galaxies are the most abundant. They have spherical or oval shapes. They are not very active as they dont have much gas and cosmic dust to form new stars. Consequently, elliptical galaxies are mostly made of old stars with low mass, and they are not as bright as other types of galaxies. They tend to contain less gas and dust than spiral galaxies, which means fewer stars are born, and existing stars tend to be older, giving off more red light. But they are kind of brighter at the center where star density is greater and where there is most likely a supermassive black hole. Presumably, this black hole supplies elliptical galaxies with the force of gravity necessary to keep the system together.

Elliptical galaxies account for around one-third of all known galaxies and between 10-27% of galaxies in the Virgo Supercluster, a mass concentration of galaxies that encompass the Virgo Cluster and the Local Group, two galaxy groups that contain the Milky Way galaxy (our "home" galaxy) and the Andromeda galaxy, one of our closest neighbors.

There are two subtypes of elliptical galaxies based on their sizes:

Spiral galaxies are thought to be the most recurrent in our universe. Around 60% of all galaxies are thought to be spiral galaxies.

As their name indicates, these galaxies are spiral-shaped. They consist of a flat, rotating disk of stars, cosmic dust, and interstellar gas, which spins around a central bulge made up of older, dimmer stars.The bulge is believed to contain a supermassive black hole.

The disk of stars orbiting the bulge separates into arms that circle the galaxy. These spiral arms contain a wealth of gas and dust and younger stars that shine brightly before their often rapid demise.

The bulge is surrounded by a galactic halo made of older, dimmer stars that are spread through several globular clusters (spherical groups of stars).

It is not fully understood what process creates and maintains the spiral arms.These galaxies rotate differentiallyeverything orbits at the same speed, so the time it takes to complete a full rotation increases with distance from the center. This differential rotation also causes any disturbance in the disk to wind up into a spiral form. If this were the only process involved in creating the spiral, we would likely see galaxies with a large number of tightly wrapped spiral arms.But most spiral galaxies have between two and four main arms.

Researchers believe the spiral form is also affected bydensity waves, which travel through the disk and cause stars and gas to "pile up" at the crest.

Our galaxy, the Milky Way, has four spiral arms two major arms called Scutum-Centaurus and Perseus and two minor arms named Norma and Sagittarius. It also has a number of branches made of fragments of the main arms. The Sun is located in one of these branches off the Sagittarius arm, called the Orion Spur.

Barred spiral galaxies are spiral galaxies in which the arms do not stretch all the way to the center but connect with the ends of a bar-shaped center made of bright, young stars. According to a 2008 study by NASA, bars form when stellar orbits in a spiral galaxy divert from their path after a process of destabilization that is usually linked to the galaxys age and evolution.

The affected stars in the spirals begin to describe a more elongated orbit that stretches out the center of the galaxy, so it ends up looking like an extended bar. This bar structure channels interstellar gas inflows towards the center of the spiral galaxy, which fuels star formation.

Approximately half of the known spiral galaxies have bars. In fact, the Milky Way is officially classified as a barred spiral galaxy.

Lenticular galaxies often share characteristics with both elliptical and spiral galaxies.

They are called lenticular because they are in the shape of a lens. They can be compared to spiral galaxies in that they have a galactic bulge and a flat disk surrounding them. However, they do not have spiral arms or clearly-defined spiral arms. Therefore, they don't appear spiral-shaped.

The formation of lenticular galaxies is not clearly understood.One theory is that lenticular galaxies used to be spiral galaxies that have grown old and consumed most of their gas and cosmic dust. In fact, lenticular galaxies do not produce an important number of new stars because they have run out of matter to do so. As a result, they are made of mostly old stars, like elliptical galaxies. Another prominent theory is that lenticular galaxies are formed when two spiral galaxies collide.

Irregular galaxies are called this because they do not have a distinct regular shape, and therefore, they donot neatly fit into any of the Hubble categories.

They lack spiral arms and a nuclear galactic bulge, and overall, they tend to look very chaotic. Some astronomers believe that irregular galaxies were originally elliptical or spiral galaxies that suffered from structural alterations due to mergers and/or interactions with other galaxies.

This is likely the case with the Magellanic Clouds, two irregular dwarf galaxies that orbit the Milky Way and were probably affected by its gravitational force, which distorted them into their current irregular shape.

Many irregular galaxies appear to be older than spirals but younger than ellipticals, leading someastronomers to hypothesize that irregular galaxies may be in an in-between stage.

Irregular galaxies can also be classified as Irregular I (Irr I), which feature some structure but not enough to be classified as another type of galaxy, and Irregular II (Irr II), which does not have any kind of recognizable structure at all. There are alsodIrr (dwarf irregular) galaxies.

Irregular galaxies are most frequently small, and they can contain lots of gas and cosmic dust, as well as both old and young stars.

Peculiar galaxies are those which do not fit in any other category of the Hubble classification scheme as they are unusual in shape, size, and/or composition.

They are believed to be formed by the collision of two or more galaxies, whose gravitational forces are constantly interacting with each other. This is why many peculiar galaxies can also be called interacting galaxies. This is also why they have extremely unusual shapes, an elevated rate of star formation, and more than one active central nucleus.

Perhaps some of the most famous peculiar galaxies are the Antennae Galaxies, which are interacting with each other in the constellation Corvus and are expected to fully collide (and become one) in about 400 million years.

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How many types of galaxies are there in the universe? - Interesting Engineering

Shepard Price,Digital reporter

March 28, 2022

The Hubble Telescope depicted in an artist's rendering with Earth in the background

NASA will make an announcement Wednesday regarding a new observation from the Hubble Telescope the agency says is "one for the record books."

The Hubble Telescope, launched almost 32 years ago, has worked for decades to "reshape our understanding of the universe," NASA wrote in a press statement. Hubble's work stretches from exploring exoplanets to galaxies to measuring the expansion of the universe, which has won the multi-observatory team a Nobel Prize.

NASA promises that the latest result "creates an exciting area of research for Hubble's future work with NASA's newly-launched James Webb Space Telescope," which launched on Dec. 25. The Webb telescope is scheduled to begin observation in June.

Hubble is expected to remain operational at least well into the 2020's, NASA has stated. Hubble used to be serviced every few years, but that ended in 2011 when the space shuttle program was retired. The last servicing mission to Hubble was in 2009.

Shepard Price has a Master's degree in Journalism from the University of Texas and lives in St. Louis. They have been in journalism for more than four years.

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NASA to make announcement Wednesday regarding Hubble Telescope - The Edwardsville Intelligencer

Hubbles most magnificent images With investigations into everything from black holes to exoplanets, the Hubble Telescope has changed not only the face of astronomy but also our very sense of being in the universe. On the 30th anniversary of its launch into low-earth orbit, this updated edition of Expanding Universe presents 30 brand new images, unveiling more hidden gems from the Hubbles archives.

Ultra-high resolution and taken with almost no background light, these pictures have answered some of the most compelling questions of time and space while also revealing new mysteries, like the strange dark energy that sees the universe expanding at an ever-accelerating rate.

The collection is accompanied by an essay from photography critic Owen Edwards and an interview with Zoltan Levay, who explains how the pictures are composed. Veteran Hubble astronauts Charles F. Bolden, Jr. and John Mace Grunsfeld also offer their insights on Hubbles legacy and future space exploration.

Charles F. Bolden, Jr., Major General, USMC (Ret.), is a former Administrator of NASA, where he oversaw the completion of the International Space Station. He spent 14 years as a member of NASAs Astronaut Corps, and commanded and piloted the Space Shuttle Discovery on STS-31, which launched the Hubble Space Telescope into orbit.

Owen Edwards has written about photography for more than 30 years for numerous publications including American Photographer, New York Times Magazine, and Smithsonian.

John Mace Grunsfeld, PhD, is an astrophysicist and a NASA astronaut. He has flown five times on the Space Shuttle, including three Hubble servicing missions. He has served as the Associate Administrator for the Science Mission Directorate, the NASA Chief Scientist, and as the Deputy Director of the Space Telescope Science Institute.

Zoltan Levay is a retired principle science visuals developer at the Space Telescope Science Institute, where he worked with astronomers and communicators worldwide to publicize science results from NASA's Hubble Space Telescope.

Hardcover with fold-outs, 11.4 x 11.4 in., 5.44 lb, 260 pages

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Expanding Universe. The Hubble Space Telescope - Taschen