Our Picks of Best Space and Astronomy Images from 2011

First Ever Portrait of the International Space Station and docked Shuttle Endeavour from Soyuz capsule. This image of the International Space Station and the docked Space Shuttle Endeavour, flying at an altitude of 220 miles was taken by Expedition 27 crew member Paolo Nespoli from the Soyuz TMA-20 following its undocking on May 23, 2011. It is the first-ever image of a space shuttle docked to the International Space Station. Endeavour at left. European ATV cargo carrier at right. Credit: NASA/Paolo Nespoli

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2011 was a picturesque year! The year brought us new discoveries, a new supernova, the end of an era in human spaceflight, and much more. Here’s a look back at some of the best images we’ve posted on Universe Today in 2011, listed in no particular order:

Above, is one of the first-ever images of a space shuttle docked to the International Space Station. The images were taken by ESA astronaut Paolo Nespoli on May 23, 2011 through a window inside the Soyuz TMA-20 vehicle as he and two crewmates were departing the ISS for their return trip to Earth. See the entire gallery of images of this event here.


Astrophoto: Supernova PTF11kly in M101 by Rick Johnson
Supernova PTF11kly in M101. Credit: Rick Johnson

A new supernova showed up in 2011 in the Pinwheel galaxy, and skywatchers around the world tried to capture it. Amateur astronomer Rick Johnson submitted this image for our new “Astrophoto” feature this year on Universe Today. Called the SN PTF11kly, the new Type Ia supernova was spotted by Caltech’s Palomar Transient Factory (PTF) survey in the M101, and is located 21 million light years away. You can see the supernova marked in the southern part of the galaxy.

Atlantis launches one last time on July 8, 2011. Credit: Alan Walters (awaltersphoto.com) for Universe Today.

2011 saw the end of an era: the space shuttle program is now history. Universe Today photographer Alan Walters captured this stunning view of the last shuttle launch ever. Read our articles about the final launch and landing of the space shuttle era.

A portion of the Lagoon nebula imaged by the Gemini South telescope with the Gemini Multi-Object Spectrograph. Credit: Julia I. Arias and Rodolfo H. Barbá Departamento de Física, Universidad de La Serena (Chile), and ICATE-CONICET (Argentina).

A gorgeous new look at the “Southern Cliff” in the Lagoon Nebula from the Gemini South Observatory.

Saturns moons and rings, in color. Credit: NASA / JPL / SSI. Edited by Jason Major. Click for larger version.

The Cassini spacecraft continues to crank out spectacular images, and this stunning image of a “flash mob” of moons strung along Saturn’s rings is just an example.

ATV2 (Johannes Kepler) as it departs the ISS against the backdrop of Earth. Credit: NASA/Ron Garan

Real image or from a movie? The ATV-2 Johannes Kepler looks like an X-Wing fighter from Star Wars as it departed from the International Space Station.

A new image from the HiRISE camera on the Mars Reconnaissance Orbiter shows an ethereal landscape near Mars north pole. Credit: NASA/HiRISE team

Incredible landscapes are specialties of the HiRISE camera on the Mars Reconnaissance Orbiter, and this observation shows dune gullies laced with beautiful swirls of tracks left by dust devils. Just like on Earth, dust devils move across the Martian surface and expose the underlying darker material, creating a striking view.

A new image from ESO of the reflection nebula Messier 78. Credit: ESO and Igor Chekalin

Here’s a “Hidden Treasure” from the European Southern Observatory, from the astrophotography competition where amateurs create images from unused ESO data. In this new image of Messier 78, brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light and creating what is called a reflection nebula.

Series of transits taken on May 20, 22 and 23, 2011 from different areas of France, showing variations of orientation of the ISS with Endeavour docked. On May 23, the ISS passes besides a sunspot which is larger than the Earth. Credit: Thierry Legault

This series of images is just an example of the great work by award-winning French astrophotographer Thierry Legault. During shuttle Endeavour’s final mission, Legault traveled through Germany, France and Spain to find clear skies and good seeing to capture the shuttle’s voyage to the International Space Station. See more incredible images here.

The 'Rock Garden' at the rim of Endeavour Crater on Mars as seen by the Opportunity rover. Credit: NASA/JPL/Caltech, color by Stu Atkinson

The Opportunity rover is now exploring Endeavour Crater and this color view of shows a stunning landscape on Mars. This view of a Red Planet “rock garden” is the colorized handiwork of Stu Atkinson, a member of Unmanned Spaceflight and author of the Road to Endeavour blog. This is actually an ejecta field of rocks thrown about after the impact that created this huge crater, and has been an exciting region for the MER scientists to explore.

Dense filaments of gas in the IC5146 interstellar cloud. This image was taken by ESA’s Herschel space observatory at infrared wavelengths 70, 250 and 500 microns. Stars are forming along these filaments. Credits: ESA/Herschel/SPIRE/PACS/D. Arzoumanian (CEA Saclay) for the “Gould Belt survey” Key Programme Consortium.

Its true there is no sound in empty interstellar space, but the Herschel space observatory has observed the cosmic equivalent of sonic booms. Filaments like this have been sighted before by other infrared satellites, but they have never been seen clearly enough to have their widths measure.

A huge and spectacular prominence eruption on the Sun, June 7, 2011. Credit: NASA/Solar Dynamics Observatory

On June 7, 2011 an amazingly massive and spectacular event took place on the Sun: a huge prominence eruption, marked by a solar flare and release of energetic particles. It was an event that was heretofore unseen on the Sun, but the Solar Dynamics Observatory saw it all.

A view of a recent aurora from the ISS. Credit: NASA

With the Sun’s activities ramping up, we saw more aurorae. What better place to see them than from the International Space Station? This view taken by astroanut Mike Fossum shows a stunning aurora, with two Russian vehicles docked to the station in the foreground.

The star cluster NGC 2100 in the Large Magellanic Cloud. Credit: ESO

A brilliant cluster of stars in the Large Magellanic Cloud, open cluster NGC 2100 shines brightly, competing with the nearby Tarantula Nebula for bragging rights in this image from ESO’s New Technology Telescope (NTT).

Martian Vista from Opportunity nearing Endeavour Crater on Sol 2678 - August 2011 Large ejecta blocks from the nearby, small Odyssey crater are visible in the middle, foreground and are Opportunity’s next science target in this photo mosaic taken 2 martian days ago on Sol 2678 (Aug. 6). Opportunity is now less than 400 feet from the foothills of Endeavour Crater and will soon make first landfall at Spirit Point - off to the left. At Endeavour, Opportunity will investigate the oldest minerals deposits she has ever visited from billions of years ago and which may hold clues to environments that were potentially habitable for microbial life. This photo mosaic shows portions of the discontinuous crater rim – Cape Tribulation at right. Mosaic Credit: NASA/JPL/Cornell/Marco Di Lorenzo/Kenneth Kremer

Universe Today’s Ken Kremer helped bring this stunning image of the hills around Endeavour Crater to light, as the Opportunity Rover headed towards the crater in August.

Astrophoto: Moon Covers Venus by Kevin Jung
Moon Covers Venus. Credit: Kevin Jung

Another amateur astrophoto shows an occultation of Venus by the Moon, taken by Kevin Jung.

X-ray Image of Tycho's Supernova Remnant. (NASA/CXC/Rutgers/K.Eriksen et al.)

The Chandra X-Ray Observatory took a brand new, deep look inside the Tycho Supernova Remnant, providing a nearly three-dimensional view of the iconic space object.

Comet Lovejoy by Barry Armstead
Comet Lovejoy. Image Credit: Barry Armstead

And just the past several days southern skywatchers have been treated to the beautiful sights of Comet Lovejoy — which was also seen from the International Space Station. Go take a look!

These are just a sampling of the great images we’ve seen in 2011. Here’s to more great views in 2012!

Why Do We Live in Three Dimensions?

The puzzling universe. Image credit: NASA/courtesy of nasaimages.org

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Day to day life has made us all comfortable with 3 dimensions; we constantly interact with objects that have height, width, and depth. But why our universe has three spatial dimensions has been a problem for physicists, especially since the 3-dimensional universe isn’t easily explained within superstring theory or Big Bang cosmology. Recently, three researchers have come up with an explanation.  

The history of the universe starting the with the Big Bang. Image credit: grandunificationtheory.com

Most astronomers subscribe to Big Bang cosmology, the model that proposes that the universe was born from the explosion of an infinitely tiny point. The theory is supported by observations of the cosmic microwave background and the abundance of certain naturally occurring elements. But Big Bang cosmology is at odds with Einstein’s theory of general relativity – general relativity doesn’t allow for any situation in which the whole universe is one tiny point, which means this theory alone can’t explain the origin of the universe.

The incompatibility between general relativity and Big Bang cosmology has stumped cosmologists. But almost 40 years ago, superstring theory arose as a possible unifying theory of everything.

A visualization of strings. Image credit: R. Dijkgraaf.

Superstring theory suggests that the four fundamental interactions among elementary particles – electromagnetic force, weak interaction, strong interaction, and gravity – are represented as various oscillation modes of very tiny strings. Because gravity is one of the fundamental forces, superstring theory includes an explanation of general relativity. The problem is, superstring theory predicts that there are 10 dimensions – 9 spatial and one temporal. How does this work with our 3 dimensional universe?

Superstring theory has remained little more than a theory for years. Investigations have been restricted to discussing models and scenarios since performing the actual calculations have been incredibly difficult. As such, superstring theory’s validity and usefulness have remained unclear.

But a group of three researchers, associate professor at KEK Jun Nishimura, associate professor at Shizuoka University Asato Tsuchiya, and project researcher at Osaka University Sang-Woo Kim, has succeeded in generating a model of the universe’s birth based on superstring theory.

Using a supercomputer, they found that at the moment of the Big Bang, the universe had 10 dimensions – 9 spatial and 1 temporal – but only 3 of these spatial dimensions expanded.

This "baby picture" of the universe shows tiny variations in the microwave background radiation temperature. Hot spots show as red, cold spots as dark blue.Credit: NASA/WMAP Science Team

The team developed a method for calculating matrices that represent the interactions of strings. They used these matrices to calculate how 9 dimensional space changes over time. As they moved further back in time, they found that space is extended in 9 directions, but at one point only 3 directions start to expand rapidly.

In short, the 3 dimensional space that we live in can result from the 9 original spatial dimensions string theory predicts.

This result is only part of the solution to the space-time dimensionality puzzle, but it strongly supports the validity of superstring theory. It’s possible, though, that this new method of analyzing superstring theory with supercomputers will lead to its application towards solving other cosmological questions.

 Source: The mechanism that explains why our universe was born with 3 dimensions.

James Webb Mirrors Pass Deep-Freeze Exams

The James Webb Space Telescope mirrors have completed deep-freeze tests and are removed from the X-ray and Cryogenic test Facility at Marshall Space Flight Center. Credit: Emmett Given, NASA Marshall

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The last of the 21 mirrors for the James Webb Space Telescope have come out of deep freeze – literally! – and are now approved for space operations, a major milestone in the development of the next generation telescope that’s being hailed as the “successor to Hubble.”

“The mirror completion means we can build a large, deployable telescope for space,” said Scott Willoughby, vice president and Webb program manager at Northrop Grumman Aerospace Systems. “We have proven real hardware will perform to the requirements of the mission.”

The all-important mirrors for the Webb telescope had to be cryogenically tested to make sure they could withstand the rigors and extreme low temperatures necessary for operating in space. To achieve this, they were cooled to temperatures of -387F (-233C) at the X-ray and Cryogenic Test Facility at Marshall Space Flight Center.

When in actual use, the mirrors will be kept at such low temperatures so as not to interfere with deep-space infrared observations with their own heat signatures.

JWST engineers anticipate that, with such drastic cooling, the mirrors will change shape. The testing proved that the mirrors would achieve the shapes needed to still perform exactly as expected.

“This testing ensures the mirrors will focus crisply in space, which will allow us to see new wonders in our universe,” said Helen Cole, project manager for Webb Telescope mirror activities.

Planned for launch in 2018, the JWST will be the premier observatory of the next decade, serving thousands of astronomers worldwide. It will study every phase in the history of the Universe, ranging from the first luminous glows after the Big Bang to the formation of solar systems capable of supporting life on Earthlike planets.

Learn more about the James Webb Space Telescope here.

Top Astronomy Events Coming Up in 2012

Stargazing Credit: http://twitter.com/VirtualAstro

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As 2011 is drawing to a close, the festive season is here and many of us are winding down and looking forward to the holidays. But this is a great time to look ahead to 2012 and pencil into our calendar and diaries the top astronomical events we don’t want to miss next year.

2012 is going to be a great year for astronomy observing, with some rare and exciting things taking place and a good outlook with some of the regular annual events.

So what top wonders should we expect to see and what will 2012 bring?

Conjunction of Venus and Jupiter

Venus & Jupiter Conjunction Credit: Anthony Arrigo UtahSkies.org

On March 15th the Planets Venus and Jupiter will be within 3 degrees and very close to each other in the early evening sky. This will be quite a spectacle as both planets are very bright (Venus being the brightest) and the pair will burn brightly together like a pair of alien eyes watching us after the Sun sets.

This conjunction (where planets group close together as seen from Earth) will be a fantastic visual and photographic opportunity, as it’s not often you get the brightest Planets in our Solar System so close together.

Transit of Venus

Transit of Venus Credit: Australian Space Alliance

For many, the transit of Venus is the year’s most anticipated astronomical event and it takes place on June 5th – 6th. The Planet Venus will pass between the Earth and the Sun and you will see Venus (a small black circle) slowly move across, or “transit” the disc of the Sun.

Transits of Venus are very rare and only a few have been witnessed since the dawn of the telescope. Be sure not to miss this very rare event as the next one isn’t visible for over another 100 years from now in 2117 and the next after that is in 2125.

The full transit of Venus in 2012 will be visible in North America, the northwest part of South America, Western Pacific, North East Asia, Japan, Australia and New Zealand. Other parts of the world will see a partial transit such as observers in the UK, who will only be able to see the last part of the transit as the Sun rises.

First contact will be at 22:09 UT and final contact will be at 04:49 UT

Take note! You have to use the right equipment for viewing the Sun, such as eclipse glasses, solar filters, or projection through a telescope. Never ever look directly at the Sun and never look at it through a normal telescope or binoculars – You will be permanently blinded! The transit of Venus will be a very popular event, so contact your local astronomy group and see if they are holding an event to celebrate this rare occasion.

Meteor Showers

Don't Miss the Major 2012 Meteor Showers Credit: Shooting Star Wallpapers

2011 was a poor year for meteor showers due to the presence of a largely illuminated Moon on all of the major showers; this prevented all but the brightest meteors being seen.

In contrast 2012 brings a welcome respite from the glare of the Moon as it gives little or no interference with this year’s major showers. The only other issue left to contend with is the weather, but if you have clear skies on the evenings of these celestial fireworks, you are in for a treat.

  • The Quadrantid Meteor Shower peak is narrow and just before dawn on January 4th this shower is expected to have a peak rate (ZHR) of around 80 meteors per hour.
  • The Perseid Meteor Shower peak is fairly broad with activity increasing on the evenings of the August 9th and 10th with the showers peak on the morning of the 12th. Perseids are the most popular meteor shower of the year as it tends to be warm and the shower has very bright meteors and fireballs, with rates of 100+ an hour at its peak.
  • The Geminid Meteor Shower is probably the best meteor shower of the year with high rates of slow bright meteors. The peak is very broad and rates of 100+ meteors per hour can be seen. The best time to look out for Geminids is on the evenings of the 12th to 14th December, but they can be seen much earlier or later than the peak.

If you want to find out more and enjoy the meteor showers of 2012, why not join in with a meteorwatch and visit meteorwatch.org

Jupiter and the Moon

Occultation of Jupiter by the Moon on July 15th as seen from Southern England Credit: Adrian West

European observers are in for a very rare treat as the Moon briefly hides the planet Jupiter on the morning of July 15th. This “lunar occultation” can be seen from southern England and parts of Europe at approximately 1:50am UT (dependant on location) and the planet re-emerges from the dark lunar limb at approximately 3:10am UT.

This is a great chance to watch this rare and bright event, and it will also be a fantastic imaging opportunity.

Annular Eclipse

Annular Eclipse Credit: Kitt Peak Observatory

American observers will have treat on May 20th with an annular eclipse of the Sun. The eclipse will be visible from many western US states and a partial eclipse visible from most of North America.

Because the Moon’s orbit is not a perfect circle and is slightly elliptical, it moves closer and further away from us slightly in its orbit by 13% and on July 15th it is at its furthest point away from the Earth as it passes in front of the Sun.

Normally the Moon covers the entire disc of the Sun and creates a total solar eclipse, but because the Moon is at its furthest point in its orbit on the 15th, we get an annular eclipse, where we can still see a ring of bright light around the Sun, but we don’t get totality.

The eclipse starts roughly at 6:20pm local time for the Western US states and lasts for four and a half minutes.

As mentioned earlier; never, ever look at the Sun without proper protection such as eclipse glasses or filters for equipment! This can damage your eyes and permanently blind you. This is the same for cameras; the sensitive chips inside can be damaged.

The World Not Ending

End Of The World

Finally we get to December 21st, in which astronomy-minded folks will celebrate the solstice. But in case you haven’t heard, some have prophesied the end of the world, saying the Mayan calendar ends. This has been the subject of much discussion, comedy and media coverage, and it has even been made into films.

Will the Antichrist press the red button and will there be the Rapture? Will the Earth reverse its magnetic poles, or will we get wiped out by a solar flare, rogue comet or asteroid?

Nope, probably not. You can read our entire series which explains why this whole 2012 end-of-the-world craze is complete hokum.

All I know is 2012 is going to be a great year for astronomy with some very interesting, rare events taking place, with many more regular events to see, as well.

I’m sure it’s not going to end.

 

Earth’s Other Moons

Saturn's moons Rhea and Dione as seen by the Cassini spacecraft. Could this be a future view from Earth? Image credit: NASA/JPL/Space Science Institute

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In the fall of 2006, observers at the Catalina Sky Survey in Arizona found an object orbiting the Earth. At first, it looked like a spent rocket stage — it had a spectrum similar to the titanium white paint NASA uses on rocket stages that end up in heliocentric orbits. But closer inspection revealed that the object was a natural body. Called 2006 RH120, it was a tiny asteroid measuring just a few metres across but it still qualified as a natural satellite just like the Moon. By June 2007, it was gone. Less than a year after it arrived, it left Earth’s orbit in search of a new cosmic companion.

Now, astrophysicists at Cornell are suggesting that 2006 RH120 wasn’t an anomaly; a second temporary moon is actually the norm for our planet.

Temporary satellites are a result of the gravitational pull of Earth and the Moon. Both bodies pull on one another and also pull on anything else in nearby space. The most common objects that get pulled in by the Earth-Moon system’s gravity are near Earth objects (NEOs) — comets and asteroids are nudged by the outer planets and end up in orbits that bring them into Earth’s neighbourhood.

Near Earth object Eros, the type of object that could be a second satellite. Image credit: NASA

The team from Cornell, astrophysicists Mikael Granvik, Jeremie Vaubaillon, Robert Jedicke, has modeled the way our Earth-Moon system captures these NEOs to understand how often we have additional moons and how long they stick around.

They found that the Earth-Moon system captures NEOs quite frequently. “At any given time, there should be at least one natural Earth satellite of 1-meter diameter orbiting the Earth,” the team said. These NEOs orbit the Earth for about ten months, enough time to make about three orbits, before leaving.

Luckily, and very interestingly, this discovery has implication well beyond academic applications.

Knowing that these small satellites come and go but that one is always present around the Earth, astronomers can work on detecting them. With more complete information on these bodies, specifically their position around the Earth at a given time, NASA could send a crew out to investigate. A crew wouldn’t be able to land on something a few metres across, but they could certainly study it up close and gather samples.

Close up image of asteroid 243 Ida. Image credit: NASA/courtesy of nasaimages.org

Proposals for a manned mission to an asteroid have been floating around NASA for years. Now, astronauts won’t have to go all the way out to an asteroid to learn about the Solar System’s early history. NASA can wait for an asteroid to come to us.

If the Cornell team is right and there is no shortage of second satellites around the Earth, the gains from such missions increases. The possible information about the solar system’s formation that we could obtain would be amazing, and amazingly cost-efficient.

Source: Earth Must Have Another Moon, Astronomers Say

First Look at a Black Hole’s Feast


A true heart of darkness lies at the center of our galaxy: Sagittarius A* (pronounced “A-star”) is a supermassive black hole with the mass of four million suns packed into an area only as wide as the distance between Earth and the Sun. Itself invisible to direct observation, Sgr A* makes its presence known through its effect on nearby stars, sending them hurtling through space in complex orbits at speeds upwards of 600 miles a second. And it emits a dull but steady glow in x-ray radiation, the last cries of its most recent meals. Gas, dust, stars… solar systems… anything in Sgr A*’s vicinity will be drawn inexorably towards it, getting stretched, shredded and ultimately absorbed (for lack of a better term) by the dark behemoth, just adding to its mass and further strengthening its gravitational pull.

Now, for the first time, a team of researchers led by Reinhard Genzel from the Max-Planck Institute for Extraterrestrial Physics in Germany will have a chance to watch a supermassive black hole’s repast take place.

Continue reading “First Look at a Black Hole’s Feast”

A Refreshing Idea! Vote for Enabling City Kids to See Starry Skies

Now here’s a refreshing idea: create a “dark sky oasis” in suburban locations where city-dwellers can gather to see the stars and learn about the night sky. The International Dark-Sky Association has proposed a project to bring access to the starry night to urban areas through the creation of Suburban Outreach Sites. To make this project a reality, the IDA needs your help, and all it takes is a click of your mouse. Every year the Pepsi Refresh project gives away tens of thousands of dollars in grants to improve communities. The IDA is competing for one of these grants and needs your vote!

A Suburban Outreach Site could be built right in your community. These will be safe, public places where people can gather to enjoy the night sky. Scott Kardel, the Public Affairs Director for the IDA told Universe Today that Suburban Outreach Sites will be easily accessible from US cities.

“They will offer a good place to stargaze (relative to the area) and will hold free events to bring celestial wonders to the young and old,” Kardel said. “Suburban Outreach Sites will educate the next generation of astronomers to keep looking up, and inspire them to use better lighting to save energy, conserve natural resources, and help wildlife.”

These sites will be created through a partnership between IDA and local astronomy clubs.

If funded the Pepsi Refresh grant will help IDA designate Suburban Outreach Sites around the USA.

“IDA will coordinate action with our Chapters and astronomy clubs to select a safe place with a beautiful nighttime atmosphere,” Kardel said. “IDA will create ‘fresh’ programming ideas and event coordination, and even offer free materials on how to dim city lights and bring back the stars.”

Projects are chosen by popular vote and people can vote every day in the month of December to help IDA bring the night sky.

You can support the IDA by voting here: http://www.refresheverything.com/citystarparks

New Submillimetre Camera Sheds Light on the Dark Regions of the Universe

A composite image of the Whirlpool Galaxy (also known as M51). The green image is from the Hubble Space Telescope and shows the optical wavelength. The submillimetre light detected by SCUBA-2 is shown in red (850 microns) and blue (450 microns). The Whirlpool Galaxy lies at an estimated distance of 31 million light years from Earth in the constellation Canes Venatici Credit: JAC / UBC / Nasa

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The stars and faint galaxies you see when you look up at the night sky are all emitting light within the visible light spectrum — the portion of the electromagnetic spectrum we can see with our unaided eyes or through optical telescopes. But our galaxy, and many others, contain huge amounts of cold dust that absorbs visible light. This accounts for the dark regions.

A new camera recently unveiled at the James Clerk Maxwell Telescope (JCMT) in Hawaii promises to figuratively shed light on this dark part of the universe. The SCUBA-2 submillimetre camera (SCUBA in this case is an acronym for Submillimetre Common-User Bolometer Array) can detect light at lower energy levels, allowing astronomers to gather data on these dark areas and ultimately learn more about our universe and its formation. 

Light is measurable; its intensity or brightness is measured by photons while colour is measured by the energy of the photons. Red photons have the least energy and violet photons have the most energy. This can also be thought of in terms of wavelengths. Light at longer wavelengths have less energy and light at shorter wavelengths have more energy. This continues beyond the visible light spectrum. As electromagnetic waves get shorter, we get ultraviolet light, x-rays, and gamma rays. As wavelengths get longer, we get infrared light, submillimetre light, and finally radio waves.

Panoramic view of the entire near-infrared sky reveals the distribution of galaxies beyond the Milky Way. Image credit: Thomas Jarrett, IPAC/Caltech.

On the longer end of the electromagnetic spectrum, infrared and radio telescopes have been around for decades helping astronomers understand more about the universe. But this is only part of the picture. The cold dust that absorbs the visible light to create the dark regions seen through optical telescopes is actually absorbing the light’s energy and reemitting it at longer wavelengths in the submillimetre region.

The first submillimetre camera, SCUBA, was designed and constructed at the Royal Observatory in Edinburgh in collaboration with the University of London. In 1997, it was up and running at the JCMT. Observations of submillimetre wavelengths are typically harder to gather — it takes a long time to image a small portion of the sky in this region. Nevertheless, submillimetre observations have already revealed a previously unknown population of distant, dusty galaxies as well as images of cold debris discs around nearby stars. This latter finding could be an indication of the presence of planetary systems.

A team of astronomers has recently developed the camera SCUBA-2 that can probe the submillimetre region with increased speed and much greater detail. But it’s a touchy instrument. Director of the JCMT Professor Gary Davis explains that for SCUBA-2 to detect extremely low energy radiation in the submillimetre region, “the instrument itself needs to be [extremely cold]. The detectors… have to be cooled to only 0.1 degree above absolute zero [–273.05°C], making the interior of SCUBA-2 colder than anything in the Universe that we know of!”

The infant Universe as imaged in the radio wavelength spectrum. Image Credit: NASA/WMAP Science Team.

The camera is a huge step in observational astronomy. Director of the United Kingdom Astronomy Teaching Centre Professor Ian Robson likened the technological leap between early sub-millimetre cameras and SCUBA-2 to the difference between wind-on film cameras and modern digital technology. “It is thanks to the ingenuity and abilities of our scientists and engineers that this immense leap in progress has been achieved,” he said.

Dr Antonio Chrysostomou, Associate Director of the JCMT, explains that SCUBA-2’s first task will be to carry out a series of surveys throughout the sky, mapping sites of star formation within our Galaxy, as well as planet formation around nearby stars. It will also survey our galactic neighbours and look into deep space to sample the youngest galaxies in the Universe. This latter task will be critical in helping astronomers understand how galaxies have evolved since the Big Bang.

The SCUBA-2 camera is housed on the 15 metre (about 50 foot) diameter JCMT situated close to the summit of Mauna Kea, Hawaii, at an altitude of 4092 metres (about 13,425 feet). It is typically used to study our Solar System, interstellar dust and gas, and distant galaxies.

Source: Revolutionary New Camera Reveals Dark Side of the Universe

 

The James Clerk Maxwell Telescope. Image credit: www.jach.hawaii.edu

 

 

Astronomers Find the Most Supermassive Black Holes Yet

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For years, astronomer Karl Gebhardt and graduate student Jeremy Murphy at The University of Texas at Austin have been hunting for black holes — the dense concentration of matter at the centre of galaxies. Earlier this year, they made a record-breaking discovery. They found a black hole weighing 6.7 billion times the mass of our Sun in the centre of the galaxy M87.

But now they shattered their own record. Combining new data from multiple observations, they’ve found not one but two supermassive black holes that each weigh as much as 10 billion Suns.

“They just keep getting bigger,” Gebhardt said.

An artist's impression of the black hole at the centre of the M87 galaxy. Image credit: Gemini Observatory/AURA illustration by Lynette Cook

Black holes are made of extremely densely packed matter. They produce such a strong gravitational field that even light cannot escape. Because they can’t be seen directly, astronomers find black holes by plotting the orbits of stars around these giant invisible masses. The shape and size of these stars’ orbits can determine the mass of the black hole.

Exploding stars called supernovae often leave behind black holes, but these only weigh as much as the single star. Black holes billions of times the mass of our Sun have grown to be so big. Most likely, an ordinary black hole consumed another, captured huge numbers of stars and the massive amount of gas that they contain, or be the result of two galaxies colliding. The larger the collision, the more massive the black hole.

The supermassive black holes Gebhardt and Murphy have found are at the centres of two galaxies more than 300 million light years from Earth. One weighing 9.7 billion solar masses is located in the elliptical galaxy NGC 3842, the brightest galaxy in the Leo cluster of galaxies 320 million light years away in the direction of the constellation Leo. The other is as large or larger and sits in the elliptical galaxy NGC 4889, the brightest galaxy in the Coma cluster about 336 million light years from Earth in the direction of the constellation Coma Berenices.

Each of these black holes has an event horizon — the point of no return where nothing, not even light can escape their gravity — 200 times larger than the orbit of Earth (or five times the orbit of Pluto). That’s a mind-boggling 29,929,600,000 kilometres or 18,597,391,235 miles. Beyond the event horizon, each has a gravitational influence that extends over 4,000 light years in every direction.

The illustration shows the relationship between the mass of a galaxy's central black hole and the mass of its central bulge. Recent discoveries of supermassive black holes may mean that the black holes in all nearby massive galaxies are more massive than we think. This could signal a change in our understanding of the relationship between a black hole and its surrounding galaxy. Image credit: Tim Jones/UT-Austin after K. Cordes & S. Brown (STScI)

For comparison, the black hole at the centre of our Milky Way Galaxy has an event horizon only one-fifth the orbit of Mercury — about 11,600,000 kilometres or 7,207,905 miles. These supermassive black holes are 2,500 times more massive than our own.

Gebhardt and Murphy found the supermassive black holes by combining data from multiple sources. Observations from the Gemini and Keck telescopes revealed the smallest, innermost parts of these galaxies while data from the George and Cynthia Mitchell Spectrograph on the 2.7-meter Harlan J. Smith Telescope revealed their largest, outmost regions.

Putting everything together to deduce the black holes’ mass was a challenge. “We needed computer simulations that can accommodate such huge changes in scale,” Gebhardt said. “This can only be done on a supercomputer.”

But the payoff doesn’t end with finding these massive galactic centre. The discovery has much more important implications. It “tells us something fundamental about how galaxies form” Gebhardt said.

These black holes could be the dark remnants of previously bright galaxies called quasars. The early universe was full of quasars, some thought to have been powered by black holes 10 billion Solar masses or more. Astronomers have been wondering where these supermassive galactic centres have since disappeared to.

Gebhardt and Murphy might have found a key piece in solving the mystery. Their two supermassive black holes might shed light on how black holes and their galaxies have interacted since the early universe. They may be a missing link between ancient quasars and modern supermassive black holes.

Source: McDonald Observatory Press Release.

Where Have All the Quasars Gone?