Universe Today

September 18, 2011April 26, 2016 by Jason Major

“Pluto-Killer” Sets Sights on Neptune

Infrared image of Neptune from Keck Observatory in Hawaii. Credit: Mike Brown/CalTech

[/caption]

The confessed (and remorseless) “Pluto Killer” Mike Brown has turned his gaze – and the 10-meter telescope at the Keck Observatory in Hawaii – on Neptune, our solar system’s furthest “official” planet. But no worries for Neptune – Mike isn’t after its planetary status… he’s taken some beautiful infrared images instead!

Normally only visible as a featureless blue speck in telescopes, Brown’s image of Neptune — along with its largest moon Triton — shows the icy gas giant in infrared light, glowing bright red and orange.

Brown’s initial intention was not just to get some pretty pictures of planets. The target of the imaging mission was Triton and to learn more about the placement of its methane, nitrogen and seasonal frosts, and this sort of research required infrared imaging. Of course, Neptune turned out to be quite photogenic itself.

“The big difference is doing the imaging in the infrared where methane absorbs most of the photons,” said Brown. “So the bright places are high clouds where the sunlight reflects off of them before it had a chance to pass through much of the atmosphere. Dark is clear atmosphere full of methane absorption.

“I just thought it was so spectacular that I should post it.”

No argument here, Mike!

Neptune, now officially the outermost planet in our solar system, is the fourth largest planet and boasts the highest wind speeds yet discovered — 1,250 mph winds scream around its frigid skies! Like the other gas giants Neptune has a system of rings, although nowhere near as extravagant as Saturn’s. It has 13 known moons, of which Triton is the largest.

With its retrograde orbit, Triton is believed to be a captured Kuiper Belt Object now in orbit around Neptune. Kuiper Belt Objects are Mike Brown’s specialty, as he is the astronomer most well-known for beginning the whole process that got Pluto demoted from the official planet list back in 2006.

SpaceX to Dock With ISS on Next Flight: NASA Maybe – Russia Nyet

Russia has again stated that doea not approve of SpaceX and NASA's plans to dock the next Dragon Spacecraft with the International Space Station. Image Credit: SpaceX

[/caption]

It is looking less likely that Space Exploration Technologies (SpaceX) will be allowed to dock the next of its Dragon Spacecraft to the International Space Station (ISS). Instead it is now looking like the Dragon will be allowed to only come close the orbiting outpost to test out many of the spacecraft’s key systems.

This comes from a statement issued by Vladimir Solovyov, head of the Russian segment of the ISS mission control center on Friday and posted on the Russian news site RIA Novosti. Up until now SpaceX has stated that they would launch the next Dragon Spacecraft atop one of the company’s Falcon 9 rockets on Nov. 30. It is unknown now whether-or-not the proposed docking will be allowed to take place.

889899052_Cnv38-X2 — SpaceX has had a string of successes - and failures - since its founding in 2002. Photo Credit: Alan Walters/awaltersphoto.com

In a company-prepared statement, SpaceX stated that the company had been working to fulfill all of the necessary requirements to allow SpaceX to become the first private firm to dock its spacecraft with the ISS. Russia, however, has repeatedly stated that it will not allow this. The rationale behind this stance is based on safety. According to Russia, a vehicle, which has only flown once, does not have the established, proven track record required for such operations.

Moreover both NASA and SpaceX stated that while a final determination has yet to be made – the private space firm has not been denied the opportunity to dock with the International Space Station. Thus leaving the flight’s status in a sort of limbo. This situation also highlights that the assorted international members involved on ISS – don’t always agree.

Russia's most recent attempt to launch its unmanned Progress Spacecraft ended in the loss of the spacecraft as well as its cargo. Photo Credit: RSC Energia

Many industry experts noted the irony of these statements given that the last Soyuz rocket failed, causing the destruction of the Progress spacecraft as well as the three tons of supplies that the spacecraft carried.

NewSpace firms themselves have acknowledged anomalies in their programs – including SpaceX. Blue Origin recently lost one of its test vehicles. Apparently the rocket went off of its predicted flight path and range safety was forced to destroy the vehicle.

112309Cygnus02 — Orbital Science's Cygnus Spacecraft is one of the other vehicles being developed under the COTS program. Image Credit: Orbital Sciences Corporation

Under the initial Commercial Orbital Transportation Services (COTS) agreement SpaceX was supposed to launch the Demo 2 mission, which would have completed COTS Milestone 19 (the mission scheduled for this November) two years ago. Similarly, milestones 20-22 were scheduled to be accomplished by the first quarter of 2010.

COTS is a NASA-funded program, designed to coordinate delivery of both astronauts as well as cargo to the ISS by privately-owned companies. COTS – was announced in January of 2006, under the Bush Administration. As it stands currently, SpaceX is the frontrunner under this contract which also includes Orbital Sciences Corporation.

September 18, 2011April 13, 2022 by Ken Kremer

Space Shuttle Enterprise Unveiled 35 Years Ago to Star Trek Fanfare

The Shuttle Enterprise. In 1976, NASA's space shuttle Enterprise rolled out of the Palmdale manufacturing facilities and was greeted by NASA officials and cast members from the 'Star Trek' television series. From left to right they are: NASA Administrator Dr. James D. Fletcher; DeForest Kelley, who portrayed Dr. "Bones" McCoy on the series; George Takei (Mr. Sulu); James Doohan (Chief Engineer Montgomery "Scotty" Scott); Nichelle Nichols (Lt. Uhura); Leonard Nimoy (Mr. Spock); series creator Gene Rodenberry; an unnamed NASA official; and, Walter Koenig (Ensign Pavel Chekov). Credit: NASA

[/caption]

‘Enterprise’, the first of NASA’s Space Shuttle orbiters to be assembled, was unveiled 35 Years ago on Sept. 17, 1976 to the soaring theme song and fanfare of the immortal science fiction television series – ‘Star Trek’. Members of the original cast (photo above) were on hand for the celebratory rollout at the Rockwell International manufacturing plant in Palmdale, California.

Today, the Enterprise is housed as the centerpiece at the Smithsonian’s National Air & Space Museum (NASM) Udvar-Hazy Annex in Chantilly, Virginia.

Check out these webcams for live views of shuttle Enterprise at NASM from the front and aft.

Space Shuttle Enterprise on display at the Smithsonian’s National Air & Space Museum Udvar-Hazy Annex in Chantilly, Virginia

NASA originally selected ‘Constitution’ as the orbiter’s name – in honor of the U.S. Constitution’s Bicentennial . That was until avid fans of ‘Star Trek’ mounted a successful letter writing campaign urging the White House to select the name ‘Enterprise’ – in honor of the popular TV shows starship of exploration. The rest is history.

Many scientists and space enthusiasts found inspiration from Star Trek and were motivated to become professional researchers by the groundbreaking science fiction show.

Space Shuttle Enterprise on display as the centerpiece at the Smithsonian’s National Air & Space Museum Udvar-Hazy Annex in Chantilly, Virginia. Credit: NASA

Enterprise was a prototype orbiter, designated as OV-101, and not built for spaceflight because it lacked the three space shuttle main engines necessary for launch and the thermal protection systems required for reentry into the Earth’s atmosphere.

Enterprise did however play a very key role in preparing NASA’s other shuttles for eventual spaceflight. The orbiter was tested in free flight when it was released from a Boeing 747 Shuttle Carrier Aircraft for a series of five critical approach and landing tests in 1977.I was fortunate to see Enterprise back in 1977 on top of a 747 during a cross country stop near the Johnson Space Center.

Enterprise in free flight during approach and landing test in 1977

In 1979 Enterprise was mated to an External Tank and a pair of Solid Rocket Boosters for several weeks of fit checks and procedural test practice in launch configuration at Launch Complex 39 at NASA’s Kennedy Space Center in Florida.

These efforts helped pave the way for the first ever flight of a space shuttle by her sister orbiter ‘Columbia’ on the STS-1 mission by John Young and Bob Crippen. Columbia blasted off on April 12, 1981 on a gutsy 54 hour test flight.

In 1984, the Enterprise was ferried to Vandenberg Air Force Base for similar pad configuration checks at Space Launch Complex- 6 (SLC-6) for what was then planned to be the shuttle’s west coast launch site. All California launches were cancelled following the destruction of Space Shuttle Challanger in Jan 1986.

After three decades of flight, the Space Shuttle Era came to a historic end with the majestic predawn touchdown of Space Shuttle Atlantis on Jul 21, 2011. The STS-135 mission was the Grand Finale of NASA’s three decade long Shuttle program.

Following the retirement of all three remaining shuttle orbiters, Enterprise will soon be moved to her new permanent home at the Intrepid Air, Sea and Space Museum in New York City to make way for NASA’s new gift of Space Shuttle Discovery.

First Appearance of Enterprise
Space shuttle Enterprise made its first appearance mated to supportive propellant containers/boosters cluster, as it was rolled from the Vehicle Assembly Building at Kennedy Space Center en route to the launch pad, some 3.5 miles away, on May 1, 1979. Enterprise underwent several weeks of fit and function checks on the pad in preparation for STS-1, on which its sister craft Columbia took astronauts John Young and Robert Crippen into space for a 54-hour test mission. Credit: NASA

Space Shuttle Enterprise at Space Launch Complex 6 (SLC-6 ) at Vandenberg Air Force Base, on February 1, 1985. Credit: Tech. Sgt. Bill Thompson/USAF

Read Ken’s continuing features here about Discovery, Endeavour and Atlantis
Send Ken your pictures of Enterprise to publish at Universe Today.

September 18, 2011April 13, 2022 by Ken Kremer

Space Spectacular — Rotation Movies of Vesta

Viewing the South Pole of Vesta. This image obtained by Dawns framing camera and shows the south pole of the giant asteroid Vesta. Scientists are discussing whether the circular structure that covers most of this image originated by a collision with another asteroid, or by internal processes early in the asteroid's history. Images in higher resolution from Dawn's lowered orbit might help answer that question. The image was recorded from a distance of about 1,700 miles (2,700 kilometers). The image resolution is about 260 meters per pixel. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Take us into orbit Mr. Sulu!

The Dawn science team has released two spectacular rotation movies of the entire globe of the giant asteroid Vesta. The flyover videos give the distinct impression that you are standing on the bridge of the Starship Enterprise and gazing at the view screen as the ship enters orbit about a new planet for the first time and are about to begin an exciting new journey of exploration and discovery of the body you’re looking at below.

Thanks to NASA, DLR, ASI and Dawn’s international science and engineering team, we can all join the away team on the expedition to unveil Vesta’s alluring secrets.

Click the start button and watch protoplanet Vesta’s striking surface moving beneath from the perspective of Dawn flying above – in the initial survey orbit at an altitude of 2700 kilometers (1700 miles). Vesta is the second most massive object in the main asteroid belt and Dawn’s first scientific conquest.

Another video below was compiled from images taken earlier on July 24, 2011 from a higher altitude after Dawn first achieved orbit about Vesta and revealed that the northern and southern hemispheres are totally different.

The array of images in the videos was snapped by Dawn’s framing camera which was provided by the German Aerospace Center (DLR). The team then created a shape model from the images, according to Dr. Carol Raymond, Dawn’s Deputy Principal Investigator from NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

The shape model will aid in studying Vesta’s strikingly diverse features of mountains, ridges, valley’s, scarps, cliffs, grooves, craters, even a ‘snowman’ and much more.

Notice that not all of Vesta is illuminated – because it’s northern winter at the asteroid. Vesta has seasons like Earth and the northern polar region in now in perpetual darkness. Data is collected over the day side and radioed back to Earth over the night side.

“On Vesta right now, the southern hemisphere is facing the sun, so everywhere between about 52 degrees north latitude and the north pole is in a long night,” says Dr. Rayman, Dawn’s Chief Engineer from JPL. “That ten percent of the surface is presently impossible to see. Because Dawn will stay in orbit around Vesta as together they travel around the sun, in 2012 it will be able to see some of this hidden scenery as the seasons advance.”

Another movie highlight is a thorough look at the gigantic south pole impact basin. The circular feature is several hundred miles wide and may have been created by a cosmic collision eons ago that excavated massive quantities of material and basically left Vesta lacking a south pole.

[/caption]

The massive feature was discovered in images taken by the Hubble Space Telescope several years ago and mission scientists have been eager to study it up close in a way that’s only possible from orbit. Dawn’s three science instruments will investigate the south pole depression in detail by collecting high resolution images and spectra which may reveal the interior composition of Vesta.

Dawn entered the survey orbit on Aug. 11 and completed seven revolutions of 69 hours each on Sept. 1. It transmitted more than 2,800 pictures from the DLR framing camera covering the entire illuminated surface and also collected over three million visible and infrared spectra from the VIR spectrometer – provided by ASI, the Italian Space Agency. This results exceeded the mission objectives.

The Dawn spacecraft is now spiraling down closer using its ion propulsion system to the next mapping orbit – known as HAMO – four times closer than the survey orbit and only some 680 km (420 miles) above the surface.

Read Ken’s continuing features about Dawn
3 D Alien Snowman Graces Vesta
NASA Unveils Thrilling First Full Frame Images of Vesta from Dawn
Dawn Spirals Down Closer to Vesta’s South Pole Impact Basin
First Ever Vesta Vistas from Orbit – in 2D and 3D
Dawn Exceeds Wildest Expectations as First Ever Spacecraft to Orbit a Protoplanet – Vesta
Dawn Closing in on Asteroid Vesta as Views Exceed Hubble
Dawn Begins Approach to Asteroid Vesta and Snaps First Images
Revolutionary Dawn Closing in on Asteroid Vesta with Opened Eyes

September 18, 2011January 14, 2016 by Fraser Cain

Amazing Timelapse Video from the Space Station

Science educator James Drake built this amazing timelapse video from the perspective of the International Space Station as it flew over North and South America. He created this video by downloading a series of 600 photographs that were available online at the Gateway to Astronomy Photograph of Earth, and then stitching them together into a complete video. You can see more of James work at his blog: infinity imagined.

September 17, 2011December 24, 2015 by Steve Nerlich

Astronomy Without A Telescope – The Edge Of Significance

A two hemisphere spherical mapping of the cosmic microwave background. Credit: WMAP/NASA.

[/caption]

Some recent work on Type 1a supernovae velocities suggests that the universe may not be as isotropic as our current standard model (LambdaCDM) requires it to be.

The standard model requires the universe to be isotropic and homogeneous – meaning it can be assumed to have the same underlying structure and principles operating throughout and it looks measurably the same in every direction. Any significant variation from this assumption means the standard model can’t adequately describe the current universe or its evolution. So any challenge to the assumption of isotropy and homogeneity, also known as the cosmological principle, is big news.

Of course since you are hearing about such a paradigm-shifting finding within this humble column, rather than as a lead article in Nature, you can safely assume that the science is not quite bedded down yet. The Union2 data set of 557 Type 1a supernovae, released in 2010, is allegedly the source of this latest challenge to the cosmological principle – even though the data set was released with the unequivocal statement that the flat concordance LambdaCDM model remains an excellent fit to the Union2 data.

Anyhow, in 2010 Antoniou and Perivolaropoulos ran a hemisphere comparison – essentially comparing supernova velocities in the northern hemisphere of the sky with the southern hemisphere. These hemispheres were defined using galactic coordinates, where the orbital plane of the Milky Way is set as the equator and the Sun, which is more or less on the galactic orbital plane, is the zero point.

The galactic coordinate system. Credit: thinkastronomy.com

Antoniou and Perivolaropoulos’ analysis determined a preferred axis of anisotropy – with more supernovae showing higher than average velocities towards a point in the northern hemisphere (within the same ranges of redshift). This suggests that a part of the northern sky represents a part of the universe that is expanding outwards with a greater acceleration than elsewhere. If correct, this means the universe is neither isotropic nor homogeneous.

However, they note that their statistical analysis does not necessarily correspond with statistically significant anisotropy and then seek to strengthen their finding by appealing to other anomalies in cosmic microwave background data which also show anisotropic tendencies. So this seems to be a case of looking at number of unrelated findings with common trends – that in isolation are not statistically significant – and then arguing that if you put all these together they somehow achieve a consolidated significance that they did not possess in isolation.

More recently, Cai and Tuo ran much the same hemispherical analysis and, not surprisingly, got much the same result. They then tested whether these data favoured one dark energy model over another – which they didn’t. Nonetheless, on the strength of this, Cai and Tuo gained a write up in the Physics Arxiv blog under the heading More Evidence for a Preferred Direction in Spacetime – which seems a bit of a stretch since it’s really just the same evidence that has been separately analysed for another purpose.

It’s reasonable to doubt that anything has been definitively resolved at this point. The weight of current evidence still favours an isotropic and homogeneous universe. While there’s no harm in mucking about at the edge of statistical significance with whatever limited data are available – such fringe findings may be quickly washed away when new data comes in – e.g. more Type 1a supernovae velocity measures from a new sky survey – or a higher resolution view of the cosmic microwave background from the Planck spacecraft. Stay tuned.

Further reading:
– Antoniou and Perivolaropoulos. Searching for a Cosmological Preferred Axis: Union2 Data Analysis and Comparison with Other Probes.
– Cai and Tuo. Direction Dependence of the Deceleration Parameter.

September 17, 2011December 24, 2015 by Tammy Plotner

Stellar Superburst: Neutron Star Blows Away Model

A detailed rendering of the neutron star surface and what the surface might look like during the explosion. Credit: NASA/Dana Berry

[/caption]Imagine an event so catastrophic that it pours more energy out in three hours than the Sun does in a hundred years. Now imagine it a reality. In a study done by Yuri Cavecchi et al. (2011), they’ve witnessed a neutron star outburst which has put all computer modeling for thermodynamic explosions on extreme objects back to square one.

Apparently a strong magnetic field around accreting pulsar IGR J17480-2446 is the culprit for some areas of the star to ignite in the extreme. X-ray binary IGR J17480-2446, as a general rule, should be about one and a half times the mass of the Sun confined in an area of about 25km. This creates a strong gravitational field which extracts gas from its orbiting companion. In turn, this collects on the surface of the primary and kindles a fast, high-energy thermonuclear reaction. In a perfect scenario, this reaction would be spread over the surface evenly, but for some reason in about 10% of case studies some areas burn brighter than others. Just why this happens is a true enigma.

In order to better understand the phenomena, theoretical models were created to test out spin rates. They suggest that rapid rotation stops the burning material from spreading uniformly – much like the Coriolis force develops terrestrial hurricanes. Another hypothesis proposes these conflagrations ride on global-scale waves where one side stays cool and dim as it rises, while the other remains hot and bright. But just which one is viable in the case of this strange pulsar?

“We explore the origin of Type I burst oscillations in IGR J17480–2446 and conclude that they are not caused by global modes in the neutron star ocean. We also show that the Coriolis force is not able to confine an oscillation-producing hot-spot on the stellar surface.” says lead author Yuri Cavecchi (University of Amsterdam, the Netherlands). “The most likely scenario is that the burst oscillations are produced by a hot-spot confined by hydromagnetic stresses.”

What makes the astronomers think this way? One explanation might be the strange properties of J17480 itself. While it obeys the rules when it comes to forming bright patches during thermonuclear events, it break them when it comes to spin rates. Why does this particular star only rotate about 10 times per second when the next slowest does it at 245? This is where the magnetic field theory comes into play. Perhaps when explosions occur, it’s held in place by this invisible, yet powerful, force.

“More theoretical work is needed to confirm this, but in the case of J17480 it is a very plausible explanation for our observations”, says Cavecchi. Co-author Anna Watts further explains their new models – while interesting – might not account for all non-uniform events seen in similar situations. “The new mechanism may only work in stars like this one, with magnetic fields that are strong enough to stop the flame front from spreading. For other stars with this odd burning behavior, the old models might still apply.”

Original Information Source: Netherlands Research School for Astronomy. For Further Reading: Implications of burst oscillations from the slowly rotating accreting pulsar IGR 17480-2446 in the globular cluster Terzan 5.

September 17, 2011December 24, 2015 by Ken Kremer

Cassini’s Majestic Saturn Moon Quintet

A quintet of Saturn's moons come together in the Cassini spacecraft's field of view for this portrait. From left to right: Janus, Pandora, Enceladus, Mimas and Rhea. Credit: NASA/JPL-Caltech/Space Science Institute

[/caption]

Check out this gorgeous new portrait of a Saturnian moon quintet taken by Earths’ emissary – NASA’s Cassini Orbiter. The moons are majestically poised along a backdrop of Saturn’s rings, fit for an artist’s canvas.

Janus, Pandora, Enceladus, Mimas and Rhea are nearly lined up (from left to right) in this view acquired by Cassini at a distance of approximately 684,000 miles (1.1 million kilometers) from Rhea and 1.1 million miles (1.8 million kilometers) from Enceladus.

The newly released image was taken by Cassini’s narrow angle camera on July 29, 2011. Image scale is about 4 miles (7 kilometers) per pixel on Rhea and 7 miles (11 kilometers) per pixel on Enceladus.

Cassini will stage a close flyby of Enceledus – Satarn’s geyser spewing moon – in about two weeks, swooping within 99 km

Moon Facts from JPL:
Janus (179 kilometers, or 111 miles across) is on the far left. Pandora (81 kilometers, or 50 miles across) orbits between the A ring and the thin F ring near the middle of the image. Brightly reflective Enceladus (504 kilometers, or 313 miles across) appears above the center of the image. Saturn’s second largest moon, Rhea (1,528 kilometers, or 949 miles across), is bisected by the right edge of the image. The smaller moon Mimas (396 kilometers, or 246 miles across) can be seen beyond Rhea also on the right side of the image.

This view looks toward the northern, sunlit side of the rings from just above the ring plane. Rhea is closest to Cassini here. The rings are beyond Rhea and Mimas. Enceladus is beyond the rings.

The simple graphic below shows dozens of Saturn’s moons – not to scale. So far 62 have been discovered and 53 have been officially named.

Saturn’s moons. Click on link below to learn more about each moon. Credit: NASA/JPL

Learn more about Saturn’s moons at this link

List of Saturn’s officially named moons:
Aegaeon, Aegir, Albiorix, Anthe, Atlas, Bebhionn, Bergelmir, Bestla, Calypso, Daphnis, Dione, Enceladus, Epimetheus, Erriapus, Farbauti, Fenrir, Fornjot, Greip, Hati, Helene, Hyperion, Hyrrokkin, Iapetus, Ijiraq, Janus, Jarnsaxa, Kari, Kiviuq, Loge, Methone, Mimas, Mundilfari, Narvi, Paaliaq, Pallene, Pan, Pandora, Phoebe, Polydeuces, Prometheus, Rhea, Siarnaq, Skadi, Skoll, Surtur, Suttung, Tarqeq, Tarvos, Telesto, Tethys, Thrym, Titan and Ymir.

September 16, 2011December 24, 2015 by Tammy Plotner

Even Small Galaxies Can Have Big Black Holes

Astronomers detected supermassive black holes in 28 distant, low-mass galaxies, including the four shown in these Hubble Space Telescope images. Image credit: A. Koekemoer, Space Telescope Science Institute.

[/caption]

The Hubble Space Telescope has done it again. By utilizing a slitless grism, the Wide Field Camera 3 has uncovered evidence that supermassive black holes are right at home in some very small galaxies. Apparently these central black holes began their life when their host galaxies were first forming!

“It’s kind of a chicken or egg problem: Which came first, the supermassive black hole or the massive galaxy? This study shows that even low-mass galaxies have supermassive black holes,” said Jonathan Trump, a postdoctoral researcher at the University of California, Santa Cruz. Trump is first author of the study, which has been accepted for publication in the Astrophysical Journal.

It’s another cosmic conundrum. As we’ve learned, large galaxies are host to central supermassive black holes and many of them are the AGN variety. But the real puzzle is why do some smaller galaxies contain them when most do not? By taking a closer look at dwarf galaxies some 10 billion light-years away, astronomers are reaching back in time to when the Universe was about an estimated quarter of its current age.

“When we look 10 billion years ago, we’re looking at the teenage years of the universe. So these are very small, young galaxies,” Trump said.

If your mind is still wondering what a “slitless grism” is, then wonder no more. It’s part of Hubble’s WFC3 infrared camera that provides spectroscopic information. Thanks to highly detailed information on the different wavelengths of light, the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) team could achieve separate spectra from each sector of the candidate galaxies and identify emissions from black hole sources.

“This is the first study that is capable of probing for the existence of small, low-luminosity black holes back in time,” said coauthor Sandra Faber, University Professor of astronomy and astrophysics at UC Santa Cruz and CANDELS principal investigator. “Up to now, observations of distant galaxies have consistently reinforced the local findings–distant black holes actively accreting in big galaxies only. We now have a big puzzle: What happened to these dwarf galaxies?”

It’s possible they are forerunners of the massive galaxies we see today. “Some may remain small, and some may grow into something like the Milky Way,” Trump said. But this theory is a juxtaposition in itself. According to Faber, “To become big galaxies today, the dwarf galaxies would have to grow at a rate much faster than standard models predict. If they remain small, then nearby dwarf galaxies should also have central black holes. There might be a large population of small black holes in dwarf galaxies that no one has noticed before.”

But these distant little dwarfs aren’t quiet – they are actively forming new stars. According to Trump, “Their star formation rate is about ten times that of the Milky Way. There may be a connection between that and the active galactic nuclei. When gas is available to form new stars, it’s also available to feed the black hole.”

But the Hubble wasn’t the only instrument interested in the 28 small galaxy studies. The team also employed x-ray data acquired by NASA’s Chandra X-ray Observatory. To help refine their information on such small, faint objects, the data was combined to improve the signal-to-noise ratio.

“This is a powerful technique that we can use for similar studies in the future on larger samples of objects,” Trump said. “Together the compactness of the stacked OIII spatial profile and the stacked X-ray data suggest that at least some of these low-mass, low-metallicity galaxies harbor weak active galactic nuclei.”

Original Story Source: University of Santa Cruz News. For Further Reading: A CANDELS WFC3 Grism Study of Emission-Line Galaxies at z~2: A Mix of Nuclear Activity and Low-Metallicity Star Formation.

September 16, 2011April 13, 2022 by Ken Kremer

Dramatic Videos of Station Undocking, Gorgeous Earth Descent and Soyuz Touchdown by Russian American Trio

Soyuz Lands with the Moon as backdrop. Credit: NASA/Bill Ingalls

Video Caption: Soyuz Trio Lands in Kazakhstan – The Soyuz spacecraft carrying NASA astronaut Ron Garan and his fellow Expedition 28 flight engineers returned safely to Earth on Sept. 16 with a landing on the steppe of Kazakhstan. Garan and cosmonauts Andrey Borisenko, and Alexander Samokutyaev had been on the International Space Station since April 6. Their journey home was delayed just over a week by the failure of the Progress 44 cargo craft to reach the station. Remaining on the orbiting laboratory is NASA’s Mike Fossum and his two Expedition 28/29 colleagues, Russian Sergei Volkov, and Satoshi Furukawa of the Japanese Aerospace Exploration Agency

Check out this collection of dramatic videos of the departure, descent and safe touchdown of the trio of Russian and American space flyers aboard the Soyuz TMA 21 spacecraft in the remote steppes of Kazakhstan on Sept. 16, 2011.

The first video above is a compilation of all the key events from the Soyuz spacecraft undocking from the International Space Station (ISS) to landing and gives the complete picture. Be sure to watch the Soyuz flying away like a bird with the gorgeous Earth in the background. Observe the crew being extracted like fish from the capsule.

The rest of the videos are shorter and break down the story to focus on the key individual events of the crews remaining final hours aboard the station and in space.

This video records the “Change of Command” as Mike Fossum takes over the helm of the ISS

Video Caption: NASA’s Fossum Given ISS Command – In a ceremony conducted 230 miles above the Earth on Sept. 14, the “helm” of the International Space Station was handed over by Expedition 28 Commander Andrey Borisenko to NASA astronaut, Mike Fossum, who takes command of the orbiting laboratory on Expedition 29.

Hatch Closure and Bidding Farewell

Video Caption: Hatch Closes as Soyuz Crew Bids Farewell – The Expedition 28 crew of Soyuz Commander Alexander Samokutyaev, NASA Flight Engineer Ron Garan and off-going station Commander Andrey Borisenko said their goodbyes to the remaining residents of the International Space Station before closing the hatch on their vehicle and preparing to undock for their return home to Earth on Sept. 16

This video highlights the ISS undocking sequence

Video Caption: Soyuz Undocks from ISS – The Soyuz TMA-21 spacecraft that’ll carry Commander Alexander Samokutyaev, NASA Flight Engineer Ron Garan and off-going station Commander Andrey Borisenko back to Earth undocks from the International Space Station and begins its return journey home.

[/caption]

Read Ken’s Soyuz landing story for further details:
Expedition 28 Soyuz Crew Lands Safely in Kazakhstan