And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, let Fraser know if you can be a host, and he’ll schedule you into the calendar.
Finally, if you run a space-related blog, please post a link to the Carnival of Space. Help us get the word out
Meridiani Planum on Mars, at 15:00 local Mars time on May 2. Credit: NASA/JPL/Cornell University
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The New York Times Lens Blog came up with a great idea: They called it “A Moment in Time,” and asked people everywhere to take a picture on May 2, 2010 15:00 UTC and submit it, to share the variety and complexity of life on our world. Emily Lakdawalla from the Planetary Society saw this and thought, “Why limit it to Earth?” she wrote on the Planetary Blog. “What about Mars? What will Opportunity be doing at 15:00 U.T.C. on May 2?” Emily approached Jim Bell, planetary scientist at Cornell University and lead for the rovers’ Pancam team, who was immediately enthusiastic about the idea of having Opportunity take an image to submit to the “Moment in Time” project.
“My immediate reaction when Emily suggested the idea was ‘Cool!'” Bell told Universe Today. “My second reaction was to wonder whether we’d be able to take the photo at the right time, given the low power situation that Opportunity is in right now. Then my third through tenth reactions were ‘Cool!'”
“Two worlds, one sun: while humans’ lives unfolded on Earth, the Mars Exploration Rover Opportunity paused in its southward trek and captured this photomosaic. Dusty, reddish-brown sand dunes stretch to the horizon in a view taken around 15:00 local Mars time on May 2.”
Getting the image from Mars, though was not just as easy as pulling out a camera and taking a picture like people on Earth can do.
“The process of acquiring the image was perhaps just a bit more challenging than “normal” on the rover project,” said Bell, who asked us to remember–lest we all get jaded–how incredibly complex and amazing it is *whenever* we take images with robots on another planet!), — “because we were aiming for a specific time of day, and to try to get the data downlinked on that same day, very soon after taking the data. However, the rover engineering and science teams were very excited about participating in this global photo event, and that support was critical in helping to make it happen.”
Bell added that the image turned out to be a really lovely shot. The MarsDial (sundial) visible at the bottom of the image on Opportunity is engraved with the words “Two Worlds, One Sun” to mark the unity of Earth and Mars as part of the same solar system.
The timing was “a bit of a fudge” Emily admitted. “Our appointed hour would have been too late for Opportunity in midwinter. Besides, the data began arriving from Mars close to 15:00 U.T.C., so that’s when humans were first able to see the view.”
But the Lens blog folks thought, too, it was a really great idea and decided not to disqualify the picture.
I asked Emily if doing having this image taken at her request was even better than having a request approved for an image from HiRISE, with the “HiWISH” program (public suggestions for the HiRISE camera on the Mars Reconnaissance Orbiter). “It was kind of a HiWish with the rovers!” she said with a smile. “Of course the rover image wouldn’t have happened if the whole rover team wasn’t excited about participating. But it’s important to remind people that those rovers, and all the other spacecraft, and all the people who support them, are out there working hard every day to bring back the data.”
Indeed – wonderful idea, Emily, and great execution on the rover team’s part, making the Mars rovers even more endearing to us Martian wannabes here on Earth.
This artist's illustration (left) shows a close-up view of the Sculptor Wall, which is comprised of galaxies along with the warm-hot intergalactic medium (WHIM). Credit: Illustration: NASA/CXC/M.Weiss; Spectrum: NASA/CXC/Univ. of California Irvine/T. Fang et al.
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From a Chandra press release:
Scientists have used NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton to detect a vast reservoir of gas lying along a wall-shaped structure of galaxies about 400 million light years from Earth. In this artist’s impression, a close-up view of the so-called Sculptor Wall is depicted. Spiral and elliptical galaxies are shown in the wall along with the newly detected intergalactic gas, part of the so-called Warm Hot Intergalactic Medium (WHIM), shown in blue. This discovery is the strongest evidence yet that the “missing matter” in the nearby Universe is located in an enormous web of hot, diffuse gas.
The X-ray emission from WHIM in this wall is too faint to be detected, so instead a search was made for absorption spectrum of light from a bright background source by the WHIM, using deep observations with Chandra and XMM. This background source is a rapidly growing supermassive black hole located far beyond the wall at a distance of about two billion light years. This is shown in the illustration as a star-like source, with light traveling through the Sculptor Wall towards the Earth. The relative location of the background source, the Sculptor Wall, and the Milky Way galaxy are shown in a separate plot, where the view instead looks down on the source and the Wall from above.
An X-ray spectrum of the background source is given in the inset, where the yellow points show the Chandra data and the red line shows the best model for the spectrum after including all of the Chandra and XMM data. The dip in X-rays towards the right side of the spectrum corresponds to absorption by oxygen atoms in the WHIM contained in the Sculptor Wall. The characteristics of the absorption are consistent with the distance of the Sculptor Wall as well as the predicted temperature and density of the WHIM. This result gives scientists confidence that the WHIM will also be found in other large-scale structures.
This result supports predictions that about half of the normal matter in the local Universe is found in a web of hot, diffuse gas composed of the WHIM. Normal matter — which is different from dark matter — is composed of the particles, such as protons and electrons, that are found on the Earth, in stars, gas, and so on. A variety of measurements have provided a good estimate of the amount of this “normal matter” present when the Universe was only a few billion years old. However, an inventory of the nearby Universe has turned up only about half as much normal matter, an embarrassingly large shortfall.
30 Dor #016. Illustration Credit: NASA, ESA, and Z. Levay (STScI) Science Credit: NASA, ESA, C. Evans (Royal Observatory Edinburgh), N. Walborn (STScI), and ESO
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In an astronomical version of “Biggest Loser” meets “Survivor,” a heavy weight star has been kicked out of its stellar nursery. This huge runaway star is rushing away from its birthplace at more than 402,336 kilometers per hour (250,000 miles an hour), and it likely was ejected by a group of even larger sibling stars. The future outlook for this tough-luck star seemingly doesn’t improve: Paul Crowther of the University of Sheffield, a member of the team who made the observations of 30 Dor #016, said the wayward star will continue to streak across space and will eventually end its life in a titanic supernova explosion, likely leaving behind a remnant black hole. There’s a new reality series in there somewhere!
The star on the run is found 375 light-years from its suspected home, a giant star cluster called R136 in 30 Doradus, also called the Tarantula Nebula, about roughly 170,000 light-years from Earth. R136 contains several stars topping 100 solar masses each. 30 Dor #016 is 90 times more massive than our Sun.
Astronomers say runaway stars can be made in a couple of ways: a star may encounter one or two heavier siblings in a massive, dense cluster and get booted out through a stellar game of pinball. Or, a star may get a ‘kick’ from a supernova explosion in a binary system, with the more massive star exploding first.
“It is generally accepted, however, that R136 is sufficiently young, 1 million to 2 million years old, that the cluster’s most massive stars have not yet exploded as supernovae,” says COS team member Danny Lennon of the Space Telescope Science Institute. “This implies that the star must have been ejected through dynamical interaction.” 30 Dor with 30 Dor #16 in the inset. Image credits: : NASA, ESA, J. Walsh (ST-ECF), and ESO
The renegade star may not be the only runaway in the region. Two other extremely hot, massive stars have been spotted beyond the edges of 30 Doradus. Astronomers suspect that these stars, too, may have been ejected from their home. They plan to analyze the stars in detail to determine whether 30 Doradus might be unleashing a barrage of massive stellar runaways into the surrounding neighborhood.
The observations came from a team-effort using Hubble’s newly installed Cosmic Origins Spectrograph (COS) to take an image of the region in 2009, an optical image of the star taken by the Wide Field Planetary Camera 2 in 1995, and another spectroscopic study from the European Southern Observatory’s Very Large Telescope (VLT) at the Paranal Observatory. It was first observed in 2006 when a team led by Ian Howarth of University College London spotted it with the Anglo-Australian Telescope at Siding Spring Observatory.
COS’s ultraviolet spectroscopic observations showed that the wayward star is unleashing a fury of charged particles in one of the most powerful stellar winds known, a clear sign that it is extremely massive, perhaps as much as 90 times heavier than the Sun. The star, therefore, also must be very young, about 1 million to 2 million years old, because extremely massive stars live only a few million years.
The VLT observations revealed that the star’s velocity is constant and not a result of orbital motion in a binary system. Its velocity corresponds to an unusual motion relative to the star’s surroundings, evidence that it is a runaway star.
The study also confirmed that the light from the runaway is from a single massive star rather than the combined light of two lower-mass stars. In addition, the observation established that the star is about 10 times hotter than the Sun, a temperature that is consistent with a high-mass object.
“These results are of great interest because such dynamical processes in very dense, massive clusters have been predicted theoretically for some time, but this is the first direct observation of the process in such a region,” says Nolan Walborn of the Space Telescope Science Institute in Baltimore and a member of the COS team that observed the misfit star. “Less massive runaway stars from the much smaller Orion Nebula Cluster were first found over half a century ago, but this is the first potential confirmation of more recent predictions applying to the most massive young clusters.”
The research team, led by Chris Evans of the Royal Observatory Edinburgh, published the study’s results May 5 in the online edition of The Astrophysical Journal Letters.
A Hubble Space Telescope image of the galaxy studied by Marianne Heida. The white circle marks the centre of the galaxy and the red circle marks the position of the suspected offset black hole. Image: STScI / NASA
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Supermassive black holes are thought to lie at the center of most large galaxies. But off in a distant remote galaxy, astronomers have possibly found a giant black hole that appears to be in the process of being expelled from the galaxy at high speed. This newly-discovered object was found by Marianne Heida, a student at Utrecht University in the Netherlands, and confirmed by an international team of astronomers who say the black hole was likely kicked out of its galaxy as a result of the merger of two smaller black holes.
Heida discovered the bizarre object, called CXO J122518.6+144545 during her final undergraduate project while doing research at the SRON Netherlands Institute for Space Research. To make the discovery she had to compare hundreds of thousands of X-ray sources, picked up by chance, with the positions of millions of galaxies. X-rays are also able to penetrate the dust and gas that surround black holes, with the bright source appearing as a starlike point. This object was very bright; however, it wasn’t at the center of a galaxy.
Super-massive black holes easily weigh more than 1 billion times the mass of the sun. So how could such a heavy object be hurled away from the galaxy at such high speeds? Astronomers say the expulsion can take place under special conditions when two black holes merge. The merger process creates a new black hole, and supercomputer models suggest that the larger black hole that results is shot out away at high speed, depending on the direction and speed in which the two black holes rotate before their collision.
And, the team of astronomers say, there could be more of these “recoiling” black holes out there. “We have found even more of this strange class of X-ray sources,” said Heida. “However, for these objects we first of all need accurate measurements from NASA’s Chandra satellite to pinpoint them more precisely.”
If this object is not a recoiling black hole, other possibilities are that it could possibly be either a very blue type IIn supernova or a ULX (ultra-luminous X-ray source) with a very bright optical counterpart.
Finding more of these expelled black holes will provide a better understanding of the characteristics of black holes before they merge. In the future, astronomers hope to even observe this process with the planned LISA satellite, which will be able to measure the gravity waves that the two merging black holes emit. Further research will provide more insight into how supermassive black holes are created.
The black spot in the green-tinged cloud near the top of the image is a hole blown through NGC 1999 by the jets and winds of gas from the young stellar objects in this region of space. Credits: ESA/HOPS Consortium
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There is a black patch of space in NGC 1999, and for years astronomers have thought it was just a dense cloud of gas and dust, blocking light from passing through. But the Herschel infrared space telescope – which has the ability to peer into these dense clouds — has made an unexpected discovery. This black patch is actually a hole that has been blown in the side of the nebula by the jets and winds of gas from the young stellar objects in this region of space. “No-one has ever seen a hole like this,” said Tom Megeath, of the University of Toledo in the USA. “It’s as surprising as knowing you have worms tunneling under your lawn, but finding one morning that they have created a huge, yawning pit.”
Any previous descriptions of NCG 1999 said that the ominous dark cloud in the center was actually a condensation of cold molecular gas and dust so thick and dense that it blocks light. And astronomers had no reason to believe otherwise, until Herschel’s powerful infrared eyes took a look from space. A Hubble image of NCG 1999 showing the dark patch. Credit: Hubble Heritage Team (STScI) and NASA
When Herschel looked in the direction of this nebula to study nearby young stars, the cloud continued to look black. But, that should not be the case. Herschel’s infrared eyes are designed to see into such clouds. Either the cloud was immensely dense or something was wrong.
Investigating further using ground-based telescopes, astronomers found the same story however they looked: this patch looks black not because it is a dense pocket of gas but because it is truly empty. Something has blown a hole right through the cloud.
Stars are born in dense clouds of dust and gas. Although jets and winds of gas have been seen coming from young stars in the past, it has always been a mystery exactly how a star uses these to blow away its surroundings and emerge from its birth cloud. With Herschel, this may be the first time we can see this process.
The astronomers think that the hole must have been opened when the narrow jets of gas from some of the young stars in the region punctured the sheet of dust and gas that forms NGC 1999. The powerful radiation from a nearby mature star may also have helped to clear the hole. Whatever the precise chain of events, it could be an important glimpse into the way newborn stars disperse their birth clouds.
How did you do in last week’s Universe Puzzle? Did you figure out an answer, but didn’t write up your reasons why it was the best?
Do you enjoy these puzzles? What do you particularly like? Dislike? Would like to see changed? Would like to see more of? Let me know please!
Once again, this week’s puzzle requires you to cudgel your brains a bit and do some lateral thinking (five minutes spent googling likely won’t be enough). But, as with all Universe Puzzles, this is a puzzle on a “Universal” topic – astronomy and astronomers; space, satellites, missions, and astronauts; planets, moons, telescopes, and so on.
Say you’re at a friend’s place for a party. They’re playing some 60’s rock music, and a catchy song comes round. You wonder who the band is, and someone says “it’s the most famous 60’s band that you’ve never heard of!” (perhaps it’s Herman’s Hermits).
Well, this week’s Universe Puzzle is:
Who is the most famous astronaut you’ve never heard of?
And for ‘astronaut’ let’s include cosmonauts, taikonauts, and so on.
Be sure to explain your pick.
Update: answer posted below.
There certainly is not just one best answer!
You, dear commenters, are the judges: which of the answers below do you think is the best?
Universe Puzzle will be taking a bit of break, so there won’t be one next week. However, I really would appreciate your feedback: which of the 13 puzzles so far did you most like? which did you least like? what sort of puzzles would you like to see in future?
The STS-132 crew arrived Monday evening at Kennedy Space Center. Image credit: Alan Walters (awaltersphoto.com) for Universe Today.
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As the space shuttle crew arrived at Kennedy Space Center for Thursday’s scheduled launch of the STS-132 mission, already on board space shuttle Atlantis is a piece of physicist Sir Isaac Newton’s apple tree. A 4-inch-long wood sample from the original tree that supposedly inspired Newton’s theory of gravity, along with a picture of Newton, will be taken into orbit by British-born astronaut Piers Sellers, a member of the crew for this next mission to the International Space Station. The wood is part of the collection of the Royal Society archives in London, and will be returned there following the flight. “We’re delighted to take this piece of Sir Isaac Newton’s apple tree to orbit,” said Sellers in an article from AFP. “While it’s up there, it will be experiencing no gravity, so if it had an apple on it, the apple wouldn’t fall.”
*Of course, that is not quite correct.
The piece of Newton’s tree is will still be experiencing gravity, and in fact, will be falling the entire time it is in orbit. It will be in free fall along with the shuttle and space station as it orbits the Earth. A free-falling object falls under the sole influence of gravity, and in the case of the shuttle (or any object in orbit), its orbital motion keeps it moving fast enough that it doesn’t fall back to Earth — unless its acceleration changes.
SXDF-XCLJ0218-0510. Max-Planck-Institut für extraterrestrische Physik
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Like a location from Star Wars, this galaxy cluster is far, far away and with origins a long, long time ago. With the ungainly name of SXDF-XCLJ0218-0510, this cluster is actually the most distant cluster of galaxies ever seen. It is a whopping 9.6 billion light years away, and X-ray and infrared observations show that the cluster hosts predominantly old, massive galaxies. This means the galaxies formed when the universe was still very young, so finding this cluster and being able to see it is providing new information not only about early galaxy evolution but also about history of the universe as a whole.
An international team of astronomers from the Max Planck Institute for Extraterrestrial Physics, the University of Tokyo and the Kyoto University discovered this cluster using the Subaru telescope along with the XMM-Newton space observatory to look in different wavelengths.
Using the Multi-Object Infrared Camera and Spectrometer (MOIRCS) on the Subaru telescope, the team was able to look in near-infrared wavelengths, where the galaxies are most luminous.
“The MOIRCS instrument has an extremely powerful capability of measuring distances to galaxies. This is what made our challenging observation possible,” said Masayuki Tanaka from the University of Tokyo. “Although we confirmed only several massive galaxies at that distance, there is convincing evidence that the cluster is a real, gravitationally bound cluster.”
Like a contour map, the arrows in the image above indicate galaxies that are likely located at the same distance, clustered around the center of the image. The contours indicate the X-ray emission of the cluster. Galaxies with confirmed distance measurements of 9.6 billion light years are circled. The combination of the X-ray detection and the collection of massive galaxies unequivocally proves a real, gravitationally bound cluster.
That the individual galaxies are indeed held together by gravity is confirmed by observations in a very different wavelength regime: The matter between the galaxies in clusters is heated to extreme temperatures and emits light at much shorter wavelengths than visible to the human eye. The team therefore used the XMM-Newton space observatory to look for this radiation in X-rays.
“Despite the difficulties in collecting X-ray photons with a small effective telescope size similar to the size of a backyard telescope, we detected a clear signature of hot gas in the cluster,” said Alexis Finoguenov from the Max Planck Institute for Extraterrestrial Physics.
The combination of these different observations in what are invisible wavelengths to the human eye led to the pioneering discovery of the galaxy cluster at a distance of 9.6 billion light years – some 400 million light years further into the past than the previously most distant cluster known.
An analysis of the data collected about the individual galaxies shows that the cluster contains already an abundance of evolved, massive galaxies that formed some two billion years earlier. As the dynamical processes for galaxy aging are slow, presence of these galaxies requires the cluster assembly through merger of massive galaxy groups, each nourishing its dominant galaxy. The cluster is therefore an ideal laboratory for studying the evolution of galaxies, when the universe was only about a third of its present age.
As distant galaxy clusters are also important tracers of the large scale structure and primordial density fluctuations in the universe, similar observations in the future will lead to important information for cosmologists. The results obtained so far demonstrate that current near infrared facilities are capable of providing a detailed analysis of distant galaxy populations and that the combination with X-ray data is a powerful new tool. The team therefore is continuing the search for more distant clusters.
Big Impact-Triggered Dust Avalanche seen by the HIRSE camera on the Mars Reconnaissance Orbiter. (ESP_017229_2110) Credit: NASA/JPL/University of Arizona
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The HiRISE team from the Mars Reconnaissance Orbiter has captured a few avalanches on Mars, some actually while in progress. But this latest landslide is a little different. Above is a dust avalanche that created a streak on the slopes of Olympus Mons, the solar system’s largest volcano. While scientists believe some of the previous avalanches seen on Mars occur due to the expansion and contraction of ice from seasonal temperature differences, this one was caused by an impact event. This HiRISE image was taken on March 31, 2010 and reveals a small, pristine impact crater (blue arrow). “It shows a fuzzy source area, which resembles the airblast patterns seen at many other recent impact sites,” said Alfred McEwen, Principal Investigator for HiRISE. “The crater is only about 4.5 meters across, meaning the bolide was only about a half a meter wide, so it didn’t take much to trigger this landslide.”
CTX images from Nov. 18, 2007 and Feb. 14, 2010. Credit: NASA/JPL/University of Arizona
MRO’s Context Camera (CTX) took an image of this area on Nov. 18, 2007 (left) and the adjacent image on Feb. 14, 2010, which shows a large new avalanche. HiRISE then took the follow-up image in March. McEwen said slope streaks , or dust avalanches are common on Mars, but this one is unusually wide and began from an unusual extended or “fuzzy” source area. This made HiRISE team conclude that an impact event occurred sometime between the dates of the CTX images and triggered the large dust avalanche.
“Sometimes, these dust avalanches are easily triggered,” McEwen told Universe Today. “We’ve seen them caused just by dust devils. The dark area was created by an atmospheric blast associated with the impact event, with the bolide coming in at about 10 km per second that distributes the dust. You can see that the upper most fresh dust on the surface is bright, so this landslide disturbed either bare substrate or compacted, older dust.
Color image of the impact-triggered dust avalanche. Credit: NASA/JPL/University of Arizona
Planetary scientists say that landslides or avalanches on Mars can also be caused by small Mars-quakes or the sublimation of carbon dioxide frost which dislodges rocks.
Sources: HiRISE, phone conversation with Alfred McEwen.
