Monthly Archives: June 2011

As arctic ice shrinks, so does a denier claim | Bad Astronomy

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It’s been known for some time that the ice sheet in the arctic is thinning. And now, a new study (PDF) by the Arctic Monitoring and Assessment Program lays this out in grim detail.

The report lists 15 key findings about the changes at the Earth’s northern regions. Fifteen. Here are four that alarmed me particularly:


1) The past six years (2005–2010) have been the warmest period ever recorded in the Arctic. Higher surface air temperatures are driving changes in the cryosphere.

3) The extent and duration of snow cover and sea ice have decreased across the Arctic. Temperatures in the permafrost have risen by up to 2 °C. The southern limit of permafrost has moved northward in Russia and Canada.

7) The Arctic Ocean is projected to become nearly ice-free in summer within this century, likely within the next thirty to forty years.

12) Loss of ice and snow in the Arctic enhances climate warming by increasing absorption of the sun’s energy at the surface of the planet. It could also dramatically increase emissions of carbon dioxide and methane and change large-scale ocean currents. The combined outcome of ...


On the Subject of Fox News, Jon Stewart Shouldn’t Have Backed Down | The Intersection

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Here’s a great segment from Jon Stewart last night–although it has one flaw. But watch first:

The problem is, Stewart wasn’t actually wrong, not even in the teeny way that he confessed to. Politifact cited the wrong studies to refute him, while ignoring numerous studies that I have found, all of which support Stewart. For a full explanation, see my latest DeSmogBlog item. Brief excerpt:

It is of course around contested political facts, and contested scientific facts, where we find active, politically impelled, and emotionally laden misinformation campaigns—and it is in the latter realm that Fox News viewers are clearly more misinformed. Once again, I’ve cited 5 studies to this effect—concerning the Iraq war, the 2010 election, global warming, health care reform, and the Ground Zero Mosque. By contrast, Politifact only cites two of these studies, and attempts to critique one of them (the 2010 election study)—misguidedly to my mind, but who really even cares. It is obvious where the weight of the evidence lies at this point, unless further, relevant studies are brought to bear.

As a result of all of this, Politifact should either produce relevant research to rebut Stewart, or run a far more forthcoming retraction than has been issued so far. Note, however, that the issue grew a tad more complicated last night when Stewart did an excellent segment on all of this, where he both dramatized how much Fox misinformed viewers and yet also kind of conceded Politifact’s point, when he didn’t actually have to. He wasn’t wrong. They were wrong.

When the fact checkers fail—and in this case, they not only failed, they generated a falsehood of their own–they have a special responsibility to self-correct.

Again, full post here.


Don’t Miss Out on Creating the Future

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Time is running out to enter the 2011 "Create the Future" Design Contest. Entries for the ninth annual contest are due by June 30th. Click here to submit your design idea.

Sponsored by COMSOL, Creo - a PTC product, and Tech Briefs Media Group, the contest recognizes outstanding innovations in product design, awarding a Grand Prize of $20,000 USD.

New this year is an Electronics Design category sponsored by Digi-Key Corp. Other categories are Consumer Products, Machinery & Equipment, Medical, Safety and Security, Sustainable Technologies, and Transportation. Entries can be submitted by individuals and/or teams in up to seven categories.

The top entry in each category will receive a workstation computer from Hewlett-Packard. The top ten most popular entries, as voted on by site registrants, will get a 3D mouse from 3Dconnexion. All qualified entrants will be included in a drawing for NASA Tech Briefs T-shirts, and the winning entries will be featured in a special supplement to NASA Tech Briefs magazine.

If you haven’t submitted your design, you have until June 30th to visit http://www.createthefuture2011.com and enter your great idea.

Is This The Next Lamborghini?

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Sure, design-school renderings are a dime a dozen, and most of them never end up seeing the light of day in production or even as life-sized concepts. But this one, the Ankonian concept by Slavche Tanevski of the Munich University of Applied Sciences, very much captures and extends the desig

Strange New Glass Proves Twice as Durable as Steel

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From Discover Technology:

Engineers have long sought a material with the strength of glass and the toughness of metal. But the two properties are virtually mutually exclusive. Strong, rigid materials tend to be brittle (think glass), while tough ones that resist shattering are often mall

The Burning Question

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Some say packaging professionals should remain neutral in the "incineration vs. recycling" debate. Others say weigh in. The politically correct or easiest cause to support has always been recycling. But both recycling and incineration keep packaging out of landfills, presumably the least favorable o

Beware of Internal Threats

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In a dangerous world, most companies are cognizant that threats may come from outside their walls. However, some threats might come from within such as when a worker tries to trigger an explosion or a trusted supplier turns out not to be so trustworthy. How do you "lock out" internal threats?

The p

Do Instrument Interfaces Need Updating?

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Will touch screens and gestures replace the buttons, knobs, and non-touch-sensitive displays we currently find on equipment? What's your take? Are smart phones and tablets pointing the way to promising new ways of controlling instruments and other gear?

The preceding article is a "sneak peek" from

NASA Scientists Theorize Titan Shaped By Weather, Not Ice Volcanoes

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Have the surface and belly of Saturn's smog-shrouded moon, Titan, recently simmered like a chilly, bubbling cauldron with ice volcanoes, or has this distant moon gone dead? In a newly published analysis, a pair of NASA scientists analyzing data collected by the Cassini spacecraft suggest Titan may be much less geologically active than some scientists think.

In the paper, published in the April 2011 edition of the journal Icarus, scientists conclude Titan's interior may be cool and dormant and incapable of causing active ice volcanoes.

"It would be fantastic to find strong evidence that clearly shows Titan has an internal heat source that causes ice volcanoes and lava flows to form," said Jeff Moore, lead author of the paper and a planetary scientist at NASA's Ames Research Center, Moffett Field, Calif. "But we find that the evidence presented to date is unconvincing, and recent studies of Titan’s interior conducted by geophysicists and gravity experts also weaken the possibility of volcanoes there."

Scientists agree that Titan shows evidence of having lakes of liquid methane and ethane, and valleys carved by these exotic liquids, as well as impact craters. However, a debate continues to brew about how to interpret the Cassini data about Titan. Some scientists theorize ice volcanoes exist and suggest energy from an internal heat source may have caused ice to rise and release methane vapors as it reached Titan’s surface.

But in the new paper, the authors conclude that the only features on Titan’s surface that have been unambiguously identified were created by external forces – such as objects hitting the surface and creating craters, wind and rain pummeling its surface, and the formation of rivers and lakes.

"Titan is a fascinating world," said Robert Pappalardo, a research scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif., and former Cassini project scientist. "Its uniqueness comes from its atmosphere and organic lakes, but in this study, we find no strong evidence for icy volcanism on Titan."

In December 2010, a group of Cassini scientists presented new topographic data on an area of Titan called Sotra Facula, which they think makes the best case yet for a possible volcanic mountain that once erupted ice on Titan. Although Moore and Pappalardo do not explicitly consider this recent topographic analysis in their paper, they do not find the recent analysis of Sotra Facula to be convincing so far. It remains to be seen whether ongoing analyses of Sotra Facula can change minds.

Titan, Saturn's largest moon, is the only known moon to have a dense atmosphere, composed primarily of nitrogen, with two to three percent methane. One goal of the Cassini mission is to find an explanation for what, if anything, might be maintaining this atmosphere.

Titan's dense atmosphere makes its surface very difficult to study with visible-light cameras, but infrared instruments and radar signals can peer through the haze and provide information about both the composition and shape of the surface.

"Titan is most akin to Jupiter's moon Callisto, if Callisto had weather," Moore added. "Every feature we have seen on Titan can be explained by wind, rain, and meteorite impacts, rather than from internal heating."

Callisto is almost the exact same size as Titan. It has a cratered appearance and because of its cool interior, its surface features are not affected by internal forces. Moore and Pappalardo conclude that Titan also may have a cool interior, with only external processes like wind, rain and impacts shaping its surface."

The Cassini spacecraft, currently orbiting Saturn, continues to make fly-bys of Titan. Scientists will continue to explore Titan's mysteries, including investigations of the changes in the landscapes.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and several of its instruments were designed, developed and assembled at JPL.

For more information visit http://www.nasa.gov/topics/solarsystem/features/Titan_Ice_Volcanoes.html

Gardening in Space with HydroTropi

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Plants are fundamental to life on Earth, converting light and carbon dioxide into food and oxygen. Plant growth may be an important part of human survival in exploring space, as well. Gardening in space has been part of the International Space Station from the beginning -- whether peas grown in the Lada greenhouse or experiments in the Biomass Production System. The space station offers unique opportunities to study plant growth and gravity, something that cannot be done on Earth.

The latest experiment that has astronauts putting their green thumbs to the test is Hydrotropism and Auxin-Inducible Gene expression in Roots Grown Under Microgravity Conditions, known as HydroTropi. Operations were conducted October 18-21, 2010. HydroTropi is a Japan Aerospace Exploration Agency (JAXA)-run study that looks at directional root growth. In microgravity, roots grow latterly or sideways, instead of up and down like they do under Earth’s gravitational forces.

Using cucumber plants (scientific name Cucumis sativus), investigators look to determine whether hydrotropic -- plant root orientation due to water—response can control the direction of root growth in microgravity. To perform the HydroTropi experiment, astronauts transport the cucumber seeds from Earth to the space station and then coax them into growth. The seeds, which reside in Hydrotropism chambers, undergo 18 hours of incubation in a Cell Biology Experiment Facility or CBEF. Then the crewmembers activate the seeds with water or a saturated salt solution, followed by a second application of water 4 to 5 hours later. The crew harvests the cucumber seedlings and preserves them using fixation tubes called Kenney Space Center Fixation Tubes or KFTs, which then store in one of the station MELFI freezers to await return to Earth.

The results from HydroTropi, which returns to Earth on STS-133, will help investigators to better understand how plants grow and develop at a molecular level. The experiment will demonstrate a plant’s ability to change growth direction in response to gravity (gravitropism) vs. directional growth in response to water (hydrotropism). By looking at the reaction of the plants to the stimuli and the resulting response of differential auxin -- the compound regulating the growth of plants -- investigators will learn about plants inducible gene expression. In space, investigators hope HydroTropi will show them how to control directional root growth by using the hydrotropism stimulus; this knowledge may also lead to significant advancements in agriculture production on Earth.

For more information visit http://www.nasa.gov/mission_pages/station/research/news/hydrotropi.html

MESSENGER Provides New Data about Mercury

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After nearly three months in orbit about Mercury, MESSENGER's payload is providing a wealth of new information about the planet closest to the Sun, as well as a few surprises.

The spacecraft entered orbit around Mercury on March 18, 2011 UTC, becoming the first spacecraft ever to do so. Tens of thousands of images of major features on the planet — previously seen only at comparatively low resolution — are now available in sharp focus. Measurements of the chemical composition of Mercury's surface are providing important clues to the origin of the planet and its geological history. Maps of the planet's topography and magnetic field are revealing new clues to Mercury's interior dynamical processes. And scientists now know that bursts of energetic particles in Mercury's magnetosphere are a continuing product of the interaction of Mercury's magnetic field with the solar wind.

This week, MESSENGER completed is first perihelion passage from orbit, its first superior solar conjunction from orbit, and its first orbit-correction maneuver. "Those milestones provide important context to the continuing feast of new observations that MESSENGER has been sending home on nearly a daily basis,” offers MESSENGER Principal investigator Sean Solomon of the Carnegie Institution of Washington.

A Surface Revealed in Unprecedented Detail

Among the fascinating features seen in MESSENGER flyby images of Mercury were bright, patchy deposits on some crater floors. Without high-resolution images to obtain a closer look, these features remained a curiosity. New targeted Mercury Dual Imaging System images at up to 10 meters per pixel reveal these patchy deposits to be clusters of rimless, irregular pits varying in size from hundreds of meters to several kilometers. These pits are often surrounded by diffuse halos of higher-reflectance material, and they are found associated with central peaks, peak rings, and rims of craters.

"The etched appearance of these landforms is unlike anything we've seen before on Mercury or the Moon,” says Brett Denevi, a staff scientist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., and a member of the MESSENGER imaging team. "We are still debating their origin, but they appear to have a relatively young age and may suggest a more abundant than expected volatile component in Mercury's crust.”

Mercury's Surface Composition

The X-ray Spectrometer (XRS) — one of two instruments on MESSENGER designed to measure the abundances of many key elements on Mercury — has made several important discoveries since the orbital mission began. The magnesium/silicon, aluminum/silicon, and calcium/silicon ratios averaged over large areas of the planet's surface show that, unlike the surface of the Moon, Mercury's surface is not dominated by feldspar-rich rocks.

XRS observations have also revealed substantial amounts of sulfur at Mercury's surface, lending support to prior suggestions from ground-based telescopic spectral observations that sulfide minerals are present. This discovery suggests that the original building blocks from which Mercury was assembled may have been less oxidized than those that formed the other terrestrial planets, and it has potentially important implications for understanding the nature of volcanism on Mercury.

Mapping of Mercury's Topography and Magnetic Field

MESSENGER's Mercury Laser Altimeter has been systematically mapping the topography of Mercury's northern hemisphere. After more than two million laser-ranging observations, the planet's large-scale shape and profiles of geological features are both being revealed in high detail. The north polar region of Mercury, for instance, is a broad area of low elevations. The overall range in topographic heights seen to date exceeds 9 kilometers.

Two decades ago, Earth-based radar images showed that around both Mercury's north and south poles are deposits characterized by high radar backscatter. These polar deposits are thought to consist of water ice and perhaps other ices preserved on the cold, permanently shadowed floors of high-latitude impact craters. MESSENGER's altimeter is testing this idea by measuring the floor depths of craters near Mercury's north pole. To date, the depths of craters hosting polar deposits are consistent with the idea that those deposits occupy areas in permanent shadow.

Energetic Particle Events at Mercury

One of the major discoveries made by Mariner 10 during the first of its three flybys of Mercury in 1974 were bursts of energetic particles in Mercury's Earth-like magnetosphere. Four bursts of particles were observed on that flyby, so it was puzzling that no such strong events were detected by MESSENGER during any of its three flybys of the planet in 2008 and 2009. With MESSENGER now in near-polar orbit about Mercury, energetic events are being seen almost like clockwork.

"We are assembling a global overview of the nature and workings of Mercury for the first time,” adds Solomon, "and many of our earlier ideas are being cast aside as new observations lead to new insights. Our primary mission has another three Mercury years to run, and we can expect more surprises as our solar system's innermost planet reveals its long-held secrets."

For more information visit http://www.nasa.gov/mission_pages/messenger/media/NewsConference20110616.html

Firestorm of Star Birth in the Active Galaxy Centaurus A

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Resembling looming rain clouds on a stormy day, dark lanes of dust crisscross the giant elliptical galaxy Centaurus A.

Hubble's panchromatic vision, stretching from ultraviolet through near-infrared wavelengths, reveals the vibrant glow of young, blue star clusters and a glimpse into regions normally obscured by the dust.

The warped shape of Centaurus A's disk of gas and dust is evidence for a past collision and merger with another galaxy. The resulting shockwaves cause hydrogen gas clouds to compress, triggering a firestorm of new star formation. These are visible in the red patches in this Hubble close-up.

At a distance of just over 11 million light-years, Centaurus A contains the closest active galactic nucleus to Earth. The center is home for a supermassive black hole that ejects jets of high-speed gas into space, but neither the supermassive or the jets are visible in this image.

This image was taken in July 2010 with Hubble's Wide Field Camera 3.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI) conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington, D.C.

For more information visit http://www.nasa.gov/mission_pages/hubble/science/galaxy-firestorm.html

NASA’s Chandra Finds Massive Black Holes Common in Early Universe

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Using the deepest X-ray image ever taken, astronomers found the first direct evidence that massive black holes were common in the early universe. This discovery from NASA's Chandra X-ray Observatory shows that very young black holes grew more aggressively than previously thought, in tandem with the growth of their host galaxies.

By pointing Chandra at a patch of sky for more than six weeks, astronomers obtained what is known as the Chandra Deep Field South (CDFS). When combined with very deep optical and infrared images from NASA's Hubble Space Telescope, the new Chandra data allowed astronomers to search for black holes in 200 distant galaxies, from when the universe was between about 800 million to 950 million years old.

"Until now, we had no idea what the black holes in these early galaxies were doing, or if they even existed,” said Ezequiel Treister of the University of Hawaii, lead author of the study appearing in the June 16 issue of the journal Nature. “Now we know they are there, and they are growing like gangbusters."

The super-sized growth means that the black holes in the CDFS are less extreme versions of quasars -- very luminous, rare objects powered by material falling onto supermassive black holes. However, the sources in the CDFS are about a hundred times fainter and the black holes are about a thousand times less massive than the ones in quasars.

The observations found that between 30 and 100 percent of the distant galaxies contain growing supermassive black holes. Extrapolating these results from the small observed field to the full sky, there are at least 30 million supermassive black holes in the early universe. This is a factor of 10,000 larger than the estimated number of quasars in the early universe.

“It appears we've found a whole new population of baby black holes,” said co-author Kevin Schawinski of Yale University. “We think these babies will grow by a factor of about a hundred or a thousand, eventually becoming like the giant black holes we see today almost 13 billion years later.”

A population of young black holes in the early universe had been predicted, but not yet observed. Detailed calculations show that the total amount of black hole growth observed by this team is about a hundred times higher than recent estimates.

Because these black holes are nearly all enshrouded in thick clouds of gas and dust, optical telescopes frequently cannot detect them. However, the high energies of X-ray light can penetrate these veils, allowing the black holes inside to be studied.

Physicists studying black holes want to know more how the first supermassive black holes were formed and how they grow. Although evidence for parallel growth of black holes and galaxies has been established at closer distances, the new Chandra results show that this connection starts earlier than previously thought, perhaps right from the origin of both.

“Most astronomers think in the present-day universe, black holes and galaxies are somehow symbiotic in how they grow,” said Priya Natarajan, a co-author from Yale University. “We have shown that this codependent relationship has existed from very early times.”

It has been suggested that early black holes would play an important role in clearing away the cosmic "fog" of neutral, or uncharged, hydrogen that pervaded the early universe when temperatures cooled down after the Big Bang. However, the Chandra study shows that blankets of dust and gas stop ultraviolet radiation generated by the black holes from traveling outwards to perform this “reionization.” Therefore, stars and not growing black holes are likely to have cleared this fog at cosmic dawn.

Chandra is capable of detecting extremely faint objects at vast distances, but these black holes are so obscured that relatively few photons can escape and hence they could not be individually detected. Instead, the team used a technique that relied on Chandra’s ability to accurately determine the direction from which the X-rays came to add up all the X-ray counts near the positions of distant galaxies and find a statistically significant signal.

NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for the agency's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass.

For more information visit http://www.nasa.gov/mission_pages/chandra/news/H-11-183.html

New Insights On How Solar Minimums Affect Earth

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Since 1611, humans have recorded the comings and goings of black spots on the sun. The number of these sunspots wax and wane over approximately an 11-year cycle -- more sunspots generally mean more activity and eruptions on the sun and vice versa. The number of sunspots can change from cycle to cycle and 2008 saw the longest and weakest solar minimum since scientists have been monitoring the sun with space-based instruments.

Observations have shown, however, that magnetic effects on Earth due to the sun, effects that cause the aurora to appear, did not go down in synch with the cycle of low magnetism on the sun. Now, a paper in Annales Geophysicae that appeared on May 16, 2011 reports that these effects on Earth did in fact reach a minimum -- indeed they attained their lowest levels of the century -- but some eight months later. The scientists believe that factors in the speed of the solar wind, and the strength and direction of the magnetic fields embedded within it, helped produce this anomalous low.

"Historically, the solar minimum is defined by sunspot number," says space weather scientist Bruce Tsurutani at NASA's Jet Propulsion Lab in Pasadena, Calif., who is first author on the paper. "Based on that, 2008 was identified as the period of solar minimum. But the geomagnetic effects on Earth reached their minimum quite some time later in 2009. So we decided to look at what caused the geomagnetic minimum."

Geomagnetic effects basically amount to any magnetic changes on Earth due to the sun, and they're measured by magnetometer readings on the surface of the Earth. Such effects are usually harmless, the only obvious sign of their presence being the appearance of auroras near the poles. However, in extreme cases, they can cause power grid failures on Earth or induce dangerous currents in long pipelines, so it is valuable to know how the geomagnetic effects vary with the sun.

Three things help determine how much energy from the sun is transferred to Earth's magnetosphere from the solar wind: the speed of the solar wind, the strength of the magnetic field outside Earth's bounds (known as the interplanetary magnetic field) and which direction it is pointing, since a large southward component is necessary to connect successfully to Earth's magnetosphere and transfer energy. The team -- which also included Walter Gonzalez and Ezequiel Echer of the Brazilian National Institute for Space Research in São José dos Campos, Brazil -- examined each component in turn.

First, the researchers noted that in 2008 and 2009, the interplanetary magnetic field was the lowest it had been in the history of the space age. This was an obvious contribution to the geomagnetic minimum. But since the geomagnetic effects didn't drop in 2008, it could not be the only factor.

To examine the speed of the solar wind, they turned to NASA's Advanced Composition Explorer (ACE), which is in interplanetary space outside the Earth’s magnetosphere, approximately 1 million miles toward the sun. The ACE data showed that the speed of the solar wind stayed high during the sunspot minimum. Only later did it begin a steady decline, correlating to the timing of the decline in geomagnetic effects.

The next step was to understand what caused this decrease. The team found a culprit in something called coronal holes. Coronal holes are darker, colder areas within the sun's outer atmosphere. Fast solar wind shoots out the center of coronal holes at speeds up to 500 miles per second, but wind flowing out of the sides slows down as it expands into space.

"Usually, at solar minimum, the coronal holes are at the sun's poles," says Giuliana de Toma, a solar scientist at the National Center for Atmospheric Research whose research on this topic helped provide insight for this paper. "Therefore, Earth receives wind from only the edges of these holes and it's not very fast. But in 2007 and 2008, the coronal holes were not confined to the poles as normal."

Those coronal holes lingered at low-latitudes to the end of 2008. Consequently, the center of the holes stayed firmly pointed towards wind at Earth begin to slow down. And, of course, the geomagnetic effects and sightings of the aurora along with it.

Coronal holes seem to be responsible for minimizing the southward direction of the interplanetary magnetic field as well. The solar wind's magnetic fields oscillate on the journey from the sun to Earth. These fluctuations are known as Alfvén waves. The wind coming out of the centers of the coronal holes have large fluctuations, meaning that the southward magnetic component – like that in all the directions -- is fairly large. The wind that comes from the edges, however, has smaller fluctuations, and comparably smaller southward components. So, once again, coronal holes at lower latitudes would have a better chance of connecting with Earth's magnetosphere and causing geomagnetic effects, while mid-latitude holes would be less effective.

Working together, these three factors -- low interplanetary magnetic field strength combined with slower solar wind speed and smaller magnetic fluctuations due to coronal hole placement -- create the perfect environment for a geomagnetic minimum.

Knowing what situations cause and suppress intense geomagnetic activity on Earth is a step toward better predicting when such events might happen. To do so well, Tsurutani points out, requires focusing on the tight connection between such effects and the complex physics of the sun. "It's important to understand all of these features better," he says. "To understand what causes low interplanetary magnetic fields and what causes coronal holes in general. This is all part of the solar cycle. And all part of what causes effects on Earth."

For more information visit http://www.nasa.gov/mission_pages/sunearth/news/solar-minima.html

NASA Chat: Giant Black Holes in the Early Universe

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Portrayed in movies and on television most often as gateways to another dimension or cosmic vacuum cleaners sucking up everything in sight, the misconceptions surrounding black holes are many and varied. In reality, black holes form when, at the end of their life cycle, heavy stars collapse into a supernova. These relatively puny black holes may provide a "seed" for the development of the giant black holes -- called supermassive -- found at the center of galaxies, which grow by absorbing gas, stars and other black holes.

On Wednesday, June 15, NASA will announce a new discovery about giant black holes in the early universe. This discovery was made using the Chandra X-ray Observatory. Chandra gives astronomers a powerful tool to investigate the universe, especially those hot spots where black holes, exploding stars and colliding galaxies are most likely to live. Since the Earth's atmosphere absorbs the vast majority of X-rays, they are not detectable from Earth-based telescopes, requiring a space-based telescope to make these observations. Chandra launched in 1999 aboard the Columbia during the STS-93 mission.

Astrophysicists Ezequiel Treister and Kevin Schawinski will be online at 3:00 p.m. EDT on June 15 to answer your questions about the announcement and about black holes in general. Joining the chat is easy. Simply visit this page on Wednesday, June 15, from 3 to 4 p.m. EDT. The chat window will open at the bottom of this page starting about 30 minutes before the chat. You can log in and be ready to ask questions at 3 p.m.

About the Experts

Ezequiel Treister is an astrophysicist for the Institute for Astronomy at the University of Hawaii at Manoa. He has a doctorate in astronomy from the Universidad de Chile, two masters degrees in astronomy from Yale University and a bachelors in physics, also from Universidad de Chile. His interests include active galactic nuclei -- the compact regions at the centers of galaxies with higher than normal luminosity over the electromagnetic spectrum. He studies these nuclei in relation to the cosmic X-ray and Infrared backgrounds of the universe.

Kevin Schawinski is currently an astrophysicist at Yale University in New Haven, Conn. He has a doctorate in astrophysics from the University of Oxford and a bachelors in physics and mathematics from Cornell University. His interests include how galaxies formed and how they co-evolved with the supermassive black holes that lurk at their centers.

For more information visit http://www.nasa.gov/connect/chat/chandra_chat.html