Posted on by Ian O'Neill

New Technique Allows Astronomers to Discover Exoplanets in Old Hubble Images

Using a new imaging technique on an 11 year old Hubble observation, an exoplanet has been discovered orbiting the young star HR 8799 (NASA/HST)

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The Hubble Space Telescope has recently provided us with some astonishing images of exoplanets orbiting distant stars. This is a departure from the indirect detection of exoplanets by measuring the “wobble” of stars (revealing the gravitational presence of a massive planetary body) or the transit of exoplanets through the line of sight of the parent star (causing its brightness to dim). Scientists have refined Hubble’s exoplanet hunting abilities to directly image these alien worlds in visible light. However, astronomers now have another trick to find these mysterious worlds. A new imaging technique is allowing us to see exoplanets already hiding in archival Hubble data…

It has been estimated that another 100 previously unknown exoplanets could be discovered in old Hubble data. The technique being tested by astronomers at the University of Toronto could be a very powerful new way to reveal the existence of a huge number of buried jewels buried by the glare of star light.

In November 2008, a spate of direct imagery of exoplanets showed the world how advanced our ground and space-based observatories were becoming. One such discovery was an observing campaign of the young star HR 8799 by the near-infrared adaptive optics observations of the Gemini and Keck telescopes. HR 8799 (140 light years away, approximately 50% more massive than our Sun) plays host to three massive gas giants (10, 10 and 7 times the size of Jupiter). Now that HR 8799 is known to have large exoplanets orbiting around it, the University of Toronto astronomers, headed by David Lafrenière, have re-examined images taken by Hubble of that same star in 1998, to see if there is any trace of these exoplanets in the old data. In 1998, HR 8799 appeared to be a lonely star, with no associated exoplanets.

Using a new technique to extract the weak exoplanet emission in the Hubble image, Lafrenière’s team have been able to cut down the glare of the parent star to reveal the presence of the outermost exoplanet of the trio known to be orbiting HR 8799 (pictured top). The other two exoplanets remain too close to the star to be resolved.

The University of Toronto result “definitely indicates that we should reanalyze all the existing Hubble images of young stars with the new approach — there’s probably 100 to 200 stars where planets could be seen,” comments planet-hunter Bruce Macintosh of the Lawrence Livermore National Laboratory in California. Many of these stars have already been studied by the powerful Keck observatory in Hawaii, so astronomers now have an exciting and powerful new analysis tool to hopefully reveal more overlooked exoplanets.

However, this most recent result was achieved by using a space-based observatory, as some of the near-infrared emission from the exoplanet will be absorbed by the Earth’s atmosphere.

The new exoplanet discovery potential has excited many astronomers, and it has highlighted the importance of maintaining a good archive of astronomical observations. “The first thing it tells you is how valuable maintaining long-term archives can be. Here is a major discovery that’s been lurking in the data for about 10 years!” said Matt Mountain, director of the Space Telescope Science Institute in Baltimore. “The second thing its tells you is having a well calibrated archive is necessary but not sufficient to make breakthroughs — it also takes a very innovative group of people to develop very smart extraction routines that can get rid of all the artifacts to reveal the planet hidden under all that telescope and detector structure.”

Hopefully we’ll be seeing even more exoplanet discoveries over the coming months, not just from new observing campaigns, but possibly from old observations using archived observatory data. Exciting times!

Source: Science News

Posted on by Ian O'Neill

Could a Second Ares I-X Test Flight Close the 5-Year Gap?

Artist impression of the Ares I-X at the launchpad, plus labelled sections of the rocket (NASA)

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Approximately $400 million extra has become available for NASA manned space flight and managers are currently discussing the possibility of using it toward a second test flight of the Ares I-X. The first test flight of the next generation launch vehicle is planned for a summer 2009 launch, and with this extra funding comes the possibility of a second test flight dubbed “Ares I-X prime”. In a renewed vigour for getting the US back to the Moon by 2020, and the looming “5-year gap”, it appears the extra funding may allow NASA to hasten the development of the Constellation Program…

So it turns out the economic stimulus package will affect the development of NASA’s Constellation Program after all, possibly speeding it up. Of growing concern is the fact that it is looking very likely (according to the White House budget blueprint) that the shuttle will be retired as planned in 2010, leaving five long years until the planned 2015 completion of the Constellation Program. This 5-year gap has spawned all kinds of political problems (i.e. depending on the Russian space agency to get US astronauts to the International Space Station), but it has also stimulated investment in private space launch companies.

Although details are still being worked out on how the extra money will be distributed, it is hoped that the $1 billion allocated to NASA from the stimulus package may “save or preserve 7,000 jobs”. The money invested in manned spaceflight could also speed up technological advancement, possibly speeding Constellation progress. Managers hope an extra test-flight of the Ares I-X could also be used to hasten development of prototype flight systems. Doug Cooke, associate administrator for exploration systems, confirmed that to use this extra funding for a second test flight “certainly is within the realm of possibility.”

By laying on a second test flight after the Ares I-X scheduled for this summer, Ares I-X prime could substantially accelerate progress, possibly reducing the 5-year gap by as much as a year. The second flight of the Ares I-X would test the five-segment version of the four-segment solid fuel shuttle booster that will act as the first stage of the Ares I. The solid fuel launch abort system would also be tested at high altitude.

Source: Aviation Week

Posted on by Ian O'Neill

Powerful Fusion Laser to Recreate Conditions Inside Exoplanets

A powerful laser could create the conditions inside a giant exoplanet (Sunbeamtech)

[/caption]We’ve all heard that the Large Hadron Collider (LHC) will collide particles together at previously unimaginable energies. In doing so, the LHC will recreate the conditions immediately after the Big Bang, thereby allowing us to catch a glimpse of what particles the Universe would have been filled with at this time. In a way, the LHC will be a particle time machine, allowing us to see the high energy conditions last seen immediately after the Big Bang, 13.7 billion years ago.

So, if we wanted to understand the conditions inside a giant exoplanet, how could we do it? We can’t directly measure it ourselves, we have to create a laboratory experiment that could recreate the conditions in the core of one of these huge exoplanet gas giants. Much like the LHC will recreate the conditions of the Big Bang, a powerful laser intended to kick-start fusion reactions will be used in an effort to help scientists have a very brief look into the cores of these distant worlds…

The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory in California is ready for action. The facility will perform fusion experiments, hopefully making a self-sustaining nuclear fusion reaction a reality using an incredibly powerful laser (firing at a hydrogen isotope fuel). Apart from the possibility of finding a way to kick-start a viable fusion energy source (other laboratories have tried, but only sustained fusion for an instant before fizzing out), the results from the laser tests will aid the management of the US nuclear weapon stockpile (since there have been no nuclear warhead tests in 15 years, data from the experiments may help the military deduce whether or not their bombs still work).

Fusion energy and nuclear bombs to one side, there is another use for the laser. It could be used to recreate the crushing pressures inside a massive exoplanet so we can glean a better understanding of what happens to matter at these crushing depths.

The NIF laser can deliver 500 trillion watts in a 20-nanosecond burst, which may not sound very long, but the energy delivered is immense. Raymond Jeanloz, an astronomer at the University of California, Berkeley, will have the exciting task of using the laser, aiming it at a small iron sample (800 micrometres in diameter), allowing him to generate a moment where pressures exceed a billion times atmospheric pressure. That’s 1000 times the pressure of the centre of the Earth.

On firing the laser, the heat will vaporize the iron, blasting a jet of gas so powerful, it will send a shock wave through the metal. The resulting compression is what will be observed and measured, revealing how the metal’s crystalline structure and melting point change at these pressures. The results from these tests will hopefully shed some light on the formation of the hundreds of massive exoplanets discovered in the last two decades.

“The chemistry of these planets is completely unexplored,” says Jeanloz. “It’s never been accessible in the laboratory before.”

Now that is one impressive laboratory experiment…

Source: New Scientist

Posted on by Nancy Atkinson

Ancient Pulsar Still Pulsing

Artist concept of ancient pulsar J0108. Image credit: X-ray: NASA/CXC/Penn State/G.Pavlov et al. Optical: ESO/VLT/UCL/R.Mignani et al. Illustration: CXC/M. Weiss

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It may be old, but it ain’t dead. The Chandra X-Ray Observatory has found the oldest isolated pulsar ever detected. While this pulsar is ancient, this exotic object is still kicking and is surprisingly active. According to radio observations, the pulsar, PSR J0108-1431 (J0108 for short) is about 200 million years old. Among isolated pulsars — ones that have not been spun-up in a binary system — it is over 10 times older than the previous record holder. A team of astronomers led by George Pavlov of Penn State University observed J0108 in X-rays with Chandra, and found that it glows much brighter in X-rays than was expected for a pulsar of such advanced years.

At a distance of 770 light years, it is also one of the nearest pulsars we know of.

Pulsars are created when stars that are much more massive than the Sun collapse in supernova explosions, leaving behind a small, incredibly weighty core, known as a neutron star. At birth, these neutron stars, which contain the densest material known in the Universe, are spinning rapidly, up to a hundred revolutions per second. As the rotating beams of their radiation are seen as pulses by distant observers, similar to a lighthouse beam, astronomers call them “pulsars”.

Astronomers observe a gradual slowing of the rotation of the pulsars as they radiate energy away. Radio observations of J0108 show it to be one of the oldest and faintest pulsars known, spinning only slightly faster than one revolution per second.

J0108 in a combination of optical and X-ray. Image credit: X-ray: NASA/CXC/Penn State/G.Pavlov et al. Optical: ESO/VLT/UCL/R.Mignani et al.
J0108 in a combination of optical and X-ray. Image credit: X-ray: NASA/CXC/Penn State/G.Pavlov et al. Optical: ESO/VLT/UCL/R.Mignani et al.

Some of the energy that J0108 is losing as it spins more slowly is converted into X-ray radiation. The efficiency of this process for J0108 is found to be higher than for any other known pulsar.

“This pulsar is pumping out high-energy radiation much more efficiently than its younger cousins,” said Pavlov. “So, although it’s clearly fading as it ages, it is still more than holding its own with the younger generations.”

It’s likely that two forms of X-ray emission are produced in J0108: emission from particles spiraling around magnetic fields, and emission from heated areas around the neutron star’s magnetic poles. Measuring the temperature and size of these heated regions can provide valuable insight into the extraordinary properties of the neutron star surface and the process by which charged particles are accelerated by the pulsar.

The younger, bright pulsars commonly detected by radio and X-ray telescopes are not representative of the full population of objects, so observing objects like J0108 helps astronomers see a more complete range of behavior. At its advanced age, J0108 is close to the so- called “pulsar death line,” where its pulsed radiation is expected to switch off and it will become much harder, if not impossible, to observe.

“We can now explore the properties of this pulsar in a regime where no other pulsar has been detected outside the radio range,” said co- author Oleg Kargaltsev of the University of Florida. “To understand the properties of ‘dying pulsars,’ it is important to study their radiation in X-rays. Our finding that a very old pulsar can be such an efficient X-ray emitter gives us hope to discover new nearby pulsars of this class via their X-ray emission.”

The Chandra observations were reported by Pavlov and colleagues in the January 20, 2009, issue of The Astrophysical Journal. However, the extreme nature of J0108 was not fully apparent until a new distance to it was reported on February 6 in the PhD thesis of Adam Deller from Swinburne University in Australia. The new distance is both larger and more accurate than the distance used in the Chandra paper, showing that J0108 was brighter in X-rays than previously thought.

“Suddenly this pulsar became the record holder for its ability to make X-rays,” said Pavlov, “and our result became even more interesting without us doing much extra work.” The position of the pulsar seen by Chandra in X-rays in early 2007 is slightly different from the radio position observed in early 2001. This implies that the pulsar is moving at a velocity of about 440,000 miles per hour, close to a typical value for pulsars.

Currently the pulsar is moving south from the plane of the Milky Way galaxy, but because it is moving more slowly than the escape velocity of the Galaxy, it will eventually curve back towards the plane of the Galaxy in the opposite direction.

Source: NASA

Posted on by Nancy Atkinson

MRO Goes Into Safe Mode

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NASA’s Mars Reconnaissance Orbiter unexpectedly rebooted its computer Monday morning, Feb. 23, and put itself into a limited-activity mode, an automated safety response to an anomalous event such as a cosmic ray hit on part of the electronics on board the spacecraft. This is the fifth time since August of 2005 that the spacecraft has gone into safe mode. However, the symptoms from this week’s event do not match any of the prior safe-mode events. “We are going to bring the spacecraft back to normal operations, but we are going to do so in a cautious way, treating this national treasure carefully,” said Jim Erickson of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., project manager for the Mars Reconnaissance Orbiter. “The process will take at least a few days.”

Safe Mode is a precaution programmed for the spacecraft when it senses a condition for which it does not know a more specific response.

MRO engineers are examining possible causes of the event while planning to prepare the spacecraft to resume its scientific investigations of Mars. There has been no reoccurrence of the reboot event.

The spacecraft is in communication with and under control by the flight team. Its batteries are charged and its solar panels are properly generating electricity. The team successfully commanded an increase of more than 10,000-fold in the communication rate Monday afternoon from the rate of 40 bits per second that the orbiter initially adopted when it went into the precautionary “safe” mode.

From the spacecraft data received after communications accelerated, the team gained a preliminary indication that the cause of the reboot might have been a measurement — possibly erroneous — of a brief increase in power load. The event lasted between 200 nanoseconds and 41 seconds. That leads engineers to identify one possible scenario as a cosmic-ray hit that could have caused an erroneous voltage reading that would last 9 microseconds, enough to trigger the reboot.

The reboot occurred at about 4:25 a.m. Pacific Standard Time on Monday, while the orbiter was behind Mars from Earth’s perspective. Engineers hope to have MRO back functioning normally by early next week.

Source: NASA

Posted on by Anne Minard

Titan Dunes Turn Climate Models Upside Down

Map of dunes on Titan, with arrows indicating the general wind direction. Dark areas without arrows might have dunes but have not yet been imaged with radar. Credit: NASA/JPL/Space Science Institute (Boulder, Colorado)

Scientists have mapped vast dune fields on Titan that may align with the wind on Saturn’s biggest moon — flowing opposite the way climate models had predicted.

The maps, as above, represent four years of radar data collected by the Cassini spacecraft. They reveal rippled dunes that are generally oriented east-west, which means Titan’s winds probably blow toward the east instead of the west. If so, Titan’s surface winds blow opposite the direction suggested by previous global circulation models. On the example above, the arrows indicate the general wind direction. The dark areas without arrows might have dunes but have not yet been imaged. 

“At Titan there are very few clouds, so determining which way the wind blows is not an easy thing, but by tracking the direction in which Titan’s sand dunes form, we get some insight into the global wind pattern,” says Ralph Lorenz, Cassini radar scientist at Johns Hopkins University in Maryland. “Think of the dunes sort of like a weather vane, pointing us to the direction the winds are blowing.”

Titan’s dunes are believed to be made up of hydrocarbon sand grains likely derived from organic chemicals in Titan’s smoggy skies. The dunes wrap around high terrain, which provides some idea of their height. They accumulate near the equator, and may pile up there because drier conditions allow for easy transport of the particles by the wind. Titan’s higher latitudes contain lakes and may be “wetter” with more liquid hydrocarbons, not ideal conditions for creating dunes.

“Titan’s dunes are young, dynamic features that interact with topographic obstacles and give us clues about the wind regimes,” said Jani Radebaugh, from Brigham Young University in Utah. “Winds come at these dunes from at least a couple of different directions, but then combine to create the overall dune orientation.”

Researchers say the wind pattern is important for planning future Titan explorations that might involve balloon-borne experiments. Some 16,000 dune segments were mapped out from about 20 radar images, digitized and combined to produce the new map, which is available at http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini. A paper based on the new findings appeared in the Feb. 11 issue of Geophysical Research Letters.

Cassini, which launched in 1997 and is now in extended mission operations, continues to blaze its trail around the Saturn system and will visit Titan again on March 27. Seventeen Titan flybys are planned this year.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA’s Jet propulsion Laboratory (JPL) in Pasadena, California manages the Cassini-Huygens mission. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

LEAD IMAGE CREDIT: NASA/JPL/Space Science Institute (Boulder, Colorado)

Source: NASA

Posted on by Tammy Plotner

Weekend SkyWatcher’s Forecast: February 27 – March 1, 2009

Greetings, fellow SkyWatchers! Are you ready for the weekend? Then let’s tackle both fun and serious studies as we take on a bright open star cluster, Herschel 400 objects, lunar subjects, planets, comets and even a galaxy cluster. If you’re ready to learn more about the history behind the observing and have some fun under the stars, then just follow me…

lyotFriday, February 27, 2009 – Today let’s celebrate the 1897 birth on this date of Bernard Lyot, master of optics. He invented the polariscope, and produced the first solar coronagraph. He also made the first motion pictures of solar prominences. Lyot was an astute observer, and realized that the lunar surface had similar properties to volcanic dust. He didn’t see canals on Mars but observed sandstorms there, as well as atmospheric conditions on other planets. The Lyot filter is well known, and so is his micrometer, a device used to make precise distance measurements, especially those between close double stars. By all accounts a wonderful and generous man, Lyot sadly died of a heart attack while returning from seeing an eclipse.

1m47

Honor Lyot’s work by studying two open clusters, found about a fist-width north of Xi Puppis. The brighter of the two – M47 (RA 07 36 36 Dec -14 29 00) – is 1,600 light-years away and a glorious object for binoculars. Filled with mixed-magnitude stars that resolve fully to aperture, M47 features the matched-magnitude double star Struve 1211 near its center. For all its bright beauty, this stellar swarm has the most ironic of histories. Probably discovered first by Hodierna but kept secret, it was independently recovered by Charles Messier, but its position was logged incorrectly. Later, it was cataloged by both William and Caroline Herschel. . .and yet again by John Herschel, who said: ‘‘This cluster has not since been observed. It is probably very loose and poor one.’’ Even Dreyer had a hard time nailing it down! Funny, considering it has only been there for 78 million years…

ngc2423While M47 is a Herschel object, look just slightly north (about a field of view) to pick up another cluster that borders it, NGC 2423 (RA 07 40 45 Dec -9 09 00). This compressed cluster contains more than two dozen faint stars with a lovely golden binary at its center. By comparing the two clusters telescopically, you are also expanding your own studies by viewing two different types of stellar evolution: M47 is very similar to the Pleiades, while NGC 2423 more closely resembles the Hyades.

Saturday, February 28, 2009 – If you didn’t notice the beautiful visage of the tender young Moon and Venus last night at sunset, try again tonight. The pair will be even closer! For most observers, Venus will be only slightly more than a degree away from the Moon’s limb. Have you checked Venus’s phase in the telescope lately? Just like our own Moon, the inner planets (Mercury and Venus) have phases. Because they’re inside Earth’s orbital path, we only see a thin crescent when they first emerge from the Sun’s glare, and they become gibbous as they are about to pass behind the Sun from our point of view. That’s also the reason why we only see these two planets either after sunset or before sunrise!

vendelinus

Take a closer look at the slender crescent Moon. It, too, has only just emerged from the Sun’s glare, and now is the time to get a great look at two craters – Langrenus and Vendelinus. If you remember Mare Fecunditatis, you won’t have any trouble spotting Langrenus on its south shore about mid-way along the Moon’s visible limb. It’s a very old crater with an approximate diameter of 132 kilometers, and appears to binoculars as a shallow, bright ring; featuring a central peak. Further south is equally old Vendelinus. Slightly larger and spanning 147 kilometers, it will appear even more shallow – because it is. It lacks a central peak, but telescopes at high power can resolve its few minor interior craters.

ngc2506Keep your binoculars or telescopes out for a while after the Moon sets, and let’s head a little less than a fist-width east-southeast of Alpha Monocerotis (RA 08 00 01 Dec -10 46 12) to check out NGC 2506. On a dark night, this nearly 7th magnitude object is one of the most impressive of the Monoceros open star clusters. Caught in a chain of stars, it displays a rich concentration, almost appearing like a globular cluster. NGC 2506 has been used to study old, metal-poor galactic clusters. Evolution has enriched its iron content, and – despite its extreme age – it is still a beauty. Be sure to mark your Hershel ‘‘400’’ notes!

Sunday, March 1, 2009 – In 1966, Venera 3 became the first craft to touch another planet when it impacted Venus on this date. Although communications failed before it could transmit data, it was still a milestone achievement. If you’re out at sunset, be sure to have a look at Venus and say “Spaseba!”

cleomides

Once you’ve viewed Venus, let’s turn our observations toward tonight’s Moon and begin by identifying some prominent lunar craters around Mare Crisium that can be spotted easily with a small telescope. North you’ll spy Cleomides and at the western edge, Proclus. Near the terminator northwest is Macrobius, and southwest is Taruntius. Power up and identify the small wells of Peirce, Picard, and Lick inside the smooth sands of Crisium. Lather, rinse and repeat… The more often you repeat crater names to yourself (and aloud) the greater the chances are that you’ll retain these names in your memory. Now, let the Moon wester and we’ll go again…

omearaIn 2003, another Deep-Sky Companion book by notable observer and author Stephen O’Meara premiered. Known for his high-quality sketches of Solar System objects and uncanny observing skills, O’Meara was the first to sight Comet Halley in 1985, and sketch the dark spokes in Saturn’s rings (before Voyager had imaged them). Still part of the editorial staff at Sky & Telescope, and a treasured lecturer, let’s take just a moment to congratulate Steve on a lifetime of achievement! (folks? you will never meet a more genuinely kind person and one who treats fellow amateur astronomers with such huge respect. i have met a great many of my astronomy “heroes” over the years and steve-o is most definitely the kind of star i’d like to be some day.)

Are you ready to practice Steve’s powers of observation? Then begin with Comet Lulin – now speeding in the eastern edge of the dim constellation of Cancer. If you have difficulty finding it, look for the large, backwards question mark of the prominent asterism of Leo. The bright star you see that’s the “period” of the question mark is Regulus – and Comet Lulin is a couple of binocular fields west. Once you’ve spied it, try comparing details to what you may have observed of Lulin’s previous behavior and appearance. Is the comet moving faster than when you first began observing it? It the tail longer? Brighter? What direction does it point in? Has the coma become more diffuse or larger? Does the comet display a nucleus? Is the anti-tail still visible? Asking yourself simple questions like these will help you become a far better observer!

saturnNow wait until Saturn has cleared the horizon murk and let’s take a close look at this fascinating planet. Look for details such as ring shadows on the planet and planet shadows on the rings. Can you see the Casinni Division? How about Saturn’s satellites? Tonight you’ll find Titan leading the way well outside to the west. To the western ring edge, you’ll see Tethys… And clustered together on the eastern ring edge are Rhea, Dione and Enceladus. You won’t need the Hubble Space Telescope to see these kinds of details – just a steady sky and around a 4″ telescope. Take your time and enjoy your studies!

abell_george_a1Ready for some serious studies? Then let’s talk about George Abell, who was born this day in 1927. Abell was responsible for cataloging 2,712 clusters of galaxies from the Palomar sky survey, a task he completed in 1958. Using these plates, Abell proposed that the grouping of such clusters delineated the arrangement of matter in the universe. He developed the luminosity function, which shows the relationship between brightness and the number of members in each cluster, allowing you to infer the cluster’s distance. Abell also discovered planetary nebulae, and developed the theory (along with Peter Goldreich) of their evolution.

abell1367For seasoned observers, wait until the Moon has set and honor Abell by viewing one of his galaxy clusters – Abell 1367, located about a degree southwest of 93 Leonis (RA 11 44 44 Dec +19 41 59). It’s an area of challenging intrigue for a large scope – spanning a degree of sky and containing as many as two dozen small galaxies – a gemstone for the galaxy collector!

Until next week? Ask for the Moon… But keep on reaching for the stars!

This week’s awesome images are: Bernard Lyot (public image), M47 and NGC 2423 (Credit: Palomar Observatory, courtesy of Caltech), Langrenus and Vendelinus (Credit: Dave Nash), NGC 2506 (credit – Palomar Observatory, courtesy of Caltech), Crisium area (Credit: Greg Konkel), Stephen James O’Meara (Credit: Sky & Telescope), Saturn & Moons (Credit: NASA), George Abell (Credit: American Institute of Physics), Abell 1367 (Credit: Palomar Observatory, courtesy of Caltech). We thank you so much for sharing the history and mystery with us!

Posted on by Ian O'Neill

Obama Will Retire Shuttle in 2010, US Will Go Back to the Moon in 2020

This could still happen in 2020 (NASA)

[/caption]In a budget blueprint released by the White House on Thursday, President Barack Obama has confirmed his intent to carry out the planned retirement of the ageing Space Shuttle next year. Additionally, the the blueprint affirms Obama’s stance on a return trip to the Moon. The US will return to the lunar surface by the year 2020, following the time scale set out by George W. Bush’s 2004 Vision for Space Exploration. However, there is no mention that the next manned lunar mission will be carried out by the Constellation Program, a project plagued by criticism about its design and technology.

Although the blueprint may differ from the final budget submitted to Congress in April, it looks like there is some certainty about the future of the shuttle and the direction NASA will be taking over the next decade. And now the space agency has a little bit more money to do something about that troublesome 5-year gap in US manned access to space…

So, any hope to extend the life of the Shuttle looks to have been dashed. Although there could still be a chance for a shuttle extension when the final budget is submitted, it seems as if President Obama has made his intent very clear; the 25 year-old space launch system will be mothballed, as planned, in 2010. This may come as a relief to many as extending the operational lifetime of the shuttle could be a safety risk, however, many on Florida’s Space Coast won’t be so happy as they could be looking at losing their jobs sooner than they would have hoped.

Generally, these decisions have been welcomed, including the extra $2.4 billion NASA will receive for the 2010 fiscal year (when compared with 2008):

Combined with $1 billion provided to NASA in the $787 billion stimulus package signed into law Feb. 17, the agency would receive $2 billion more than in the $17.7 billion 2009 NASA budget that was passed by the House – an increase that equals an Obama campaign promise. — Florida Today

It remains uncertain how the gap between shuttle retirement and Constellation launch could be shortened from the minimum of five years, but the extra cash is bound to boost confidence. But where does the blueprint say Constellation is even part of the plan? It doesn’t, sparking some media sources to point out that it remains a possibility that the Ares rocket system could be abandoned in favour of making the existing Atlas V or Delta IV rockets human rated. However, space policy specialists are advising not to read too much into the omission.

“The budget doesn’t say a whole lot about any specific system,” said John Logsdon, a space policy analyst at the National Air and Space Museum in Washington, DC. “I wouldn’t interpret the absence of the words ‘Constellation’, ‘Ares’, and ‘Orion’ one way or another. That’s really up to the the new management team, when it gets there.”

After all, since the departure of Michael Griffin as NASA Administrator, the space agency has been without a leader. Acting NASA Administrator Christopher Scolese is currently at the helm, saying that the new budget “is fiscally responsible and reflects the administration’s desire for a robust and innovative agency.” Unfortunately the details about the use of Constellation may remain sketchy until the final budget is submitted.

This may be the case, but President Obama has obviously seen the merit in the original plans to get man back to the Moon by the year 2020, despite criticism from a guy who has actually stood on the Moon, Buzz Aldrin. In an “alternative” proposal for the future of NASA, Aldrin and two co-authors posted a draft of the “Unified Space Vision” on the National Space Society’s website this week (Update: the draft has now been “Removed At Request of the Authors”), urging the administration not to mount an unnecessary lunar mission (been there, done that) and go straight for manned exploration of the asteroids and Mars. The Unified Space Vision, unfortunately, was probably too hard on NASA’s accomplishments, saying that “post-Apollo NASA” has become a “visionless jobs-providing enterprise that achieves little or nothing,” in developing a viable space transportation system. Many of the points raised are valid (and occasionally very tough), but would require a complete change in NASA’s structure to accomplish. I doubt we’ll see any radical changes being enacted any time soon.

So, we now have a pretty good idea as to what’s going to happen to the shuttle next year; it looks like the plan to get the US back to the Moon by 2020 is still on and NASA has been given an extra $2 billion to play with. I hope they spend it wisely, perhaps on private space launch contracts?

Sources: Florida Today, New Scientist

Posted on by Nancy Atkinson

Intergalactic Dust Could Be Messing Up Observations, Calculations

Spiral galaxies seen edge-on often show dark lanes of interstellar dust blocking light from the galaxy's stars, as in this image of the galaxy NGC 4565 from the Sloan Digital Sky Survey (SDSS-II).

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“Just like household dust, cosmic dust can be a nuisance,” said astronomer Ryan Scranton of the University of California, Davis. Scranton is part of a team of researchers from the Sloan Digital Sky Survey that have been analyzing the colors of distant quasars whose light passes in the vicinity of foreground galaxies on its way to the Earth. What they found is that the vast expanses of intergalactic space appear to be filled with a haze of tiny, smoke-like “dust” particles that dim the light from distant objects and subtly change their colors. “Galaxies contain lots of dust, most of it formed in the outer regions of dying stars,” said team leader Brice Ménard of the Canadian Institute for Theoretical Astrophysics. “The surprise is that we are seeing dust hundreds of thousands of light-years outside of the galaxies, in intergalactic space.”

An implication of this finding means that since most distant supernovae are seen through some haze, our current estimates of their distances may be affected.

Dust grains block blue light more effectively than red light. “We see this when the sun sets: light rays pass through a thicker layer of the atmosphere,” said Scranton, “absorbing more and more blue light, causing the sun to appear reddened. We find similar reddening of quasars from intergalactic dust, and this reddening extends up to ten times beyond the apparent edges of the galaxies themselves.”

The team analyzed the colors of about 100,000 distant quasars located behind 20 million galaxies, using images from SDSS-II. “Putting together and analyzing this huge dataset required cutting-edge ideas from computer science and statistics,” said team member Gordon Richards of Drexel University. “Averaging over so many objects allowed us to measure an effect that is much too small to see in any individual quasar.”

Supernova explosions and “winds” from massive stars drive gas out of some galaxies, Ménard explained, and this gas may carry dust with it. Alternatively, the dust may be pushed directly by starlight.

“Our findings now provide a reference point for theoretical studies,” said Ménard.

Intergalactic dust could also affect planned cosmological experiments that use supernovae to investigate the nature of “dark energy,” a mysterious cosmic component responsible for the acceleration of the expansion of the universe.

Intergalactic dust doesn’t remove the need for dark energy to explain current supernova data, Ménard explained, but it may complicate the interpretation of future high-precision distance measurements. “These experiments are very ambitious in their goals,” said Ménard, “and subtle effects matter.”

The new findings are reported in a paper titled “Measuring the galaxy-mass and galaxy-dust correlations through magnification and reddening,” submitted to the journal Monthly Notices of the Royal Astronomical Society, and posted today on the web site arXiv.org.

Source: Sloan Digital Sky Survey

Posted on by Tammy Plotner

Comet Lulin Video – Watch the Outgassing Process

Roughly 38 million miles from Earth and traveling at a relative velocity of 140,000 miles per hour, the speedy Comet C/2007 N3 Lulin has caught our imaginations in a big way during the beginning months of the International Year of Astronomy. Right now, Comet Lulin has already sped past the Sun, slipped by stately Saturn from our point of view and is on a parabolic trajectory heading out from our solar system. This means it will never come back… Continue reading “Comet Lulin Video – Watch the Outgassing Process”