Cosmic Curiosity Reveals Ghostly Glow Of Dead Quasar

The green Voorwerp in the foreground remains illuminated by light emitted up to 70,000 years ago by a quasar in the center of the background galaxy, which has since died out. (Photo: WIYN/William Keel/Anna Manning)

by Staff Writers

New Haven CT (SPX) Nov 04, 2010

While sorting through hundreds of galaxy images as part of the Galaxy Zoo citizen science project two years ago, Dutch schoolteacher and volunteer astronomer Hanny van Arkel stumbled upon a strange-looking object that baffled professional astronomers.

Two years later, a team led by Yale University researchers has discovered that the unique object represents a snapshot in time that reveals surprising clues about the life cycle of black holes.

In a new study, the team has confirmed that the unusual object, known as Hanny's Voorwerp (Hanny's "object" in Dutch), is a large cloud of glowing gas illuminated by the light from a quasar-an extremely energetic galaxy with a supermassive black hole at its center.

The twist, described online in the Astrophysical Journal Letters, is that the quasar lighting up the gas has since burned out almost entirely, even though the light it emitted in the past continues to travel through space, illuminating the gas cloud and producing a sort of "light echo" of the dead quasar.

"This system really is like the Rosetta Stone of quasars," said Yale astronomer Kevin Schawinski, a co-founder of Galaxy Zoo and lead author of the study. "The amazing thing is that if it wasn't for the Voorwerp being illuminated nearby, the galaxy never would have piqued anyone's interest."

The team calculated that the light from the dead quasar, which is the nearest known galaxy to have hosted a quasar, took up to 70,000 years to travel through space and illuminate the Voorwerp-meaning the quasar must have shut down sometime within the past 70,000 years.

Until now, it was assumed that supermassive black holes took millions of years to die down after reaching their peak energy output.

However, the Voorwerp suggests that the supermassive black holes that fuel quasars shut down much more quickly than previously thought.

"This has huge implications for our understanding of how galaxies and black holes co-evolve," Schawinski said.

"The time scale on which quasars shut down their prodigious energy output is almost entirely unknown," said Meg Urry, director of the Yale Center for Astronomy and Astrophysics and a co-author of the paper.

"That's why the Voorwerp is such an intriguing-and potentially critical-case study for understanding the end of black hole growth in quasars."

Although the galaxy no longer shines brightly in X-ray light as a quasar, it is still radiating at radio wavelengths. Whether this radio jet played a role in shutting down the central black hole is just one of several possibilities Schawinski and the team will investigate next.

"We've solved the mystery of the Voorwerp," he said. "But this discovery has raised a whole bunch of new questions."

Other authors of the paper include Shanil Virani, Priyamvada Natarajan, Paolo Coppi (all of Yale University); Daniel Evans (Massachusetts Institute of Technology, Harvard-Smithsonian Center for Astrophysics and Elon University); William Keel and Anna Manning (University of Alabama and Kitt Peak National Observatory); Chris Lintott (University of Oxford and Adler Planetarium); Sugata Kaviraj (University of Oxford and Imperial College London); Steven Bamford (University of Nottingham); Gyula Jozsa (Netherlands Institute for Radio Astronomy and Argelander-Institut fur Astronomie); Michael Garrett (Netherlands Institute for Radio Astronomy, Leiden Observatory and Swinburne University of Technology); Hanny van Arkel (Netherlands Institute for Radio Astronomy); Pamela Gay (Southern Illinois University Edwardsville); and Lucy Fortson (University of Minnesota). Citation: Kevin Schawinski et al 2010 ApJ 724 L30 DOI: 10.1088/2041-8205/724/1/L30

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Electrical malfunction delays Discovery launch to Thursday

by Staff Writers
Cape Canaveral, Florida (AFP)
An electrical malfunction has forced the US space agency to delay until Thursday the shuttle Discovery's final mission to the International Space Station, NASA said.

"Space shuttle Discovery's launch on the STS-133 mission has been delayed until no earlier than Thursday," NASA said in a statement.

The mission, initially scheduled for Monday, has been postponed three times.

Earlier delays were announced so that Kennedy Space Center technicians could repair quick-disconnect fittings in the system used to pressurize one of Discovery's orbital maneuvering rocket engines.

earlier related report
Shuttle Discovery counts down to final space voyage
Washington (AFP) Oct 31, 2010 - Discovery, the oldest space shuttle in NASA's fleet, is readying for its final mission Wednesday following repairs to leaks in a pressurization system that has twice delayed the launch.

"Work is on schedule. We completed flight pressurization and all went well. That is behind us now," Steve Payne, NASA test director, told reporters as the countdown to launch kicked off at 2:00 pm (1800 GMT) Sunday.

The mission, initially scheduled for Monday, was postponed so Kennedy Space Center technicians could repair quick-disconnect fittings in the system used to pressurize one of Discovery's orbital maneuvering rocket engines.

Discovery and its six American astronauts will now launch from Florida's Kennedy Space Center at 3:52 pm (1952 GMT) Wednesday bound for the International Space Station (ISS).

The weather forecast remains 70 percent for favorable conditions, Kathy Winters, Cape Canaveral's senior meteorologist, said at a press briefing, adding that there were slight concerns of possible rain and clouds in the launch area.

The flight to the orbiting ISS is the fourth and final shuttle flight of the year, and the last scheduled for Discovery, the oldest in the three-shuttle fleet that is being retired in 2011.

Discovery has been the busiest shuttle in history, with a record 38 trips into space since its first launch in 1984. According to NASA, it has traveled over 142 million miles (228 million kilometers) during that time, involving 5,628 orbits of the Earth over 351 days.

NASA has long relied on the Discovery spacecraft at key points along its 26-year career -- the launch of the Hubble Space Telescope in 1990, the first ever female shuttle pilot Eileen Collins in 1995, and in 1998 it carried US space icon John Glenn to become the oldest human to fly in space at age 77.

Its all-American crew on this voyage, including female mission specialist Nicole Stott, will deliver a pressurized logistics module called Leonardo, which will be permanently attached to the space station to give it more storage space.

The shuttle will also bring Robonaut 2, the first human-like robot in space, and a permanent addition to the orbiting space station, as well as spare parts.

Two space walks, for maintenance work and component installation, are scheduled.

The three US shuttles -- the other two are Atlantis and Endeavour -- are due to be sent off to become museum pieces after a final shuttle mission to the space station in late February.

That means Russian Soyuz spacecraft, a modernized version of which recently dropped off three fresh crew members to the ISS, doubling the crew to six, will for several years be the only vehicle for transporting humans into space.

However, NASA's recently approved 2011 budget has left the door open to an additional shuttle flight in June.

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China Goes To Mars

Mars Orbital Insertion will be a significant achievement for China's growing space science program.

by Morris Jones
Sydney, Australia (SPX) Oct 31, 2010
As China's second Moon probe continues its mission, more information is being disclosed about China's ambitions for worlds beyond. China has made no secret of its plans to explore Mars, but we are getting a firmer indication of what to expect.

Vague statements in the Chinese media have suggested that China could launch a mission to Mars in 2013. This is an interesting suggestion for a program that's still largely unknown to us. How does this add to our knowledge of China's Mars program?

China's first planned step to Mars is very well known. In 2011, the Yinghuo 1 orbiter will be launched to Mars in tandem with Russia's Phobos-Grunt mission. We know a lot about Yinghuo 1 already, thanks to some fairly open publicity about the mission. Yinghuo 1 is a small orbiter, which will enter a highly elliptical orbit around Mars.

Its main role is to study the tenuous Martian atmosphere, and help to answer one of the greatest mysteries surrounding the planet. Long ago, the atmosphere of Mars was much thicker, helping to produce almost Earthlike conditions on the surface. Why did Mars change into the barren world of today, and why did most of the atmosphere disappear?

Roughly two years after Yinghuo 1 is launched, a new "launch window" will open between Earth and Mars, as the position of the planets becomes favourable again. NASA plans to send an orbiter during this window, and it will also study the Martian atmosphere. Could China be ready to fly again so soon?

There are plenty of reasons to believe that China could do it. Consider recent events. China has successfully carried out a long mission in deep space. The Chang'e 1 mission was China's first lunar orbiter. Launched in 2007, the spacecraft performed well in mapping the entire Moon.

China has followed this with the launch of Chang'e 2 just a few weeks ago. This spacecraft is essentially a copy of Chang'e 1, with different instruments and some improvements to its sub-systems. Chang'e 2 is performing very well, and has navigated successfully into a low lunar orbit. Chinese space engineers must feel pleased. They've developed a generic spacecraft design and proven that it works well, on two flights out of two.

China has also openly discussed the possibility of sending Chang'e 2 beyond the Moon once its primary mission is complete. While the spacecraft will not be sent to Mars, it has been suggested that Chang'e 2 could be sent into heliocentric orbit, to test communications and control at vast distances from Earth. This is another hint at what China is planning.

This author suggests that the basic spacecraft bus used for the Chang'e lunar orbiters could be modified for use as a Chinese Mars probe. The Chang'e bus, or main spacecraft body, is itself derived from a geostationary communications satellite. Engineers love evolution, taking something that works and modifying it for other purposes. From Earth orbit, to the Moon, to Mars, is the steady path of this robust spacecraft design.

A dedicated Mars mission would require further modifications to the design of the spacecraft. There would need to be changes to the antennas and telemetry systems used, to compensate for the greater distance. One of the changes in Chang'e 2 over its predecessor is the use of a new, advanced radio system with different frequencies. Could this be a precursor of something designed to work at Mars?

Flying to the Moon is, technically speaking, a trip into deep space. But a flight all the way to Mars could expose a spacecraft to even more hazards. The spacecraft could probably use some additional hardening of some of its key components, even if this is just placing extra cosmic ray shielding on the computer.

Getting to Mars requires more energy than a mission to the Moon. China used the Long March 3A for the first Chang'e launch, and then switched to the more powerful Long March 3C for the second. But even this rocket would struggle to send a Chang'e-type probe to Mars.

It's entirely possible, however, that the Long March 3B could do it. Despite its lower alphabetical rank, this rocket is more powerful than the 3A or 3C, and draws much of its extra force from the use of four strap-on rocket boosters. If China really wanted a big boost, it could use the stretched variant of this rocket, the Long March 3B/E.

Right now, this is the most powerful booster in China's fleet. More powerful boosters will be available to China when the Long March 5 family of boosters makes its debut, but this is unlikely to happen before 2014. If China wants to fly to Mars in 2013, the well-tested Long March 3B will be the best choice.

So, we have a rocket that can reach Mars and a spacecraft design that can fly there. What else needs to be addressed? China has a large stable of scientific instruments at its disposal. Some have been tested on the Chang'e missions. Some are already going to Mars on board Yinghuo.

A large Mars orbiter will need a high-resolution camera (currently on Chang'e 2), spectrometers (Chang'e 1 and 2) and some particles and fields instruments (Yinghuo 1 and various Chinese scientific satellites). China just needs to pick and choose.

Then there's the tracking and support. China has already demonstrated the ability to track and communicate with spacecraft at the Moon. Through its co-operation with the European Space Agency, it has access to a global deep space network, and can also tap European experience in tracking planetary missions. Control and navigation of both Chang'e missions was impressive.

When all the recent progress in China's unmanned space program is considered, the idea of launching an advanced Mars mission within three years does not sound farfetched. But China could elect to wait for another launch window, and refine some of its mission goals and hardware.

There are also ambitious feats in the works for China's lunar program, with a robot lunar landing expected in 2012. China is also planning its first small manned space laboratory, which should also receive its first crew in 2012. There's plenty of activity in the near future without going to Mars.

Even if China does not launch its second Mars mission in 2013, the very fact that it can be considered is instructive. It points to a growing confidence in China's spaceflight capabilities, and also gives hints to the type of hardware that would probably be used. As usual, time will reveal the answers to these questions.

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Inexpensive orbital launches described

disclaimer: image is for illustration purposes only

by Staff Writers
Washington (UPI) Oct 25, 2010
A U.S. company says it wants to offer inexpensive launch capabilities to dozens of universities and organizations hoping to put small satellites into orbit.

Currently, these mini-satellites must go as piggyback secondary payloads on large rocket launch missions, giving the satellite owners little choice over the timing of a launch or the final orbital positioning, SPACE.COM reports.

"Getting reasonable cost access [to space] for small spacecraft is really critical," says Kris Kimel, president of Kentucky Space, a private-public consortium hoping to launch its first small orbital satellite in 2011. "We need to get that kind of access that allows us to relentlessly innovate and quite frankly to fail more."

A start-up company called NanoLauncher proposes to provide that access using existing technology in the form of decommissioned military aircraft that will carry the satellites on a small rocket to be launched at high altitude to head to Earth orbit.

Jets under consideration for the NanoLauncher program include the Lockheed F-104 Starfighter and the McDonnell Douglas F-15D Eagle, which would take the small satellite slung underneath their fuselage on a rocket to an altitude of several miles up then launch the rocket to send the payload to its intended destination above Earth.

NanoLauncher says it expects to begin full-scale operations sometime in 2014.

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Space tourism ticket prices could drop

disclaimer: image is for illustration purposes only

by Staff Writers
Houston (UPI) Oct 25, 2010
Two space tourism companies say the price for a trip into space could drop from millions of dollars down to hundreds of thousands by late 2011.

A brief trip into space featuring a few minutes of weightlessness and a view of the earth 62 miles below could be within reach of the merely well-off and not just the mega-rich, the Houston Chronicle reported Monday.

"Now, the sky is no longer the limit," said Richard Branson, whose Virgin Group is one the companies planning to offer commercial suborbital missions late next year. "We will begin the process of pushing beyond to the final frontier of space itself."

Space Adventures, the Vienna, Va.-based company that brokered the flights of seven space tourists to the International Space Station between 2001 and 2009, also plans to offer suborbital tourist flights.

Both companies are expected to offer tickets at between $100,000 and $200,000, still a steep price for a flight lasting a few minutes.

"There's no magic wand out there to wave and reduce the cost of space access by a factor of 10 or 100," said Jeff Foust, a space industry analyst for the Futron Corp.

The big hope in space tourism, he said, is that once suborbital flights grow in demand ticket prices will drop.

"It's not going to be something where it's a $99 deal with Southwest," Foust said. "Relative to commercial air travel it will still be expensive. But people spend tens of thousands of dollars to climb Everest, visit Antarctica or go on African safaris. This price will attract adventure tourists."

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Planet Hunters No Longer Blinded By The Light

The planet Beta Pictoris b imaged using the Apodizing Phase Plate coronagraph. The "bad" (bright) side of the image is visible to the right while the central bright regions of the central star (Beta Pictoris) have been masked out to enable the viewer to clearly see the planet to the left of the star. Credit: European Southern Observatory (ESO)

by Staff Writers
Tucson AZ (SPX) Oct 20, 2010
Using new optics technology developed at the University of Arizona's Steward Observatory, an international team of astronomers has obtained images of a planet on a much closer orbit around its parent star than any other extrasolar planet previously found.

The discovery, published online in Astrophysical Journal Letters, is a result of an international collaboration among the Steward Observatory, the Swiss Federal Institute of Technology Zurich, the European Southern Observatory, Leiden University in the Netherlands and Germany's Max-Planck-Institute for Astronomy.

Installed on the European Southern Observatory's Very Large Telescope, or VLT, atop Paranal Mountain in Chile, the new technology enabled an international team of astronomers to confirm the existence and orbital movement of Beta Pictoris b, a planet about seven to 10 times the mass of Jupiter, around its parent star, Beta Pictoris, 63 light years away.

At the core of the system is a small piece of glass with a highly complex pattern inscribed into its surface. Called an Apodizing Phase Plate, or APP, the device blocks out the starlight in a very defined way, allowing planets to show up in the image whose signals were previously drowned out by the star's glare.

"This technique opens new doors in planet discovery," said Phil Hinz, director of the UA's Center for Astronomical Adaptive Optics at Steward Observatory. "Until now, we only were able to look at the outer planets in a solar system, in the range of Neptune's orbit and beyond. Now we can see planets on orbits much closer to their parent star."

In other words, if alien astronomers in another solar system were studying our solar system using the technology previously available for direct imaging detection, all they would see would be Uranus and Neptune. The inner planets, Mercury, Venus, Earth, Mars and Saturn, simply wouldn't show up in their telescope images.

To put the power of the new optics system in perspective: Neptune's mean distance from the sun is about 2.8 billion million miles, or 30 Astronomical Units, or AUs. One AU is defined as the mean distance between the sun and the Earth.

The newly imaged planet, Beta Pictoris b, orbits its star at about seven AUs, a distance where things get especially interesting, according to Hinz, "because that's where we believe the bulk of the planetary mass to be in most solar systems. Between five and 10 AUs."

While planet hunters have used a variety of indirect methods to detect the "footprints" of extrasolar planets - planets outside our solar system - for example the slight gravitational wobble an orbiting planet induces in its parent star, very few of them have been directly observed.

According to Hinz, the growing zoo of extrasolar planets discovered to date - mostly super-massive gas giants on wide orbits - represents a biased sample because their size and distance to their parent star makes them easier to detect.

"You could say we started out by looking at oddball solar systems out there. The technique we developed allows us to search for lower-mass gas giants about the size of Jupiter, which are more representative of what is out there."

He added: "For the first time, we can search around bright, nearby stars such as Alpha Centauri, to see if they have gas giants."

The breakthrough, which may allow observers to even block out starlight completely with further refinements, was made possible through highly complex mathematical modeling.

"Basically, we are canceling out the starlight halo that otherwise would drown out the light signal of the planet," said Johanan (John) Codona, a senior research scientist at the UA's Steward Observatory who developed the theory behind the technique, which he calls phase-apodization coronagraphy.

"If you're trying to find something that is thousands or a million times fainter than the star, dealing with the halo is a big challenge."

To detect the faint light signals from extrasolar planets, astronomers rely on coronagraphs to block out the bright disk of a star, much like the moon shielding the sun during an eclipse, allowing fainter, nearby objects to show up.

Using his own unconventional mathematical approach, Codona found a complex pattern of wavefront ripples, which, if present in the starlight entering the telescope, would cause the halo part to cancel out but leave the star image itself intact.

The Steward Observatory team used a machined piece of infrared optical glass about the size and shape of a cough drop to introduce the ripples. Placed in the optical path of the telescope, the APP device steals a small portion of the starlight and diffracts it into the star's halo, canceling it out.

"It's a similar effect to what you would see if you were diving in the ocean and looked at the sun from below the surface," explained Sascha Quanz from the Swiss Federal Institute of Technology's Institute for Astonomy, the lead author of the study.

"The waves on the surface bend the light rays and cause the sky and clouds to appear quite different. Our optic works in a similar way."

In order to block out glare from a star, conventional coronagraphs have to be precisely lined up and are highly susceptible to disturbance. A soft night breeze vibrating the telescope might be all it takes to ruin the image. The APP, on the other hand, requires no aiming and works equally well on any stars or locations in the image.

"Our system doesn't care about those kinds of disturbances," Codona said. "It makes observing dramatically easier and much more efficient."

In the development of APP, Codona was joined by Matt Kenworthy (now at Leiden Observatory in the Netherlands). Hinz, who is a member of the instrument upgrade team for the VLT, played a key role in the technique's implementation on the 6.5 Meter Telescope on Mount Hopkins in Southeastern Arizona.

Former UA astronomy professor Michael Meyer, now at the Swiss Federal Institute of Technology Zurich, where he led the group implementing the technology on the VLT, pointed out that APP is likely to advance areas of research in addition to the hunt for extrasolar planets.

"It will be exciting to see how astronomers will use the new technology on the VLT, since it lends itself to other faint structures around young stars and quasars, too."

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LRO Detects Surprising Gases In LCROSS Lunar Impact Plume

illustration only

by Staff Writers

Boulder CO (SPX) Oct 22, 2010

NASA's Lunar Reconnaissance Orbiter (LRO) and its sophisticated suite of instruments have determined that hydrogen, mercury and other volatile substances are present in permanently shaded soils on the Moon, according to a paper published in Science.

The Lunar Crater Remote Observation and Sensing Satellite (LCROSS), which launched with LRO, was intentionally crashed onto the Moon's surface Oct. 9, 2009, while LRO instruments watched. About 90 seconds after LCROSS hit the Moon, LRO flew past the debris plume raised by the impact, while the Lyman Alpha Mapping Project (LAMP) and other instruments collected data.

Using these data, LAMP team members eventually confirmed the presence of the gases molecular hydrogen, carbon monoxide and atomic mercury, along with smaller amounts of calcium and magnesium, also in gas form.

"We had hints from Apollo soils and models that the volatiles we see in the impact plume have been long collecting near the Moon's polar regions," says Dr. Randy Gladstone, LAMP acting principal investigator, of Southwest Research Institute in San Antonio. "Now we have confirmation."

The point of impact was the Cabeus crater near the lunar south pole. The tiny tilt of the Moon's rotation axis allows the floors of craters near the poles to be permanently shaded from direct sunshine.

Without sunlight, temperatures in these areas can be as low as 35 to 100 Kelvin (degrees above absolute zero) - so cold that almost all volatiles that find their way there become trapped. Ongoing micrometeorite impacts cover them with dirt, further isolating them from exposure and possible escape.

LRO's findings are valuable to the future consideration of robotic and manned Moon base locations.

Just as the poles have nearby crater floors with permanently shaded regions because of the Moon's orientation to the Sun, they also have nearby mountains and crater rims that are in nearly perpetual sunlight, which would enable the placement and operation of solar-powered systems and equipment.

The discovery of water-ice and other resources in the region could also reduce the need to transport resources from Earth for use by astronauts.

"The detection of mercury in the soil was the biggest surprise, especially that it's in about the same abundance as the water detected by LCROSS," says Kurt Retherford, LAMP team member, also of SwRI. "Its toxicity could present a challenge for human exploration."

Developed by Southwest Research Institute, LAMP uses a novel method to peer into the darkness of the Moon's permanently shadowed regions.

The ultraviolet spectrograph observes the nightside lunar surface using light from nearby space (and stars), which bathes all bodies in space in a soft glow.

This Lyman-alpha glow is invisible to human eyes, but visible to LAMP as it reflects off the Moon. Analyses of the emissions, in collaboration with other LRO instruments, help determine lunar surface properties.

Following the LCROSS impact observations, LAMP continues its investigation of the ultraviolet reflectance properties and composition of the lunar surface and the composition of the lunar atmosphere.

Since the conclusion of a one-year reconnaissance mission under NASA's Exploration Systems Mission Directorate, the Science Mission Directorate has assumed oversight of more in-depth investigations for the science instruments. During the science investigation, LAMP will shift into more detailed evaluations of the Moon's atmosphere and its variability.

The paper, "LRO-LAMP Observations of the LCROSS Impact Plume," by G.R. Gladstone, D.M. Hurley, K.D. Retherford, P.D. Feldman, W.R. Pryor, J.-Y. Chaufray, M. Versteeg, T.K. Greathouse, A.J. Steffl, H. Throop, J.W. Parker, D.E. Kaufmann, A.F. Egan, M.W. Davis, D.C. Slater, J. Mukherjee, P.F. Miles, A.R. Hendrix, A. Colaprete, and S.A. Stern, was published in the Oct. 22 issue of Science.

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