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.

www.spacedaily.com

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."

www.space-travel.com

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."

spacedaily.com

LRO Detects Surprising Gases In LCROSS Lunar Impact Plume

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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.

space-travel.com

Astronomer Employs HPC To Peer Into Cosmic Mysteries

Three-panel surface density maps from three different simulations of the final stellar configurations of dwarf galaxies.

by Staff Writers
Columbus OH (SPX) Oct 20, 2010
An Ohio State University astronomer is working to unlock some of the mysteries surrounding the formation of vast galaxies and the evolution of massive black holes with his own large constellation of silicon wafers.

Over the last year, two research teams led by Stelios Kazantzidis, a Long-Term Fellow at the Center for Cosmology and Astro-Particle Physics (CCAPP) at The Ohio State University, have used what would average out to nearly 1,000 computing hours each day on the parallel high performance computing systems of the Ohio Supercomputer Center (OSC).

To develop their detailed models and resulting simulations, Kazantzidis and his colleagues tapped OSC's flagship system, the Glenn IBM Cluster 1350, which features more than 9,600 Opteron cores and 24 terabytes of memory.

Kazantzidis and University of Zurich student Simone Callegari recently authored a paper, "Growing Massive Black Hole Pairs in Minor Mergers of Disk Galaxies," and submitted it for publication in the Astrophysical Journal.

Their study involved a suite of high-resolution, smoothed-particle hydrodynamics simulations of merging disk galaxies with supermassive black holes (SMBHs). These simulations include the effects of star formation and growth of the SMBHs, as well as feedback from both processes.

"Binary SMBHs are very important, because once they form there is always the possibility that the two black holes may subsequently merge," Kazantzidis explained.

"Merging SMBHs will produce the strongest signal of gravitational wave emission in the universe. Gravitational waves have not yet been directly detected, although Einstein predicted them in his Theory of General Relativity."

The astronomers found that the mass ratios of SMBH pairs in the centers of merged galaxies do not necessarily relate directly to the ratios they had to their original host galaxies, but are "a consequence of the complex interplay between accretion of matter (stars and gas) onto them and the dynamics of the merger process."

As a result, one of the two SMBHs can grow in mass much faster than the other.

Kazantzidis believes simulations of the formation of binary SMBHs have the potential to open a new window into astrophysical and physical phenomena that cannot be studied in other ways and might help to verify general relativity, one of the most fundamental theories of physics.

Kazantzidis and his colleagues also recently developed sophisticated computer models to simulate the formation of dwarf spheroidal galaxies, which are satellites of our own galaxy, the Milky Way.

The study concluded that, in a majority of cases, disk-like dwarf galaxies - known in the field as disky dwarfs - experience significant loss of mass as they orbit inside their massive hosts, and their stellar distributions undergo a dramatic morphological, as well as dynamical, transformation: from disks to spheroidal systems.

"These galaxies are very important for astrophysics, because they are the most dark matter-dominated galaxies in the universe," Kazantzidis said.

"Understanding their formation can shed light into the very nature of dark matter. Environmental processes like the interactions between dwarf galaxies and their massive hosts we've been investigating should be included as ingredients in future models of dwarf galaxy formation and evolution."

For this project, Kazantzidis, Callegari, Ewa Lokas of the Nicolaus Copernicus Astronomical Center - all of whom utilized the Glenn Cluster - and the rest of the team have submitted to the Astrophysical Journal an article titled, "On the Efficiency of the Tidal Stirring Mechanism for the Origin of Dwarf Spheroidals: Dependence on the Orbital and Structural Parameters of the Progenitor Disky Dwarfs."

Supercomputing centers such as OSC allow astronomers to create extremely sophisticated models that are not feasible on desktop systems. However, even with supercomputers, Kazantzidis and his colleagues find that simulating the multitude of elements involved in these galactic processes remains an enormous challenge.

"Our models can only follow a small subset of, say, the stars in a galaxy," he explained. "For example, a galaxy like our Milky Way contains hundreds of billions of stars, and even the most sophisticated numerical simulations to date can only simulate a tiny fraction of this number. The situation becomes increasingly more difficult in simulations that involve dark matter.

"This is because the dark matter particle is an elementary particle and, therefore, it is much less massive than a star. A galaxy like the Milky Way contains of the order of 1067 dark matter particles (that is, the number one followed by 67 zeros)."

The goal of Kazantzidis' team is to develop representations of galaxies that are as accurate as possible. Access to the Glenn Cluster increases the number of objects (or simulation particles) that can be depicted in the model, enhancing their ability to perform accurate and meaningful calculations.

"The powerful hardware and software available at OSC are particularly well-suited for cutting-edge astronomy research, such as that being conducted by Dr. Kazantzidis," said Ashok Krishnamurthy, interim co-executive director and director of research at OSC.

"The results he and his colleagues have been able to achieve through their research projects are impressive and firmly demonstrate the Center's ability to help accelerate innovation and discovery."

www.spacedaily.com

How To Weigh A Star Using A Moon

Artist's concept of an exoplanet and its moon transiting a sun-like star. Such a system could be used to directly weigh the star. Credit: David A. Aguilar (CfA)

by Staff Writers

How do astronomers weigh a star that's trillions of miles away and way too big to fit on a bathroom scale? In most cases they can't, although they can get a best estimate using computer models of stellar structure.

New work by astrophysicist David Kipping says that in special cases, we can weigh a star directly. If the star has a planet, and that planet has a moon, and both of them cross in front of their star, then we can measure their sizes and orbits to learn about the star.

"I often get asked how astronomers weigh stars. We've just added a new technique to our toolbox for that purpose," said Kipping, a predoctoral fellow at the Harvard-Smithsonian Center for Astrophysics.

Astronomers have found more than 90 planets that cross in front of, or transit, their stars. By measuring the amount of starlight that's blocked, they can calculate how big the planet is relative to the star. But they can't know exactly how big the planet is unless they know the actual size of the star. Computer models give a very good estimate but in science, real measurements are best.

Kipping realized that if a transiting planet has a moon big enough for us to see (by also blocking starlight), then the planet-moon-star system could be measured in a way that lets us calculate exactly how large and massive all three bodies are.

"Basically, we measure the orbits of the planet around the star and the moon around the planet. Then through Kepler's Laws of Motion, it's possible to calculate the mass of the star," explained Kipping.

The process isn't easy and requires several steps. By measuring how the star's light dims when planet and moon transit, astronomers learn three key numbers: 1) the orbital periods of the moon and planet, 2) the size of their orbits relative to the star, and 3) the size of planet and moon relative to the star.

Plugging those numbers into Kepler's Third Law yields the density of the star and planet. Since density is mass divided by volume, the relative densities and relative sizes gives the relative masses. Finally, scientists measure the star's wobble due to the planet's gravitational tug, known as the radial velocity. Combining the measured velocity with the relative masses, they can calculate the mass of the star directly.

"If there was no moon, this whole exercise would be impossible," stated Kipping. "No moon means we can't work out the exact density of the planet, so the whole thing grinds to a halt."

Kipping hasn't put his method into practice yet, since no star is known to have both a planet and moon that transit. However, NASA's Kepler spacecraft should discover several such systems.

"When they're found, we'll be ready to weigh them," said Kipping.

spacedaily.com

TalkingFields Guides European Farmers From Space

Sustainable food production and food security are critical challenges. An initiative of ESA's Integrated Application Promotion programme, TalkingFields will help by using space-based precision farming methods to produce crops more efficiently. For instance, by optimising farmers' use of fertiliser and giving early warning of plant disease risks not just on a field-by-field basis but within individual fields, both costs and environmental impacts can be reduced. Credits: TalkingFields

by Staff Writers
Paris, France (ESA) Oct 19, 2010
Farmers traditionally keep a close eye on their fields, but a new ESA-led project seeks to build on their vigilance with monitoring from space.

The TalkingFields initiative is now showing how to combine satellite observation with satellite navigation to benefit European farmers.

Sustainable food production and food security are critical challenges. TalkingFields will help by using precision farming methods to produce crops more efficiently. For instance, by optimising farmers' use of fertiliser and giving early warning of plant disease risks, both costs and environmental impacts can be reduced.

"There are existing services variously employing Earth observation data, satellite navigation, farm management software and crop growth models, but TalkingFields is the first to combine them all," said ESA's Tony Sephton.

"We're setting up an end-to-end service that is simple to use and sufficiently cost-effective to be self-sustaining."

How does it work? The farmer requests the service for an area defined using satnav. Satellites gather information on the land's potential - observations over several years can reveal variations in crop growth through soil changes - as well as current crop status.

These results are combined with information from field sensors such as weather conditions and soil moisture. The farmer adds in his own knowledge, and in return receives detailed satnav instructions on where and how much fertiliser to spray, for example.

A variety of satellites can be employed, although priority will be given to free data sources such as Landsat and ESA's forthcoming Sentinel-2 satellites, due for launch in 2012.

"Ideally, we might have weekly satellite acquisitions, but cloud cover makes that unfeasible," explained Dr Sephton.

"Instead, we need only two to four satellite images per growing season, which are fed into a sophisticated crop growth model.

"With TalkingFields the emphasis is on service: we're not giving raw satellite data straight to farmers. Instead, we advise them directly on actions to be taken throughout the growing season."

Following a 2009 feasibility study, TalkingFields is now being demonstrated in real fields, led for ESA by German Earth observation company VISTA with partners PC-Agrar, a German company specialising in providing farm management information software, and Ludwig Maximillians University Munich, which developed the hydrological and agricultural production model.

Farmers access TalkingFields via familiar farm management systems. "The quality of farming advice improves dramatically when all the available information is used," said Heike Bach of VISTA.

"Factors like crop variety, seeding date, row distance and fertilisation measures conducted so far are stored in the farm management system.

"Since TalkingFields is integrated with this software, we also have access to this information, improving our crop growth models."

Large intensive farms across Germany and Russia are participating in the demonstration. Customers can choose from a portfolio of services, such as estimating a crop's yield some two to four weeks before harvest.

Even before a farmer decides to use precision farming, he can obtain a detailed cost-benefit analysis for each field. Daily information on biomass and density will help to protect crops by revealing the onset of plant disease.

TalkingFields is being supported through the Integrated Applications Promotion (IAP) programme of ESA's Telecommunications and Integrated Applications Directorate.

IAP builds services for new groups of users by combining different space and terrestrial systems in novel ways.

www.spacedaily.com

NASA Awards Contracts For Innovative Lunar Demonstrations Data

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by Staff Writers
Washington DC (SPX) Oct 18, 2010
NASA has awarded Innovative Lunar Demonstrations Data (ILDD) contracts to six companies for the purchase of technical data resulting from industry efforts to develop vehicle capabilities and demonstrate end-to-end robotic lunar landing missions.

The data from these contracts will inform the development of future human and robotic lander vehicles and exploration systems.

The ILDD Broad Agency Announcement resulted in multiple award firm-fixed price indefinite-delivery/indefinite-quantity contracts with a total value of up to $301 million over a period of up to five years.

For each selected contractor, the minimum government purchase is $10,000, and the maximum government purchase is $10.01 million.

The contracts were awarded to:

Astrobotic Technology Inc., Pittsburgh, Pa.
The Charles Stark Draper Laboratory, Inc., Cambridge, Mass.
Dynetics Inc., Huntsville, Ala.
Earthrise Space Inc., Orlando, Fla.
Moon Express Inc., San Francisco Team FREDNET,
The Open Space Society, Inc., Huntsville, Ala.

The ILDD contracts provide for issuance of delivery orders that will specify data associated with system testing and integration, launch, in-space maneuvers, braking burns, lunar landing and other enhanced capabilities.

Knowledge acquired from this data will be applied to the development of lander systems necessary to execute human and robotic missions to the moon, near-Earth asteroids or other solar system destinations.

They will contribute to NASA's efforts to enable affordable and sustainable space exploration.

Awarded contracts will be managed by the Lunar Lander Project Office at NASA's Johnson Space Center in Houston.

www.space-travel.com

Doubt Cast On Existence Of Habitable Alien World

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by Leslie Mullen
Moffett Field CA (SPX) Oct 14, 2010
Last month, astronomers announced the discovery of the first potentially habitable extrasolar planet. But this week at an International Astronomical Union meeting, doubts were raised about the existence of this exciting new planet said to be orbiting the star Gliese 581.

Called 'Gliese 581 g,' the planet was determined to be about 3 times the mass of Earth, meaning it was a rocky world, not a gas giant like Jupiter. Rocky extrasolar planets have been found before, but the unique trait about this planet was that it orbited within the red dwarf star's habitable zone, that region of space where temperatures are sufficient for water to remain as a liquid on a planetary surface.

Astrobiologists were thrilled at the news, since liquid water is considered necessary for the origin and evolution of life. In fact, NASA has made it a primary aim to 'follow the water' in the search for life elsewhere in the galaxy.

The star Gliese 581 is 20 light years away from Earth, located in the constellation Libra.

"The fact that we were able to detect this planet so quickly and so nearby tells us that planets like this must be really common," said Steven Vogt in a press release announcing the discovery.

Vogt is one of the lead astronomers of the Lick-Carnegie Exoplanet Survey, and lead author on the paper published in the Astrophysical Journal (and posted online at the arxiv.org web site.) The paper also announced the discovery of planet 'f', a 7-Earth mass planet with a 433-day orbit around Gliese 581. Planet 'g' was calculated to have an orbital period of only 37 days. Although an extremely close orbit by the standards of our own solar system, because Gliese 581 is not as luminous as our sun its habitable zone must be much closer in.

Because the planet orbits so close to its star, astronomers said it must be tidally locked, with the same side of the planet always facing the star. This would mean that the star-side of the planet would be much hotter than the perpetually dark side, but a more temperate region could exist in the border zone between the dark and light sides.

To find the planet, the Lick-Carnegie team looked at 122 radial velocity measurements from the HIRES instrument on the Keck I telescope at the W.M. Keck Observatory in Hawaii. They also used 119 measurements from the HARPS instrument on the La Silla telescope at the European Southern Observatory in Chile.

The HIRES measurements were taken over a period of 11 years, while the HARPS measurements were made over 4 years.

Planet's Existence Not Confirmed

Francesco Pepe, an astronomer who works on HARPS data at the Geneva Observatory, said at the IAU meeting this week that his team could not confirm the existence of Gliese 581 g. In email correspondence with Astrobiology Magazine, Pepe said that they could not confirm the existence of planet 'f' either.

The Geneva team, led by Michel Mayor, announced in 2009 the discovery of planet 'e' in the Gliese 581 solar system. At approximately 1.9 Earth masses, this 'e' planet is the lowest mass extrasolar planet yet found, and has a 3.15-day orbital period around the star. "Since Mayor's announcement in 2009 of the lowest-mass planet Gliese 581 e, we have gathered about 60 additional data points with the HARPS instrument for a total of 180 data points spanning 6.5 years of observations," said Pepe. "From these data, we easily recover the 4 previously announced planets b, c, d, and e."

However, he said they do not see any evidence for planet 'g', the fifth planet in the system as announced by Vogt and his team.

"The reason for that is that, despite the extreme accuracy of the instrument and the many data points, the signal amplitude of this potential fifth planet is very low and basically at the level of the measurement noise," said Pepe.

The planets in the Gliese 581 system were discovered using spectroscopic radial velocity measurements. Planets 'tug' on the star they orbit, causing it to shift in position (stars and planets actually orbit a common center of mass). By measuring the star's movement in the sky, astronomers can figure out what sort of planets are orbiting it.

Multi-planet systems create a complicated signal, and astronomers must tease out the spectral lines to figure out what represents a planet, and what is just "noise" - shifts in the star light not caused by an orbiting planet. Astronomers have developed various ways to reduce such noise in their telescopic observations, but it still creates a level of uncertainty in detecting extrasolar planets.

The Geneva team plugged the HARPS data on Gliese 581 into computer models to check on the odds the signal was the result of noise, rather than evidence of the habitable planet 'g' as claimed by the Lick-Carnegie team.

"Simulations on the real data have shown that the probability that such a signal is just produced 'by chance' out of the noise is not negligible, of the order of several percents," Pepe said. "Under these conditions we cannot confirm the presence of the announced planet Gliese 581 g."

Pepe noted that while he did not speak at the IAU meeting about Gliese 581 f, the other potential planet in this system announced by the Lick-Carnegie team, the HARPS data calls that planet into question as well.

"We haven't made a detailed analysis yet, but at first glance no statistically significant signal [for planet f] is emerging from our data set," he said.

Gliese 581 is already one of the most intriguing solar systems known, with four planets confirmed orbiting the star. The addition of the potentially habitable planet 'g' would make the system the go-to place in the search for alien life, but more work needs to be done to either confirm or refute the planet's existence.

"I would say the detection was less than comfortably secure, even in the original Vogt et al. paper - the paper was carefully worded, as opposed to what was in some media reports," said Ray Jayawardhana, a University of Toronto astronomer who was not involved in either study. "Of course, it's not easy to definitively rule out something, but the HARPS evidence is at least raising some doubts."

www.spacedaily.com

Sciencespace Hotel Project To Be Launched After Contract Is Signed - Energia

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by Staff Writers
Moscow (RIA Novosti) Oct 13, 2010
The implementation of the project to build the first space hotel will only start after a contract between Russian state-owned rocket and space corporation Energia and Moscow-based company Orbital Technologies is signed, the Energia head said.

Orbital Technologies on Wednesday announced sky-high plans to launch an orbiting hotel in space by 2015-2016.

"As of now, the company only has an agreement of intent. When we have a firm contract, there will be the terms and engineering design," Vitaly Lopota said.

The project will cost hundreds of millions of dollars, Orbital Tehcnologies' CEO Sergei Kostenko said in late September, adding that Russian and U.S. investors have already been found.

Individuals, professional crews and explorers interested in implementing their own research programs are expected to be the first clients of the commercial tourist hub, Kostenko said then.

So far, several super-rich businesspeople have been the only space tourists, traveling into space with professional cosmonauts, but if the project is implemented the space tourism market is likely to develop rapidly.

www.space-travel.com

Habitable Martian Environments Could Be Deep Beneath Planet's Surface

The Holy Grail

by Staff Writers

Tucson AZ (SPX) Oct 12, 2010

A new discovery of hydrothermally altered carbonate-bearing rocks on Mars points toward habitable environments deep in the Martian crust, a PlanetaryScience Instituteresearcher said.

A deposit of carbonate rocks that once existed 6 km (about 4 miles) below the surface of Mars was uplifted and exposed by an ancient meteor impact, said Joseph Michalski, research scientist with PSI. The carbonate minerals exist along with hydrated silicate minerals of a likely hydrothermal origin.

Using data returned from NASA's Mars Reconnaissance Orbiter (MRO) spacecraft, researchers have spotted this unique mineralogy within the central peak of a crater to the southwest of a giant Martian volcanic province named Syrtis Major.

With infrared spectra from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), planetary geologists detected the hydrothermal minerals from their spectroscopic fingerprints.

Visible images from the High Resolution Imaging Science Experiment (HiRISE) camera aboard MRO show that the carbonates and hydrated silicate minerals occur within deformed bedrock that was exhumed by an ancient meteor impact that poked through the volcanic upper crust of Mars.

"Carbonate rocks have long been a Holy Grail of Mars exploration for several reasons," Michalski said.

"One reason is because carbonates form with the ocean and within lakes on Earth, so the same could be true for ancient Mars - such deposits could indicate past seas that were once present on Mars.

"Another reason is because we suspect that the ancient Martian atmosphere was probably denser and CO2-rich, but today the atmosphere is quite thin so we infer that the CO2 must have gone into carbonate rocks somewhere on Mars."

Michalski and co-author Paul B. Niles of NASA Johnson Space Center recently published the results in a paper titled "Deep crustal carbonate rocks exposed by meteor impact on Mars" in Nature Geoscience.

While this is not the first detection of carbonates on Mars, Michalski said, "This detection is significant because it shows other carbonates detected by previous workers, which were found in a fairly limited spatial extent, were not a localized phenomenon.

Carbonates may have formed over a very large region of ancient Mars, but been covered up by volcanic flows later in the history of the planet. A very exciting history of water on Mars may be simply covered up by younger lava!"

The discovery also has implications for the habitability of the Martian crust.

"The presence of carbonates along with hydrothermal silicate minerals indicates that a hydrothermal system existed in the presence of CO2 deep in the Martian crust," Michalski says.

"Such an environment is chemically similar to the type of hydrothermal systems that exist within the ocean floor of Earth, which are capable of sustaining vast communities of organisms that have never seen the light of day.

"The cold, dry surface of Mars is a tough place to survive, even for microbes. If we can identify places where habitable environments once existed at depth, protected from the harsh surface environment, it is a big step forward for astrobiological exploration of the red planet."

marsdaily.com

Opportunity Hits The Road Again

File image.

by Staff Writers
Pasadena CA (SPX) Oct 11, 2010
After spending time investigating a meteorite, Opportunity has resumed the trek to Endeavour crater with drives totaling over 370 meters (1,214 feet) for the past week.

On Sol 2377 (Oct. 1, 2010), the rover drove over 100 meters (328 feet), making a "bank shot" maneuver to avoid some troubling terrain. On Sol 2379 (Oct. 3, 2010), the rover performed a test of autonomous navigation using only the rear hazardous avoidance cameras (Hazcams).

The test was successful with the rover completing just about of 92 meters (302 feet) for the day. This new autonomous driving technique may enable longer, backward drives each sol.

On Sol 2381 (Oct. 5, 2010), Opportunity headed northeast to rejoin the original path to Endeavour crater, covering about 86 meters (282 feet). The rover drove again on the next sol moving another 93 meters (305 feet) along its way to Endeavour.

As of Sol 2382 (Oct. 6, 2010), solar array energy production was 610 watt-hours with an atmospheric opacity (Tau) of 0.538 and a solar array dust factor of 0.716.

Total odometry is 23,897.09 meters (23.90 kilometers, or 14.85 miles).

www.marsdaily.com

Hubble Uncovers An Overheated Early Universe

This diagram traces the evolution of the universe from the big bang to the present. Two watershed epochs are shown. Not long after the big bang, light from the first stars burned off a fog of cold hydrogen in a process called reionization. At a later epoch quasars, the black-hole-powered cores of active galaxies, pumped out enough ultraviolet light to reionize the primordial helium. Credit: NASA, ESA, and A. Feild (STScI). For a larger version of this image please go here.

by Staff Writers
Boston MA (SPX) Oct 08, 2010
If you think global warming is bad, 11 billion years ago the entire universe underwent, well, universal warming. The consequence was that fierce blasts of radiation from voracious black holes stunted the growth of some small galaxies for a stretch of 500 million years.

This is the conclusion of a team of astronomers who used the new capabilities of NASA's Hubble Space Telescope to probe the invisible, remote universe.

Using the newly installed Cosmic Origins Spectrograph (COS) they have identified an era, from 11.7 to 11.3 billion years ago, when the universe stripped electrons off from primeval helium atoms - a process called ionization.

This process heated intergalactic gas and inhibited it from gravitationally collapsing to form new generations of stars in some small galaxies. The lowest-mass galaxies were not even able to hold onto their gas, and it escaped back into intergalactic space.

Michael Shull of the University of Colorado and his team were able to find the telltale helium spectral absorption lines in the ultraviolet light from a quasar - the brilliant core of an active galaxy.

The quasar beacon shines light through intervening clouds of otherwise invisible gas, like a headlight shining through a fog. The beam allows for a core-sample probe of the clouds of gas interspersed between galaxies in the early universe.

The universe went through an initial heat wave over 13 billion years ago when energy from early massive stars ionized cold interstellar hydrogen from the big bang. This epoch is actually called reionization because the hydrogen nuclei were originally in an ionized state shortly after the big bang.

But Hubble found that it would take another 2 billion years before the universe produced sources of ultraviolet radiation with enough energy to do the heavy lifting and reionize the primordial helium that was also cooked up in the big bang.

This radiation didn't come from stars, but rather from quasars. In fact the epoch when the helium was being reionized corresponds to a transitory time in the universe's history when quasars were most abundant.

The universe was a rambunctious place back then. Galaxies frequently collided, and this engorged supermassive black holes in the cores of galaxies with infalling gas. The black holes furiously converted some of the gravitational energy of this mass to powerful far-ultraviolet radiation that would blaze out of galaxies.

This heated the intergalactic helium from 18,000 degrees Fahrenheit to nearly 40,000 degrees. After the helium was reionized in the universe, intergalactic gas again cooled down and dwarf galaxies could resume normal assembly. "I imagine quite a few more dwarf galaxies may have formed if helium reionization had not taken place," said Shull.

So far Shull and his team only have one sightline to measure the helium transition, but the COS science team plans to use Hubble to look in other directions to see if the helium reionization uniformly took place across the universe.

www.spacedaily.com

Living Fossils Debunk Star-Formation Route

A simulation of a star-forming galaxy similar to those observed. Cold gas (red) flowing onto a spiral galaxy feeds star formation. This intense star formation drives turbulent outflows (blue). Credit: Robert Crain, James Geach, the Virgo Consortium, Andy Green and

by Staff Writers

Work based on data from the Australian Astronomical Observatory has discounted one route for forming stars. The work is this week's cover story in the journal Nature.

In their paper ("High star formation rates as the origin of turbulence in early and modern disk galaxies"), Swinburne University astronomy student Andy Green, Green's supervisor and team leader Professor Karl Glazebrook, and their colleagues report finding galaxies in today's Universe that were thought to exist only in the distant past.

"They're living fossils of space - galaxies we just didn't expect to find in today's world," said Green.

The galaxies in question are like our own Galaxy in shape, but unlike our Galaxy they are physically turbulent and are forming lots of stars. Astronomers see many of them in the distant, early Universe, but they are rare now, and this team is the first to find any in today's Universe.

The finding knocks on the head one way astronomers thought stars might form.

Stars form from gas, and to form rapidly they need a good supply of it. Astronomers had thought that star formation in distant, early galaxies might be fuelled by cold streams of gas continually falling into those galaxies. But this mechanism could only work when the Universe was young. Finding these modern galaxies frenziedly forming new stars calls this idea into question.

Instead it seems more likely that galaxies get their new gas through 'mergers and acquisitions' - merging with like-sized counterparts or swallowing smaller galaxies.

To find the very rare, turbulent galaxies, Green's team had to observe many galaxies, over a large volume of sky. They started by selecting galaxies from the Sloan Digital Sky Survey that showed a key indicator of star formation: a bright H-alpha spectral line emitted by hydrogen gas.

Green then observed these chosen galaxies with the 3.9-meter Anglo-Australian Telescope (AAT), operated by the Australian Astronomical Observatory, and the 2.3-meter telescope of the Australian National University, both located at Siding Spring Observatory in eastern Australia. About two-thirds of the data came from the AAT.

Australian Astronomical Observatory Director, Professor Matthew Colless, was a member of the research team. He says the study shows the value of the Australian telescopes for complementing observations of the very distant Universe.

"Our telescopes are ideal for detailed study of the nearby counterparts of galaxies seen in the distant universe by the eight- and ten-meter telescopes," he said. "That's essential for piecing together the history of the Universe, from ancient times down to the present."

spacedaily.com

Soyuz Moved To Pad For Thursday Launch To Station

Launch scaffolding is raised into place around the Soyuz rocket shortly after arrival to the launch pad Tuesday at the Baikonur Cosmodrome in Kazakhstan. Credit: NASA/Carla Cioffi Russia holds 1st place on space launch market MOSCOW, Oct. 5 (Xinhua) Russia held the first place in terms of space launches, according to the report of the Russian space agency, Roskosmos, published by RIA Novosti news agency on Tuesday. Since the start of 2010, Russia made 22 launches. Of this number, 16 were made from Kazakhstan-located Baikonur site, five from Russian Plesetsk and one from a launching site of Dombarovskaya missile division, Roskosmos' report said. These launches have been made for service of the Defense Ministry, GLONASS navigation system and federal space programs. For the same period, the United States made 11 launches, and China sent to space 10 rockets. This is the third year in a row that Russia occupies the first place on the space launches market. In 2009, the frequency of Russian flights to the International Space Station rose twofold compared with that in 2008.

by Staff Writers
Baikonur, Kazakhstan (SPX) Oct 06, 2010
The Soyuz spacecraft that will carry three new Expedition 25 flight engineers to the International Space Station was rolled out to the launch pad at the Baikonur Cosmodrome in Kazakhstan on Tuesday.

NASA astronaut Scott Kelly and Russian cosmonauts Alexander Kaleri and Oleg Skripochka will launch aboard the new Soyuz TMA-01M Thursday at 7:10 p.m. EDT (Friday, Kazakhstan time) and begin a five-month tour of duty aboard the station after docking to the Poisk module Saturday evening.

Meanwhile, the three Expedition 25 crew members already living and working aboard the station conducted a depressurization drill, collected data for science research and prepared for the installation of a device to produce water.

Commander Doug Wheelock began his workday early by participating in the Pro K experiment, which studies dietary countermeasures to lessen the bone loss experienced by astronauts during long-duration spaceflight.

With assistance from Flight Engineer Shannon Walker, Wheelock collected a blood sample and stored it in the Minus Eighty-Degree Laboratory Freezer for ISS for study later by scientists back on Earth.

Walker spent much of her morning with the Capillary Flow Experiment for an investigation of capillary flows and flows of fluids in containers with complex geometries.

Results of this study will improve current computer models used by designers of low-gravity fluid systems and may improve fluid transfer systems on future spacecraft.

Flight Engineer Fyodor Yurchikhin continued unpacking cargo from the ISS Progress 39 spacecraft that has been docked to the aft port of the Zvezda service module since September

Later Yurchikhin joined Wheelock and Walker for an emergency drill to sharpen the crew's response to a rapid, unexpected loss of cabin pressure within the station. Afterward the three tagged up with flight controllers for a debrief of the drill.

After a break for lunch, Wheelock used a ham radio to speak with students at the Institute of Research and Education in Italy and answered a variety of questions about life aboard the space station.

Wheelock then tagged up with flight controllers to discuss the upcoming installation of the Sabatier, which combines carbon dioxide from the Carbon Dioxide Removal Assembly and hydrogen from the Oxygen Generation System to form water and methane.

The water will be recycled by the Water Processor Assembly, and the methane vented overboard.

www.space-travel.com

Cluster Helps Disentangle Turbulence In The Solar Wind

An artist's impression of the Cluster quartet. Credit: ESA.

by Karen C. Fox

Washington DC (SPX) Oct 05, 2010

From Earth, the Sun looks like a calm, placid body that does little more than shine brightly while marching across the sky. Images from a bit closer, of course, show it's an unruly ball of hot gas that can expel long plumes out into space - but even this isn't the whole story.

Surrounding the Sun is a roiling wind of electrons and protons that shows constant turbulence at every size scale: long streaming jets, smaller whirling eddies, and evenmicroscopic movements as charged particles circle in miniature orbits. Through it all, great magnetic waves and electric currents move through, stirring up the particles even more.

This solar wind is some million degrees Celsius, can move as fast as 750 kilometers (466 statute miles) per second, and - so far - defies a complete description by any one theory. It's hotter than expected, for one, and no one has yet agreed which of several theories offers the best explanation.

Now, the ESA/NASA Cluster mission - four identical spacecraft that fly in a tight formation to provide 3-dimensional snapshots of structures around Earth - has provided new information about how the protons in the solar wind are heated.

"We had a perfect window of 50 minutes," says NASA scientist Melvyn Goldstein, chief of the Geospace Physics Laboratory at NASA's Goddard Space Flight Center in Greenbelt, Md. and co-author of the new paper that appeared in Physical Review Letters on September 24.

"It was a time when the four Cluster spacecraft were so close together they could watch movements in the solar wind at a scale small enough that it was possible to observe the heating of protons through turbulence directly for the first time."

Scientists know that large turbulence tends to "cascade" down into smaller turbulence - imagine the sharply defined whitecaps on top of long ocean waves.

In ocean waves, the energy from such cascades naturally adds a small amount of heat from friction as the particles shift past each other, thus heating the water slightly. But the fast, charged particles - known as "plasma" - around the sun don't experience that kind of friction, yet they heat up in a similar way.

"Unlike the usual fluids of everyday life," says Fouad Sahraoui, lead author of a new paper on the solar wind and a scientist at the CNRS-Ecole Polytechnique-UPMC in France, "plasmas possess electric and magnetic fields generated by the motions of proton and electrons. This changes much of the intuitive images that we get from observing conventional fluids."

Somehow the magnetic and electric fields in the plasma must contribute to heating the particles. Decades of research on the solar wind have been able to infer the length and effects of the magnetic waves, but direct observation was not possible before the Cluster mission watched large waves from afar.

These start long as long wavelength fluctuations, but lose energy - while getting shorter - over time. Loss of energy in the waves transfer energy to the solar wind particles, heating them up, but the exact method of energy transfer, and the exact nature of the waves doing the heating, has not been completely established.

In addition to trying to find the mechanism that heats the solar wind, there's another mystery: The magnetic waves transfer heat to the particles at different rates depending on their wavelength. The largest waves lose energy at a continuous rate until they make it down to about 100-kilometer wavelength.

They then lose energy even more quickly before they hit around 2-kilometer wavelength and return to more or less the previous rate. To tackle these puzzles, scientists used data from Cluster when it was in the solar wind in a position where it could not be influenced by Earth's magnetosphere.

For this latest paper, the four Cluster spacecraft provided 50 minutes of data at a time when conditions were just right - the spacecraft were in a homogeneous area of the solar wind, they were close together, and they formed a perfect tetrahedral shape - such that the instruments could measure electromagnetic waves in three dimensions at the small scales that affect protons.

The measurements showed that the cascade of turbulence occurs through the action of a special kind of traveling waves - named Alfven waves after Nobel laureate Hannes Alfven, who discovered them in 1941.

The surprising thing about the waves that Cluster observed is that they pointed perpendicular to the magnetic field. This is in contrast to previous work from the Helios spacecraft, which in the 1970's examined magnetic waves closer to the sun.

That work found magnetic waves running parallel to the magnetic field, which can send particles moving in tight circular orbits - a process known as cyclotron resonance - thus giving them a kick in both energy and temperature. The perpendicular waves found here, on the other hand, create electric fields that efficiently transfer energy to particles by, essentially, pushing them to move faster.

Indeed, earlier Cluster work suggested that this process - known as Landau damping - helped heat electrons. But, since much of the change in temperature with distance from the sun is due to changes in the proton temperature, it was crucial to understand how they obtained their energy. Since hot electrons do not heat protons very well at all, this couldn't be the mechanism.

That Landau damping is what adds energy to both protons and electrons - at least near Earth - also helps explain the odd rate change in wave fluctuations as well. When the wavelengths are about 100 kilometers or a bit shorter, the electric fields of these perpendicular waves heat protons very efficiently.

So, at these lengths, the waves transfer energy quickly to the surrounding protons - offering an explanation why the magnetic waves suddenly begin to lose energy at a faster rate.

Waves that are about two kilometers, however, do not interact efficiently with protons because the electric fields oscillate too fast to push them. Instead these shorter waves begin to push and heat electrons efficiently and quickly deplete all the energy in the waves.

"We can see that not all the energy is dissipated by protons," Sahraoui said. "The remaining energy in the wave continues its journey toward smaller scales, wavelengths of about two kilometers long. At that point, electrons in turn get heated."

Future NASA missions such as the Magnetospheric Multiscale mission, scheduled for launch in 2014, will be able to probe the movements of the solar wind at even smaller scales.

Cluster recently surpassed a decade of passing in and out of our planet's magnetic field, returning invaluable data to scientists worldwide. Besides studying the solar wind, Cluster's other observations include studying the composition of the earth's aurora and its magnetosphere.

spacedaily.com

Milky Way Sidelined In Galactic Tug Of War

This plot shows the simulated gas distribution of the Magellanic System resulting from the tidal encounter between the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) as they orbit our home Milky Way Galaxy. The entire sky is plotted in galactocentric coordinates of longitude and latitude. The Magellanic Stream is the pronounced tail of material that stretches 150 degrees across the southern sky. The solid line shows the calculated path of the LMC and the dotted line is the path of the SMC. The color range from dark to light shows the density (lower to higher) of the hydrogen gas making up the Magellanic Stream and the Bridge that connects the two dwarf galaxies. Credit: Plot by G. Besla, Milky Way background image by Axel Mellinger

by Staff Writers

The Magellanic Stream is an arc of hydrogen gas spanning more than 100 degrees of the sky as it trails behind the Milky Way's neighbor galaxies, the Large and Small Magellanic Clouds. Our home galaxy, the Milky Way, has long been thought to be the dominant gravitational force in forming the Stream by pulling gas from the Clouds.

A new computer simulation by Gurtina Besla (Harvard-Smithsonian Center for Astrophysics) and her colleagues now shows, however, that the Magellanic Stream resulted from a past close encounter between these dwarf galaxies rather than effects of the Milky Way.

"The traditional models required the Magellanic Clouds to complete an orbit about the Milky Way in less than 2 billion years in order for the Stream to form," says Besla. Other work by Besla and her colleagues, and measurements from the Hubble Space Telescope by colleague Nitya Kallivaylil, rule out such an orbit, however, suggesting the Magellanic Clouds are new arrivals and not long-time satellites of the Milky Way.

This creates a problem: How can the Stream have formed without a complete orbit about the Milky Way?

To address this, Besla and her team set up a simulation assuming the Clouds were a stable binary system on their first passage about the Milky Way in order to show how the Stream could form without relying on a close encounter with the Milky Way.

The team postulated that the Magellanic Stream and Bridge are similar to bridge and tail structures seen in other interacting galaxies and, importantly, formed before the Clouds were captured by the Milky Way.

"While the Clouds didn't actually collide," says Besla, "they came close enough that the Large Cloud pulled large amounts of hydrogen gas away from the Small Cloud. This tidal interaction gave rise to the Bridge we see between the Clouds, as well as the Stream."

"We believe our model illustrates that dwarf-dwarf galaxy tidal interactions are a powerful mechanism to change the shape of dwarf galaxies without the need for repeated interactions with a massive host galaxy like the Milky Way."

While the Milky Way may not have drawn the Stream material out of the Clouds, the Milky Way's gravity now shapes the orbit of the Clouds and thereby controls the appearance of the tail.

"We can tell this from the line-of-sight velocities and spatial location of the tail observed in the Stream today," says team member Lars Hernquist of the Center.

spacedaily.com