NASA is getting ready to launch a new mission, a mission to observe a largely unexplored region of the solar atmosphere that powers its dynamic million-degree outer atmosphere and drives the solar wind.

In late June 2013, the Interface Region Imaging Spectrograph, or IRIS, will launch from Vandenberg Air Force Base, Calif. IRIS will advance our understanding of the interface region, a region in the lower atmosphere of the sun where most of the sun's ultraviolet emissions are generated. Such emissions impact the near-Earth space environment and Earth's climate.

The interface region lies between the sun's 11,000-degree Fahrenheit, white-hot, visible surface, the photosphere, and the much hotter multi-million-degree upper corona. Interactions between the violently moving plasma and the sun's magnetic field in this area may be the source of the energy that heats the corona to some hundreds and occasionally thousands of times hotter than the sun's surface.

IRIS will orbit Earth and use its ultraviolet telescope to obtain high-resolution solar images and spectra. IRIS observations along with advanced computer models will deepen our understanding of how heat and energy move through the lower atmosphere of the sun and other sun-like stars.

For more information about NASA's IRIS mission, please visit: http://www.nasa.gov/iris

NASA's Asteroid Sample Return Mission Moves into Development

NASA's first mission to sample an asteroid is moving ahead into development and testing in preparation for its launch in 2016.

The Origins-Spectral Interpretation Resource Identification Security Regolith Explorer (OSIRIS-REx) passed a confirmation review Wednesday called Key Decision Point (KDP)-C. NASA officials reviewed a series of detailed project assessments and authorized the spacecraft's continuation into the development phase.

OSIRIS-REx will rendezvous with the asteroid Bennu in 2018 and return a sample of it to Earth in 2023.

"Successfully passing KDP-C is a major milestone for the project," said Mike Donnelly, OSIRIS-REx project manager at NASA's Goddard Space Flight Center in Greenbelt, Md. "This means NASA believes we have an executable plan to return a sample from Bennu. It now falls on the project and its development team members to execute that plan."

Bennu could hold clues to the origin of the solar system. OSIRIS-REx will map the asteroid's global properties, measure non-gravitational forces and provide observations that can be compared with data obtained by telescope observations from Earth. OSIRIS-REx will collect a minimum of 2 ounces (60 grams) of surface material.

"The entire OSIRIS-REx team has worked very hard to get to this point," said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona in Tucson. "We have a long way to go before we arrive at Bennu, but I have every confidence when we do, we will have built a supremely capable system to return a sample of this primitive asteroid."

The mission will be a vital part of NASA's plans to find, study, capture and relocate an asteroid for exploration by astronauts. NASA recently announced an asteroid initiative proposing a strategy to leverage human and robotic activities for the first human mission to an asteroid while also accelerating efforts to improve detection and characterization of asteroids.

NASA's Goddard Space Flight Center in Greenbelt, Md., will provide overall mission management, systems engineering and safety and mission assurance. The University of Arizona in Tucson is the principal investigator institution. Lockheed Martin Space Systems of Denver will build the spacecraft. OSIRIS-REx is the third mission in NASA's New Frontiers Program. NASA's Marshall Space Flight Center in Huntsville, Ala., manages New Frontiers for NASA's Science Mission Directorate in Washington.

Impacts of Strong Solar Flares

Given a legitimate need to protect Earth from the most intense forms of space weather -- great bursts of electromagnetic energy and particles that can sometimes stream from the sun -- some people worry that a gigantic "killer solar flare" could hurl enough energy to destroy Earth, but this is not actually possible.

Solar activity is indeed currently ramping up toward what is known as solar maximum, something that occurs approximately every 11 years. However, this same solar cycle has occurred over millennia so anyone over the age of 11 has already lived through such a solar maximum with no harm.

This is not to say that space weather can't affect our planet. The explosive heat of a solar flare can't make it all the way to our globe, but electromagnetic radiation and energetic particles certainly can. Solar flares can temporarily alter the upper atmosphere creating disruptions with signal transmission from, say, a GPS satellite to Earth causing it to be off by many yards. Another phenomenon produced by the sun could be even more disruptive. Known as a coronal mass ejection or CME these solar explosions propel bursts of particles and electromagnetic fluctuations into Earth's atmosphere. Those fluctuations could induce electric fluctuations at ground level that could blow out transformers in power grids. A CME's particles can also collide with crucial electronics onboard a satellite and disrupt its systems.

In an increasingly technological world, where almost everyone relies on cellphones, and GPS controls not just your in-car map system, but also airplane navigation and the extremely accurate clocks that govern financial transactions, space weather is a serious matter.

But it is a problem the same way hurricanes are a problem. One can protect oneself with advance information and proper precautions. During a hurricane watch, a homeowner can stay put … or he can seal up the house, turn off the electronics and get out of the way. Similarly, scientists at NASA and NOAA give warnings to electric companies, spacecraft operators and airline pilots before a CME comes to Earth so that these groups can take proper precautions.

NOAA's Space Weather Prediction Center  is the U.S. government’s official source for space weather forecasts, alerts, watches and warnings. Improving these predictive abilities the same way weather prediction has improved over the last few decades is one of the reasons NASA studies the sun and space weather. We can't ignore space weather, but we can take appropriate measures to protect ourselves.

And, even at their worst, the sun's flares are not physically capable of destroying Earth.

NASA's First Minisatellite Mission Comes to Successful End

An artist's rendering of the FASTSAT minisatellite in Earth orbit. (NASA/MSFC)

After two successful years of on-orbit operations, NASA's Fast, Affordable, Science and Technology Satellite, or FASTSAT, mission is coming to an end. FASTSAT successfully demonstrated a capability to build, deploy and operate a science and technology flight mission at lower costs than previously possible. The satellite was designed, developed and tested over a period of 14 months at NASA's Marshall Space Flight Center in Huntsville, Ala., in partnership with the Von Braun Center for Science & Innovation and Dynetics, both of Huntsville, and the Department of Defense's Space Test Program.

Requiem for the World’s Greatest Planet Hunter

The 2,740 planets detected by Kepler as they passed in front of their stars are depicted here as black dots. View the image full size to appreciate the true avolume of data. (Credit: Kepler/NASA)

Kepler’s results show that about one in six stars has one or more Earth-sized planets in a fast orbit. That translates to at least 17 billion such planets in our galaxy, and many more planets in slower, Earth-like orbits. Credit: F. Fressin (CfA)

A bewildering variety of planets have been found by the Kepler spacecraft. This illustration is based on best guesses about what those planets are like. Further study almost guarantees more surprises. (Credit: C. Pulliam & D. Aguilar/CfA)

After more than four years in space, restlessly searching for planets orbiting other stars, NASA’s Kepler space telescope may have met its demise.
The Kepler project is typically described in terms of raw numbers. As of the last official announcement, it had found 2,740 likely new planets–including 1,200 Neptune-size planets, 350 Earth-size planets, and at least 4 planets that orbit within the “habitable zone” where liquid water can exist. All of those numbers are sure to increase, as more observations are confirmed and as mission scientists continue to dig through a trove of archived data. But spirit, not statistics, is what really defines Kepler. It is a modern version of the expedition of Lewis and Clark, or the great voyages of Vasco da Gama and Ferdinand Magellan. It is a headlong plunge into the unknown cosmic territory around us.
Extrapolating from Kepler’s results, astronomers now estimate there are at least 17 billion Earth-size planets in our galaxy. That is another number, yes, but one with a powerful message: Another age of exploration awaits, one that may very well lead to the discovery that humanity is not alone in the universe. 
There could hardly be a sharper contrast between Kepler’s grandiose mission and the humble mechanical failure that threatens to end it. The fault lies in one of the telescope’s gyroscopic reaction wheels, a key component of its pointing system. Kepler needs three reaction wheels running at all times to maintain a stable position. Think of it like a stool: Two legs are just not enough to keep things balanced.
Extreme stability is essential because of the way that Kepler finds planets around other stars. It points a 0.95-meter (3-foot) light-collecting mirror toward the constellation Cygnus, watching approximately 150,000 stars and monitoring the tiny dimming that happens whenever a planet passes in front of one of them. And by tiny I mean tiny; Kepler seeks out brightness changes as slight as 0.01 percent. Since all the stars in Kepler’s field of view are quite close together in the sky, and since the shadows of passing planets are exceedingly subtle, there is little room for error.
Kepler started out with four functional reaction wheels, allowing for one to go bad without harming the mission. Last July, wheel #2 failed and was switched off. On May 12, wheel #4 apparently failed as well, leaving only two working wheels and sending Kepler into an automatic “safe” mode.
That is not necessarily the end of the line for the hardy telescope, which has been operating nonstop for 1,532 days. Scott Hubbard, former director of NASA’s Ames Research Center, notes that it might be possible to restart wheel #2 and see if it is now functional, which is possible if its lubrication shifted in the interim. Kepler has thruster rockets that could be used to stand in for the third reaction wheel, at least for a few months until the propellant runs out. NASA mission planners have also discussed trying to run wheel #4 backward or otherwise getting it somewhat operational again.
So a requiem for Kepler is somewhat premature. It is also not the right tone. If this is the end of the mission, there is far more to celebrate than there is to mourn. The Kepler team just posted an upbeat assessment of what comes next: “Even if data collection were to end, the mission has substantial quantities of data on the ground yet to be fully analyzed, and the string of scientific discoveries is expected to continue for years to come.” William Borucki, the principal investigator for Kepler, is optimistic that more Earth-like planets lurk within that trove.
Last week, an international team used Kepler data to identify a new planet, nicknamed “Einstein’s planet,” using a novel technique based on the effects of relativity. Multiple ground-based efforts will carry on the search for planets around other stars, and NASA recently approved a successor mission, TESS, that will specifically seek nearby Earthlike worlds.
This is also a good time to recall how extraordinary it is that the Kepler mission happened at all. Last year Borucki gave an in-depth interview with Andrew Grant, an associate editor at DISCOVER, describing the hurdles that he and his collaborators overcame to make the mission happen–a process that at times seemed more Sisyphean than Herculean.
In the 1970s, when Borucki began thinking about searching for extrasolar planets, nobody knew if such planets even existed. In the 1980s, when Borucki began sketching out the starlight-dimming search technique that Kepler uses, most of his colleagues scoffed. “The reviewers quickly rejected it,” he recalls. “They said there were no detectors that could make such precise measurements.”
I clearly remember the mood at that time, because I too was obsessed with the idea of planets around other stars back when it was more science fiction than fact. In the 1950s an 1960s, Dutch astronomer Peter van de Kamp reported evidence of planets around Barnard’s Star and 61 Cygni–but these claims were later debunked. In his book The Cosmic Connection, Carl Sagan showcased some elegant simulations of what other planetary systems might look like–but these were only theoretical models.
For years, Canadian astronomer Bruce Campbell championed the idea of watching the back-and-forth motions of stars to search for the gravitational pull of unseen planets. That technique eventually turned out to be spectacularly successful, but it required a level of precision beyond what Campbell could attain.
Campbell is a forgotten hero in the quest to find to find new worlds beyond our solar system. His pioneering work made possible the series of spectacular planetary finds that began with the discovery of a searing-hot, Jupiter-size planet around 51 Pegasi in 1995. Seven years before that, Campbell (along with Gordon Walker and Stephenson Yang) published a paper presenting evidence for a planet around the star Gamma Cephei. He admitted that the detection was tentative, since it was right at the limits of what his equipment could do.
The report received little attention, and Campbell’s name is missing from most stories about the discovery of exoplanets. He barely registers in a Google search (even after you weed out the other Bruce Campbell, the one who stars in Burn Notice). But the Gamma Cephei planet was eventually confirmed, and the 1988 paper by Campbell, Walker, and Stephenson is the very first verified detection of a planet around another star.
Whether or not this is the end of the Kepler spacecraft, Kepler’s mission–and the mission of Campbell, Borucki, and the many many others who made it possible–goes on. The next great moment in the age of planetary discovery lies just ahead.-NASA

How to build a Mars colony that lasts – forever

"Mars can't just be a one-shot mission," says Apollo 11 astronaut Edwin "Buzz" Aldrin, the second person to walk on the moon.

He's part of a group who met last week in Washington DC for the first Human to Mars Summit, or H2M. The astronauts, researchers and space flight firms aim to chart a path to the Red Planet by 2030.

And they are thinking beyond mere visits. Though it won't be easy, they say establishing a permanent, sustainable outpost on the Red Planet may be our civilisation's only chance of long-term continuity.

"Single-planet species don't survive," says former astronaut John Grunsfeld, who still works at NASA. "That's a pretty sound theorem – just look at the dinosaurs. But we don't want to prove it."

Modular base

As the only other planet in the solar system we are likely to be able to settle on, Mars looks like the best first step towards establishing an off-Earth foothold. But making Mars a sustainable destination will require a few advances beyond those needed for one-off trips.

For a start, humans who plan on seeding a colony will need bigger living quarters – both to accommodate life-support systems and supplies, and to minimise psychological trouble, said David Dinges at the University of Pennsylvania in Philadelphia. He recently reported on the behaviours of participants in the mock Mars 500 project, in which six men spent 520 days in a 3.6-by-20-metre habitat on Earth.

Despite screenings, four had extensive problems with lethargy, insomnia and productivity, which Dinges attributes in part to their tight confinement. Just imagine how this would play out on much longer missions.

But building larger habitats will require a rethink in transport, as landing heavy loads on Mars is a huge challenge. The International Space Station, which was built in stages during a series of launches, provides some inspiration. The parts for a Martian base could be delivered similarly, by landing modules in a series of missions.

Phobos first

Then it could be built by a crew already on the surface, by robots in orbit or even by a crew based on a Martian moon. At H2M, Aldrin suggested sending three people to spend 18 months on Phobos, where they would remotely construct a base on Mars. Phobos has a nearly constant view of the Martian surface and is easier to land on than Mars because its lack of an atmosphere removes the need for technologies such as heavy heat shields and supersonic retro-rockets.

Assuming a large enough base can be built, the next challenge will be a sustainable food supply. Growing vegetables is an option, but plants may need to deal with higher radiation, low air pressure and reduced gravity. If Mars gardeners are to use Martian soil, a knowledge of how crops respond to its contents, such as sulphates and perchlorates will be required.

To get around any difficulties, genetically modified crops may come in useful, says Robert Ferl, director of the Interdisciplinary Center for Biotechnology Research at the University of Florida in Gainesville: "This is the era of understanding what happens to organisms at the genetic level."

We now know the patterns of gene expression behind how many plants on Earth assimilate key nutrients such as sulphates. This could eventually allow the right genes to be added to crops bound for Mars. Terrestrial plants growing in extreme places could also be adapted or mined for their hardier genes.

Printed noodles

For a less conventional meal, Anjan Contractor of Systems and Materials Research Corporation in Austin, Texas, has NASA funding to develop a 3D printer for hot food on deep-space missions. The food powders are UV sterilised, fortified with nutrients and have a shelf life of at least 15 years, says Contractor. His team has so far printed noodles, turkey loaf, basil paste, bread and cake – though they won't taste their creations until a new, food-only printer is used for the job.

There could be longer-term challenges to sustaining a colony, however. Richard Zurek, Mars chief scientist at NASA's Jet Propulsion Laboratory in Pasadena, California, fears a colony will only sustain itself if it can find a resource to trade with Earth. "But that seems unlikely unless the cost of transport between planets is greatly reduced," he says.

Still, high public interest and the emergence of private space flight suggest that the dream of reaching Mars is closer to becoming reality, says Aldrin. "By implementing a step-by-step vision for Mars, we'll plunge further outward into the solar system," he says

Why Mercury is a hard orange, not a soft peach

Object: Mercury-like planets
Composition: Large, iron-rich cores
Position in solar system: Closest to their stars

If our solar system's hellishly hot, innermost planet Mercury were an orange, its enormous, iron-rich core would be the juicy, fruity bit, leaving just the thin rind for the crust and mantle. This has puzzled astronomers for decades, as conventional planetary formation models cannot produce such a relatively large core. Earth and the other terrestrial planets, by contrast, have cores more like the pit of a peach – giving them a lower density overall.

Astronomers speculated that Mercury could have suffered a massive impact that stripped away a silicate mantle. Alternatively, its outer layers could have evaporated away from the heat of the sun. But in the last few years, NASA's Messenger probe has found volatile elements like potassium in the planet's crust. If it had suffered either the trauma of an impact or evaporation, those elements should not have survived and persisted – according to most models.

In the meantime, the mystery has only become more pressing. Recent observations of extrasolar planets suggest that Mercury's structure might not be unique: the two smallest exoplanets whose densities are known, Kepler-10b and Corot-7b, are also far denser than expected, suggesting they share Mercury's orange-like structure. And these planets, like Mercury, also sit close to their sun. Now, a new theory may explain the whole coterie in one fell swoop. The culprit? The heat provided by starlight.

Hot side

When gas molecules collide with a hot dust grain, they pick up heat, bouncing off faster than they approached. This gives the grain a little shove. Gerard Wurm of the University of Duisburg-Essen in Germany and colleagues calculated how this photophoretic force would affect dust grains swirling around a star.

Because metallic grains conduct heat, they are evenly heated throughout. As a result, they will be shoved from all sides and so will not move far from the star, the team found. Insulating grains, however, such as less-dense silicates, have a hot, sun-facing side, where departing gas molecules will give a bigger shove than those on the cold side.

Wurm's team says the effect of this over time will be to sort the grains in a nascent solar system, with metals left close to the star, and less dense particles pushed further out. Planets eventually form from these grains, so this process could explain why inner planets like Mercury, Kepler-10b and Corot-7b, are so dense.

"I think it all fits together logically," Wurm says. "You have metal-rich objects closer to the star, because you can't push them. The further you go out in a planetary system, the less metal you have to build planets."

The research will appear in The Astrophysical Journal.

Tower drop

Photophoresis is not a new idea. A century ago, physicists who worked with vacuum chambers worried about it constantly. "This was in every experiment because the [vacuum] pumps were so bad," says Wurm. The force is only significant in imperfect vacuum conditions, where there's a little bit of gas but not too much. As pumps improved, physicists began to leave photophoresis out of their calculations. "It kind of vanished for 100 years," says Wurm

.

some like it hot.

Larry Nittler of the Carnegie Instition of Washington likes the idea of linking photophoresis to the Mercury mystery, but he cautions that Wurm's team's theory on planet formation is not conclusive, and he stresses that the rival mantle-stripping explanation is not dead.

Future work could include carrying out computer simulations of our solar system that take photophoresis into account and comparing the predicted composition with measurements of Mercury taken by the Messenger probe, Nittler suggests.

Wurm is actually planning a cruder simulation – run in the real world, not on a computer. He hopes to drop a sealed capsule containing metals and dust from a 110-meter tower in Bremen, Germany, to simulate the weightlessness of space. He will zap the falling capsule with an infrared laser, and check whether the dust and metals start to separate as he predicts.

In the meantime, you could say it's oranges 1, peaches 0.