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Close Encounters of the Worrisome Kind? Chinese Satellites Meet in Space

September 1st, 2010 09:56 admin No comments

SpaceJunkFor two years, the Chinese science satellite SJ-06F flew solo orbits around the Earth (or, as solo as a machine could be in the expanding haze of space junk in orbit). But now it has a partner: Last month China executed the delicate maneuver of aligning another satellite launched this year, SJ-12, with its older counterpart.

Only the United States had executed such a satellite rendezvous before this, and it shows off China’s advancement in satellite sophistication. Three years ago the country blew one of its satellites to smithereens in a practice test—a test that created thousands of additional chunks of debris in orbit. The satellite meet-up is a more elegant trick, and one whose implications could be sinister or benign. Let’s explore both possibilities.

Don’t Worry

China’s game of catch-up, which has its space program closing in on America’s abilities in orbit, strikes fear into the hearts of some politicos. But malfeasance need not be the aim of the satellite maneuver.

“This set of skills serves a whole lot of purposes,” says Dean Cheng, a Chinese policy expert with the Heritage Foundation, a think tank in Washington DC. The most immediate application, Cheng says, may be testing sensors and control systems to help pave the way for docking procedures to be used with China’s first space station module, Tiangong-1, which is set to launch in 2011. “This sort of thing may very well be consistent with wanting to test drive the hardware and software before you test it on your space laboratory,” Cheng says. [New Scientist]

And speaking of space junk (as we were earlier), this kind of procedure could be used in the future to clear out the defunct equipment and debris that clogs the space around our planet and threatens useful machinery in orbit.

What of the worry that China could dock with our satellites and interfere with them? Brian Weeden of the Secure World Foundation, who I talked to for a story in the September issue of DISCOVER, tracked the rendezvous and says that’s unlikely. Weeden, whose organization is devoted to the peaceful use of space, says that there are easier ways to mess with enemy satellites, like shooting them with lasers from the ground.

OK, Worry

Whether or not China is pursuing space warfare in this instance, the country is certainly trying to measure up to whatever the United States can do.

“The Chinese would be absolutely incompetent to not be trying to reduce U.S advantage in space,” James Oberg, a former NASA space engineer specializing in orbital rendezvous, tells Danger Room. “No potential adversary in their right mind would give us permanent advantage in space operations.” [Wired.com]

China might not need rendezvous capability to tinker with another country’s satellites, but it would need that capability to spy on them—taking an up-close look at the competitor’s product. There may be no way to gauge true intentions.

According to Oberg, the satellite meet-up occurred in an orbit almost exclusively devoted to earth observation — spy and weather satellites, for example — where “a potential adversary would be most interested in rendezvousing. On the other hand, it’s also where a satellite might need refueling,” he adds. “It’s like you could be changing a screwdriver for a hammer, or you could be turning a peaceful ‘bot into a killer one.” [Wired.com]

Image: ESA

Source: Close Encounters of the Worrisome Kind? Chinese Satellites Meet in Space

9 Ideas For Coping With Space Junk

August 31st, 2010 08:43 admin No comments

An anonymous reader writes “The space age has filled Earth’s orbit with all manner of space junk, from spent rocket stages to frozen bags of astronaut urine, and the problem keeps getting worse. NASA’s orbital debris experts estimate that there are currently about 19,000 pieces of space junk that are larger than 10 centimeters, and about 500,000 slightly smaller objects. Researchers and space companies are plotting ways to clean up the mess, and a new photo gallery from Discover Magazine highlights some of the proposals. They range from the cool & doable, like equipping every satellite with a high-tech kite tail for deployment once the satellite is defunct, to the cool & unlikely, like lasers in space.”

Source: 9 Ideas For Coping With Space Junk

Amateur Danish Rocket Builders Plan to Send a Human to Space

August 24th, 2010 08:56 admin No comments

TychoBraheThe fourth nation to put a person in space, after Russia/USSR, the United States, and China, could be… Denmark?

Denmark indeed. Kristian von Bengtson and Peter Madsen, the leaders of Copenhagen Suborbitals, plan to fire a test flight of their HEAT-1X rocket from the European nation early next week.

This upcoming flight will be an unmanned test flight, but if all goes well, Madsen hopes to be inside the single-passenger capsule named Tycho Brahe for a manned flight in the near future [Universe Today].

The capsule stands about 10 yards tall, and its top is a clear glass dome through which the standing passenger can enjoy the trip to space. (Or at least, try to enjoy it: The cramped passenger will have only minimal arm movement, just enough to operate necessities like a camera, escape hatch, and vomit bag.) The rocket would carry the capsule to the edge of space, where the passenger will be temporarily weightless, and then it will fall in a parachute-slowed descent.

Madsen and von Bengtson are both engineers, and the latter used to work for NASA. But their rocket project didn’t receive government funding; instead they built on a budget of about $63,000 brought in by donation. Says von Bengtson:

“I think our entire budget would barely cover the cost of the key hole on the shuttle. We want to show people that space doesn’t need to be the exclusive domain of big money investments where everything is made out of titanium in clean rooms by people wearing white slippers. We want to give space another face” [The Independent].

OK, but what about safety when you’re building on a non-profit’s budget?

The creators are members of the SomethingAwful web community, and have been posting pictures and answering questions there. In response to one question asking what the chances of the person inside dying are, they replied: “Unlike Columbia we’re not moving at orbital speeds so ‘dying a gruesome death burning up on re-entry’ with our kit has a very low outcome probability” [Wired.com].

(If you’re wondering about the capsule’s namesake, Tycho Brahe, he was a 16th century aristocrat who famously identified a supernova. Some Tycho trivia: He also reportedly lost part of his nose in a duel and lived the rest of his life with a metal replacement. We wish his namesake capsule and its builders a better fate.)

Image: Copenhagen Suborbitals

Source: Amateur Danish Rocket Builders Plan to Send a Human to Space

Geoengineering Could Slow—But Not Stop—Sea Level Rise

August 24th, 2010 08:59 admin No comments

Bay_of_bengalYou could plant huge new forests where none have been before. You could blast particles into the sky to block the sun’s radiation. You could put mirrors in space. These planetary hacks could slow global warming, but one thing that none of them could do, most likely, is to stop the rising sea levels that a warming planet will bring.

That’s the contention of John Moore, lead author of a study out in the Proceedings of the National Academy of Sciences. Moore’s team examined five different means that scientists have proposed to hack the planet and save ourselves from anthropogenic global warming. The geoengineering schemes—forestation, atmospheric aerosols, space mirrors, biochar, and the use of biofuels plus carbon sequestration—are focused either on reducing the amount of energy the Earth absorbs or pulling carbon out of the atmosphere. So Moore wanted to see what they could do about a side effect of the extra heat: melting ice raising the global average sea level.

The results weren’t terribly encouraging. Sea levels respond slowly to changes in the planet’s temperature, Moore told Nature News, so “you can’t just slam on the brakes.”

Injecting sulphate aerosols into the stratosphere – which reduces the amount of sunlight reaching the surface of the Earth – had little effect. If emissions are allowed to grow at current rates, the model showed sea levels rising by 1.1 metres by 2100. Aerosols could reduce that to 0.8 metres by 2100, but with the rate of rise showing no sign of slowing down at the end of the century, this would simply delay greater rises, not prevent them. [New Scientist].

Space mirrors began to reverse the rising sea level trend, but only at about the end of the 21st century. If people quickly developed biofuels and became adept at carbon sequestration, things were even a tad better—but in Moore’s model the sea level still rose by 30 centimeters, or about a foot, mostly because of effects that are already locked into the system. Says Moore:

“I think that sucking CO2 out of the atmosphere is the best way to stop sea-level rise before 2100.” That could be accomplished with the biomass power plants and new forests considered in the study, or by massively scaling up CO2 removal techniques currently deployed in spacecraft and submarines” [ScienceNOW].

Given the unintended consequences that could come with tinkering with the planet on such a massive scale, keeping intervention to a minimum would seem like the ideal choice. But Moore’s study reiterates that fear that it might be too late for little steps. It might be time to consider the “extreme geoengineering”—say, atmospheric aerosol injections every year and a half instead of every four years—that potentially could slow down rising temperatures and sea levels… at an unknown cost.

But once you start, you can’t stop.

Once started, geoengineering must be continued or temperatures will quickly rebound to what they would have been without intervention. An attendant surge in sea-level rise wouldn’t occur quite as quickly, but it would follow soon enough, at a rate of up to 1–2 centimetres per year, he says. “Those are speeds that were observed during the last deglaciation,” says Moore, “so we’re not forecasting anything that is out of the geological record” [Nature].

Image: Wikimedia Commons / Nafis Ahmed Kuntal

Source: Geoengineering Could Slow—But Not Stop—Sea Level Rise

Non-Profit Space Rocket Launching In a Week

August 23rd, 2010 08:17 admin No comments

Plammox writes “A non-profit suborbital space endeavor lead by Kristian von Bengtson and Peter Madsen is trying to put a man in space. The first test of the boosters and space craft in combination with the sea launch platform will take place this week. The catch? All of this is a non-profit project based on voluntary labor and sponsors. How will they get the launch platform out in the middle of the Baltic sea to perform the test? With the founder’s home built submarine pushing it, of course.”

Source: Non-Profit Space Rocket Launching In a Week

Layoff Anxiety Is Top Risk To Space Shuttle

August 22nd, 2010 08:44 admin No comments

pickens writes “Florida today reports that as NASA marches toward its final two shuttle flights, the safety of the crew rests with workers who know every bolt they turn, every heat-shield tile they inspect, brings them that much closer to the unemployment line in April 2011 raising concerns that people might jump ship early if other job opportunities open up. ‘We’ve been most concerned about maintaining and sustaining the knowledge necessary to safely conduct mission operations,’ says Retired Navy Vice Adm. Joseph Dyer. But shuttle work force surveys show a fierce loyalty and a dedication to sticking it out as long term employees want to be there when the last shuttle touches down. ‘They love being part of NASA and what NASA does, and they love being part of the space shuttle program. And they want to be a part of it as long as we’re doing the kinds of things that we’re doing,’ says LeRoy Cain, NASA’s deputy shuttle program manager.”

Source: Layoff Anxiety Is Top Risk To Space Shuttle

NASA Set To Launch Solar NanoSail Into Space

August 20th, 2010 08:02 admin No comments

An anonymous reader writes “Earlier this year the Japanese space agency successfully deployed and used a solar sail to propel its spacecraft Ikaros, and now NASA announced plans this week for its own solar sail mission. This fall it will launch the NanoSail-D into orbit 400 miles up with a Minotaur IV rocket. Once deployed, it will orbit for 17 weeks, proving the technology and allowing astronomers to snap lots of photos.”

Source: NASA Set To Launch Solar NanoSail Into Space

Astronomers Announce Priorities: Dark Energy, Exoplanets, Cosmic Origins

August 16th, 2010 08:16 admin No comments

LSSTThere is a lot of space to explore and a limited amount of money to spend. So every ten years the National Research Council’s “Decadal Survey“  recommends which astronomy and astrophysics projects should get first dibs. Last week, the committee released their recommendations for 2012 through 2021. The projects that got the thumbs-up from astronomers would tackle big tasks, like hunting for dark energy and seeking out new exoplanets.

Though funding agencies (like NASA, the National Science Foundation, and the Department of Energy), Congressional committees, and the scientific community often use the survey to select the observatories on which to focus attention and resources, some were skeptical about this report given the 2001 survey’s recommendations and results.

Although these reports have always been influential—policymakers like scientists to rank their needs—only two of the seven major projects that appeared on the wish list in the 2001 survey have been funded, leading astronomers to wonder if the exercise is as useful as they’d like it to be. Previous surveys have also been faulted for providing unrealistic cost estimates, as low as a fifth of what certain missions have ended up costing. As a result, there has been considerable pressure on the committee that authored [Friday's] report to prioritize projects more effectively and estimate costs better. [Science Insider]

This time, the committee hoped to avoid these budget underestimates by evaluating the financial and technical risk of each project.

“I think at the time of the previous decadal survey, people didn’t appreciate the importance of taking a second look at the cost of things and not just taking the word of the people submitting the projects,” says astronomer Claire Max of the University of California in Santa Cruz, a member of the final survey committee. This time around, the panel hired an outside expert to help estimate the funding and technical risk of each project. [Nature News]

Nature News outlines the survey’s funding recommendations for a wide range of projects, but two observatories–one in space and one on the ground–seem most promising to the committee, fitting with the survey’s major three priorities.

The committee highlighted three main areas of science, none of which should be too surprising to those who follow the field: Cosmic Dawn, New Worlds and the Physics of the Universe. Or, how did all of this get here, are there planets like Earth nearby, and what makes up the universe? Projects that are well suited to answer these questions, as well as technologically feasible, were given high recommendations. [Discovery News]

In Space

The survey recommends the most funding for the Wide Field Infrared Survey Telescope (WFIRST), a joint project between NASA and the Department of Energy, which has an estimated cost of $1.6 billion. After an expected launch in 2020, WFIRST will record light from distant supernova among other things, and hopefully provide insights into the universe’s expansion and dark energy. Committee members also believe the telescope may help in the hunt for exoplanets.

“WFIRST not only gets at all the dark energy [priorities], but it also has significant capability in exoplanet science and will do outstanding work in infrared survey science,” Michael Turner, a cosmologist at the University of Chicago and the Kavli Institute for Cosmological Physics told physicsworld.com. Turner, who served on the 23-member committee for the decadal survey, also notes that the survey did not reject the idea of a possible collaboration with the European Space Agency (ESA) to combine its planned Euclid dark-energy mission with WFIRST. [Physics World]

On the Ground

The survey also recommends support for the $463 million  Large Synoptic Survey Telescope (pictured above). When completed, the telescope will survey the entire sky every week with a three-billion pixel digital camera to help researchers understand dark matter, dark energy, supernovae, near-Earth asteroids, and Kuiper belt objects.

In placing the LSST atop its priority list, the report highlighted the telescope’s technical readiness and its “compelling science case and capacity to address so many of the science goals of this survey,” including exploring the fundamental physical makeup of the universe by probing the nature of dark matter and dark energy. [Scientific American]

The DISCOVER blog Cosmic Variance has more on all this: 
The Next 10 Years of Astronomy explains what the Decadal Survey means to astronomers 
The Next Decade of US Space Astronomy
The Next Decade of US Ground Based Astronomy

Image: LSST Corporation

Source: Astronomers Announce Priorities: Dark Energy, Exoplanets, Cosmic Origins

The Sun’s ‘Quiet Period’ Explained

August 16th, 2010 08:03 admin No comments

Arvisp writes with this excerpt from the BBC:
“Solar physicists may have discovered why the Sun recently experienced a prolonged period of weak activity. The most recent so-called ‘solar minimum’ occurred in December 2008. Its drawn-out nature extended the total length of the last solar cycle — the repeating cycle of the Sun’s activity — to 12.6 years, making it the longest in almost 200 years. The new research suggests that the longer-than-expected period of weak activity may have been linked to changes in the way a hot soup of charged particles called plasma circulated in the Sun.”

Source: The Sun’s ‘Quiet Period’ Explained

Can Solar Storms Cause Wildfires?

August 12th, 2010 08:51 admin No comments

astroengine writes “In the wake of recent solar activity, some space cadets were very quick to point out a causal link between geomagnetic storms and the wildfires currently ravaging the landscape surrounding Moscow. Of course, this is patently false. But is there a scenario when the onset of a solar storm could have secondary effects, sparking fires in already arid regions? Possibly. What’s more, it already happened, 150 years ago.”

Source: Can Solar Storms Cause Wildfires?