Thursday, December 31, 2009

Lunar Lava Tubes

Perhaps the biggest obstacle to colonizing the Moon is the threat of radiation that can be lethal, especially after prolonged exposure. Luckily, rock is good protection against such exposure.

That's why lunar lava tubes are interesting possibilities for sites of bases and colonies. Lava tubes are just what the name implies-- tubes cut through solid rock by flowing lava at some point in the past. Earth has many such tubes, and the Moon, because of volcanism in its history and its low gravity, is thought to have huge tubes-- big enough to shelter bases and colonies.

Scientists working with data gathered by Japan's SELENE lunar probe have found a huge hole in the lunar surface they think might be a collapsed lava tube. The hole is something over 200 feet wide and perhaps 250 feet deep. The scientists think the hole might be a good place for a colony.

Wednesday, December 30, 2009

Russia To The Rescue?

The Russian Space Agency says it plans to launch a spacecraft to the asteroid Apophis that could deflect the asteroid into a different orbit. There is a small chance that Apophis could collide with Earth in 2029.

Developing a planetary defense capability is certainly a necessary long term project, and Russia says it will invite other nations to participate in the mission.

Refinements in Apophis' orbit show the chance of a collision is much less than first thought.

Tuesday, December 29, 2009

Hubble Goes Tiny

The Hubble Space Telescope has earned its place in the history of science by imaging big stuff that is far away in both space and time. Now, it has also found a tiny object far out in the Solar System.

A team of researchers has used HST images to find a body in the Kuiper Belt beyond Neptune that is only roughly a half mile across. Previously, the smallest object found in the Belt was 30 miles across.

The object was not directly imaged. Rather, the team looked for occultations-- blinks-- of background stars. By noting the duration of the blink, the team could work out the size and speed of the object that moved in front of the star.

Monday, December 28, 2009

Chicxulub Firestorm Questioned

For the past several years, the generally accepted story of the demise of the dinosaurs included a worldwide firestorm as tiny, hot pieces of earth were thrown up by the asteroid impact that caused the Chicxulub crater off the modern Yucatan. Those pieces were supposed to have ignited forests around the world as they landed.

A new computer model suggests, however, that most of those pieces did not land immediately. Instead, they formed an opaque cloud well up in the atmosphere that actually blocked other pieces from hitting the surface. The world did heat up, according to this model, but not as much as the accepted theory holds, and there was no worldwide firestorm.

Sunday, December 27, 2009

The Local Fluff

Out on the very edge of the Solar System, where the two Voyager spacecraft are approaching interstellar space and still sending back data, astronomers have found a region they've dubbed "The Local Fluff."

The area seems to be about 30 light-years wide, and sits between interstellar space and the Sun's heliosphere-- the home of the Sun and its planets. The Fluff contains hydrogen and helium, and has a magnetosphere. That magnetic sphere is probably the most important feature. Emerging data suggests a star in the neighborhood exploded perhaps 10 million years ago, and scientists think the magnetic field of The Fluff helped protect life on Earth, and the rest of the Solar System, from the resulting burst of powerful radiation.

Thursday, December 24, 2009

New Telescope Almost Operational

Infrared astronomy is one of the fields that revolutionized mankind's understanding of the universe in the twentieth century. By expanding astronomy beyond the limited visual scope humans see, scientists have been able to gather data that had been unavailable, deepening our insights into how things work.

NASA's new Wide-field Infrared Survey Explorer is currently undergoing final, on-orbit checks. So far, everything is fine. Within a month, NASA hopes to have the first images from its new window on the universe.

Wednesday, December 23, 2009

The ISS Five

After a successful Soyuz launch Sunday, three more people joined the ISS crew today, bringing the current number of crewmembers to five, one below the usual goal.

This five probably wouldn't make a good basketball team, but it will be able to conduct more scientific research than the two-man skeleton crew the three new arrivals augmented, which is good news.

Tuesday, December 22, 2009

More Evidence Of Martian Water

All the wheel spinning the Mars rover Spirit has done over the past few months, trying to free itself from deep sand, has produced some data that wouldn't have been gotten otherwise.

Spirit's wheels haven't been able to get enough traction to drive Spirit away, but they have broken through the surface crust and dug through the next layer of sand. Beneath the surface, NASA has found sulfate material. Sulfates are formed in the presence of streaming water, or in hot springs. The odds are surely long against one of the early Mars rovers just happening to get stuck on the site of an ancient hot springs, which in turn suggests water once flowed rather freely on Mars.

It's one more piece of evidence for a wetter Mars in the past. That's good for those looking for Martian life-- and for those planning future human missions to the planet.

Monday, December 21, 2009

Spirit's Wheel

Mars is full of surprises, and so, it seems, is the Mars rover, Spirit.

Spirit's right front wheel stopped working in 2006, due to an open electrical circuit, and engineers assumed it was lost for good. Since then, as a consequence, Spirit has been driven around Mars in reverse. Last week, however, attempting to extricate the rover from the deep sand that's had it trapped for months, engineers took a shot and tried to use the dead wheel. It spun.

It didn't spin easily, and it didn't get the rover unstuck, and it has since stopped spinning, but the wheel did respond to commands. Team members are allowing publicly that they may never get Spirit moving again, but the unfrozen wheel is a reminder that strange things can happen on the Red Planet.

Sunday, December 20, 2009

ExoMars On Track

The European Space Agency has secured funding for the joint ESA/NASA ExoMars mission to launch in 2016 and 2018. ExoMars will include an orbiter, a lander, and a rover.

ESA officials say they will spend the next year negotiating with NASA to determine the exact role and responsibilities of each partner in the mission and will seek final approval for the mission from ESA member governments in 2012. They also say the budget for ExoMars of roughly $1.23 billion is a hard limit. Cost overruns could result in cancellation of some element of the mission. Any additional funding will require a unanimous vote of the member governments.

Of course, NASA will have something riding on a fully successful mission, as well. It's possible the Europeans might feel comfortable taking a hard line on the budget because they feel NASA might well pick up more of the tab rather than allow a headline Mars mission to be reduced in scope.

Friday, December 18, 2009

AVATAR

Today is opening day for James Cameron's much-hyped science fiction movie, Avatar. The project is said to set new technical standards for filmmaking, and with a budget of $400 million, it probably should.

The plot of the movie, judging from pre-release material on television, is much less avant-garde. Humans seem to be engaged in the military conquest of a people living on an extrasolar planet. Not only is that theme unfortunate, it's arguably unlikely. Projecting military power is hugely expensive. Projecting it into another star system would seem both a colossal waste of resources and a bizarre policy choice. Another problem with the movie might be its choice of alien. They might be ten feet tall, blue, and tough to kill, but they are definitely humanoid. Yes, the Screen Actors Guild only has humanoid types, but shouldn't that much money and that much technology get truly alien aliens?

Hopefully, by the time humans are capable of interstellar travel, we will also have left the notion of military conquest as a good thing far, far behind.

Thursday, December 17, 2009

Second Life For Phoenix?

The Mars Phoenix team lost contact with the Lander in November, 2008, as the harsh Martian winter closed in over the probe. Lander's electronics were not designed to survive the bitter cold of the Martian arctic, so everyone thought the mission was over.

Well, maybe not.

Next month, JPL engineers are going to try to re-establish contact with Lander. At last contact, all the cameras and scientific instruments were still working well, so if the electronics did survive the winter and contact can be regained, there's some chance that the scientific work could be picked up where it was left off.

Peter Smith, leader of the Phoenix team, says reviving the mission is unlikely, but worth a try.

After all, NASA's Mars rovers were designed to last 90 days, and they're both going on six years.

Wednesday, December 16, 2009

Nearest Black Hole

New measurements show that the nearest black hole to Earth is only about half as far away as previously thought. Don't worry, though. There's still about 7,800 light years between it and us. That's a huge distance, even for something as powerful as a black hole.

Of course, our current search techniques aren't perfect, and the various objects in the galaxy are in constant motion, so there's no guarantee astronomers will never find a black hole closer to us than the current record holder. However, the Earth has been around for 4.5 billion years or so, and there's no reason to think it won't be around, orbiting a life sustaining Sun, for a very long time to come.

Black holes are not things to worry about, in any case. Time and energy and worry are best directed at matters that can be altered by human effort-- curing disease, ending wars, grappling with widespread poverty. If a black hole did have Earth in its crosshairs, there's absolutely nothing we could do about it. Not now, and not for thousands or perhaps millions of years.

Tuesday, December 15, 2009

ALH84001

In 1996, a team of NASA researchers made big news by announcing they had found evidence for life on Mars in a meteor that had come from Mars. The meteor had been the first found in 1984 in the Allen Hills of Antarctica, and had been labeled ALH84001.

The claim was controversial. Many scientists argued the tiny structures inside the rock the NASA team saw as fossils could have non-biological explanations. Supporters of the life theory often conceded that point, but argued the most likely explanation was life.

After a decade of intensive study of Mars by numerous spacecraft designed to pursue numerous approaches to data-gathering, the case for life on Mars-- either in the past or currently existing-- is far from clinched. However, an argument for a warmer, wetter Mars early in its history-- and perhaps fairly recently-- seems to be strengthening. That Mars, of course, would have been more conducive to life.

Using better tools and more knowledge than were available in 1996, a team at NASA's Johnson Space Center in Houston, which, it should be noted, included the key members of the 1996 team, has reexamined the meteor. The 2009 conclusion? The most likely explanation of the structures in the rock is Martian life.

Monday, December 14, 2009

Dragon To ISS

SpaceX's cargo capsule Dragon is scheduled to make the first of three demonstration flights to ISS between May and November next year. During that time three astronauts who have worked with Dragon will be aboard ISS if all goes as planned, and the company has said the first Dragon flight will take place when an astronaut familiar with the vehicle is on board the space station.

That's more important than it may seem at first blush. Dragon will not dock with the station. Instead, like Japan's cargo ship, Dragon will simply fly close enough to ISS for a robotic arm, operated by an astronaut, to grab it and bring it into the station.

SpaceX's Falcon 9 launcher will carry Dragon to space, and the first flight of that configuration is scheduled for early next year. After the three demonstration flights, SpaceX already has a contract with NASA to fly 12 cargo flights to ISS through 2015. That contract is worth $1.6 billion. The company is also working on man-rating both Falcon 9 and Dragon so that the company could ferry crews between Earth and low Earth orbit.

Sunday, December 13, 2009

Iapetus Explained

For over 300 years, astronomers have known there was something odd about Saturn's moon, Iapetus. The leading hemisphere is much darker than the trailing. Recent images taken by the Cassini spacecraft confirm the leading explanation of the contrast.

As Iapetus orbits Saturn, dust-- perhaps from other moons, perhaps from Saturn's rings-- falls onto the leading hemisphere. Dust is much darker than ice, hence that hemisphere has become darker. Reinforcing the process, the layers of dust slightly warms the surface, which allows water vapor to migrate to the trailing hemisphere, where it freezes back into ice. The small size of Iapetus-- about 900 miles in diameter-- and, therefore, its low gravity also aids the migration of the water vapor, further supporting the entire process.

Friday, December 11, 2009

Spirit Wheel Problem

NASA's Mars rovers each have six wheels. Opportunity, after nearly six years on the planet, continues to roll right along.

Spirit, however, has had more problems. It has been functioning without an operating right front wheel since 2006, and for the past several months has been stuck in deep sand. During NASA's recent attempts to extricate Spirit, the right rear wheel has stopped spinning, perhaps permanently. The rovers were designed to function on four wheels if necessary-- three, if the right three-- but NASA isn't sure Spirit can get out of its current predicament with two dead wheels.

A time factor is also beginning to loom. Winter at Spirit's location on Mars begins in May 2010. Given the precise way the rover is situated, NASA doesn't believe it could gather enough solar energy to survive the winter. So, the fight to save Spirit might be reduced to a simple imperative. Move or die. In six months.

Thursday, December 10, 2009

Saturn's Hexagon

One of the most bizarre things yet found in the Solar System is the hexagon of clouds that extends deep into Saturn's atmosphere directly over the planet's north pole. For the past several years, the area has been in darkness during Saturn's northern winter, but it is now emerging into light, and Cassini is taking the best pictures yet of the formation.

A jetstream of wind surrounds the formation, seeming to hold it together. Coming off each of the six corners is a wave of wind. Exactly how those features explain the formation is completely unclear at the moment, but the hexagon has been there for at least thirty years, so scientists will probably have plenty of time to puzzle it out.

Wednesday, December 9, 2009

Getting MRO Back

NASA's Mars Reconnaissance Orbiter has been out of the data gathering business since August, when it put its main computer in safe mode. The craft had also had computer problems in February and June, so when the August event occurred JPL engineers decided to do a thorough study of MRO's software.

That study completed, JPL started uploading software fixes to the probe a couple weeks ago, and engineers hope to be getting data from MRO again by next week. That would be a big plus for Mars science. MRO is the most powerful of the probes currently orbiting Mars, and even with its computer problems has sent back more data about the planet than all other Mars probes combined.

Tuesday, December 8, 2009

Space Junk Conference

A conference seeking ways to deal with the space junk problem is being held in Washington this week. It is sponsored by NASA and DARPA-- two agencies famed for their high tech expertise.

An estimated 300,000 objects of one centimeter across or larger are whizzing around low Earth orbit. They are the core of the problem. Even a tiny piece of debris traveling at several times the speed of a bullet fired from a high-powered rifle could cause great damage to the thin skin and delicate electronics of a satellite, for example. Such debris could also be a real threat to manned spacecraft and astronauts' EVA spacesuits.

There is no shortage of possible technical fixes. The real tough parts of solving the problem may lie elsewhere. For example-- who will pay for the cleanup? There are also legal and national security issues to be worked out. After all, a technology that could take a dead satellite out of orbit could presumably also take a live, important satellite out. Solving that problem and finding effective ways to control the technology central to dealing with larger pieces of debris is key to dealing with the overall issue.

Monday, December 7, 2009

Not Only In America

A steady refrain of space program critics in America is that major NASA programs consistently run way over budget. Those folks, it should be noted, constitute a subset of critics of programs that run over budget across the scope of government activity. NASA is not unique, and could do better if Congress was more concerned about the budgeting needs of highly complex new technology programs. Political calculations, however, too often trump fiscal ones, for NASA, Defense, and a myriad of other government projects.

Budget overruns don't only happen in America, though. Japan's government seems on the verge of canceling a major rocket development program, the GX, because of large budget overruns in a bad economy-- and because Japan's current workhorse rocket is performing exceedingly well.

Watching how the worldwide recession affects space development over the next few years will be interesting. To the extent it makes financing private space companies more difficult, the financial collapse might delay the corporate expansion into space, and put the leadership of the drive into fewer hands. Whether that would be good or bad will be the judgment of future generations to make. Government space efforts will likely be cut back, but the tough economic environment and the need to create good jobs may work to internationalize large space projects. The building of ISS could serve as a model both of how to proceed and what to avoid. Establishing an international lunar base is an obvious example of a reasonable, useful project that has appeal in several major nations.

Sunday, December 6, 2009

Milestones

Today marks the thirty-seventh anniversary of the launch of Apollo 17-- the last Apollo mission to the Moon. Tomorrow, December 7, will be the sixty-eighth anniversary of a turning point in modern history, the Japanese attack on the U. S. Navy's Pacific Fleet in Pearl Harbor, Hawaii. Far from securing Japanese dominance in the Pacific, the American response to the attack led to the United States achieving superpower status and the American leadership of the Free World in a tense contest with Communist totalitarianism. That contest gave birth to Apollo.

Tomorrow will also see the unveiling of Virgin Galactic's SpaceShipTwo, which will be the first craft to provide paying custoners suborbital flights to the edge of space. VG plans to commence those commercial flights in 2011, assuming planned test flights go as expected. SpaceShipTwo will carry six passengers and be operated by two pilots. VG already has 250 confirmed customers; at six a pop, that's more than sixty flights already filled. At $200,000 per ticket, VG already has $50 million in ticket sales alone.

SpaceShipTwo will be unveiled in Mojave, California, near America's Pacific Coast.

Friday, December 4, 2009

Pondering Safety

Congress has begun a process aimed at developing a safety regime that would allow NASA astronauts to fly to orbit aboard commercial spacecraft. Currently, between the retirement of the space shuttle, likely in 2011, and the first flight of Orion, which might be delayed until 2017 because of budget problems, astronauts will have to hitch rides in Russian Soyuz capsules. For various reasons, many people are unhappy about such a Russian monopoly of access to a largely U. S.-built space station.

Of course, at the moment there are no commercial human-rated spacecraft, much less any capable of orbital flight, but there are companies working towards that goal. SpaceX and Orbital Sciences already have contracts with NASA to build cargo ships that will take supplies to ISS, and both are looking at transforming those unmanned vehicles into human-rated capsules. Several other NewSpace companies-- plus, perhaps, Lockheed Martin and Boeing-- are also trying to develop manned spacecraft. One, Interorbital Systems, plans a private orbital flight in 2011.

Before NASA will risk astronauts' lives in such vehicles, however, the craft will have to meet NASA safety requirements. The U. S. House committee with oversight of space policy has held hearings gathering testimony and facts about the safety issue. The committee is urging NASA and the FAA to cooperate in developing safety standards for commercial craft. NASA says it would probably take three years for it to be satisfied that a commercial spaceship was safe enough to fly astronauts. Three years doesn't seem an inordinate amount of time if a new company can get NASA's seal of approval.

Thursday, December 3, 2009

Servicing ISS

Extending the lifetime of ISS beyond its current termination scheduled for 2015 would require cargo flights after 2015, and Europe and Japan are beginning to look at ways to pay for additional flights of the cargo ships they have developed.

The Augustine committee probably reflected the views of many in the space community when it argued ISS should be extended at least through 2020. Taking twenty years to complete the station and using it in its full capability for only four years makes very little sense, yet that is the current U. S. plan.

Europe and Japan both might run into budget constraints as the governments involved try to navigate the current economic downturn. As has happened in the U. S. for decades, when governments want to show they're being fiscally prudent, space budgets seem to be among the first to be slashed. If Europe and Japan fail to get funding, supplying ISS would fall to Russia, and perhaps to U. S. commercial carriers just now developing the necessary craft.

Wednesday, December 2, 2009

Space Solar Power

The idea of powering human civilization by collecting energy fron the Sun in huge satellites and beaming it into Earth's electrical grid has been around for decades. If things go right, the concept may finally be tested soon. Japan is studying a plan that would allow that island nation to get a large percentage of its energy from space-based solar by the 2030s. California is looking at a proposal to develop space-based solar as a viable energy alternative in fifteen years, and various other governments and private companies are looking at what's possible.

In a world quickly approaching nine billion humans, with expensive energy and climate damage, getting clean, limitless energy from the Sun is certainly attractive. At some point, the cost of space-based solar will be competitive with, say, oil, as that resource gets harder and harder to develop. Nor does space-based solar have the potential for disaster nuclear plants have. The guts of a SSP system, the huge satellite, would be beyond natural disasters, and would be beyond the reach of terrorist and most military attacks. Indeed, a mature SSP system would be a decentralized system; attacking one satellite would make very little sense.

Getting the energy from space to Earth is still a problem. Microwaves and lasers have been proposed as possible modes of delivery, but their effects on the atmosphere are still unclear. Building huge structures in space and keeping them properly oriented and maintained for decades or longer are still likely engineering feats beyond our capability, too, but that can change. In 1961, putting a man on the Moon and safely returning him to the Earth was utterly beyond any human agency-- but it wasn't by 1969.

Tuesday, December 1, 2009

SuperEarths And Life

Harvard astronomy professor Dimitar Sasselov coined the term "SuperEarth" to refer to worlds similar to Earth, but with two to ten times the mass. Now, Sasselov is arguing such worlds might be better able to support life than our own.

He bases his argument principally on increased geologic energy on the more massive planets-- especially more efficient plate tectonics. That's important because tectonic shifts release carbon into the environment, and carbon is essential for life. Sasselov goes on to speculate that most civilizations might, therefore, be found on SuperEarths, and suggests that might explain why Earth hasn't been visited by aliens. Either the aliens haven't developed the technology to allow them to escape the deep gravity well of their home planet, or they see smal worlds like Earth as unikely homes of life.

Not to question a Harvard astronomy professor, but an extremely active planet geologically-- with volcanoes constantly erupting and the surface in a constant state of change-- doesn't seem like a good place for advanced civilization to rise and thrive. Life, perhaps; civilization capable of space travel, maybe not. There is also the matter of that strong gravitational field. Surely such a planet would tend to bring even more comets and asteroids to itself than Earth does, and we know life on Earth could be extinguished under such a bombardment. Increase the number of objects coming in, and the speed with which they hit the surface under the stronger gravity, and sustaining life might be problematical.