Sunday, September 18, 2005
The Big Solar Flares Of 2005 And Human Settlement Of Space.
A Coronal Mass Ejection hit the Earth on September 7th producing some auroras. According to NASA, this month's solar activity "[w]ith the exception of brief radio blackouts, the flares have had little effect on Earth, although the NOAA Space Environment Center warns that as the spot continues to rotate toward Earth, agencies impacted by space weather storms may experience disruptions over the next two weeks. These include spacecraft operators, electric power systems, high frequency communications, and low-frequency navigation systems."
The JPL Rover home page (here) has no information whether the flare activity has had any effect on Spirit or Opportunity. Nor do Mars Odyssey, Mars Global Surveyor or Mars Reconnaissance Orbiter. (Here, here, and here.)
Things have not always gone so well.
According to this NASA report from Summer 2004 (here) "the MARIE instrument on the Mars Odyssey spacecraft was not as lucky. Ironically its task was to better understand solar radiation on Mars. It was able to make observations up until a powerful Oct. 28 CME overheated a power converter." And this report (here) describes the radiation risks to astronauts on the Moon without an atmosphere or magnetic field to protect them from solar flare activity. The bottom line is that solar flare activity is a danger to people and machines in space beyond the protection of Earth's magnetic field.
Mars has no global magnetic field and a very thin atmosphere. Humans and machines there are at risk from the kind of solar activity that does little more than cause annoying radio blackouts and beautiful auroras here on Earth. This is often described as not being a show stopper because it's an engineering problem that is solvable: for instance, by building Mars homes underground, using water as a radiation shield, generating magnetic fields to protect ships and bases, or even building spaceships with plastic (here).
Advocates of human spaceflight often say that we have to settle other planets, particularly Mars, because we don't want to leave all our eggs in one basket on Earth. For instance, if an asteroid hit the Earth, civilization would die if there were no colonies on other planets.
Yet a glance at Mars, for example, reveals a planet that is pocked with impact craters all over its surface. There's no big moon in the sky with a gravity well that could lure passing asteroids to strike it rather than Mars. Not coincidentally, Mars orbits fourth from the Sun, right next to the Asteroid Belt. Indeed, the moons of Mars are believed to be captured asteroids. Mars has no planet-wide magnetic field for protection from solar radiation. The atmosphere is 1/100th as dense as Earth's and it has almost no oxygen. The ground is regolith not soil and is covered with peroxides and dust. The winds of Mars, even with the thin atmosphere, whip up planet-wide dust storms that can last for a month. The dust is probably as sharp as the dust of the Moon because of the lack of moisture. The dust of the Moon is so sharp that it shredded the gloves of astronauts who visited there. The gravity is only 38 percent of Earth's.
Yet Mars is often described as the best location for settlement because it is the most Earth-like planet in the solar system. A better term would be "least inhospitable Earth-type" rather than "most Earth-like."
Mars and the other worlds of this solar system seem like awfully harsh new baskets to put our eggs in. Where would you bet on a global catastrophe occurring first, Earth or Mars?
But it's human destiny to settle the Solar System and I'm all for it. We've spread from Africa to cover the Earth and we are now traveling off planet. Our history of migration tells us it's inevitable that one day we will build colonies then cities and civilizations on the other worlds of the Heliosphere. But the other planets have much harsher environments than the Earth. Life there will be much harder than on Earth and people will have a more tenuous grip on survival. Future space settlers would do well to maintain close relations with Earth, the safest basket of them all for humanity's eggs.
Saturday, September 17, 2005
Views Of Space From Beyond Earth's Orbit.
Another favorite of mine is the view of Earth from the Mars Global Surveyor in orbit around Mars. (Story here.) (Photo credit: NASA/JPL/Malin Space Science Systems.)
Two new favorites are these time lapse photos of the moons of Mars taken by the Spirit rover. (Story here.)
(Photo credits: NASA/JPL/Cornell/Texas A&M.)
I've never been able to visualize in my mind what Phobos and Deimos look like in the Martian sky. These pictures really help in understanding how the moons of Mars look in the sky. Deimos looks almost like a distant planet while Phobos looks like what it probably is, an asteroid trapped in Martian orbit.
Meanwhile, back on Earth we see the familiar sky above us as we wait for Monday's announcement of NASA's architecture for sending humans back to the Moon and on to Mars. And as we wait we wonder how long it will be until humans see these vistas with their own eyes. Not soon enough.
Saturday, September 10, 2005
Flawed Top Ten Alien Abduction Movies
I can't agree.
The best of this genre is actually their number 3 pick, the original Invasion of the Body Snatchers. Body Snatchers set the standard for this genre and it holds up today even though it was made way back in 1956. The themes it developed are as relevant today as they were then.
On the other hand, the X-Files TV series was gripping and many of its episodes are worth a second look, particularly the horror episodes that did nothing to advance the absurd UFO government conspiracy plot. But the X-Files movie was utterly forgettable.
Another flaw with Space.com's list is te absence of the excellent mystery thriller from last year, The Forgotten. That movie starts as a story about a mother who cannot cope with the loss of her young son. But as the movie progresses it reveals itself to be an alien abduction story that presents a plausible explanation as to why the aliens are taking humans and how they get away with it. If you want to see a good movie of this genre, rent The Forgotten and leave the X-Files movie on the shelf.
Monday, September 05, 2005
Tourism Opportunity At Valles Marineris
Here on Earth somebody has proposed building a glass-bottomed walk jutting out from the rim of Arizona's Grand Canyon. (Story and artist's rendering are here.) The view down is about 4,000 feet, less than a mile.
Imagine something similar at Valles Marineris with its 4 mile drop. Bring your camera and a telephoto lens!
They Don't Make Heroes Out Of Metal And Microchips
On the drive from Boulder home to San Diego after the Mars Society conference my fellow members of the Mars Society of San Diego and I stopped at Meteor Crater near Winslow, Arizona. The site is an impact crater in the Arizona desert where long ago a meteorite hit the Earth. Today it's a park where the crater is preserved and a museum tells visitors about meteors and meteorites and craters. It is one big hole in the ground.
There is no particular reason why this location should have anything that commemorates human space exploration but in the entry courtyard there is an Astronaut Wall of Fame that lists the names of all the American astronauts.
You can search in vain for a list of the robots and unmanned probes that the United States has sent into space. They don't make Walls of Fame for robots that get sent to outer space. Walls of Fame are built to honor heroes and it takes flesh and blood to be a hero. It's humans in space that people care about and it's humans in space that inspires others to support space.
Dr. David Livingston talked about this a bit in a presentation he gave at the Mars Society Conference. His talk described the results of his economic study of the costs and benefits of government spending on the Apollo program versus spending on other public works projects. In this case, the Federal School Breakfast program and Hoover Dam.
This post is not intended to relate all of Dr. Livingston's conclusions on the relative merits of the three programs. But one conclusion he drew about the merits of government spending on human space exploration is important. Dr. Livingston concluded that the Apollo program continues to provide economic benefits to the American economy, and other economies, 30 years after the program ended.
Besides the technological spinoffs, Apollo continues to provide benefits because it was an inspirational program that created a generation of people who were motivated to choose their careers because of what Apollo accomplished. The contributions of this Apollo generation are felt today.
Dr. Livingston's research led him to conclude that the capability to inspire is the hallmark of a successful government space program. Although he didn't exactly put it in these terms, what I think he was talking about, was that Apollo produced heroes who inspired others to follow the trail they blazed.
The American space program has limped along since Apollo without a destination and that has been its failure. Its astronauts have gone nowhere interesting and have been reduced to playing the role of glorified delivery drivers. Although some people may have been inspired to join the space program because of the space shuttle or the space station, one wonders who really wants to be part of a human space program that does little more than send people up to space carrying supplies and back down to Earth carrying trash. In fact, what the post-Apollo American space program really seems to have done is to drive those people who were inspired by Apollo to look elsewhere to get into space. Witness Space Ship One, Virgin Galactic, the private space societies, and the stirrings of the new alt-space industry. Those motivated to going somewhere in space have been forced to seek their own way.
What effect the Vision for Space Exploration will have remains to be seen. It is still in its infancy and it has not yet created the heroes that Apollo created. Also the polarization of American politics threatens the Vision because it is at risk of being seen as President Bush's idea rather than the natural expression of America's frontier spirit.
But the dream is alive for some. Witness this engraving in the lower corner of the Astronaut Wall of Fame at Meteor Crater.