14 September 2010

A little exopolitics realism for you?
"Man, the State, and Aliens: An Investigation of Unifying Threat in Structural Realism"
http://www.claremontmckenna.edu/keck/research/AustinThesis2010[1].pdf







From: http://www.kuffodog.com/blog/?p=86
Now for my hypothesis: The rotational speed of the Earth, amounted to thirty something hours per day (one full rotation) at the time when first humans appeared. This explains why to this day humans exhibit a natural tendency to establish an extended circadian rhythm when given free choice. This hypothetical change in rotational speed might be something worth investigating.
The most obvious explanation for the increase in the Earth’s rotational speed that immediately comes to mind are collisions with asteroids. That serves as yet another reminder that a planetary defense system must be developed and the time to do so is running short.

From: http://www2.rosa.ro/index.php/en/communication/events/477-pdc2011.html 
2011 IAA Planetary Defense Conference: From Threat to Action
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logo_pde_smallThe International Academy of Astronautics will hold its second conference on protecting our planet from impacts by asteroids and comets from 9 - 12 May 2011 in Bucharest, Romania.
The 2011 IAA Planetary Defense Conference: Protecting Earth from Asteroids, co-sponsored by the European Space Agency and The Aerospace Corporation, is the follow-on to three previous planetary defense conferences held in 2004 in Los Angeles and 2007 in Washington, D.C., and in 2009 in Granada, Spain. The theme for the conference is “From Threat to Action”.
The official conference website link is http://www.pdc2011.org.
For the upcoming conference in 2011, the call for papers is now open - for further details, see the menu item on the left on the official conference website.

From: http://science.discovery.com/tv/sci-fi-science/episodes.html 
Deep Impact
Airs Wednesday, September 8 at 10 PM E/P

Dr. Michio Kaku is on a mission to save planet Earth. Nearly 90 percent of the rocks in space are big enough to destroy our civilization. And it's not a question of if they'll hit our planet, but when. He shows what would happen if we really did use nuclear weapons to blow up an incoming asteroid and comes up with a safer, rocket-powered solution. Kaku meets up with Harvard's Professor Brian Marsden, who explains how a massive comet could smash into Earth without warning. To deal with the multiple threats, Kaku takes a lead from Star Wars and designs a system of laser-equipped Death Stars to zap the space rocks before they hit us.

From: http://www.audubonmagazine.org/fieldnotes/fieldnotes1009-solar.html

Courtesy of Japan Aerospace Exploration Agency (JAXA)
Solar Power
Space Race
Companies are competing to reap energy from the heavens.

Picture a massive, solar cell-lined satellite hovering in outer space. The solar panels continuously collect light from the sun, making energy that’s beamed to earth, where it’s transformed into clean electricity.
It sounds like science fiction, but space-based solar power (SBSP) is quickly becoming a reality. “The idea has been around since the 1960s, but the technology was way behind the vision,” says William Maness, chief technology officer at SBSP company PowerSat. “Now we have computers the size of our watches and thin-film solar cells thinner than a piece of paper. The economics have changed.”
Several companies aim to capitalize on those technological innovations and the world’s growing interest in renewable energy. In January the California Public Utilities Commission green-lighted a power purchase agreement between Pacific Gas and Electric and Solaren Corp., which plans to produce 200 megawatts of SBSP by 2016, enough energy to power thousands of homes, says Cal Boerman, the company’s director of energy services. The Japanese Aerospace Exploration Agency aims to generate 100,000 megawatts with SBSP by 2035. With projects also in the works in China and Europe, the quest to launch the first SBSP system is quickly becoming the next great space race.
Collecting energy in space offers significant advantages over ground-based systems. “The intensity of sunlight is about seven times higher in space, and you can get it 24/7,” says Marty Hoffert, cofounder of Versatility Energy, an SBSP company. With microwave systems, solar power can be beamed to earth even during cloudy days and inclement weather.
The biggest hurdle may be the price tag: Solaren’s project, for instance, will cost billions, with much of the expense coming from rocketing equipment. Some say the systems need to be more efficient, and the technology has yet to be demonstrated in space. Plus, beaming solar power at night will increase light pollution. “It seems like an exciting idea,” says Ken Zweibel, director of George Washington University’s Solar Institute. “[But] it’s impractical because it’s an order of magnitude or more in cost than terrestrial solar, and it’s unnecessary because terrestrial solar is going to work very well.”
“It will cost billions of dollars, but any nuclear plant of similar capacity costs the same,” counters Maness. “We can do something cleaner and get you the same amount of power.”

http://www.unexplainable.net/NASA/Large-Asteroids-Aren-t-A.shtml

Large Asteroids Not A Threat, Small Ones Are

By Chris Capps    9/9/10


Asteroid_3.jpg
While the idea of a large planet killing asteroid makes for a great film, the truth of the matter is, there's an ever slimming chance that Earth will be hit by one as astronomers chart more of the skies and find them to be exceedingly rare.  On the other hand, several objects capable of wiping out entire cities do seem to exist and may pose a serious threat to the planet.

It doesn't seem the world will end any time soon in our lifetimes as planet killing asteroids no longer seem to be a real possibility.  In 2004 the asteroid Apophis was considered the most likely object to impact Earth, and the asteroid was of sufficient size and speed that it could have disrupted the Earth in ways resulting in global destruction or at the very least massive Earth changing catastrophes in 2029 or 2036.

While some are still terrified of the potential approach of the Apophis asteroid, most scientists at NASA have declared the chances of the Apophis asteroid hitting Earth so small that it is likely not going to be a threat we will ever see in our lifetimes.

But there are many other asteroids, many capable of creating explosions powerful enough to level entire cities or hit the ocean and cause massive tsunamis.  The incredible power of even a moderately sized asteroid is enough to disrupt the entire economic system and potentially put millions of lives in danger.  Currently less than $5 million is dedicated to the search for dangerous incoming asteroids.

The topic is split largely into two categories of unhappy people.  The first group suggests that five million dollars annually is a waste of money.  They say an asteroid hasn't hit the Earth since 1901 during the Tunguska event and even then the chances of it impacting an inhabited area of the globe is remote at best.  These people obviously want no research into a potential defense system against asteroids.  The other group, those who fear a massive asteroid collision with Earth suggest that $5 million out of a massive defense budget which totals over $1.5 trillion annually.  This group believes that a planet that spends most of its money on defense should have a better strategy at defending itself against the potential threat of an incoming asteroid.

If one were to take one third of the amount spent on military housing in the United States' Air Force, this would be more than sufficient for a planetary defense system scanning 90 percent of the skies as opposed to the current 10 percent.

So the good news means the Earth will not be destroyed entirely by a planet killing asteroid.  At least the chance is infinitesimally small according to scientists.  On the other hand, it's far more possible we will be hit by a smaller asteroid capable of causing quite a bit of damage but leaving most of the human race intact.  Will we be sufficiently prepared in the event of an impact?

From: http://www.itwire.com/science-news/space/41752-nasa-considers-asteroid-impact-with-earth
NASA Weighs Asteroid Danger
Some time in the next decade, a US president will probably be presented with this dilemma: is it worth spending US$1 billion to deflect a space rock that may never hit Earth?
A NASA panel is wrestling with this question, which is growing more pertinent as scientists’ ability to find asteroids that pose a potential risk, termed near-Earth objects (NEOs), outstrips their capacity to track them accurately. The Ad-Hoc Task Force on Planetary Defense , set up to suggest ways for the agency to protect Earth against a deadly impact, is expected to release its report next month. But public deliberations and interviews with its members have revealed their thinking.
The dilemma stems from a 2005 congressional mandate directing NASA to log 90% of the estimated 20,000 NEOs larger than 140 metres in diameter by 2020. NASA seems unlikely to meet the goal, but the agency is stepping up its detection and tracking of smaller objects.
That will create a new problem: if the pace of NEO detections (see graph ) grows but precision tracking of orbits lags behind, observers will start to find more rocks ” perhaps a few per year ” that seem, at first, to have a significant chance of hitting Earth, say panel members. “I don’t think that issue has been understood outside the NEO community,” says Lindley Johnson, NEO programme officer at NASA and a member of the panel. Launching missions to track or deflect all potential asteroid threats will be prohibitively expensive, but even a small probability of regional or global devastation may not be politically palatable.
One solution from the panel is to increase the amount that the United States invests in NEO detection and tracking from the current $5.5 million a year. The panel may also recommend the launch of a survey telescope into a solar orbit similar to that of Venus. It would orbit faster than Earth and, looking outwards, would see asteroids in Earth-crossing orbits more often than would ground-based instruments (see diagram ). This could improve follow-up observations, narrow estimated trajectories and remove as many asteroids as possible from the threat list. It could also spot and track asteroids on the sunward side of Earth, removing a worrisome blind spot in ground-based surveys. “It is a wonderful rapid technique to track bodies down to 140 metres and smaller,” says Tom Jones, a former astronaut and panel co-chair.
Ball Aerospace and Technologies Corporation, a manufacturer of spacecraft based in Boulder, Colorado, has proposed building such a remote scope at a cost of $600 million. But Irwin Shapiro, an astrophysicist at the Harvard”Smithsonian Center for Astrophysics in Cambridge, Massachusetts, who chaired the 2010 Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies for the US National Research Council, says that ground-based observatories such as the planned Large Synoptic Survey Telescope (LSST) on Cerro Pachn in Chile are better value for money than space telescopes, because they last longer and are less expensive. He says the LSST is also more likely to command funding, as it is the top priority recommended by the Astronomy and Astrophysics Decadal Survey, released in August by the National Academies. Putting a space telescope in a Venus-like orbit “would in effect start from scratch”, he says.
Owing to a 2008 law passed by Congress, the White House Office of Science and Technology Policy has until 15 October to decide which agency will be responsible for protecting the planet from an asteroid strike. Members of the task force say NASA expects to be given part or all of that responsibility. To meet it, the panel discussed the creation of a Planetary Protection Coordination Office (PPCO) within NASA, with an annual budget of $250 million”$300 million. It would detect and track asteroids ” and develop a capability to deflect them. “You want to use a proven capability when you’re talking about an actual threat,” says Rusty Schweickart, a former astronaut and the other panel co-chair.
The PPCO would also challenge other countries to fund defence against asteroids, perhaps through the United Nations. Canada already plans to launch the NEO Survey Satellite in 2011, and Germany’s AsteroidFinder is slated for launch in 2012, but neither is expected to come close to the NEO-logging goal by 2020.
Shapiro stresses that it is unclear whether Congress will give further funds to planetary protection, noting that if it doesn’t, there is a risk of the money being taken away from space science. Yet without better detection and tracking there will inevitably be uncertainty about asteroid positions in the future ” and even greater expense if the uncertainty leads to unnecessary efforts to thwart an apparent pressing threat. 

From: http://www.itwire.com/science-news/space/41752-nasa-considers-asteroid-impact-with-earth

The Nature News article concludes with: “… [I]t is unclear whether Congress will give further funds to planetary protection, noting that if it doesn't, there is a risk of the money being taken away from space science. Yet without better detection and tracking there will inevitably be uncertainty about asteroid positions in the future — and even greater expense if the uncertainty leads to unnecessary efforts to thwart an apparent pressing threat.”

For more information on the detection, tracking, and deflection of near-Earth objects, please read the following.

In 2007 NASA presented this report (pdf file) to the U.S. Congress entitled “Near-Earth Object Survey and Deflection Analysis of Alternatives.”

NASA calls possible asteroids that could possibly impact Earth "Potentially Hazardous Asteroids (PHAs)."

They are defined "... based on parameters that measure the asteroid's potential to make threatening close approaches to the Earth. Specifically, all asteroids with an Earth Minimum Orbit Intersection Distance (MOID) of 0.05 AU or less and an absolute magnitude (H) of 22.0 or less are considered PHAs."

One AU (astronomical unit) is the average distance between Earth and the Sun -- about 93 million miles (150 million kilometers).

And, "In other words, asteroids that can't get any closer to the Earth (i.e. MOID) than 0.05 AU (roughly 7,480,000 km or 4,650,000 mi) or are smaller than about 150 m (500 ft) in diameter (i.e. H = 22.0 with assumed albedo of 13%) are not considered PHAs."

NASA states, "There are currently 1144 known PHAs."

And, "This "potential'' to make close Earth approaches does not mean a PHA will impact the Earth. It only means there is a possibility for such a threat. By monitoring these PHAs and updating their orbits as new observations become available, we can better predict the close-approach statistics and thus their Earth-impact threat."

Learn more about PHAs at NASA's "What is a PHA?"

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