Friday, December 21, 2007

Asteroid Misses Earth, Threatens Mars

Trajectory of Asteroid 2007 WD5 on December 21, 2007.
The asteroid passed within 7.5 million kilometers of Earth on November 1, 2007, and is now halfway to Mars, moving at 45,000 kilometers per hour. As of December 21 its chances of striking Mars are 1 in 75. Credit: NASA/JPL

Astronomers in NASA’s Near Earth Object (NEO) monitoring program are tracking the trajectory of an asteroid estimated to be 50 meter (160 feet) wide that is expected to cross Mars' orbital path early next year. Observations provided by the astronomers and analyzed by NASA's NEO Office at the Jet Propulsion Laboratory in Pasadena, Calif., indicate the object is likely to pass within 50,000 kilometers (30,000 miles) of Mars at 5:55 a.m. EST (10:55 UT) on Jan. 30, 2008. There is also a 1 in 75 probability that the asteroid will slam into the planet at that time.

Designated 2007 WD5, the asteroid was discovered on November 20 by NASA-funded observers searching for possible Earth-impactors. At that time of its detection the asteroid had already made its closest pass of the Earth, closing to within 7.5 million kilometers (4.7 million miles) on November 1, and was moving towards Mars. The original detection was made using the 1.5 meter telescope on Mount Lemmon, near Tucson, Arizona, and was followed up with observations at Kitt Peak, Arizona, and the Magdalena Ridge Observatory in New Mexico. Taken together, the observations indicated that although Earth was safe from 2007 WD5, our smaller neighbor Mars may not be.

"Right now asteroid 2007 WD5 is about half-way between the Earth and Mars and closing the distance at a speed of about 27,900 miles per hour," said Don Yeomans, manager of the Near Earth Object Office at JPL. "Over the next five weeks, we hope to gather more information from observatories so we can further refine the asteroid's trajectory."

If the asteroid does indeed strike Mars, it will impact somewhere in an 800 kilometer (500 mile) wide band that crosses the Martian equator. The southernmost boundary of this band lies slightly to the north of the region explored by the rover Opportunity. Though close, however, the rover is clearly outside the zone of possible impact.

"We estimate such impacts occur on Mars every thousand years or so," said Steve Chesley, a scientist at JPL. "If 2007 WD5 were to thump Mars on Jan. 30, we calculate it would hit at about 50,000 kilometers per hour (30,000 miles per hour) and might create a crater more than half-a-mile wide."

Such a collision could release about three megatons of energy. Scientists believe an event of comparable magnitude occurred here on Earth in 1908 in Tunguska, Siberia, but no crater was created. The object was disintegrated by Earth's thicker atmosphere before it hit the ground, although the air blast devastated a large area of unpopulated forest.

The Chicxulub Impact
An artist's depiction of the Chicxulub impact, 65 million years ago, which brought about a mass extinction of life on Earth. The diameter of the Chicxulub impactor was 200 times that of 2007 WD5, and its mass thousands of times greater. Credit: Don Davis

Though the chances of a collision between Mars and 2007 WD5 are slim, planetary scientists are nevertheless hoping that the asteroid will thread the needle and strike the red planet. If this were to happen, it would be the first time that scientists would get a chance to observe the impact of an asteroid on a terrestrial planet such as Mars or Earth. This is especially significant, because current theories suggest that bombardment by space rocks played a key role in our own planet’s evolution, from the introduction of water to the demise of the dinosaurs. And while scientists do possess effective computer models of the dynamics of an asteroid impact, there is no substitute to the actual observation of a natural event.

In 1994 comet Shoemaker-Levy 9 struck Jupiter, providing scientists with their only close-up view of a celestial collision. But Jupiter is a gas giant, and the dynamics of impact are very different than they are on a rocky planet such as Mars.


Gerald said...

Rulers who want to unleash war know very well that they must procure or invent a first victim.
– Elias Canetti

Gerald said...

December 22, 2007
It's Common Sense, Not Pacifism

by Charley Reese
I should clarify something during this season when everyone hopes for peace and good will: I am not a pacifist.

If war is forced upon us, we have no choice but to fight it. Ernest Hemingway said it well when he observed that there are several things worse than war, and they all come with defeat.

I have opposed and still oppose the war in Iraq because, knowing something about the Middle East, I knew it would be futile. I knew we weren't threatened by Iraq. I knew that the war would be a war of aggression on our part. I knew that no clear-cut victory would be possible.

Even though there has been some diminution in violence, the fundamental political problem remains. The Sunnis, the Shi'ites and the Kurds are not fond of each other. For a long time, the Shi'ites and the Kurds suffered under Saddam Hussein's primarily Sunni regime. Now that the Shi'ites and the Kurds are in control, they are not going to be easily reconciled. Furthermore, the Kurds don't especially like Arabs and want an independent country. The Turks don't especially like the Kurds and will react violently to any move on the part of the Kurds to declare independence.

So, the U.S. forces in the country have a wolf by the ear. We can keep the level of violence reasonably contained as long as we stay there, but neither the armed forces nor the U.S. budget can afford to stay there indefinitely. And to leave, we have to let go of the wolf.

The present peace in the Anbar province came about because the al-Qaeda fighters went too far and the Sunni sheiks decided to kill them. We, opportunistically, said, "Hey, as long as you're killing al-Qaeda instead of us, we will give you guns and money." Now the Marines in Anbar are enjoying Arab hospitality, which I fear they are mistaking for friendship.

I don't know how things will play out. As long as the cowardly Congress continues to fund the war, the troops will be stuck there. Don't look for any victory parades or celebrations. Bombs and bullets will stay on the menu probably as long as we are there and afterward, too, until some new Iraqi strongman takes control.

As for Afghanistan, where the situation is deteriorating, Americans should be clear about what we did there. The Taliban won the civil war by driving the northern warlords out of Kabul. We hired the warlords to fight the Taliban, bribing them with cash and air support. Afghanistan is now run by the warlords, and they are turning it into a narco-state. At the same time, we failed to catch or kill Osama bin Laden, who was the only person in Afghanistan or Iraq who had attacked us.

Now the U.S. has dragged NATO into the fight, but I don't think the Europeans will stick. What is the point of a European getting himself killed in Afghanistan? Or an American, for that matter? There is nothing in Afghanistan except fields of opium and men with rifles.

We are overextended, both militarily and financially. That's just a sad truth. Our economy is teetering on the edge of a recession or worse. Our so-called diplomacy in the Middle East is getting less than zero results. We are crazy to try to stay there. The age of colonialism is over.

We should go to war only in self-defense. I don't believe the American people wish to adopt Iraq and Afghanistan as permanent wards of the taxpayers. I don't believe they want to keep burying sons and daughters whose deaths don't make America safer. That's not pacifism. It's common sense.

Gerald said...

Nothing Can Morally Justify the Invasion of Iraq

Neo-con supporters of the U.S. government's war of aggression against Iraq are undoubtedly holding their collective breath in the hope that U.S. military forces have finally smashed any further violent opposition to their conquest of Iraq. The attitude would then be, "You see, this shows that we were right after all to invade and occupy Iraq and kill and maim hundreds of thousands of Iraqi people."

Meanwhile, the Associated Press is reporting that U.S. soldiers have found mass graves next to a torture center north of Baghdad. In the torture center, chains were attached to blood-spattered walls while a metal bed was attached to an electrical shock system.

Hey, who knows? Maybe the torture center prevented a ticking time bomb from going off? And who's to say that chains, blood-spattered walls, metal beds, and an electrical shock system really constitute torture? Doesn't torture depend on each person's subjective determination of the term?

By the way, wasn't there torture in Iraq under Saddam Hussein? I wonder if his justifications for torture were different from those employed by those torturing in Iraq today. I wonder if they were different than those employed by current U.S. torturers.

As Rosa Brooks writes in the Los Angeles Times today, Baghdad has now been divided into "cleansed" neighborhoods, in which Sunnis occupy some areas and Shiites occupy others. The U.S. military is helping to keep the neighborhoods free of violence by constructing walls that separate the respective neighborhoods. What an interesting way for the Pentagon to rebuild a peaceful society that it has destroyed with its invasion.

Meanwhile, hundreds of thousands of Iraqis have fled the country, mostly to neighboring countries given that the U.S. government refuses to let them emigrate to the United States, despite one of the U.S. government's claims (in addition to the WMD one) that it invaded Iraq out of love for the Iraqi people. Hey, what better way to reduce the death toll than by reducing the country's population?

And if things weren't crazy enough, we now learn that the U.S. government is helping Turkey to attack Iraqi Kurds in the northern part of the country. Can't you just hear U.S. officials exclaim when some Iraqi survivor of those attacks retaliates with a terrorist attack against the U.S.: "We're innocent! We're innocent! We haven't done anything to provoke this! They hate us for our freedom and values! God bless America!"

No rational person can deny that Iraq never had any connection whatsoever to the 9/11 attacks, especially given that none of the 9/11 attackers were even from Iraq. Yet, countless Iraqi people are now dead or maimed and their entire country is destroyed. One might easily say that Iraq is the federal massacre of Waco magnified a million-fold. The whole situation in Iraq brings to mind the famous dictum of Tacitus: "They made a desert and called it peace."

Nothing, not even "peace" in Iraq, will ever be able to morally justify a war of aggression against a nation whose people were totally innocent of the 9/11 attacks. Nothing, not even some warped definition of "terrorist," will ever be able to morally justify killing Iraqis who were doing nothing more than trying to oust their country of an illegal invader who had invaded with a thirst for vengeance and regime change relying on fake and false rationales for its invasion. Nothing will ever be able to morally justify the killing of even one single Iraqi, much less hundreds of thousands of them, given that neither the Iraqi people nor their government ever attacked the United States.

Jacob Hornberger is founder and president of The Future of Freedom Foundation.

Gerald said...

Pakistan is next to be attacked by Nazi America

Gerald said...

Defense Secretary Robert M. Gates said today that Al Qaeda insurgents who were launching attacks in Afghanistan have now shifted their emphasis to Pakistan, increasing the threat in that nation.

Gerald said...


capt said...

Non-stop, never-ending, perpetual war for non-stop, never-ending, perpetual war profits.

Carey said...

Gosh, I have to find time to come here more often. I wish I did have more time, but I've got to keep pushin'.

Your posts are incredible Capt. Really, you've got quite a fascinating array of interests.

That asteroid, God!