Tag Archive | "asteroids"

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Asteroids & Meteors Are Still Dangerous

Posted on 07 January 2016 by Jerry

Our planet Earth is being bombarded all the time by asteroids or meteorites. Fortunately most of them do not hit the Earth, passing harmlessly by us in space. Even when they come in contact with the Earth’s atmosphere, most of them burn up before they hit the ground. Many of them are large enough to destroy a city. Some we see ahead of time. Some surprise us with no warning.

As an example, NASA shows approximately 90 near earth objects that will come toward Earth at a distance closer than our distance to the moon (~384,000 kilometers). These are only the asteroids or meteors that will pass us between January 1, 2016 and March 1, 2016 or just two months. At the larger end these range from 17 that are larger than 250 meters in diameter to over 2.1 kilometers. As a measure of scale, 92 meters equals ~100 yards or a football field.

February 15, 2013 was a historic day. In the same day we were visited by a flyby asteroid (DA14) we anticipated in 2012 and one not anticipated. The flyby came within 17,000 miles of our planet. Unfortunately, the average “house-sized”, unanticipated asteroid entered the Earth’s atmosphere and exploded just 12 miles up in the air. This was over the city of Chelyabinsk in Russia. This explosion injured 1,000+ people mainly from flying glass.  Nova claims the explosion was 20 to 30 times that of the bomb dropped on Hiroshima, Japan.

But how big can asteroids or meteors be? To answer that question we could go back to the largest known impact ever discovered on the Earth’s surface. We are talking about the Chicxulub Crater in the Gulf of Mexico. This was the asteroid/meteor given credit for wiping out the dinosaurs and ushering in mammals as the new dominant life form. This asteroid/meteor was estimated to be 10 km in diameter. It ended the Cretaceous period, about 65.5 million years ago.

There are 26 known asteroids larger than 200 kilometers in diameter. The largest asteroid is Ceres. It is 974 km in diameter. The next three are 2 Pallas, 4 Vesta and 10 Hygiea. They are all between 400 and 525 km in diameter. All of these are much larger than the Chicxulub asteroid.

Chicxulub was an extinction event. Its energy was more than a billion times the explosive power of the Nagasaki and Hiroshima atom bombs. Earlier dating methods place the asteroid at 300,000 years before or 180,000 years after the end-cretaceous mass extinction. Newer, more precise dating methods however put the asteroid at no more that 33,000 years from the end of the K-T (Cretaceous-Tertiary) extinction event. For purposes of dating 33,000 years is simultaneous and represents the most accurate timing humans have yet to devise.

Recent research has shown that there was a basalt volcanic eruption on the other side of the Earth, the Deccan Traps in India that was influenced by the asteroid’s impact. Research on the asteroid points to shock waves created by the asteroid that reached the volcanic eruption on the other side of the world and may have accelerated the flows which only increased the deaths of dinosaurs during this period.

Unfortunately we are not paying a lot of money to detect new asteroids.   An article which appeared on space.com in 2013 one month after the flyby and explosion over Chelyabinsk describes the problem we face.   Roughly one month after the asteroid officials on capital hill asked NASA and the military what they were doing to combat the problem of unknown asteroids.

The article stated, “Rep. Lamar Smith (R-Texas), chairman of the Science, Space and Technology Committee, said it was not reassuring to learn that NASA has so far detected only about 10 percent of the near-Earth objects that are wider than 459 feet (140 meters) across. Holdren (Science advisor to Obama) estimated there may be hundreds of thousands of such objects within one-third the distance from Earth to the sun that remain unknown.”

The article continued, “In 2005, Congress directed NASA to detect, track and characterize 90 percent of these space rocks – those near-Earth asteroids larger than 459 feet (140 m).” Charles Bolden, NASA’s chief is quoted, as saying there was no way the space agency would meet its deadline. He reminded Congress they has not appropriated any money and said, “Our estimate right now is at the present budget levels it will be 2030 before we’re able to reach the 90 percent level as prescribed by Congress.”

The University of Hawaii and its Institute for Astronomy at Manoa founded the Pan-STARRS project that searches for large “killer asteroids”. While the Pan-STARRS project takes a month to complete one sweep of the sky in a deep but narrow survey the recently funded ATLAS will use 8 smaller 20-inch telescopes to look at the visible sky twice a night. The ATLAS (Asteroid Terrestrial-impact Last Alert System) is a result of a $5-million grant from NASA.

ATLAS is designed to offer a one-week warning of an impact by a 50-yard asteroid or “city killer.” It will also offer three weeks of warning of a 150 yard-diameter “county killer”.

Also the non-profit B612 Foundation has been started and is raising money to create an advance warning system for Earth to ward against the threat of a sizeable impact from outer space. The Nuclear Test Ban Treaty Organization put up a network of satellites around the globe that are being used by the B612 Foundation to record asteroid impacts on the planet.

This Foundation also plans to deploy a satellite, in conjunction with Ball Aerospace, that will implement an infrared survey mission which will catalogue 90% of asteroids that are 140 m (459 feet) in diameter in the our solar system. This will involve placing a satellite in a Venus-like orbit around the sun to scan the solar system for asteroids through the 6.5 years for which the program is funded.

These were the only references to funding found. Certainly elsewhere in the world are former astronauts, scientists, or academics that have used this need to fund their favorite capabilities. Only time will reveal them.

We all have seen movies about asteroids hitting the Earth. In some of them, the citizens of Earth are saved by a heroic astronaut, like Bruce Willis in Armageddon. Where are you Bruce when we need you!

It would be a tragedy if we were involved in an extinction event that ushered in another species but it might be a good thing. At least the new species would have a chance at survival considering all of the other threats that we have wrought that threaten life on the planet; all of the other threats that we have mounted only half-vast plans to correct or end.

People who have read my book should do as the book suggests. They should pick their favorite problem that humanity is wrestling with and should dedicate a significant amount of their money and effort to a solution. They should pick a calamity of their choice and focus on seeking its resolution.

Use the following links to get more information or access the original documents used for this article.

http://neo.jpl.nasa.gov/ca/

http://nineplanets.org/asteroids.html

http://motherboard.vice.com/blog/asteroids-and-meteors-brings-out-the-internets-best-theories

http://www.livescience.com/26933-chicxulub-cosmic-impact-dinosaurs.html

http://www.physicsforums.com/threads/did-k-t-extinction-event-meteor-puncture-a-hole-in-crust-at-chicxulub.622333/

http://www.sciencemag.org/content/339/6120/655.summary?sid=1cb5227b-e2db-437a-b649-d006ba8488f3

http://www.sciencemag.org/content/350/6256/76.abstract?sid=feddd730-2db4-44d9-bd12-4a4536bb0322

http://www.nature.com/nature/journal/v527/n7577/full/527172a.html

http://www.readcube.com/articles/10.1038%2F527172a

http://www.space.com/20292-asteroid-threat-earth-congress.html

http://www.space.com/19988-asteroid-detection-nasa-private-industry.html

http://www.gizmag.com/b612-foundation-asteroid-impact-sentinel-satellite/31765/

http://www.ifa.hawaii.edu/info/press-releases/ATLAS/

http://www.theregister.co.uk/2014/04/22/study_shows_dangerous_asteroid_impacts_hit_earth_every_six_months/ (access film embedded in article. Second picture frame.)

http://chicxulubcrater.org/Chicxulub-Facts.html

 

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Focused Space Colonization

Posted on 21 October 2011 by Jerry

There is a role for human colonization of space.  It is to create an insurance policy against a  catastrophe that might befall life on our planet. We should act as if the ongoing existence of life is precarious.  If we do not fall victim to global threats we have created like the ozone hole (which has now been duplicated over the North Pole if you didn’t know), climate change, nuclear weapons or synthetic biology, we are still vulnerable to the unanticipated impact of other space objects, such as asteroids and/or comets.  In addition, rising to the challenge of surmounting a hostile environment on another planetoid would give us the science to survive whatever deterioration of our environment may occur on planet Earth.

Our present space program can only be described as winding down.  In July 2011 with the launch of the space shuttle Atlantis a major part of our space exploration ended with the last mission of the space shuttle.  Capping three decades consisting of 134 missions, the shuttles were retired to go on display at various sites across the country. In turning away from the the average cost of each shuttle mission estimated at  roughly $1.5 billion per launch and the high estimates of the cost to replace the aging shuttle fleet, the administration has cancelled further missions and held out the entry of private businesses to transport astronauts and sightseers into space.  In the face of a global economic downturn, dwindling congressional support, the lack of a highly motivational objective and diminishing public support, we have been left with no impetus for future concerted manned space flight.

Of course the space shuttle is not our entire space program, while it may have been the general public’s most familiar space project.  Two of our unmanned probes are breaking ground giving us a view of places we have never been before: NASA’s Messenger spacecraft is entering orbit around Mercury while the Voyager 1 has become our most distant spacecraft from Earth and is about to leave our Solar System.

The Messenger space mission is finally coming to fruition after fifteen years.  Messenger has had to participate in six planetary flybys – one of Earth, two of Venus and three of Mercury itself.  These were necessary to insert the probe into the correct orbit at the right speed around Mercury.  Voyager 1, now 10.8 billion miles from Earth after its 33 year journey, is about to leave our Solar System.  It has entered space where the solar wind is no longer blowing particles away from our sun but rather sideways as the particles move down the tail of the comet-shaped heliosphere.  This phenomenon is the result of the solar wind pushing up against the particle matter coming from other stars at the official edge of the Solar System or heliopause.

In addition to these two unmanned probes, there is an ongoing series of inexpensive, short duration efforts to learn more about space.  One of these was the Wide-field Infrared Survey Explorer (WISE) that was designed as an infrared telescope to scan the universe looking for asteroids, comets and other cosmic objects.  The $320 million space telescope scanned the sky one and one-half times taking about 1.8 million images and spotting previously unseen objects including 15 comets and 25,000 asteroids.

As challenging and important as these efforts and projects are to various constituencies in academic or research circles, they pale in comparison to the effort and benefit to be gained by creating a self sustaining colony elsewhere in our solar system.  The peril to life on our planet is real with every new effort to identify asteroids and comets significantly multiplying our vulnerability.  It would be a mistake to underestimate the potential size or threat of a future object on a collision course with our planet.  While it is easy to talk about launching a space craft which will deflect an oncoming celestial object it is harder to do in reality and if it fails there is no fallback.

In addition the glacial pace with which we are moving on the ozone hole, climate change, nuclear disarmament, and synthetic biology clearly demonstrates we will be working for centuries to eliminate these threats.  An objective to establish a colony elsewhere should be a world-wide effort specifically partnering developed nations with underdeveloped nations to jointly undertake one or more essential efforts to make this objective a reality.

Background:  In Beyond Animal, Ego and Time, Chapter 4: Uncertainty, Probability and Life, we cite two prior meteor impacts that made a significant difference in the history of life on our planet.  The meteor crater discovered in the Wilkes Land region of East Antarctica is approximately 300 miles wide.  Scientists estimate that the size of the meteor that made this crater was 30 miles wide.  This meteor is credited by many scientists with the largest mass extinction of life in Earth’s geologic history, the Permian-Triassic extinction that set the stage for the age of the dinosaurs.  Another crater in the Yucatan peninsula in Mexico, the Chicxulub crater, is credited with the mass extinction of the dinosaurs setting the stage for the emergence of the next dominant species, mammals which of course includes Homo sapiens.

 

Use the following links for more information:

http://www.thespacereview.com/article/610/1

http://www.space.com/9305-president-obama-signs-vision-space-exploration-law.html

http://www.bbc.co.uk/news/science-environmnet-11988466

NASA’s Busload of Science, Science, www.sciencemag.org Vol 333, 1 July 2011

http://www.nasa.gov/multimedia/videogallery/index.html?collection_id=15044&media_id=113678611

 

 

 

October 6, 2011, San Francisco, Potpourri: Space Exploration/Colonization

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