Re: [meteorite-list] DoD To Engage Decaying Satellite
There is just something not right about the assumptions in this press release; take it from an old amateur rocket man. Hydrazine boils at 114 Celsius. If the tank containing it re-enters, it is almost certain to heat up and boil the material, overpressure the tank and explode long before reaching the ground. If a fissure develops in the tank, and hydrazine is exposed to the oxygen in the air, even in the stratosphere, it will blow up at just above body temperature, 37 Celsius. The chances of any hydrazine reaching the ground, and spilling out after impact, is zero I would think. It's not really a credible danger. There may be other perfectly valid reasons why the DoD might want to destroy this satellite. Target practice is one. And there may be perfectly good reasons why they might not want souvenir hunters picking over the wreckage if it lands. It's a top-secret spy satellite, after all. Photos of the wreckage could be used to understand surveillance limitations and abilities. This is something the North Koreans probably would like to know. These are very good reasons for asking the public to stay clear. But hydrazine after re-entry? No, I don't think so. I realize I'm a bit controversial on this. So if any of you folks want to point out why I could be wrong, please do. But I think that hydrazine simply would not survive re-entry. Francis Graham --- Ron Baalke [EMAIL PROTECTED] wrote: Public Affairs U.S. Department of Defense Office of the Assistant Secretary of Defense Washington, D.C. Media contact: +1 (703) 697-5131/697-5132 IMMEDIATE RELEASE: February 14, 2008 No. 0125-08 DoD To Engage Decaying Satellite An uncontrollable U.S. experimental satellite which was launched in December 2006 is expected to reenter Earth's atmosphere between the end of February and early March. Because the satellite was never operational, analysis indicate that approximately 2,500 pounds (1134 kgs) of satellite mass will survive reentry, including 1,000 pounds (453 kgs) of propellant fuel (hydrazine), a hazardous material. Although the chances of an impact in a populated area are small, the potential consequences would be of enough concern to consider mitigating actions. Therefore, the President has decided to take action to mitigate the risk to human lives by engaging the non-functioning satellite. Because our missile defense system is not designed to engage satellites, extraordinary measures have been taken to temporarily modify three sea-based tactical missiles and three ships to carry out the engagement. Based on modeling and analysis, our officials have high confidence that the engagement will be successful. As for when this engagement will occur, we will determine the optimal time, location, and geometry for a successful engagement based on a number of factors. As the satellite's path continues to decay, there will be a window of opportunity between late February and early March to conduct this engagement. The decision to engage the satellite has to be made before a precise prediction of impact location is available. Contact with hydrazine is hazardous. Direct contact with skin or eyes, ingestion or inhalations from hydrazine released from the tank upon impact could result in immediate danger. If this operation is successful, the hydrazine will then no longer pose a risk to humans. The U.S. government has been and continues to track and monitor this satellite. Various government agencies are planning for the reentry of the satellite. In the event the engagement is not successful, all appropriate elements of the U.S. Government are working together to explore options to mitigate the danger to humans and to ensure that all parties are properly prepared to respond. In the unlikely event satellite pieces land in a populated area, people are strongly advised to avoid the impact area until trained hazardous materials (HAZMAT) teams are able to properly dispose of any remaining hydrazine. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] DoD To Engage Decaying Satellite
I think you are largely correct that the safety of people on the ground is a minor component of the decision to fragment this satellite. That said, however, the behavior of decaying space debris isn't all that different from the behavior of a meteor. Just as the interior of a meteorite isn't significantly heated during its passage through the atmosphere, the interior of debris need not reach high temperatures during decay. We know nothing about the location of the fuel tank in this satellite, but if it's buried inside, I think it is at least possible it could survive to the ground intact. I recall that nematodes for biological experiments aboard the Columbia shuttle survived reentry. Chris * Chris L Peterson Cloudbait Observatory http://www.cloudbait.com - Original Message - From: Francis Graham [EMAIL PROTECTED] To: meteorite-list@meteoritecentral.com Sent: Saturday, February 16, 2008 1:51 PM Subject: Re: [meteorite-list] DoD To Engage Decaying Satellite There is just something not right about the assumptions in this press release; take it from an old amateur rocket man. Hydrazine boils at 114 Celsius. If the tank containing it re-enters, it is almost certain to heat up and boil the material, overpressure the tank and explode long before reaching the ground. If a fissure develops in the tank, and hydrazine is exposed to the oxygen in the air, even in the stratosphere, it will blow up at just above body temperature, 37 Celsius. The chances of any hydrazine reaching the ground, and spilling out after impact, is zero I would think. It's not really a credible danger. There may be other perfectly valid reasons why the DoD might want to destroy this satellite. Target practice is one. And there may be perfectly good reasons why they might not want souvenir hunters picking over the wreckage if it lands. It's a top-secret spy satellite, after all. Photos of the wreckage could be used to understand surveillance limitations and abilities. This is something the North Koreans probably would like to know. These are very good reasons for asking the public to stay clear. But hydrazine after re-entry? No, I don't think so. I realize I'm a bit controversial on this. So if any of you folks want to point out why I could be wrong, please do. But I think that hydrazine simply would not survive re-entry. Francis Graham __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] DoD To Engage Decaying Satellite
Hi all, Someone (or maybe one of the articles) said that the missle didn't have a war-head so there wouldn't be an explosion, but what if the missle hits the hydrazine tank? Would that cause an explosion? Regards, Bob -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Francis Graham Sent: Saturday, February 16, 2008 1:51 PM To: meteorite-list@meteoritecentral.com Subject: Re: [meteorite-list] DoD To Engage Decaying Satellite There is just something not right about the assumptions in this press release; take it from an old amateur rocket man. Hydrazine boils at 114 Celsius. If the tank containing it re-enters, it is almost certain to heat up and boil the material, overpressure the tank and explode long before reaching the ground. If a fissure develops in the tank, and hydrazine is exposed to the oxygen in the air, even in the stratosphere, it will blow up at just above body temperature, 37 Celsius. The chances of any hydrazine reaching the ground, and spilling out after impact, is zero I would think. It's not really a credible danger. There may be other perfectly valid reasons why the DoD might want to destroy this satellite. Target practice is one. And there may be perfectly good reasons why they might not want souvenir hunters picking over the wreckage if it lands. It's a top-secret spy satellite, after all. Photos of the wreckage could be used to understand surveillance limitations and abilities. This is something the North Koreans probably would like to know. These are very good reasons for asking the public to stay clear. But hydrazine after re-entry? No, I don't think so. I realize I'm a bit controversial on this. So if any of you folks want to point out why I could be wrong, please do. But I think that hydrazine simply would not survive re-entry. Francis Graham --- Ron Baalke [EMAIL PROTECTED] wrote: Public Affairs U.S. Department of Defense Office of the Assistant Secretary of Defense Washington, D.C. Media contact: +1 (703) 697-5131/697-5132 IMMEDIATE RELEASE: February 14, 2008 No. 0125-08 DoD To Engage Decaying Satellite An uncontrollable U.S. experimental satellite which was launched in December 2006 is expected to reenter Earth's atmosphere between the end of February and early March. Because the satellite was never operational, analysis indicate that approximately 2,500 pounds (1134 kgs) of satellite mass will survive reentry, including 1,000 pounds (453 kgs) of propellant fuel (hydrazine), a hazardous material. Although the chances of an impact in a populated area are small, the potential consequences would be of enough concern to consider mitigating actions. Therefore, the President has decided to take action to mitigate the risk to human lives by engaging the non-functioning satellite. Because our missile defense system is not designed to engage satellites, extraordinary measures have been taken to temporarily modify three sea-based tactical missiles and three ships to carry out the engagement. Based on modeling and analysis, our officials have high confidence that the engagement will be successful. As for when this engagement will occur, we will determine the optimal time, location, and geometry for a successful engagement based on a number of factors. As the satellite's path continues to decay, there will be a window of opportunity between late February and early March to conduct this engagement. The decision to engage the satellite has to be made before a precise prediction of impact location is available. Contact with hydrazine is hazardous. Direct contact with skin or eyes, ingestion or inhalations from hydrazine released from the tank upon impact could result in immediate danger. If this operation is successful, the hydrazine will then no longer pose a risk to humans. The U.S. government has been and continues to track and monitor this satellite. Various government agencies are planning for the reentry of the satellite. In the event the engagement is not successful, all appropriate elements of the U.S. Government are working together to explore options to mitigate the danger to humans and to ensure that all parties are properly prepared to respond. In the unlikely event satellite pieces land in a populated area, people are strongly advised to avoid the impact area until trained hazardous materials (HAZMAT) teams are able to properly dispose of any remaining hydrazine. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
[meteorite-list] DoD To Engage Decaying Satellite
Public Affairs U.S. Department of Defense Office of the Assistant Secretary of Defense Washington, D.C. Media contact: +1 (703) 697-5131/697-5132 IMMEDIATE RELEASE: February 14, 2008 No. 0125-08 DoD To Engage Decaying Satellite An uncontrollable U.S. experimental satellite which was launched in December 2006 is expected to reenter Earth's atmosphere between the end of February and early March. Because the satellite was never operational, analysis indicate that approximately 2,500 pounds (1134 kgs) of satellite mass will survive reentry, including 1,000 pounds (453 kgs) of propellant fuel (hydrazine), a hazardous material. Although the chances of an impact in a populated area are small, the potential consequences would be of enough concern to consider mitigating actions. Therefore, the President has decided to take action to mitigate the risk to human lives by engaging the non-functioning satellite. Because our missile defense system is not designed to engage satellites, extraordinary measures have been taken to temporarily modify three sea-based tactical missiles and three ships to carry out the engagement. Based on modeling and analysis, our officials have high confidence that the engagement will be successful. As for when this engagement will occur, we will determine the optimal time, location, and geometry for a successful engagement based on a number of factors. As the satellite's path continues to decay, there will be a window of opportunity between late February and early March to conduct this engagement. The decision to engage the satellite has to be made before a precise prediction of impact location is available. Contact with hydrazine is hazardous. Direct contact with skin or eyes, ingestion or inhalations from hydrazine released from the tank upon impact could result in immediate danger. If this operation is successful, the hydrazine will then no longer pose a risk to humans. The U.S. government has been and continues to track and monitor this satellite. Various government agencies are planning for the reentry of the satellite. In the event the engagement is not successful, all appropriate elements of the U.S. Government are working together to explore options to mitigate the danger to humans and to ensure that all parties are properly prepared to respond. In the unlikely event satellite pieces land in a populated area, people are strongly advised to avoid the impact area until trained hazardous materials (HAZMAT) teams are able to properly dispose of any remaining hydrazine. __ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
