ABOUT FACTS NET Air/Space Craft

Well we did it, we hit a bullet with another bullet. So why did we go to all this bother and expense? If asked, NASA would tell you that we wanted to know what the solar system was made up of in the beginning, when it was first formed and thus know what comets were made of. They have stated many times that comets were formed when the solar system was, and that the comets are mostly unchanged. There may be other reasons for this test, such as the accuracy of a speeding missile but whatever the reason, we have performed a historic first. Just to give you a little background on Tempel 1, it was discovered on April 3, 1867 by Ernst Wihelm Leberecht Tempel in Marseilles France. It wasn't an accidental discovery, he was searching for comets and the tradition is that who ever finds an undiscovered comet gets to name it. This tradition still exists today.

NASA's Deep Impact spacecraft as technicians work on the vehicle

I watched the actual NASA broadcast of this event on the Internet. This is the first time I have ever seen a live telecast on the Internet. It was very interesting but would not have been a big hit on tv. The reason for this is there were many silent spaces where the camera just watched different engineers doing their jobs or talking to other engineers or even drinking coffee. The engineers all seemed to be dressed in either red or blue shirts. I was watching the Jet Propulsion Laboratory a NASA division. Three different rocket motor burns had to be made to correct the path so that the impactor would crash in the intended spot on the comet. The last correction was for a change in the intended crash area. It was thought that the flyby space craft could get a better photo if the probe crashed closer to the bottom of the comet. As each successive burn took place the NASA people applauded. Tensions were high after the last burn then a voice came over the speaker and it stated that the rate of error for the final burn was only 0.23%. Everyone clapped again. I guess this was a very good thing. I don't have any idea what the acceptable margin of error was in this case. At exactly 1:52 am, Eastern Standard Time and 10:52 pm, Pacific Time, the probe crashed into Tempel 1.

This mission was not to be taken lightly It took six years from start to finish. The planning for the mission started in November 1999 and finished in May 2001. In December 2004 the launch took place. The actual flight time was from December 2004 to July 2005. The flyby craft carried an impactor craft that was powered by batteries. It needed to be able to fly on its own for one day. The impactor then took photos of the comet as it headed toward the comet for the impact which would destroy it, but cause material from inside the comet to eject into space. This material would be studied by the flyby craft to determine what the comet was made of. Scientists are eager to learn whether comets exhaust their supply of gas and dust to space or seal it into their interiors. The flyby craft examines the debris that is ejected from the comet and the impact area on the comet itself. The team that handled this mission included over 250 people.

The impact generated was equal to about 4.5 tons of TNT. Not much is known about comets or their interiors to date. Hopefully, this will change after this successful mission. So how do NASA scientists describe this impact? One said it was like standing in the middle of a road and a huge semi tractor trailer coming down out of the sky at 23,000 mph. The area where the comet was hit was about 80,000,000 miles from Earth. The price tag for this mission is about 330,000,000 dollars. This is less that buying a new stealth bomber, a lot less.