NASA loves to plan space missions in such a way that their significant milestones fall on July 4th. For example, on July 4, 1997, the Mars Pathfinder station with the Sojourner rover landed on Mars, and on July 4, 2016, the Juno device arrived at Jupiter. But still the most spectacular was the celebration on July 4, 2005. It was on this day that a 370-kilogram striker launched by the Deep Impact station struck Comet 9P / Tempel.
The purpose of the bombing was to study the interior of the comet. Deep Impact tools had to analyze the substance ejected upon impact. Before the mission began, opinions differed as to how the bombing would end. But the result exceeded all expectations: the collision caused a massive release of cometary matter. According to various estimates, 9P / Tempel lost about 5 thousand tons of water and from 10 to 25 thousand tons of dust.
Analysis of the ejected matter showed that the comet consists of water ice, volatile fractions, carbonates, polynuclear aromatic hydrocarbons, sulfides and other components.
After the collision, an impact crater remained on the surface of 9P / Tempel. The quality of the Deep Impact images did not allow us to accurately estimate its size, so NASA decided to send the Stardust apparatus to the comet. On February 15, 2011, he passed 200 kilometers from 9P / Tempel. The station's cameras captured the 150-meter crater left by Deep Impact.