June 28, 2010 - Fourth of July Blast

Fourth of July Blast Five years ago this week, NASA pulled off a celestial fireworks show unlike any Independence Day celebration in history. The Deep Impact probe, launched in January 2005, was designed to study the composition of a comet by intentionally crashing an impactor probe into the nucleus of Comet Tempel while the main spacecraft observed from a safe distance. As it approached the comet’s nucleus, the impactor took a series of images that have been compiled in this mosaic. The image resolution is highest near the impact site, between the two circular craters in the bottom half of the five-mile-high nucleus. The impact created a crater over 600 feet in diameter and 90-150 feet deep, and the explosion was witnessed not only by the Deep Impact spacecraft, but also by Earth-based telescopes.

Image credit: NASA / JPL / UMD

Weekly Calendar

June 28 - July 4, 2010

Holidays - Sky Events - Space History

Moon phase Monday 28

Mercury in superior conjunction

Moon phase Tuesday 29

1868: George Ellery Hale born
1961: Transit 4A launched, first nuclear-powered satellite
1971: Soyuz 11 crew dies during reentry

Moon phase Wednesday 30

Neptune 5° south of Moon

1908: Tunguska impact levels hundreds of miles of Siberian forest
2001: WMAP spacecraft launched

Moon phase Thursday 1

Canada Day (Canada)

Moon at apogee

1917: 100” mirror arrives at Mt. Wilson Observatory
1972: Wernher von Braun retires from NASA
1997: STS-94 Columbia launched

Moon phase Friday 2

1985: European Space Agency launches Giotto probe to study Halley’s Comet

Moon phase Saturday 3

Pallas appears stationary
Uranus 7° south of Moon
Jupiter 7° south of Moon

1935: Harrison Schmitt born

Moon phase Sunday 4

Independence Day

Last Quarter Moon 10:35 AM ET

1054: Crab Nebula supernova observed
1997: Mars Pathfinder lands on Mars
2005: Deep Impact probe collides with comet Tempel 1
: STS-121 Discovery launched

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