September 11, 2017 - Spacecraft Sacrifice
Spacecraft Sacrifice After more than thirteen years spent orbiting Saturn, the Cassini spacecraft will end its historic mission this week with a controlled plunge into the ringed planet’s atmosphere. This fiery end is necessary because once Cassini’s maneuvering fuel runs out, it might end up crashing into—and inadvertently contaminating with earthly microbes—Enceladus or Titan, two Saturnian moons that are believed to have environments suitable for life. This cutaway illustration of Enceladus depicts possible hydrothermal activity that may be taking place on and under the sea floor of the moon’s ocean, which is trapped beneath a shell of ice. Europa is a prime target for future searches for life in the solar system because it has abundant sources of water, complex organic molecules, and a source of heat.
Image credit: NASA / JPL-Caltech
Weekly Calendar
September 11-17, 2017
Holidays - Sky Events - Space History
Monday 11
1877: James Jeans born
1985: International Cometary Explorer satellite probes Comet Giacobini-Zinner (first comet flyby)
1997: Mars Global Surveyor arrives at Mars
Tuesday 12
Mercury at greatest elongation (18° W)
Aldebaran 0.4° south of Moon
1959: Luna 2 launched
1966: Gemini XI launched
1970: Luna 16 launched
1991: STS-48 Discovery launched
1992: STS-47 Endeavour launched
1993: STS-51 Discovery launched
2017: Soyuz MS-06 launched carrying ISS Expedition 53/54 crew
Wednesday 13
Last Qtr Moon 2:25 AM ET
Moon at perigee
1977: Second glide test of Space Shuttle Enterprise
1978: Venera 12 launched
Thursday 14
1966: Gemini XI, docked with Agena booster rocket, reaches 850-mile-high orbit
Friday 15
1965: “Lost in Space” premieres
1968: Zond 5 launched, first circumlunar spaceflight with living creatures (tortoises)
2016: Tiangong-2 space station launched
2017: Cassini mission ends with planned entry into Saturn’s atmosphere
Saturday 16
Mercury 0.06° north of Mars
1848: First observation of Hyperion, moon of Saturn
1996: STS-79 Atlantis launched
Sunday 17
Venus 0.5° north of Moon
1789: William Herschel discovers Mimas
1857: Konstantin Tsiolkovsky born
1930: Ed Mitchell born
1959: First powered flight of X-15
1976: First rollout of space shuttle Enterprise