July 29, 2019 - Revisiting Mercury

Revisiting Mercury  The closest planet to the Sun was also the least studied planet in the inner solar system. By the end of the Twentieth Century, only a single space mission, Mariner 10, had successfully visited Mercury. Its three flybys of Mercury in 1974 and 1975 revealed a battered and geologically complex world, and left scientists eager to learn more. Fifteen years ago this week, NASA launched the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft (MESSENGER), which flew past Mercury three times before finally entering orbit around the planet in 2011, the first spacecraft to do so. MESSENGER orbited Mercury until 2015. This MESSENGER false-color image looks northwest over the Caloris Basin. The 41 km (25 mi) diameter impact crater, Apollodorus, is at bottom.

Image credit: NASA / JHU-APL / Carnegie Institution of Washington / GSFC

Weekly Calendar

July 29 - August 4, 2019

Holidays - Sky Events - Space History

 

Monday 29

Delta Aquarid meteor shower

1985: STS-51F Challenger launched

Tuesday 30

1965: SA-10 launched, last Saturn 1 vehicle
1971: Apollo 15 lands on Moon

Wednesday 31

Mercury appears stationary
New Moon 11:12 PM ET

1969: Mariner 6 flies by Mars
1971: First vehicle driven on Moon by Apollo 15 astronauts Scott & Irwin
1992: STS-46 Atlantis launched
1999: Lunar Prospector mission ends

Thursday 1

1818: Maria Mitchell born
1967: Lunar Orbiter V launched
1968: Saturn V production ends
1973: First X-24B lifting body glide test

Friday 2

Moon at perigee

1971: Apollo 15 lunar module Falcon leaves Moon in first televised lunar liftoff
1991: STS-43 Atlantis launched

Saturday 3

2004: MESSENGER spacecraft launched to Mercury
2005: First in-flight space shuttle repair

Sunday 4

1967: NASA announces sixth astronaut class
1984: First Ariane 3 launched
2007: Phoenix Mars Lander launched