July 11, 2011 - Trifid Triple Treat

Trifid Triple Treat The massive star factory known as the Trifid Nebula, which gets its name from the dark dust bands that trisect its glowing heart, is a rare combination of three nebulae types. The bluish patch to the upper left is a reflection nebula, where dusty gas scatters the light from nearby Trifid-born stars. Below, the pink-reddish area is typical of an emission nebula, caused by the gas at the Trifid’s core being heated by hundreds of scorching young stars until it glows in the red light typical of hydrogen. The gas and dust that crisscross the Trifid Nebula make up the third kind of nebula in this cosmic cloud, known as dark nebulae because of their light-obscuring effects. The field of view of the image, taken at the European Southern Observatory’s La Silla site in northern Chile, is half the width of the full Moon.

Image credit: European Southern Observatory

Weekly Calendar

July 11-17, 2011

Holidays - Sky Events - Space History

Moon phase Monday 11

1962: NASA selects lunar orbit rendezvous method for lunar landings
1969: X-24A lifting body rolled out for first time
1979: Skylab reenters atmosphere

Moon phase Tuesday 12

1966: First glide test of M2-F2 lifting body
2000: Zvezda Service Module launched to ISS
2001: STS-104 Atlantis launched

Moon phase Wednesday 13

1995: STS-70 Discovery launched

Moon phase Thursday 14

1965: Mariner 4 completes first successful flyby of Mars
1967: Surveyor 4 launched

Moon phase Friday 15

Full Moon 2:40 AM ET

1975: Apollo-Soyuz Test Project (Apollo 18) launched, last Apollo mission
2004: Aura satellite launched
2009: STS-127 Endeavour launched

Moon phase Saturday 16

1969: Apollo 11 launched
1994: First fragment of Comet Shoemaker-Levy 9 impacts Jupiter
2011: Dawn spacecraft enters orbit around Vesta

Moon phase Sunday 17

1850: John Adams Whipple takes first stellar photograph (Vega)
1970: Final HL-10 lifting body flight
1975: Apollo-Soyuz dock in orbit
1984: Soyuz T-12 launched, 100th human space flight

Suggestions for new history dates or better links? Corrections for errors on this page? Please e-mail me.