September 14, 2009 - Just Passing Through

Just Passing Through NASA’s third and final High Energy Astronomical Observatory (HEAO-3) was launched thirty years ago this week. HEAO-3 carried a cryogenic gamma-ray spectrometer, which functioned for about five months. A direct descendent of the HEAO-3 is the Chandra X-Ray Observatory, which also studies high-energy phenomena but at slightly longer wavelengths. When Chandra observed the colliding galaxies in the Bullet Cluster, it showed that the bullet-shaped pink lump at the bottom is the hot gas from one galaxy cluster, which passed through the hot gas from the other, larger cluster during the collision. Blue areas show where most of the mass of the clusters exists. That they are separate from the visible matter (in pink) gives credence to the existence of dark matter.

Image credit: X-ray: NASA/CXC/M.Markevitch et al; Optical: NASA/STScI; Magellan/U.Arizona/D.Clowe et al; Lensing Map: NASA/STScI; ESO WFI; Magellan/U.Arizona/D.Clowe et al.

Weekly Calendar

September 14-20, 2009

Holidays - Sky Events - Space History

Moon phase Monday 14

1966: Gemini XI, docked with Agena booster rocket, reaches 850-mile-high orbit

Moon phase Tuesday 15

1965: “Lost in Space” premieres
1968: Zond 5 launched, first circumlunar spaceflight with living creatures (tortoises)

Moon phase Wednesday 16

Moon at perigee
Venus 3° north of Moon

1848: First observation of Hyperion, moon of Saturn
1996: STS-79 Atlantis launched

Moon phase Thursday 17

Uranus at opposition
Saturn in conjunction with Sun

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

Moon phase Friday 18

Rosh Hashanah begins at sunset

1964: Saturn SA-7 launched
1977: Voyager 1 takes photo of Earth and Moon together in space
2006: Anousheh Ansari becomes first woman space tourist

Moon phase Saturday 19

Moon phase Sunday 20

Mercury in inferior conjunction
Venus 0.5° north of Regulus

1945: Wernher von Braun arrives in United States
1966: Surveyor 2 launched
1970: Luna 16 lands on Moon
1979: HEAO-3 launched
1988: Israel launches its first satellite

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