December 7, 2009 - Like Candles on the Moon

Like Candles on the Moon The Hubble Space Telescope has revealed some of the dimmest stars ever seen in globular clusters, those tight groupings of hundreds of thousands of stars that formed early in the Universe’s 14 billion year history. Hubble studied NGC 6397, a globular cluster 8,500 light-years from Earth, and surveyed the faintest red dwarf stars (which still fuse hydrogen in their cores) and the dimmest white dwarfs (burned-out relics of normal stars up to eight times the mass of the Sun). The light from these faint stars is as dim as the light from a birthday candle on the Moon would be if seen from Earth, and they are barely visible here as faint dots. Stars that were initially even more massive died as supernovae very early in the cluster’s life, leaving behind neutron stars, black holes, or no debris at all.

Image credit: NASA, ESA, and H. Richer (University of British Columbia)

Weekly Calendar

December 7-13, 2009

Holidays - Sky Events - Space History

Moon phase Monday 7

1905: Gerard Kuiper born
1972: Apollo 17 launched
1995: Galileo probe enters Jupiter’s atmosphere; orbiter begins prime mission
1997: Galileo Europa Mission begins

Moon phase Tuesday 8

Last Quarter Moon 7:13 pm

1964: Apollo A-002 launched
1990: Galileo makes first Earth flyby on way to Jupiter
1992: Galileo makes second Earth flyby on way to Jupiter

Moon phase Wednesday 9

1978: Pioneer-Venus 2 probes enter atmosphere of Venus
2006: STS-116 Discovery launched

Moon phase Thursday 10

Saturn 8° north of Moon

1963: Dyna-Soar project canceled
1999: Newton X-Ray Multi-Mirror Telescope launched

Moon phase Friday 11

Hanukkah begins at sunset

1863: Annie Jump Cannon born
1972: Apollo 17 lands on Moon
1993: Sotheby’s holds first auction of Soviet space hardware & artifacts

Moon phase Saturday 12

1961: OSCAR 1 launched, first amateur radio satellite
1970: Italian ground crew becomes first to launch satellite for America, Explorer 42

Moon phase Sunday 13

Geminid meteor shower

2001: Final drop test of the X-38 Crew Return Vehicle prototype

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