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July 4, 2016 - Missing Links in Star Evolution

Missing Links in Star Evolution  The bright golden spheres at the center of the star-forming region W33—seen here in an image acquired by NASA’s Spitzer Space Telescope—are the precursors to the birth of very massive stars, literally “missing links” in stellar evolution. Nicknamed “yellow balls” by the citizen scientists who first noticed them in the infrared Spitzer data, each is hundreds of times wider than our solar system. They are enormous clouds made up of organic molecules, called polycyclic aromatic hydrocarbons, that will eventually condense and ignite stars at their cores. The newborn stars will then begin to blast any remaining material around them out into space with their stellar winds, turning the former yellow balls into green-and-red bubbles like the ones seen elsewhere around W33.

Image credit: NASA / JPL-Caltech

Weekly Calendar

July 4-10, 2016

Holidays - Sky Events - Space History


Moon phase Monday 4

Independence Day

New Moon 7:01 AM ET
Earth at aphelion

1054: Crab Nebula supernova observed
1868: Henrietta Swan Leavitt born
1997: Mars Pathfinder lands on Mars
2005: Deep Impact probe collides with comet Tempel 1
: STS-121 Discovery launched
2016: Juno spacecraft begins orbiting Jupiter

Moon phase Tuesday 5

1966: Apollo-Saturn 203 launched
1982: Space Shuttle Challenger arrives at Kennedy Space Center for first time

Moon phase Wednesday 6

Mercury in superior conjunction

1687: Isaac Newton publishes his Principia

Moon phase Thursday 7

Pluto at opposition

1995: Final test flight of DC-X rocket
1998: First satellite launch from a submarine
2003: Mars rover Opportunity launched
2016Soyuz MS-01 launched carrying ISS Expedition 48/49 crew

Moon phase Friday 8

1994: STS-65 Columbia launched
2009: First flight test of Max Launch Abort System
2011: STS-135 Atlantis launched, final shuttle mission

Moon phase Saturday 9

Jupiter 0.9° north of Moon

1945: White Sands Missile Range opens
1979: Voyager 2 flies past Jupiter

Moon phase Sunday 10

1962: Telstar 1 launched, allowing transatlantic transmission of TV signals
1992: Giotto spacecraft flies past comet Grigg-Skjellerup

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