June 14, 2010 - Mother Nature’s Particle Accelerators

Mother Nature’s Particle Accelerators Galactic cosmic rays are extremely energetic particles that come from outside the solar system and constantly bombard Earth while traveling very close to the speed of light. How these particles get accelerated to such tremendous velocities has long puzzled scientists, but recent observations of an ancient supernova remnant seem to have found the answer. This image shows part of a remnant of a star whose explosion was recorded in 185 AD. By studying this remnant in detail, a team of astronomers showed that the shock wave of the exploded star is very efficient at accelerating particles, and the energy used in this process matches the number of cosmic rays observed on Earth. The supernova remnant, RCW 86, is located about 8,200 light-years away.

Image credit:ESO / E. Helder & NASA / Chandra

Weekly Calendar

June 14-20, 2010

Holidays - Sky Events - Space History

Moon phase Monday 14

Flag Day

1967: Mariner 5 launched
1975: Venera 10 launched
1985: Vega 2 deploys lander and balloon on Venus

Moon phase Tuesday 15

Venus 4° north of Moon
Moon at perigee
Mercury 5° north of Aldebaran

1971: First Titan III-D rocket launch
2010: Soyuz TMA-19 launched carrying ISS Expedition 24/25 crew

Moon phase Wednesday 16

1963: Vostok 6 launched; Valentina Tereshkova first woman in space, still the only solo spaceflight by a woman

Moon phase Thursday 17

Mars 6° north of Moon

1985: STS-51G Discovery launched

Moon phase Friday 18

Ceres at opposition

1799: William Lassell born
1983: STS-7 Challenger launched; Sally Ride becomes first American woman in space
2009: Lunar Reconnaissance Orbiter (LRO) and Lunar Crater Observation and Sensing Satellite (LCROSS) launched

Moon phase Saturday 19

First Quarter Moon 12:29 AM ET
Saturn 8° north of Moon

1999: QuikSCAT launched

Moon phase Sunday 20

Father's Day

1985: NASA announces cola wars will take place on shuttle mission STS-51F
1996: STS-78 Columbia launched

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