spacetoday.net: space news from around the webin association with SpaceNews


Middleweight black holes discovered
Posted: Thu, Sep 19, 2002, 10:14 AM ET (1414 GMT)
Astronomers have found evidence for medium-size black holes in the centers of globular clusters. Hubble Space Telescope observations confirmed that a black hole with a mass 4,000 times that of the Sun is in the center of the globular cluster M15, while another 20,000 times as massive as the Sun is in the center of another cluster, G1. Astronomers measured the motions of individual stars and groups of stars around the centers of these clusters to measure the mass of these objects. These black holes are more massive than the stellar-mass black holes left over from supernovae, but much smaller than the supermassive black holes, billions of times as massive as the Sun, found in larger galaxies. Astronomers did note that the ratio of the mass of the black hole to the overall mass of the galaxy is the same for both globular clusters and larger galaxies — 0.5 percent — suggesting that some unknown physical principle may be at work.
<<previous article   next article>>
news in brief
Soyuz docks with ISS
Posted: Sun, Jun 10 11:12 AM ET (1512 GMT)

Curiosity detects organic molecules and methane cycle on Mars
Posted: Sun, Jun 10 11:10 AM ET (1510 GMT)

Northrop Grumman completes acquisition of Orbital ATK
Posted: Sun, Jun 10 11:09 AM ET (1509 GMT)

news links
Friday, June 22
MetService on site for planned Rocket Lab launch
Scoop.co.nz — 5:44 am ET (0944 GMT)
NZ space company prepares for launch
NEWS.com.au — 5:43 am ET (0943 GMT)
Falcon Heavy Certified For U.S. Air Force Flights
Aviation Week — 5:41 am ET (0941 GMT)


about spacetoday.net   ·   info@spacetoday.net   ·   mailing list