Search found 2 matches

by lweaver
Mon Jun 20, 2005 7:08 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD for 1 June 2005
Replies: 2
Views: 3052

I screwed up: the 400,000km is the earth-MOON distance, and I stupidly used it in Kepler's laws for the earth-SUN distance, a number I know well is NOT 400,000km. The correct numbers give a combined mass of roughly one solar mass. Sorry! Here is the math: GM/r^2=v^2/r, so GM/4pi^2 = r^3/T^2, where M...
by lweaver
Tue Jun 07, 2005 10:07 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD for 1 June 2005
Replies: 2
Views: 3052

APOD for 1 June 2005

APOD for 1 June 2005 gives data for a binary star system that leave me very confused. When I apply Kepler's third law using this data I get a mass of ten to the eighth solar masses for the pair! (And it is said to be a white dwarf pair!) Would someone explain this or correct me?