Астронет: Астрономическая картинка дня Комета Хейла-Боппа и галактика Андромеды http://variable-stars.ru/db/msg/1163757/eng |
Credit & Copyright: A. Dimai, R. Volcan, A. Zardini (Col Druscie Obs.,
ACC)
Explanation:
Which is closer: the comet or the galaxy?
Answer: the comet. In its trek through the inner Solar
System,
Comet Hale-Bopp has passed nearly in front of the Andromeda
Galaxy
(M31), seen on the lower left. At the time of this picture, March
27th, Comet Hale-Bopp
was about 10 light-minutes from the Earth,
while M31 remained about 3 million light-years distant.
By contrast, light can cross the Earth in about 1/20th
of a second, and light takes about one second to reach Earth's
Moon.
Comet Hale-Bopp is one of the largest comets
ever recorded, and although its' nucleus has never been photographed,
it is estimated from brightness and spin measurements to be about
40 kilometers across. In contrast, Comet Halley
in 1987 was measured to be 15 km, and Comet Hyakutake
in 1996 was estimated to be no more than 10 km.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.