Spaceflight Now +
|
|
|
|
|
Subscribe to Spaceflight Now Plus for access to our extensive video collections!
 How do I sign up?
Video archive
MAVEN to Mars
NASA has selected the Mars Atmosphere and Volatile Evolution spacecraft, or MAVEN, for launch to the Red Planet.
Play
Endeavour to the VAB
For its role as a rescue craft during the Hubble servicing mission and the scheduled November logistics run to the space station, Endeavour is moved to the Vehicle Assembly Building.
Play
STS-125: The mission
A detailed step-by-step preview of space shuttle Atlantis' STS-125 mission to extend the life and vision of the Hubble Space Telescope.
Play
STS-125: The EVAs
The lead spacewalk officer provides indepth explanations of the five EVAs to service Hubble during Atlantis' flight.
Play
STS-125: The crew
The seven shuttle Atlantis astronauts hold a press conference one month before their planned launch to Hubble.
Play
STS-125: NASA leaders
The leaders of NASA's Space Operations and Science directorates give their insights into the upcoming shuttle mission to the Hubble Space Telescope.
Play
STS-125: Shuttle boss
The head of NASA's space shuttle program discusses the risks and plans for Atlantis' trek to Hubble.
Play
The Hubble program
An overview of the Hubble Space Telescope program and the planning that has gone into the final servicing mission.
Play
Hubble's future science
The new instruments to be installed into Hubble and the future science objectives for the observatory are previewed.
Play
Atlantis on the pad
Shuttle Atlantis makes the slow journey from the Vehicle Assembly Building to launch pad 39A for the STS-125 mission to service Hubble.
Play
Meet the Hubble crew
Meet the crew launching on Atlantis' STS-125 mission to service the Hubble Space Telescope and learn how each became an astronaut in this special biography movie.
Play
Become a subscriber
More video
|
|
|
|
|
|
Hubble Space Telescope images overlapping galaxies
SPACE TELESCOPE SCIENCE INSTITUTE NEWS RELEASE
Posted: September 16, 2008
NASA's Hubble Space Telescope has captured a rare alignment between two spiral galaxies. The outer rim of a small, foreground galaxy is silhouetted in front of a larger background galaxy. Skeletal tentacles of dust can be seen extending beyond the small galaxy's disk of starlight.
Credit: NASA, ESA, The Hubble Heritage Team (STScI/AURA)
See a larger image here
|
Such outer dark dusty structures, which appear to be devoid of stars,
like barren branches, are rarely so visible in a galaxy because there
is usually nothing behind them to illuminate them. Astronomers have
never seen dust this far beyond the visible edge of a galaxy. They do
not know if these dusty structures are common features in galaxies.
Understanding a galaxy's color and how dust affects and dims that
color are crucial to measuring a galaxy's true brightness. By knowing
the true brightness, astronomers can calculate the galaxy's distance
from Earth.
Astronomers calculated that the background galaxy is 780 million
light-years away. They have not as yet calculated the distance between
the two galaxies, although they think the two are relatively close,
but not close enough to interact. The background galaxy is about the
size of the Milky Way Galaxy and is about 10 times larger than the
foreground galaxy.
Most of the stars speckled across this image belong to the nearby
spiral galaxy NGC 253, which is out of view to the right. Astronomers
used Hubble's Advanced Camera for Surveys to snap images of NGC 253
when they spied the two galaxies in the background. From ground-based
telescopes, the two galaxies look like a single blob. But the Advanced
Camera's sharp "eye" distinguished the blob as two galaxies, cataloged
as 2MASX J00482185-2507365. The images were taken on Sept. 19, 2006.
The results have been submitted for publication in The Astronomical Journal.
|
|
|
|
|
