The Once and Future Stars of Andromeda
Image Credit:
NASA,
NSF,
NOAJ,
Hubble,
Subaru,
Mayall,
DSS,
Spitzer;
Processing & Copyright:
Robert Gendler &
Russell Croman
This picture of Andromeda shows not only where stars are now,
but where stars will be.
The big, beautiful
Andromeda Galaxy,
M31, is a
spiral galaxy
a mere 2.5 million
light-years
away.
Image data from space-based and ground-based observatories have been
combined here to produce
this intriguing composite
view of Andromeda at wavelengths both
inside and outside normally visible light.
The visible light
shows where M31's stars are now, highlighted in
white and blue hues and imaged by the
Hubble,
Subaru, and
Mayall telescopes.
The infrared light
shows where M31's future stars will soon form,
highlighted in orange hues and imaged by NASA's
Spitzer Space Telescope.
The infrared light tracks enormous
lanes of dust,
warmed by stars, sweeping along Andromeda's spiral arms.
This dust is a tracer of the galaxy's vast
interstellar gas, raw material for future
star formation.
Of course, the new stars will likely form over the next hundred million years or so.
That's well before Andromeda merges with our
Milky Way Galaxy in about 5 billion years.