Go into your
backyard about 20:30 p.m. EST or thereabouts this weekend and you can see the
most incredible thing - the Andromeda Galaxy - one of the farthest objects
visible to the naked eye. If you know where to look. Locating the 'other '
major galaxy in our Local Group is an exercise in stargazing on a grand scale,
and the beginning of fall is absolutely the best time to take a look at it.
You've
probably seen the Andromeda Galaxy before in incredible pictures from NASA, but
if you've never seen it with your own eyes, now is the time. After all, of the
two trillion galaxies estimated to be out there in the Universe, it's the
Andromeda Galaxy that is by far the easiest to see, and perhaps one of the most
beautiful.
Andromeda
Galaxy imaged from 12,500 feet in California's White Mountains
What is the
Andromeda Galaxy?
The nearest
major spiral galaxy to our own Milky Way galaxy, the Andromeda Galaxy (also
called M31) is 2,538,000 light years from Earth. It's a pretty similar galaxy
to our own, and astronomers have long used it as a reference point for studying
the Milky Way. Since we are in the Milky Way, it's that much more difficult to
study it, so the Andromeda Galaxy provides an easy way of looking at our own
galaxy in its entirety.
How long
would it take to get to the Andromeda Galaxy?
Forget it!
Although it may be one of the closest galaxies to our own, since the Andromeda
Galaxy is 2.5 million light years distant it would take 2.5 million years to
get there if (and it's a huge 'if') we could travel at the speed of light. In
short, your best chance of seeing the Andromeda Galaxy in close-up is by using
a backyard telescope, not a spacecraft. However, you can see also see M31 with
both the naked eye and through any pair of cheap binoculars.
The
Andromeda Galaxy, or M31, taken from Spain using a Canon DSLR attached to a
telescope. JAMIE CARTER
Where is the
Andromeda galaxy in the night sky?
At this time
of year, the Andromeda Galaxy is rising in the eastern sky after dusk, but it
takes some practice to find it.
So it's
important to familiarize yourself with the two constellations either side of
it, Pegasus and Cassiopeia. If you look to the east you'll see the Great Square
of Pegasus, hanging above the horizon in a diamond shape (you can call it the
Great Diamond of Pegasus if you want). Of its four bright stars, identify the
one furthest left, called Alperatz (also called Sirrah), which is about 97
light years distant. Now turn to the north-east and find the W-shaped
constellation of Cassiopeia, and more specifically, the V-shape on the
right-hand side, closest to the Great Square.
That V shape
points straight towards the Andromeda Galaxy, but to find the exact location
it's better to go from Alperatz.
If you are
under very dark skies you can do this with the naked eye, though most people
will be much better off using any pair of binoculars. With Alperatz in the
field of view, go two bright stars left and range your binoculars about the
same distance up to find a milky patch - that's the Andromeda Galaxy. It's
actually in the constellation of Andromeda; although Alperatz is the brightest
star in the Great Square of Pegasus, it's also the head of Andromeda.
How to look
at the Andromeda Galaxy
What does
the Andromeda Galaxy look like? A fuzzy blob, that’s what. If it disappoints
you, you're not looking at it properly. The human eye's peripheral vision is
the most sensitive to brightness, whereas it's center is more sensitive to
color, so when looking at a galaxy - an object with incredible brightness -
look slightly to the left or right and you'll be surprised by how much more of
it you see.
That applies
to both naked eyes observing and when using binoculars, though if you are
looking at the Andromeda galaxy through a telescope, look slightly to the left
or right of it, depending on which eye you're observing with.
Artwork of
the Milky Way Galaxy colliding with the Andromeda Galaxy in 6 billion years
time. You're looking at the combined light of a trillion stars. If that's not
bright enough for you, know that the Andromeda Galaxy is headed straight for us
at 250,000 miles per second and will eventually dominate the entire night sky.
Sadly, that's not going to happen for 3.75 billion years …
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