Y’all’ve Never Seen a Picture show of the Unabridged Milky Way
It’southward like shooting fish in a barrel to believe that a picture of the Milky way exists—simply it doesn’t.
Search the internet for pictures of the Milky Way — our domicile galaxy — and you’ll find all sorts of images: vivid smudges across the dark heaven taken past high-end cameras, a horizontal streak taken by powerful telescopes, and an entire screw galaxy taken by — wait a second. If we live inside of the Milky Way, how practice we have pictures of the unabridged Galaxy? Spoiler alert: We don’t. Not real ones, anyway.
The Hubble Heritage Team/AURA/STScI/NASA
That’s Here, That’due south Home
Earth is located in the Milky way, but information technology’s nowhere about the eye. We’re about 25,000 lite-years from the supermassive black hole at the center, and also 25,000 lite-years from the outer edge. As Matt Williams writes for Universe Today, if the Milky way were a vinyl record, we’d be in the groove halfway betwixt the center and the edge. The milky way itself is shaped like a disc, with a bulge in the center and some warping thanks to the pull of the galaxies nearby.
If y’all caput for an expanse mostly free of low-cal pollution, like a Night Sky Park, you can gaze up at and see a faint glowing band streak across the night sky. That’s the cantankerous-department of the Galaxy nosotros tin see from our vantage bespeak on Earth. (To return to the metaphor, if you were sitting on the outer border of a vinyl record, you would see it as a apartment line, non a circle. Aforementioned goes for our milky way.)
But that’s from ground level. What nigh from a spacecraft?
Then Shut and So Far
The spacecraft that has traveled the farthest from Earth is Voyager i. On the 40th ceremony of its launch in 2017, the craft was thirteen billion miles (21 billion kilometers) away. To put that in perspective, one lite-twelvemonth is about v.9 trillion miles (ix.five trillion kilometers), and our region of the Galaxy is 1,000 light-years thick. It’southward safe to say we’re non going to leave our galaxy in your lifetime.
But that’s non to say we don’t have some crawly pictures of what we can run across — and even some dependably accurate artist’s renderings of what we can’t. Powerful telescopes like Hubble, Chandra, and Spitzer (and soon, James Webb) capture images of our galaxy in many different calorie-free wavelengths, which astronomers piece back together and so they can see past the gas and grit every bit far into the centre as possible. And those aforementioned telescopes tin can see other galaxies in their entirety, gathering data that artists use to inform their estimations of what
galaxy really looks like.
In that mode, the images you’ve seen of the Milky Way are a lot like the ones yous’ve seen of living dinosaurs. No one has seen either with their ain eyes, simply decades of research has enabled us to make a pretty accurate approximate of what they look like.
This commodity first appeared on Curiosity.com.