Getty Images/VW Pics

You've Never Seen a Picture of the Entire Milky Way

By: Ashley Hamer

It's easy to believe that a picture of the Milky Way exists—but it doesn't.

August 01, 2019

Search the internet for pictures of the Milky Way — our home galaxy — and you'll find all sorts of images: bright smudges across the night sky taken by high-end cameras, a horizontal streak taken by powerful telescopes, and an entire spiral galaxy taken by — wait a second. If we live inside of the Milky Way, how do we have pictures of the entire Milky Way? Spoiler alert: We don't. Not real ones, anyway.

The Hubble Heritage Team/AURA/STScI/NASA

That's Here, That's Home

Earth is located in the Milky Way, but it's nowhere near the middle. We're about 25,000 light-years from the supermassive black hole at the center, and also 25,000 light-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 between the center and the edge. The galaxy itself is shaped like a disc, with a bulge in the center and some warping thanks to the pull of the galaxies nearby.

If you head for an area mostly free of light pollution, like a Dark Sky Park, you can gaze up at and see a faint glowing band streak across the night sky. That's the cross-section of the Milky Way we can see from our vantage point on Earth. (To return to the metaphor, if you were sitting on the outer edge of a vinyl record, you would see it as a flat line, not a circle. Same goes for our galaxy.)

But that's from ground level. What about from a spacecraft?

So Close and So Far

The spacecraft that has traveled the farthest from Earth is Voyager 1. On the 40th anniversary of its launch in 2017, the craft was 13 billion miles (21 billion kilometers) away. To put that in perspective, one light-year is about 5.9 trillion miles (9.5 trillion kilometers), and our region of the Milky Way is 1,000 light-years thick. It's safe to say we're not going to leave our galaxy in your lifetime.

But that's not to say we don't have some awesome pictures of what we can see — 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 light wavelengths, which astronomers piece back together so they can see past the gas and dust as far into the center as possible. And those same telescopes can see other galaxies in their entirety, gathering data that artists use to inform their estimations of what our galaxy actually looks like.

In that way, the images you've seen of the Milky Way are a lot like the ones you've seen of living dinosaurs. No one has seen either with their own eyes, but decades of research has enabled us to make a pretty accurate guess of what they look like.

This article first appeared on Curiosity.com.

Next Up

We Have Liftoff: Congratulations to NASA and SpaceX

Here's to NASA, SpaceX, Astronauts Bob Behnken and Doug Hurley, and all of the engineers, scientists, and staff involved with the Saturday, May 30th historical launch.

Quiz: Test Your Space Exploration Knowledge

Ahead of the historic May 27th NASA and SpaceX crewed space launch, test your space exploration knowledge!

World's First Malaria Vaccine Offers Hope to Millions

Tens of thousands of lives could be saved each year from sickness and death caused by malaria following the World Health Organization (WHO) approval of a first-ever vaccine. Scientists have recommended the RTS,S vaccine for children in sub-Saharan Africa and other high-risk areas to prevent one of the world’s oldest and deadliest infectious diseases.

Where should we go? The Moon or Mars?

There’s been a lot of excitement around space exploration recently. Astrophysicist Paul M. Sutter discusses the viability between the Moon and Mars.

What are the Chances of Life Appearing On…Earth?

Just how lucky are we on Earth? What were the chances that life would arise, let alone lead to intelligence?

4 Reasons Why Earth is the Best Planet to Call Home

Since 1970, folks from around the world have gathered together to celebrate Earth Day, an appreciation for all the good stuff we’ve got here on the Earth – and a reminder to try not to mess it up. But what’s so special about the Earth, anyway?

The Kuiper Belt: When Solar Systems Dance

Pluto isn't alone after all. Besides being the home of Pluto, the Kuiper belt hosts dwarf planets, and smaller bits of rock and ice.

Survival Chemistry: The Ingredients for Life on Earth

Oxygen, hydrogen, carbon, and a few other elements from the periodic table make up 99% of our bodies.

Following Blue Origin’s NS-12 Rocket Launch

Blue Origin, Billionaire Jeff Bezos’ spaceflight company, is rescheduled to launch its NS-12 reusable spacecraft on Wednesday, December 11. Watch it LIVE.

That’s a (Weirdly) Big Black Hole!

Recently astronomers identified a black hole near a star called LB-1 and they found out that the black hole is 70 times the mass of the sun. This is a mystery because the biggest black holes we can get from the deaths of the most massive stars are around 30 times the mass of the sun, so how did black hole get this big?