More Than Meets The Eye

Courtesy STScI
Courtesy STScI

A long time ago I wrote a planetarium show called More Than Meets The Eye about all the things you can see in the sky if you look with your naked eye and then enhance the view with binoculars and telescopes. Everywhere you look in the night sky you can see stars, but if you magnify the view, you can see nebulae and galaxies, details on planets and in comet tails, and even small little chunks of rock called asteroids.

The Hubble Space Telescope gives us magnified views of the universe every day. In recent weeks it spotted a small asteroid wending its way through the field of view as the telescope was studying a small companion to the Milky Way called the Sagittarius Dwarf Irregular Galaxy. You can see the trail of the asteroid as it traveled across HST’s view. The wavy path is not the actual path of the asteroid—it doesn’t actually wander quite that frenetically. It’s wandering a bit because the telescope is a) moving, and b) several different images were taken over a period of time. That’s why the trail looks interrupted and not quite straight.

What I find fascinating is the field of stars and galaxies that the HST image also shows. If you look closely you’ll see a few distant spirals, some edge-on galaxies, and some other blobs of light that are either too distant or too faint to make out good shapes. The scattering of stars across the top of the image is part of the dwarf galaxy the scientists were after when they took the images. It’s about 3.5 million light-years away, while the most distant galaxies in the image are at least a hundred million light-years away. The asteroid, on the other hand, is about 169 million miles away from us. It’s quite a panoramic view of the cosmos in one image—and definitely MORE than meets the eye!