At a Glance: Space Telescopes vs Ground-based Telescopes

Video Player

Video Versions

Which type of telescope produces the clearer image -- ground-based or space telescope?

Hubble Anniversary (20th & 25th)
Produced by the Space Telescope Science Institute’s Office of Public Outreach.
All images, illustrations, and videos courtesy of NASA, ESA, and STScI except:
·       Ground-based image of Carina Nebula © R. Gendler, J.-E. Ovaldsen, C. Feron, and C. Thone
·       Twinkling star movie courtesy of Applied Optics Group (Imperial College), William Herschel Telescope
·       Gran Telescopio Canarias photo courtesy of Victor R. Ruiz
·       M51 image from Gran Telescopio Canarias courtesy of IAC/GTC
·       Taurus constellation drawing from Firmamentum Sobiescianum sive Uranographia by Johannes Hevelius, courtesy of the United States Naval Observatory
Written by Vanessa Thomas and John Stoke
Designed by Marc Lussier and John Godfrey 
Music courtesy of Associated Production Music


 Text, at-a-glance. Mirror comparison. 

Photo of Gran Telescopio Canarias 

Perched atop a mountain in the Canary Islands, the Gran Telescopio Canarias has one of the largest mirrors of any telescope in the world. 

Its main mirror, which is made of 36 smaller segments, is 10.4 meters (or 34 feet) across. 

Drawing of Gran Telescopio Canarias mirrors 

One of the largest mirrors in space belongs to the Hubble Space Telescope. 

The Hubble Space Telescope's main mirror is 2.4 meters (about 8 feet) across -- less than a quarter the size of the Gran Telescopio Canarias mirror. 

Both telescopes capture stunning views of our universe, such as this spiral galaxy. 

Side-by-side comparison of photos taken by Gran Telescopio Canarias and Hubble. 

But the view from space is so much sharper that a relatively small telescope in space, like Hubble, can see far better details than a larger telescope can from the ground.