Tag Archive | faint

Blood Oranges are just like Hubble Galaxies

Hubble CANDELS zoom

Astronomers always want better images. Sometimes it’s possible right away; other times doing better requires new technology and/or waiting for the next generation of telescopes. We have both kinds of “fuzzy blobs” in Galaxy Zoo, and during this hangout we showed several examples. For a couple of hangouts now we’ve been meaning to address some of the most frequently asked questions about the faintest, most distant galaxies we ask volunteers to classify:

  • what are they?
  • why are the images so fuzzy?
  • can we get better images of them now or in the future?

Given the data we have, the short answer to the first question is that we don’t yet know for sure — and, perhaps most importantly, we don’t need to know all the details. We can learn quite a lot from classifying even faint, fuzzy objects. Some of the faint galaxies on Galaxy Zoo are among the most distant galaxies ever imaged by the Hubble Space Telescope, and we don’t necessarily expect them to look like galaxies we see more nearby, so classifications from our volunteers are helping us to understand them even when we don’t have all the information we might want.

And what would it take to give us the information we want? What’s the future of astronomy after Hubble? How can we get better data than we have right now? Do we need to go into space to do it? (And what else are we working on right now, anyway?) Answers given in the video:

This is a great time to be working on Galaxy Zoo: there’s plenty to classify and analyze, and — of course — plenty to discuss. So stay tuned for next time!

Note: for those who prefer audio only, here’s a link to the podcast version.

What to do with faint galaxies

We’ve received a number of questions on Talk about what to do with faint galaxies, like this one:

Galaxies like this one are not stars or artifacts, they are just veeeery faint, so faint that even a telescope as powerful as Hubble is stretched to its capabilities to image them. When you do see such a faint galaxy, please just answer the questions as best you can. In this case, I’d call this one “smooth”.

Don’t worry about the pixellation. The Wide Field Camera 3 infrared pixels are larger than those of Hubble’s optical camera, but the resolution is still very high. So, even though you see pixels in the image of the galaxy above, it’s actually well resolved. It just happens to be smooth and featureless…

So, what about this one?


Can you see features despite the noise, or is it smooth? It’s your call. Remember, most of these galaxies haven’t been seen before by humans, so there’s no right or wrong answer. Just do your best!