Comments on: Galaxy Zoo!

By: Find your own Supernovae! | Cosmic Variance | Discover Magazine

Find your own Supernovae! | Cosmic Variance | Discover Magazine — Fri, 14 Aug 2009 04:53:36 +0000

[...] posted before about Galaxy Zoo, and see also Phil Plait’s posts introducting the zoo, oncounterintuitive [...]

By: Apparent Brightness · The Galaxy Zoo

Apparent Brightness · The Galaxy Zoo — Fri, 02 Nov 2007 07:53:21 +0000

[...] has already been all over the news and blogs, but I cannot resist to comment a little more on the newly opened Galaxy [...]

By: mollishka

mollishka — Thu, 26 Jul 2007 02:41:35 +0000

Potentially relevant (though not from any of the GalaxyZoo crowd): http://arxiv.org/abs/0707.3793

By: mollishka

mollishka — Wed, 25 Jul 2007 03:20:58 +0000

The whole CW or CCW thing does seem…. odd, though if people consistently say the same chirality, perhaps the sprial classification is more believable? “Does it have a bar?” seems more straightforward, although again difficult with the SDSS resolution.

Mmmm, galaxies…

By: Paul

Paul — Tue, 24 Jul 2007 13:44:45 +0000

I visit GalaxyZoo between reviewing proposals at NSF! And no, I’m not in the astronomy division, so you can’t blame any declines on me…

Can’t wait for the “My Galaxies” function to be enabled, or the brief glimpse we got of “My Statistics” (since disappeared…).

By: 1234567890

1234567890 — Mon, 16 Jul 2007 04:00:34 +0000

http://flickr.com/groups/galaxyzoo/

You can submit interesting finds to this Flickr group.

By: Matt

Matt — Sun, 15 Jul 2007 14:50:35 +0000

Hey. I found a set of Hoag objects/polar ring galaxies (one even merging), but how the hell was I meant to classify those suckers; Just about all you can do is send them in via email.

Amazing though.

By: Ben

Ben — Sun, 15 Jul 2007 01:54:17 +0000

Risa – Now that I’ve read their tutorial more carefully, it looks like they mention irregular galaxies, but they put them in the “Star/Don’t Know” class (!) That’s probably where blobby things were intended to go, but it seems like an unfortunate choice. It’s somewhat odd that they force you to choose spirals being clockwise, anti-clockwise, or edge-on, since it’s entirely possible to have a disk galaxy whose spiral pattern is indistinct at SDSS resolution. I took their test and got 15/15 (not that I’m boasting or anything) but there was one disk where I was guessing at the sense of the spiral.

A greater value of this method than spins, I think, would be to find rare and interesting objects.
However, one problem with having Web 2.0 classify for unusual objects is that you have to teach the classifiers what is unusual. Maybe they’ll learn after looking at 1000 galaxies Mergers are one example, which they already do have a button for. Although I already know of a student who’s gone through SDSS looking for mergers (and I’m trying to do it automatically), so in the fullness of time it would be interesting to compare the results.

By: Risa

Risa — Fri, 13 Jul 2007 20:02:13 +0000

Hey Ben — I agree, they do seem to sort of be pushing this angle in the website and press. Frankly that seems a bit silly to me, since I agree, there’s almost no way theorists would believe it if they do find a result. However, I do think they have much broader goals, one of the participants told me that they have a number of projects in galaxy formation and cosmology intended. But yes, I think if they are going to do it they should trust people more. In particular, I think it’s silly to trust *individuals* much, but I’m guessing they can pretty easily get 10 classifications per galaxy (apparently, they had 300,000 classified after one day) — and then it makes sense to have more categories. Fewer categories in some sense makes things *less* reliable, since I get all confused about e.g. putting star forming blobby looking things in the same category as classic massive ellipticals.

By: Ben

Ben — Fri, 13 Jul 2007 18:28:32 +0000

Great, now that I’ve finally figured out how to do visual morphological classification, now SDSS is trying to put me out of work (or “render redundant” in the British phrase) by outsourcing classification to a bunch of unpaid Web 2.0ers.

Seriously, I think the project is trying to do something limited, which is to classify which way galaxies are rotating (CW or CCW) to look for very large scale spin alignments. This is a low percentage project in some sense (as in, even if they turn up a signal, hordes of theorists will refuse to believe it at first). It’s likely that they didn’t want to assign a bunch of untrained classifiers the task of finding unusual or interesting objects. Your point may be that they should be trusting their audience more.