Welcome to the WWT Data Blog. This is where we will post details of new data sets as they come in, and ask for volunteers to help us with data and image processing tasks. (Yes, we need volunteers - we're just a small group within Microsoft Research!)

To begin, let's briefly describe some of the main types of data in WWT.

- Studies. These are individual images of specific objects in the sky e.g. a Chandra Observatory photograph of the Crab Nebula in the X-Ray wavelength. We typically store studies in tangential projection like astronomers do. We started off with a few hundred images from the Hubble, Spitzer, and Chandra observatories. and we are currently processing hundreds more, from those and other sources.

- Surveys. These are images of all/most of the sky in some wavelength. WWT has at most two surveys active at any time - the foreground survey and the background survey - and you can 'go between' them using the slider at the bottom of the screen. The default background survey is the Digitized Sky Survey (DSS), which we represent as a square image that is a million pixels by a million pixels. Yes, that really is one terapixel :)

- Planetary Surfaces. These are textures and/or elevation maps of various planets and moons.

- Panoramas. At the moment, we've only got a few of these, from the NASA/JPL Mars Rovers, but that is just the start. You can also load in your own panoramas. If you have a high-resolution panorama that you'd like WWT to display, let us know. We are especially looking for panoramas of telescopes at various observatories around the world.

- Catalogs. These are lists of stellar objects, such as the NGC, Messier and IC catalogs.  Information for over 40 000 objects are stored locally on your hard drive when WWT installs.

Surveys, surfaces, and panoramas are all stored in a projection format specific to WWT called TOAST. This projection treats different parts of the sky the same - you don't (for example) get that horrible distortion in the polar regions that you get with equirectangular projection. There'll be more on it in a future post.

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Originally posted by dinos. Migrated to new blog location by derickc.