Carnival of Space: 203

It’s Carnival time in the Gutter again! We’re hosting this week’s round-up of space and astronomy blogging news. If you’d like to find out more or get involved yourself check out the Carnival’s homepage over at Universe Today.

We’re kicking off this week with the massive Solar flare that exploded from the Sun on 7th June. The Chandra blog explains what they had to do to protect the satellite from the incoming radiation. If you didn’t see any of the movies of the flare, or if you’re unsure just how big this eruption was I strongly recommend the following, courtesy of Matt Parker:

Next up is the Pan-STARRS1 project which has discovered a new comet in the outer Solar System which could reach naked eye visibility in March 2013. One of the astronomers who discovered the comet Richard Wainscoat outlines how it was found and what we know about its orbit.

Virtual telescopes such as Google Sky, World Wide Telescope and Wiki Sky have allowed people to explore the sky in great detail at many different wavelengths, and look for their own mysterious sky objects. However, if you don’t have some understanding of what you’re looking at you can end up with misidentifications, such as the ones discsussed by the Astroblog for comet Elenin and the mythical planet Nibiru.

If you want to know more about why astronomers use many different wavelengths for their observations check out the first of Cheap Astronomy’s two part podcast series on astronomy across the electromagnetic spectrum.

Over to Mars now. Vintage Space looks at the challenges in designing and testing the parachutes that slow the descent of the landers that are sent there. Once they reach the surface the pictures they send back can seem very familiar – head over to The Meridiani Journal to see an excellent example of “mud polygons” or mud cracks on Earth, and their striking similarity to the bedrock terrain seen by Opportunity in Meridiani on Mars.

Could Saturn’s moon Enceladus have a salt-water ocean? NASA’s Cassini spacecraft has already confirmed that there’s liquid water below the surface, but now it may also have detected salt grains in the plumes of icy spray shooting up from its surface. Both Discovery News and Weirdwarp have the full story.

Next Big Future brings news of a new supersonic business jet concept, the SonicStar, which was unveiled at the Paris airshow. It promises flight times from Paris to New York of under 2 hours thanks to its revolutionary engine design. If you want to travel a little further though, they also have an interview with writer Keith Henson about his ideas for cheaper space launches using a combination of Skylon rocket planes and concentrated lasers.

There’s two slightly more offbeat offerings to end on. First, shhh, don’t tell anyone but Universe Today has been spying on spy satellites, thanks to the skill of astrophotographer extraordinaire Thierry Legault. Check out the post if you want to know how he does it.

Finally, could the forthcoming movie Iron Sky have any basis in fact? Everyone knows that WW2 Germany developed rockets far in advance of the Allies, but some argue that in 1945 the Third Reich was on the verge of developing a space program. Armagh Planetarium’s Astronotes finds out more.

Well, that’s it for this week. Hope you’ve enjoyed this somewhat surprising journey from solar flares to spies and Nazis!

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High proper motion stars mess with Google Sky

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I was alerted to this by a post on the Bad Science forum. There one of the posters had used the position of Barnard’s Star to estimate the date a Google Sky image had been taken. Barnard’s Star has the highest proper motion of any star known. This means it moves across the sky compared to background stars. Looking at the image I wondered why Barnard’s star appeared only once as a single, very blue image. These colour images are made by combining images of the sky taken in different colour filters. These images are often taken years apart so for an object such as Barnard’s star which moves very fast across the sky the positions in each filter will be different. Hence you would expect to see one blue, one green and one red image in three different positions, this doesn’t appear to happen.

I decided to check out a few other high proper motion stars to see what they looked like. Proxima Cent is a bit weird, I can’t seem to identify it on the image, perhaps it is the blue thing on top of a background star, there is certainly a bit of noise where the UKST I plate (Google Sky uses a combination of data from the UKST, POSS telescope and the Sloan Digital Sky Survey plus a few other sources of more detailed images) position from the 1970s is. A better example is Kapteyn’s Star is a better example. Notice the bright very blue object in the upper right, that is the blue image from 1975, while the noisy thing in the middle is around the position of the red image from 1998. You can see a better subtraction for Luyten’s star.

Frankly I’m not sure about the finer points of how Google Sky make their colour images. This is clearly an artifact of the way in which they combine the images. Anybody able to use this to work out why this is happening?