April 12th marked the 49th anniversary of human spaceflight, when Yuri Gagarin became the first person to orbit the Earth in 1961. At this moment, 13 humans are currently in low-Earth orbit, aboard the International Space Station. Several were already aboard the ISS when a Soyuz TMA-18 brought a fresh crew up from the Baikonur Cosmodrome on April 2nd – they were later joined by the crew of the Space Shuttle Discovery on the 131st shuttle mission to date (only three remaining launches scheduled). NASA recently signed a new deal with Russia for six more round-trips to the ISS, at a cost of $55.8 million per seat. Collected here are recent photos of the Space Station, its current crew, their launch vehicles, and the views from above. (38 photos total)
Here’s a neat picture from the collection (larger version at the link)
The water bubble acts as a lens and inverts the image, but the air bubble inside also acts as a lens, inverting the image once again. A lens made of air? Well, sort of. Light refracts at the interface of any two media with different indices, so you can look at it as a lens. If we lived in water, we’d probably think of air bubbles in that way. Alternately, you can think of the bubble as dividing the water bubble into two lenses for the light traveling through it, while the light not going through it passes through only one lens.
A variant on this would be if you were to inject a small sphere of a liquid with a larger index inside the water bubble, if you were on the ISS, or use glass with two different indices here on earth.