The Complete Book of Space Travel by Albro Tilton Gaul
Posts tagged space
No. 16 / Evan Stremke
This simulation shows the future behaviour of a gas cloud that has been observed approaching the supermassive black hole at the centre of the Milky Way. This is the first time ever that the approach of such a doomed cloud to a supermassive black hole has been observed and it is expected to break up completely during 2013.
On July 18 of 1969, as the world waited anxiously for Apollo 11 to land safely on the surface of the Moon, speechwriter William Safire imagined the worst case scenario as he expertly wrote the following sombre memo to President Nixon’s Chief of Staff, H. R. Haldeman. Its contents: a contingency plan, in the form of a speech to be read out by Nixon should astronauts Neil Armstrong and Buzz Aldrin become stranded on the moon, never to return, followed by some brief instructions relating to its broadcast.
“A wide field meteor camera at NASA’s Marshall Space Flight Center recorded this spectacular meteor breaking up in Earth’s atmosphere on Sept. 30, 2011, 8:37 p.m. EDT. Also visible is a star-like object moving slowly toward the upper middle of the field of view — the upper stage of the Zenit booster that launched the Russian Cosmos 2219 intelligence satellite back in 1992. Orbiting 500 miles above Earth, this empty rocket body can get bright enough to be seen with the unaided eye.”
[Flash 9 is required to listen to audio.]
This is the sound of the aurora on Saturn. Pretty eerie, no?
There is no sound in space. Outside planets and stars, molecules are spread out too thin for sound to propagate. It follows, then, that we can’t really hear sounds planets emit into space. But radio waves—electromagnetic waves with wavelengths longer than infrared light—are, as we know, handy for representing sound. And so it makes sense for us to interpret radio waves, whether originally encoding sound or not, as sound. These are radio waves emitted in conjunction with auroras around Saturn’s poles, similar to the northern and southern lights on Earth. They were picked up by the Cassini spacecraft and then interpreted as sound. But the sound was not in the audible range, so it has been downshifted by a factor of 44. And finally, so as not to bore us to death, it has been speeded up by a factor of 22. Realize, then, that many human choices were made in order for us to be able to “listen to space.” But if you can accept that, you can enjoy this.
