A team of scientists has discovered a potentially habitable planet located about 20 light years from Earth.
The paper reports the discovery of two new planets around the nearby red dwarf star Gliese 581. This brings the total number of known planets around this star to six, the most yet discovered in a planetary system other than our own solar system. Like our solar system, the planets around Gliese 581 have nearly circular orbits.
The most interesting of the two new planets is Gliese 581g, with a mass three to four times that of the Earth and an orbital period of just under 37 days. Its mass indicates that it is probably a rocky planet with a definite surface and that it has enough gravity to hold on to an atmosphere, according to Vogt.
Gliese 581, located 20 light years away from Earth in the constellation Libra, has a somewhat checkered history of habitable-planet claims. Two previously detected planets in the system lie at the edges of the habitable zone, one on the hot side (planet c) and one on the cold side (planet d). While some astronomers still think planet d may be habitable if it has a thick atmosphere with a strong greenhouse effect to warm it up, others are skeptical. The newly discovered planet g, however, lies right in the middle of the habitable zone.
Sam Arbesman's prediction of May 2011 might have been too conservative. And 20 light years...that means we could send a signal there, and if someone of sufficient technological capability is there and listening, we could hear something back within our lifetime. Contact! (thx, jimray)
Strange Maps has a map of What's On Earth Tonight, basically a TV Guide for the Milky Way. The map is not that big yet because TV signals have only been sent out from Earth since the late 1920s.
The first tv images of World War II are about to hit Aldebaran star system, 65 light years [ly] away. If there's anybody out there alive and with eyes to see it, the barrage of actual and dramatised footage of WW2 will keep them shocked and/or entertained for decades to come. Which is just as well, for they'll have to wait quite a few years to catch the first episodes of such seminal series as The Twilight Zone and Bonanza (both 1959), just about now hitting the (putative) extraterrestrial biological entities of the Mu Arae area (appr. 50 ly). The Cosby Show, Miami Vice and Night Court (all 1984) should be all the rage on Fomalhaut (25 ly). Meanwhile, the sentient, tv-watching creatures near Alpha Centauri (4.4 ly), our closest extrasolar star, are just recovering from the infamous "wardrobe malfunction" during Janet Jackson and Justin Timberlake's halftime show during the 2004 Superbowl.
See also the opening scene from Contact.
A map of the Milky Way done in the style of the London tube map.
I was re-reading Carl Sagan's novel Contact recently, essentially a series of arguments about SETI wrapped into a story, and he alludes to some sort of cosmic Grand Central Station. That, coupled with my longtime interest in transit maps, got me thinking about all of this.
At the very moment that humans discovered the scale of the universe and found that their most unconstrained fancies were in fact dwarfed by the true dimensions of even the Milky Way Galaxy, they took steps that ensured that their descendants would be unable to see the stars at all. For a million years humans had grown up with a personal daily knowledge of the vault of heaven. In the last few thousand years they began building and emigrating to the cities. In the last few decades, a major fraction of the human population had abandoned a rustic way of life. As technology developed and the cities were polluted, the nights became starless. New generations grew to maturity wholly ignorant of the sky that had transfixed their ancestors and had stimulated the modern age of science and technology. Without even noticing, just as astronomy entered a golden age most people cut themselves off from the sky, a cosmic isolationism that only ended with the dawn of space exploration.
That's Carl Sagan in Contact from 1985. The effects of light pollution were documented in the New Yorker last August.
The New Yorker recently ran a feature on how a couple of mathematicians helped The Met photograph a part of The Hunt of the Unicorn tapestries. That same week, they ran from their extensive archives a 1992 profile of the same mathematicians, brothers David and Gregory Chudnovsky. The Chudnovskys were then engaged in calculating as many digits of pi as they could using a homemade supercomputer housed in their Manhattan apartment. There's some speculation that director Darren Aronfsky based his 1998 film, Pi, on the Chudnovskys and after reading the above article, there's little doubt that's exactly what he did:
They wonder whether the digits contain a hidden rule, an as yet unseen architecture, close to the mind of God. A subtle and fantastic order may appear in the digits of pi way out there somewhere; no one knows. No one has ever proved, for example, that pi does not turn into nothing but nines and zeros, spattered to infinity in some peculiar arrangement. If we were to explore the digits of pi far enough, they might resolve into a breathtaking numerical pattern, as knotty as "The Book of Kells," and it might mean something. It might be a small but interesting message from God, hidden in the crypt of the circle, awaiting notice by a mathematician.
The Chudnovsky article also reminds me of Contact by Carl Sagan in which pi is prominently featured as well.
According to Wolfram Research's Mathworld, the current world record for the calculation of digits in pi is 1241100000000 digits, held by Japanese computer scientists Kanada, Ushio and Kuroda. Kanada is named in the article as the Chudnovskys main competitor at the time.
(Oh, and as for patterns hidden in pi, we've already found one. It's called the circle. Just because humans discovered circles first and pi later shouldn't mean that the latter is derived from the former.)
