The Drake equation is a theory, developed by astronomer Frank Drake in 1961, purportedly estimating how many extraterrestrial civilizations are likely to exist in the universe.
If you think about the gazillions of stars in the universe; and if you think about the gazillions and gazillions of planets likely circling these stars (the last five years, thousands have been discovered in our solar neighbourhood only!), the chance of alien life not existing must be very tiny. And the odds of intelligent life and civilizations developing must therefore also be high, just looking at the statistics of the universe.
The BBC has a very cool interactive infographic exploring the Drake equation. It also includes its detractors: after all, if alien civilizations must exist, why hasn’t any sign of them been found yet? The universe is already 13.5 billion years old, after all. Chances are that no civilization has ever developed to the point of interstellar communication without first destroying itself… More here.
The news is already a day old, but I still want to highlight it: for the first time, a rocky exoplanet has been discovered in the habitable zone surrounding a Sun-sized star. The planet, Kepler-22b, is only 2,4 times the size of Earth, its average temperature is a comfortable 22 degrees Celcius (perfect!), and according to NASA scientists the surface might consist of rock. One caveat: this is not exactly sure, and it might be that only the core consists of rock and the rest is gas…
But let’s not spoil the fun! Let’s also not spoil it by the fact that it is 600 lightyears away. Kepler is probably teeming with extraterrestrial life, and will otherwise make a great spot for colonization efforts. I can’t wait! Also check out this nice Habitable Exoplanets Catalog, a database containing the hundreds and hundreds of exoplanets currently discovered.
A new planet outside Earth’s solar system has been identified with many similarities to our own – making it the latest best potential target for life.
Kepler 22-b, which is about 2.4 times the size of Earth and lies in the so-called “Goldilocks zone”, has a relatively comfortable surface temperature of about 22C (72F) and orbits a star not unlike Earth’s sun.
But while astronomers believe that it “probably” also possesses water and land, earthlings secretly harbouring hopes that such a planet could potentially host new colonies from our own increasingly overpopulated home may be in for a disappointment.
About 600 light-years from Earth, Kepler 22-b is a considerable trek away while experts are not yet sure if it is made mostly of rock, gas or liquid.
The discovery was made by Nasa‘s Kepler planet-hunting telescope. It is the first time Kepler confirmed a planet outside Earth’s solar system in the not-too-hot, not-too-cold habitable zone.
Twice before, astronomers have announced planets found in that zone, but neither was as promising. One was disputed; the other is on the hot edge of the zone.
More than 1,000 new planet candidates have been discovered by the Kepler telescope, nearly doubling the previously known count. Ten of the candidates are close to Earth’s size while Kepler-22b is the smallest yet found to orbit in the middle of the habitable zone of a star similar to our sun.
“This is a major milestone on the road to finding Earth’s twin,” said Douglas Hudgins, Kepler program scientist at Nasa headquarters in Washington.
“Kepler’s results continue to demonstrate the importance of Nasa’s science missions, which aim to answer some of the biggest questions about our place in the universe.”
“Fortune smiled upon us with the detection of this planet,” said William Borucki, Kepler principal investigator at Nasa’s Ames Research Center at Moffett Field, California, who led the team that discovered Kepler 22-b. “The first transit was captured just three days after we declared the spacecraft operationally ready. We witnessed the defining third transit over the 2010 holiday season.”
One day, when we’ve discovered countless planets filled with water, nature and lifeforms, we’ll probably look back and wonder what the fuss of this dead, dry planet was all about. But right now, it’s all we got: the NASA Mars Reconnaissance Orbiter has revealed what looks like flowing water on Mars! It was already known that Mars in some spots harbors ice, but flowing water hadn’t been found yet.
It seems a seasonal thing though: the water only appears from the Martian spring to winter. An extremely important finding nonetheless; time to send some people there! From the NASA press conference:
Observations from NASA’s Mars Reconnaissance Orbiter have revealed possible flowing water during the warmest months on Mars.
“NASA’s Mars Exploration Program keeps bringing us closer to determining whether the Red Planet could harbor life in some form,” NASA Administrator Charles Bolden said, “and it reaffirms Mars as an important future destination for human exploration.”
Dark, finger-like features appear and extend down some Martian slopes during late spring through summer, fade in winter, and return during the next spring. Repeated observations have tracked the seasonal changes in these recurring features on several steep slopes in the middle latitudes of Mars’ southern hemisphere.
“The best explanation for these observations so far is the flow of briny water,” said Alfred McEwen of the University of Arizona, Tucson. McEwen is the principal investigator for the orbiter’s High Resolution Imaging Science Experiment (HiRISE) and lead author of a report about the recurring flows published in Thursday’s edition of the journal Science.
Some aspects of the observations still puzzle researchers, but flows of liquid brine fit the features’ characteristics better than alternate hypotheses. Saltiness lowers the freezing temperature of water. Sites with active flows get warm enough, even in the shallow subsurface, to sustain liquid water that is about as salty as Earth’s oceans, while pure water would freeze at the observed temperatures.
These results are the closest scientists have come to finding evidence of liquid water on the planet’s surface today. Frozen water, however has been detected near the surface in many middle to high-latitude regions. Fresh-looking gullies suggest slope movements in geologically recent times, perhaps aided by water. Purported droplets of brine also appeared on struts of the Phoenix Mars Lander. If further study of the recurring dark flows supports evidence of brines, these could be the first known Martian locations with liquid water.
The Dalai Lama (who, I’ve noticed, has the peculiar habit of laughing about his own jokes) has a good quote once a while:
The Dalai Lama, when asked what surprised him most about humanity, answered, “Man. Because he sacrifices his health in order to make money. Then he sacrifices money to recuperate his health. And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived.”