Archive for the ‘Astrobiology’ Category

Might alien life be buried under too much ice to phone Earth?

October 20, 2017

Why haven’t we had alien contact? Blame icy ocean worlds perhaps.

Enceladus.jpg

It’s only recently that astronomers have come to appreciate how common oceans are in our solar system; evidence for them can be seen on several moons of Jupiter, Saturn, and Neptune, and even distant Pluto. These worlds all have water ice as a major component of their crusts, which forms towering mountains and cracked canyons on their surfaces but melts into liquid water at lower depths. Hydrothermal vents on these ocean beds might pump nutrients into their surroundings, similar to ecosystems at the bottom of Earth’s oceans. Such nurseries for life—shielded from space by a thick ice shell—might even be more productive than our own exposed environment.

And should living organisms on icy ocean worlds evolve into intelligent creatures, they probably wouldn’t know the night sky as well as us humans. Perhaps the equivalent of their “space program” would simply be boring through to the frozen surface of their planet. Learn more here.

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Seven Alien ‘Earths’ Found Orbiting Nearby Star

February 23, 2017

Astronomers announced today the discovery of an extraordinary planetary system: seven Earth-sized planets that could all have liquid water on their rocky surfaces. The planets circle a tiny, dim, nearby star in tight orbits all less than 2 weeks long.

TRAPPIST-1 system.jpg

Although it isn’t possible today to say whether the planets harbor life, astronomers are excited because each planet’s orbit passes in front of—or “transits”—its parent star. What’s more, the system’s proximity to Earth means that answers to questions about whether the system is habitable may come in just a few years’ time with the launch of a powerful new space telescope.

The planets, which circle a star called TRAPPIST-1 just 39 light-years away, are tucked together so tightly that they routinely spangle each others’ skies, sometimes appearing as shimmering crescents and at other times as orbs nearly twice as large as the full moon.

Learn more here, here, here, here, here or here.

What a planet needs to sustain life

August 14, 2016

“Venus is too hot, Mars is too cold, and Earth is just right,” says planetary scientist Dave Brain. But why?

Have We Detected Megastructures Built By Aliens Around A Distant Star?

October 16, 2015

It has been called the most bizarre star in our galaxy and some think it just might be home to high-tech aliens.

The unlikely suggestion that aliens live in this star system is being taken so seriously that a team of astrophysicists wants to train a radio telescope in its direction to determine if any signals could indicate advanced extraterrestrial life.

According to Tabetha Boyajian, a postdoctoral astrophysicist at Yale University, the most likely natural explanation is that light from the star is being blocked by a massive swarm of comets that has descended close to the solar mass.

Dr Wright at Penn State is about to publish an alternative explanation for the star’s light patterns. He says the patterns of light are also consistent with a “swarm of megastructures” orbiting the star, perhaps formed by enormous solar collectors.

Such energy collectors are dubbed Dyson structures, named after physicist and mathematician Freeman Dyson, who suggested in 1960 that advanced civilisations would use such structures to collect massive amounts of solar energy.

A drawing of a Dyson Sphere

A drawing of a Dyson Sphere

What does that mean? It means we’re allowed to get a little bit excited! Not because aliens are a likely possibility, but because we’re in the middle of an awesome mystery the likes of which we haven’t seen before in the history of space exploration. Word is that SETI (Search for Extraterrestrial Intelligence) Institute scientists are considering devoting their time to it, and hopefully more research teams will get involved too. I seriously cannot wait to see what they come up with.

Learn more here, here or here.

Water flows on Mars

September 29, 2015

Beginning in 2011, scientists using the Mars Reconnaissance Orbiter (MRO)—the best camera looking down on Mars—found hundreds of streaks, about 5 meters wide, that appear seasonally on steep slopes. They show up during the warm season, grow hundreds of meters long, and then fade as winter approaches. For many years, the team made the obvious interpretation: the streaks meant that water was flowing. Salts were expected to be present in the water, because they lower the freezing point of water by tens of degrees, and they also make the water less likely to evaporate in Mars’s barely-there atmosphere. But until the researchers directly detected a signature for water in the streaks, or found evidence for salts precipitating out of the water, they were unwilling to declare the case solved.

Now, they have found evidence for those salts, using a different instrument on the MRO. And this suggests that water is flowing on Mars!

Salty water on Mars

Learn more, here, here, here, here, here, here or here.

The Fermi Paradox — Where Are All The Aliens?

May 7, 2015

The Fermi Paradox is really cool. There is a great written explanation of it here.

Or you could also check out this clip:

Why extremophiles bode well for life beyond Earth

October 9, 2013

Life on Earth requires three things: liquid water, a source of energy within a habitable range from the sun and organic carbon-based material. But life is surprisingly resilient, and organisms called extremophiles can be found in hostile living conditions (think extreme temperatures and little access to oxygen). Extremophiles give astrobiologists hope for life in the universe.

Three habitable worlds found around the same star

July 17, 2013

Astronomers believe they have found an alien solar system packed with a record-breaking three potentially habitable worlds.

New observations of the star Gliese 667C—about one-third the mass of our sun—is home to between five and seven planets, three of which are classified as super-Earths. All three are larger than our own planet, but smaller than gas giants like Uranus and Neptune.

Gliese 667 C Planet

But what makes all the difference is that these super-Earths orbit in what is known as the “Goldilocks Zone”—the region around a star where temperatures are just right for liquid water, a key ingredient in the recipe for life, to exist.

These planets are good candidates to have a solid surface and maybe an atmosphere like the Earth’s.

What makes this finding so exciting is that for the first time, astronomers have three potentially rocky or ocean worlds orbiting the same star. And at 22 light-years away from Earth, Gliese 667C and it’s two companion stars are considered relatively close neighbors to our solar system, making them ideal candidates for future extraterrestrial searches for life.

Learn more here or here.

The search for other Earth-like planets

April 27, 2013

Billions of stars. Billions of galaxies. A thousand years just to count all of the stars in our galaxy and then another thousand to count the galaxies in the universe.

The Odds of Intelligent Alien Life

January 21, 2013

Could there be intelligent life on other planets? This question has piqued imagination and curiosity for decades. Explore the answer with the Drake Equation — a mathematical formula that calculates the possibility of undiscovered life.