An artist’s conception shows the planet TRAPPIST-1h. (NASA / JPL-Caltech)
An international research team led by a University of Washington astronomer has worked out the intricate dance of seven planets circling an ultracool dwarf star known as TRAPPIST-1, nailing down the coordinates of the outermost world in the process.
The astronomers found that all seven exoplanets follow stable orbits thanks to a regular pattern of gravitational interactions, known as orbital resonance. And they determined conclusively that the seventh planet, called TRAPPIST-1h, is too cold for life – although it was could have been warmer in its ancient past.
An artist’s impression shows a super-Earth passing across the disk of the faint red star known as LHS 1140. (CfA Illustration / M. Weiss)
It’s not the closest potentially habitable planet, but astronomers say a world 40 percent wider than Earth could be one of the best places to target in the search for life beyond our solar system.
“This is the most exciting exoplanet I’ve seen in the past decade. We could hardly hope for a better target to perform one of the biggest quests in science – searching for evidence of life beyond Earth,” Jason Dittmann, an astronomer at the Harvard-Smithsonian Center for Astrophysics, said today in a news release.
A diagram shows seven exoplanets orbiting an ultracool dwarf star known as TRAPPIST-1. If the planets were transported to our own solar system, they’d all lie within Mercury’s orbit. (ESO Illustration)
A second look at an exoplanet system 39 light-years from Earth has brought a bonanza for astronomers: not two, not three, but seven alien worlds – some of which could have acceptable conditions for life.
“I think that we’ve made a crucial step towards finding if there is life out there. … Before, it was indications,” said study co-author Amaury Triaud of Cambridge University’s Institute of Astronomy. “Now we have the right target.”
That claim is debatable, but in any case, the discovery suggests that there are even more planets out there than astronomers previously thought. Which is what astronomers have been saying repeatedly for the past decade.
“The solar system with its four (sub-)Earth-sized planets might be nothing out of the ordinary,” Ignas Snellen of the Leiden Observatory wrote in a commentary on the findings, published in this week’s issue of the journal Nature.
The ESO’s Very Large Telescope looms in the foreground of this image, and a star map has been superimposed on the sky to show the locations of Alpha Centauri and Proxima Centauri. (ESO Photo)
One of the most powerful observing instruments on Earth, the Very Large Telescope, will join the search for potentially habitable planets around the Alpha Centauri star system.
The Breakthrough Initiatives are funded by such luminaries as Russian billionaire Yuri Milner and Facebook founder Mark Zuckerberg. The effort includes in a radio search for signals from extraterrestrial civilizations, known as Breakthrough Listen; and a plan to send swarms of nano-probes through the Alpha Centauri system, known as Breakthrough Starshot.
Positron Dynamics’ concept calls for cooling down a stream of positrons — the antimatter equivalent of electrons — and smashing them into a stream of electrons. Theoretically, that could produce enough oomph to accelerate a probe to more than one-tenth of the speed of light.
How much would you pay to find out whether Alpha Centauri’s twin suns possess blue planets like Earth?
Project Blue is hoping it’s at least $10, and maybe thousands of dollars. That’s the point behind the project’s Kickstarter campaign, which aims to raise at least $1 million for a space telescope specifically designed to look closely at the Alpha Centauri system.
An artist’s conception shows a view of the surface of the planet Proxima b, with the red dwarf Proxima Centauri near the horizon. (Credi:t: M. Kornmesser / ESO)
The alien planet orbits a red-dwarf star at a distance that puts it in a zone where liquid water could conceivably exist. The fact that such a world circles the sun’s nearest stellar neighbor, 4.2 light-years away, puts it on top of the list of potentially habitable planets beyond our solar system.
Barnes, however, emphasizes the word “potentially.” During a lecture at Seattle’s Pacific Science Center, set for 7:30 p.m. tonight, the UW astronomer will delve into the opportunities and obstacles for life on Proxima Centauri b.
“We’re looking at a 15- to 20-year time frame before we can answer this question of whether it’s habitable,” Barnes told GeekWire in advance of the talk.
An artist’s conception shows Proxima Centauri b orbiting its parent star, a red dwarf, with the two other stars of the Alpha Centauri system in the far background. (Credit: M. Kornmesser / ESO)
The rumors you’ve heard are mostly true: Scientists say the star that’s closest to our solar system has a planet that could be at the right temperature for liquid water and life.
The star is called Proxima Centauri, a red dwarf that’s part of the Alpha Centauri system, 4.2 light-years away. The planet is called Proxima Centauri b, and it’s a terrestrial world whose existence has now been confirmed after 16 years of study.
It’s not yet known whether Proxima b has an atmosphere, or liquid water. But the computer models don’t rule out the possibility. That would make it the closest known exoplanet – and the closest known exoplanet with the potential for life.
As such, it could be the nearest haven for humanity in case things go horribly wrong in our own solar system. And it just so happens that scientists are working on a robotic mission to the Alpha Centauri system: The Breakthrough Starshot initiative received a $100 million kick-start from Russian billionaire Yuri Milner in April.
“We expect either to characterize it, if we get lucky, or maybe visit it in a couple of centuries,” Guillem Anglada-Escude, an astronomer at Queen Mary University of London, told reporters.
An artist’s conception shows NASA’s Kepler telescope observing four planets as they pass across the disk of their parent star. The comparative sizes of the spacecraft and the star are not to scale. (Credit: NASA / JPL)
Astronomers say they’ve confirmed the existence of 104 worlds to add to the list of extrasolar planets detected by NASA’s Kepler K2 mission, and at least two of them appear to be potentially habitable super-Earths.
The two prospects are among four planets orbiting K2-72, a red dwarf (or M dwarf) star that’s 181 light-years away in the constellation Aquarius.
All four of the planets are between 20 and 50 percent wider than Earth. They all come closer to K2-72 than Mercury comes to our own sun. But because the red dwarf is so much cooler than our sun, the worlds known as K2-72c and K2-72e lie in the star system’s habitable zone. That means it’s conceivable that liquid water could exist on those planets.
K2-72c makes a complete orbit of its sun every 15 Earth days and is thought to be about 10 percent warmer than Earth. K2-72e is farther out: It has a 24-day orbit and should be about 6 percent cooler than Earth.
Study leader Ian Crossfield, who works at the University of Arizona’s Lunar and Planetary Laboratory, said he couldn’t rule out the possibility of life arising in such red dwarf environments.
An artist’s conception shows K2-33b crossing the disk of its parent star. (Credi: NASA / JPL-Caltech)
Scientists say they’ve detected a giant planet circling a star that’s only 5 million to 10 million years old, which would make it the youngest exoplanet ever identified.
The super-Neptune-sized planet traces a super-close-in orbit, making a complete swing around its parent star every 5.4 Earth days, according a team of astronomers associated with NASA’s repurposed Kepler space telescope. The star, known as K2-33, is in the Upper Scorpius stellar association, about 500 light-years from Earth.
Infrared observations of K2-33 indicate that the star is still surrounded by the remnants of gas and dust from a protoplanetary disk. Such disks form around stars as they’re born and give rise to planets, but the disks are thought to dissipate after a few million years. That’s how astronomers figured out that the planet was so young.
“At 4.5 billion years old, the Earth is a middle-aged planet — about 45 in human-years,” Caltech astronomer Trevor David said in a news release. “By comparison, the planet K2-33b would be an infant of only a few weeks old.”
