An alien Earth that just might be habitable has been discovered in years-old records, thanks to sharp-eyed astronomers who gave the data a second look.
NASA’s Kepler planet-hunting telescope now belongs to the ages, with its fuel completely spent and its instruments shut down — but the planet quest continues, thanks to a treasure trove of downloaded data as well as a new generation of robotic planet-hunters.
Space agency officials declared the end of spacecraft operations today, nine and a half years after the car-sized probe was launched. The hydrazine fuel ran out about two weeks ago, signaled by a sharp drop in pressure readings for the propulsion system.
“In the end, we didn’t have a drop of fuel left over for anything else,” Charlie Sobeck, project system engineer at NASA’s Ames Research Center, said during a teleconference.
With a lot of help from the Hubble Space Telescope, astronomers now feel confident enough to publish their evidence for the first moon detected in orbit around a planet beyond our solar system.
But they’re still not completely confident.
“At this point, it’s up to us to report what we’re seeing, hand it over to the community and let the community probe it,” said Columbia University astronomer Alex Teachey, one of the authors of a study about the find published in the open-access journal Science Advances. “If they see what we see, I expect some people will be convinced and other people will be skeptical. And that’s all part of the process.”
NASA has hit the pause button on observations by its most prolific planet-hunting probe, the Kepler space telescope, so that it can download 51 days’ worth science data without interruption. The reason? Kepler’s fuel tanks are close to empty. After the download, Kepler will resume data gathering — that is, assuming there’s any fuel left.
That mysterious “alien megastructure” star is still a mystery, but the most plausible explanations appear to be dense patches of interstellar gas or dust that just happened to pass in front of the star.
That’s the upshot of analyses conducted by the astronomer who first raised the idea of an extraterrestrial construction project a year ago.
In the Astrophysical Journal Letters, Penn State’s Jason Wright and a co-author, Steinn Sigurdsson, run through a wide range of hypotheses for the behavior of a star called KIC 8462852, also known as Boyajian’s Star or Tabby’s Star.
Not even the alien hypothesis is ignored.
It’s been almost a year since astronomers first speculated that a strangely dimming star called KIC 8462852 might harbor an alien megastructure, and newly reported observations are making the case even stranger.
KIC 8462852 is also known as Tabby’s Star, because Yale astronomer Tabetha Boyajian first brought the case to light, based on observations that were collected by NASA’s Kepler space telescope and analyzed by the Planet Hunters project. The somewhat sunlike star lies about 1,500 light-years from Earth in the constellation Cygnus.
Kepler’s data revealed an erratic pattern in the intensity of KIC 8462852’s starlight, including periods when the light dimmed as much as 20 percent. Penn State astronomer Jason Wright noted that the dimming could theoretically be caused by shifts in an alien megastructure surrounding the star – something like a giant energy-generating Dyson sphere.
Thus was an Internet phenomenon born.
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.
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.”
Observations made by NASA’s Kepler space telescope suggest that the icy world known as 2007 OR10 is bigger than astronomers thought –and that’s adding to the pressure to give the probable dwarf planet an official name, nine years after its discovery.
Some of the suggestions pick up on the recent controversy over a British ship-naming contest in which Boaty McBoatface emerged as the overwhelming favorite. So how about Dwarfplanety McDwarfplanetface, or Plutoid McPlutoface?
The cause of all this mirth is a research paper in the Astronomical Journal that provides a new size estimate for 2007 OR10, which lies far out in the Kuiper Belt, the broad ring of icy material just beyond Neptune. The object traces an eccentric orbit that takes 547.51 Earth years to complete, and ranges as far out as 66.9 times Earth’s distance from the sun (6.2 billion miles).
The scientists behind NASA’s Kepler mission are using statistics to put their campaign to identify new planets into overdrive: New software that automates the process has verified 1,284 candidates as genuine planets rather than celestial “impostors,” more than doubling its database of confirmed worlds.
“This is the most exoplanets that have ever been announced at one time,” Princeton University researcher Timothy Morton said today during a teleconference revealing the latest counts.
Kepler’s official tally of potentially habitable planets close to Earth’s size took a jump as well, from 12 to 21.
NASA chief scientist Ellen Stofan hailed the rapid progress. “This gives us hope that somewhere out there, around a star much like ours, we can eventually discover another Earth,” she said in a statement.
The dramatic acceleration in the planet hunt is due to a statistical method pioneered by Morton and his colleagues, and described in a paper published in theAstrophysical Journal.