Scientists can’t explain what huge object is blocking the light from this distant star

It’s not every day that we have permission to throw “Aliens?” out there in relation to a confounding astronomical discovery – in fact, I don’t think we ever have. But the discovery of a strange pattern of light surrounding a distant star called KIC 8462852 has seen even the most sensible astronomers throw their arms up with a, “Sure, why not?” arguing that the possibility of advanced alien technology can’t reasonably be ignored.

“Aliens should always be the very last hypothesis you consider, but this looked like something you would expect an alien civilisation to build,” Jason Wright, an astronomer from Penn State University in the US, told The Atlantic.

First up, though, a little about the star in question: KIC 8462852. Located about 1,500 light-years away between the Cygnus and Lyre constellations of our Milky Way galaxy, KIC 8462852 is brighter, hotter, and more massive than the Sun.

It was first discovered by NASA’s Kepler Space Telescope in 2009, and scientists have been tracking the light it emits ever since, along with the light of another 150,000 or so newly discovered stars. They do this because it’s the best way to locate distant planets – slight, periodic dips in a star’s brightness signal the fact that it might have one or more large objects orbiting it in a regular fashion.

These brightness dips are usually very slight, with the stars dimming by less than 1 percent every few days, weeks, or months, depending on the size of the planet’s orbit, says astronomer Phil Plait at Slate.

What makes KIC 8462852 such a strange star to study is that not only are there way more dips of brightness than expected, these dips are highly irregular. There’s no periodic orbiting going on here, just a bunch of strange, light-blocking shapes with no discernible pattern to them.

And these dimming effects are significant. Scientists are reporting that at one point, the amount of starlight dropped by 15 percent, and then at another, 22 percent. And this tells us a whole lot, says Plait:

“Straight away, we know we’re not dealing with a planet here. Even a Jupiter-sized planet only blocks roughly 1 percent of this kind of star’s light, and that’s about as big as a planet gets. It can’t be due to a star, either; we’d see it if it were. And the lack of a regular, repeating signal belies both of these as well. Whatever is blocking the star is big, though, up to half the width of the star itself!”

The most obvious explanation for hundreds of irregular dimming events is that KIC 8462852 has a mass of space junk – all kinds of rocks and dust of varying shapes and sizes – circling it in tight formation, says Ross Andersen at The Atlantic. The only problem is that this only occurs when a star is young, and the evidence points to KIC 8462852 being mature. “If it were young, it would be surrounded by dust that would give off extra infrared light,” says Andersen. “There doesn’t seem to be an excess of infrared light around this star.”

“We’d never seen anything like this star,” one of the researchers, Tabetha Boyajian from Yale University in the US, told him. “It was really weird.”

So what’s going on here? There are a number of reasonable possibilities to consider, and yep, aliens is actually one of them. First off, the scientists have already ruled out the possibility that the information they’re working with is faulty. “We thought it might be bad data or movement on the spacecraft, but everything checked out,” says Boyajian.

The best explanation we have is that at one point, another star passed into KIC 8462852’s system and the disturbance of gravity caused a huge mess of comets to be pulled in towards it before being expelled again. And there just so happens to be another star close enough to KIC 8462852 to make this a possibility.

“But that would be an extraordinary coincidence, if that happened so recently, only a few millennia before humans developed the tech to loft a telescope into space. That’s a narrow band of time, cosmically speaking,” says Andersen.

And then there’s the question of the 22 percent dimming. Could a mass of comets really block that much light? When astronomer Jason Wright from Penn State got a look at the data, he said we need to consider that perhaps we’ve caught an advanced alien civilisation in the process of building something massive near KIC 8462852.

Plait points to the so-called Dyson Sphere from several science fiction stories: a gigantic sphere made of solar panels that completely encircles a star. And he’s not opposed to the idea:

“I actually kinda like it. I’m not saying it’s right, mind you, just that it’s interesting. Wright isn’t some wild-eyed crackpot; he’s a professional astronomer with a solid background. As he told me when I talked to him over the phone, there’s ‘a need to hypothesise, but we should also approach it skeptically’ (paraphrasing a tweet by another astronomer, David Grinspoon), with which I wholeheartedly agree.”

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. We seriously cannot wait to see what they come up with.

Source: Scientists can’t explain what huge object is blocking the light from this distant star

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Scientists can’t explain what huge object is blocking the light from this distant star

Scientists Find A Double Black Hole Inside A Nearby Quasar

Artist view of a binary black hole

NASA, ESA, and G. Bacon (STScI)

The brightest objects in the universe have massive black holes at their hearts.

Quasars (“quasi-stellar radio sources”) can be brighter than entire galaxies, and they’re thought to be fueled by the friction and heat of stuff that’s getting swallowed up by a black hole. (Although light can’t escape a black hole, it can escape from the event horizon—the boundary and point-of-no-return surrounding the black hole.)

Now, it turns out that the quasar nearest to Earth, located 600 million light-years away in a galaxy called Markarian 231, is actually built around two twirling black holes. It’s a first-of-its-kind type of find, and scientists think there could be a lot more quasars with binary hearts out there.

Hubble data revealed a mysterious hole in the quasar’s accretion disk, or the ring of gas that spirals around the black hole, waiting to fall in. After doing some modeling studies, scientists concluded that the system must be made of two black holes: a large one and a small one orbiting each other.

The larger of the pair is estimated to be 150 million times more massive than our sun, while the puny companion is only four million times the mass of the sun. In a few hundred thousand years, the two will spiral into each other, resulting in what we can only guess would be the end of the universe. (Kidding!)

The team, based partly in the U.S. and partly in China, thinks the binary formed when the two galaxies merged. The merger seems to have been good for the star-forming business: Mrk 231 births stars at a rate that is 100 times greater than our Milky Way.

“We are extremely excited about this finding because it not only shows the existence of a close binary black hole in Mrk 231, but also paves a new way to systematically search binary black holes via the nature of their ultraviolet light emission,” Youjun Lu of the National Astronomical Observatories of China, Chinese Academy of Sciences, said in a press release.

Source:  SCIENTISTS FIND A DOUBLE BLACK HOLE INSIDE A NEARBY QUASAR

Scientists Find A Double Black Hole Inside A Nearby Quasar

Stephen Hawking: Intelligent Aliens Could Destroy Humanity, But Let’s Search Anyway

This week, famed physicist Stephen Hawking helped launch a major new effort to search for signs of intelligent alien life in the cosmos, even though he thinks it’s likely that such creatures would try to destroy humanity.

Since at least 2010, Hawking has spoken publicly about his fears that an advanced alien civilization would have no problem wiping out the human race the way a human might wipe out a colony of ants. At the media event announcing the new project, he noted that human beings have a terrible history of mistreating, and even massacring, other human cultures that are less technologically advanced — why would an alien civilization be any different?

And yet, it seems Hawking’s desire to know if there is intelligent life elsewhere in the universe trumps his fears. Today (July 20), he was part of a public announcement for a new initiative called Breakthrough Listen, which organizers said will be the most powerful search ever initiated for signs of intelligent life elsewhere in the universe. [13 Ways to Hunt Intelligent Alien Life]

“I am here today because I believe the Breakthrough initiatives are incredibly important,” Hawking said during a media event at the Royal Society in London. “It’s time […] to search for life beyond Earth. The Breakthrough initiatives are making that commitment. We are alive. We are intelligent. We must know.”

The new Breakthrough Listen initiative would only search for signs of intelligent life, not broadcast signals from Earth, and scientists other than Hawking have expressed concerns about hailing the attention of alien civilizations. However, a second initiative, Breakthrough Message, will host a competition open to anyone in the world, to make suggestions for the content of messages to be sent from humans to other intelligent beings.

Scientists currently have no idea what alien life-forms might look like, or how they might respond to contact from human civilization.

“Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they could reach,” Hawking said in 2010 on an episode of “Into the Universe with Stephen Hawking,” a TV show that aired on the Discovery Channel. “If so, it makes sense for them to exploit each new planet for material to build more spaceships so they could move on. Who knows what the limits would be?”

Hawking voiced his fears at the Breakthrough event, saying, “We don’t know much about aliens, but we know about humans. If you look at history, contact between humans and less intelligent organisms have often been disastrous from their point of view, and encounters between civilizations with advanced versus primitive technologies have gone badly for the less advanced. A civilization reading one of our messages could be billions of years ahead of us. If so, they will be vastly more powerful, and may not see us as any more valuable than we see bacteria.”

Astrophysicist Martin Rees countered Hawking’s fears, noting that an advanced civilization “may know we’re here already.”

Ann Druyan, co-founder and CEO of Cosmos Studios, who was part of the announcement panel and will work on the Breakthrough Message initiative, seemed much more hopeful about the nature of an advanced alien civilization and the future of humanity.

“We may get to a period in our future where we outgrow our evolutionary baggage and evolve to become less violent and shortsighted,” Druyan said at the media event. “My hope is that extraterrestrial civilizations are not only more technologically proficient than we are but more aware of the rarity and preciousness of life in the cosmos.”

Jill Tarter, former director of the Center for SETI (Search for Extraterrestrial Intelligence) also has expressed opinions about alien civilizations that are in stark contrast to Hawking’s.

“While Sir Stephen Hawking warned that alien life might try to conquer or colonize Earth, I respectfully disagree,” Tarter said in a statement in 2012. “If aliens were to come here, it would be simply to explore. Considering the age of the universe, we probably wouldn’t be their first extraterrestrial encounter, either.

“If aliens were able to visit Earth, that would mean they would have technological capabilities sophisticated enough not to need slaves, food or other planets,” she added.

The new Breakthrough Listen initiative is scheduled to operate for 10 years and will search for signs of non-naturally occurring communications in both radio frequencies and laser transmissions. The initiative will scan the 1 million stars closest to Earth in the Milky Way, as well as the 100 closest galaxies.

Source: Stephen Hawking: Intelligent Aliens Could Destroy Humanity, But Let’s Search Anyway

Stephen Hawking: Intelligent Aliens Could Destroy Humanity, But Let’s Search Anyway