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 Post subject: Rama ?
PostPosted: Fri Oct 27, 2017 9:02 pm 
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http://www.msn.com/en-us/news/technolog ... id=UE03DHP

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This mystery object may be our first visitor from another solar system

By Amanda Barnett, CNN

Astronomers around the world are trying to track down a small, fast-moving object that is zipping through our solar system.

Is a comet? An asteroid? NASA's not sure. The space agency doesn't even know where it came from, but it's not behaving like the local space rocks and that means it may not be from our solar system.

If that's confirmed, NASA says "it would be the first interstellar object to be observed and confirmed by astronomers."

"We have been waiting for this day for decades," Paul Chodas, manager of NASA's Center for Near-Earth Object Studies, said in a NASA news release. "It's long been theorized that such objects exist – asteroids or comets moving around between the stars and occasionally passing through our solar system – but this is the first such detection. So far, everything indicates this is likely an interstellar object, but more data would help to confirm it."

NASA says astronomers are pointing telescopes on the ground and in space at the object to get that data.

For now, the object is being called A/2017 U1. Experts think it's less than a quarter-mile (400 meters) in diameter and it's racing through space at 15.8 miles (25.5 kilometers) per second.

It was discovered October 19 by the University of Hawaii's Pan-STARRS 1 telescope on Haleakala, Hawaii.

Rob Weryk, a postdoctoral researcher at the University of Hawaii Institute for Astronomy, was the first to identify the object and immediately realized there was something different about it.

"Its motion could not be explained using either a normal solar system asteroid or comet orbit," he said. "This object came from outside our solar system."

Whatever "it" is, the object isn't a threat to Earth.

NASA say that on October 14, it safely passed our home world at a distance of about 15 million miles (24 million kilometers) – that's about 60 times the distance to the moon.

Where's it going? Scientists think the object is heading toward the constellation Pegasus and is on its way out of our solar system.

"This is the most extreme orbit I have ever seen," said Davide Farnocchia, a scientist at the Center for Near-Earth Object Studies. "It is going extremely fast and on such a trajectory that we can say with confidence that this object is on its way out of the solar system and not coming back."

"It" may eventually get a better name than A/2017 U1, but since the object is the first of its kind, the International Astronomical Union will have to come up with new rules for naming the object.




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 Post subject: Re: Rama ?
PostPosted: Fri Oct 27, 2017 9:08 pm 
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No. Rama was artificial. We have absolutely no reason to assume this is anything other than natural. I was going to bemoan journalism, but they did a decent job on this.

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 Post subject: Re: Rama ?
PostPosted: Tue Oct 31, 2017 11:48 am 
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Also, it didn't go near enough to the Sun to refuel or get a worthwhile grav-asist...

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 Post subject: Re: Rama ?
PostPosted: Tue Oct 31, 2017 12:35 pm 
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The aliens decided to lock their doors and drive through without stopping.

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 Post subject: Re: Rama ?
PostPosted: Tue Oct 31, 2017 12:54 pm 
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Poohbah wrote:
The aliens decided to lock their doors and drive through without stopping.


Do you blame them?

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 Post subject: Re: Rama ?
PostPosted: Tue Oct 31, 2017 1:21 pm 
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Yeah, that's another valid reply to 'Where Are They'...

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 Post subject: Re: Rama ?
PostPosted: Wed Nov 01, 2017 5:58 am 
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jemhouston wrote:
Poohbah wrote:
The aliens decided to lock their doors and drive through without stopping.


Do you blame them?


Not at all...

Attachment:
aliens issues.jpg
aliens issues.jpg [ 64.78 KiB | Viewed 845 times ]

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 Post subject: Re: Rama ?
PostPosted: Wed Nov 01, 2017 8:33 pm 
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Poohbah wrote:
jemhouston wrote:
Poohbah wrote:
The aliens decided to lock their doors and drive through without stopping.


Do you blame them?


Not at all...

Attachment:
aliens issues.jpg

It would be ironic if, after all of our waiting, the first confirmation we get of extraterrestrial life is a vessel that speeds through the solar system, ignoring us completely.

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 Post subject: Re: Rama ?
PostPosted: Wed Nov 01, 2017 9:45 pm 
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They'll be posting two sets of Keep Out signs, one to keep other out, and the other to keep us in.

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 Post subject: Re: Rama ?
PostPosted: Thu Nov 02, 2017 8:48 am 
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And, yes, that's a couple more answers to 'Where Are They ?'

I suppose best analogy would be the North Sentinel Islanders, on the Andaman chain, who are too dangerous to approach...

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 Post subject: Re: Rama ?
PostPosted: Fri Nov 17, 2017 6:38 am 
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We won't see their near light speed slugs coming until the very last second.

Quote:
All the energy put into achieving that velocity had transformed the Intruder into a kinetic storage device of nightmarish design. If it struck a world, every gram of the vessel's substance would be received by that world as the target in a linear accelerator receives a spray of relativistic buckshot. Someone, somewhere, had built and was putting to use a relativistic bomb -- a giant, roving atom smasher aimed at worlds...



The gamma-ray shine of the decelerating half was also detectable, but it made no difference. One of the iron rules of relativistic bombardment was that if you could see something approaching at 92 percent of light speed, it was never where you saw it when you saw it, but was practically upon you...



In the forests below, lakes caught the first rays of the rising Sun and threw them back into space. Abandoning the two-dimensional sprawl of twentieth-century cities, Sri Lanka Tower, and others like it, had been erected in the world's rain forests and farmlands, leaving the countryside virtually uninhabited. Even in Africa, where more than a hundred city arcologies had risen, nature was beginning to renew itself. It was a good day to be alive, she told herself, taking in the peace of the garden. Then, looking east, she saw it coming -- at least her eyes began to register it -- but her optic nerves did not last long enough to transmit what the eyes had seen.

It was quite small for what it could do -- small enough to fit into an average-sized living room -- but it was moving at 92 percent of light speed when it touched Earth's atmosphere. A spear point of light appeared, so intense that the air below snapped away from it, creating a low-density tunnel through which the object descended. The walls of the tunnel were a plasma boundary layer, six and a half kilometers wide and more than 160 deep -- the flaming spear that Virginia's eyes began to register -- with every square foot of its surface radiating a trillion watts, and still its destructive potential was but fractionally spent.

Thirty-three kilometers above the Indian Ocean, the point began to encounter too much air. It tunneled down only eight kilometers more, then stalled and detonated, less than two-thousandths of a second after crossing the orbits of Earth's nearest artificial satellites.

Virginia was more than three hundred kilometers away when the light burst toward her. Every nerve ending in her body began to record a strange, prickling sensation -- the sheer pressure of photons trying to push her backward. No shadows were cast anywhere in the tower, so bright was the glare. It pierced walls, ceramic beams, notepads, and people -- four hundred thousand people. The maglev terminal connecting Sri Lanka Tower to London and Sydney, the waste treatment centers that sustained the lakes and farms, all the shops, theaters, and apartments liquefied instantly. The structure began to slip and crash like a giant waterfall, but gravity could not yank it down fast enough. The Tower became vapor before it could fall half a meter. At the vanished city's feet, the trees of the forest were no longer able to cast shadows; they had themselves become long shadows of carbonized dust on the ground.

In Kandy and Columbo, where sidewalks steamed, the relativistic onslaught was unfinished. The electromagnetic pulse alone killed every living thing as far away as Bombay and the Maldives. All of India south of the Godavari River became an instant microwave oven. Nearer the epicenter, Demon Rock glowed with a fierce red heat, then fractured down its center, as if to herald the second coming of the tyrant it memorialized. The air blast followed, surging out of the Indian Ocean -- faster than sound -- flattening whatever still stood. As it slashed north through Jaffna and Madurai, the wave front was met and overpowered by shocks rushing out from strikes in central and southern India.

Across the face of the planet, without warning, thousands of flaming swords pierced the sky...



Then out of no where -- out of the deep impersonal nowhere -- came a bombardment that even the science fiction writers had failed to entertain.

Just nine days short of America's tricentennial celebrations, every inhabited planetary surface in the solar system had been wiped clean by relativistic bombs. Research centers on Mars, Europa, and Ganymede were silent; even tiny Phobos and Moo-kau were silent. Port Chaffee was silent. New York, Colombo, Wellington, the Mercury Power Project and the Asimov Array. Silent. Silent. Silent.

A Valkyrie rocket's transmission of Mercury's surface had revealed thousands of saucer-shaped depressions where only hours before had existed a planet-spanning carpet of solar panels. The transmission had lasted only a few seconds -- just long enough for Isak to realize there would be no more of the self-replicating robots that had built the array of panels and accelerators, just long enough for him to understand that humanity no longer possessed a fuel source for its antimatter rockets -- and then the transmission had ceased abruptly as the Valkyrie disappeared in a silent white glare.

Presently, most of the station's scopes and spectrographs were turning Earthward, and Isak found it impossible to believe what they revealed. The Moon rising over Africa from behind Earth was peppered with new fields of craters. The planet below looked like a ball of cotton stained grayish yellow. The top five meters of ocean had boiled off under the assault, and sea level air was three times denser than the day before -- and twice as hot...



The sobering truth is that relativistic civilizations are a potential nightmare to anyone living within range of them. The problem is that objects traveling at an appreciable fraction of light speed are never where you see them when you see them (i.e., light-speed lag). Relativistic rockets, if their owners turn out to be less than benevolent, are both totally unstoppable and totally destructive. A starship weighing in at 1,500 tons (approximately the weight of a fully fueled space shuttle sitting on the launchpad) impacting an earthlike planet at "only" 30 percent of lightspeed will release 1.5 million megatons of energy -- an explosive force equivalent to 150 times today's global nuclear arsenal... (ed note: this means the freaking thing has about nine hundred mega-Ricks of damage!)

The most humbling feature of the relativistic bomb is that even if you happen to see it coming, its exact motion and position can never be determined; and given a technology even a hundred orders of magnitude above our own, you cannot hope to intercept one of these weapons. It often happens, in these discussions, that an expression from the old west arises: "God made some men bigger and stronger than others, but Mr. Colt made all men equal." Variations on Mr. Colt's weapon are still popular today, even in a society that possesses hydrogen bombs. Similarly, no matter how advanced civilizations grow, the relativistic bomb is not likely to go away...


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 Post subject: Re: Rama ?
PostPosted: Fri Nov 17, 2017 4:14 pm 
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Last second depends on how far out they were launched. I did the math once, even from proxima centauri, youd have a few months.

The big problem is realizing you're looking at a relativistic object. Once you realize that though...

A relativistic object coming towards us will be rather distinctive I think.


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 Post subject: Re: Rama ?
PostPosted: Fri Nov 17, 2017 9:11 pm 
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Kunkmiester wrote:
Last second depends on how far out they were launched. I did the math once, even from proxima centauri, youd have a few months.

The big problem is realizing you're looking at a relativistic object. Once you realize that though...

A relativistic object coming towards us will be rather distinctive I think.


Imagine though, some processors getting scrambled by a random atom of hydrogen smacking into it at 0.92c, and the entire swarm is off in deflection by 0.01 radians.

At 30 light years' range.

"We mortgaged the entire gross domestic product of our solar system to build R-bombs, and we FRAKKING MISSED?"

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 Post subject: Re: Rama ?
PostPosted: Mon Nov 20, 2017 5:29 pm 
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Update

http://www.eso.org/public/news/eso1737/?lang

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Quote:
eso1737 — Science Release
ESO Observations Show First Interstellar Asteroid is Like Nothing Seen Before
VLT reveals dark, reddish and highly-elongated object

20 November 2017

For the first time ever astronomers have studied an asteroid that has entered the Solar System from interstellar space. Observations from ESO’s Very Large Telescope in Chile and other observatories around the world show that this unique object was traveling through space for millions of years before its chance encounter with our star system. It appears to be a dark, reddish, highly-elongated rocky or high-metal-content object. The new results appear in the journal Nature on 20 November 2017.

On 19 October 2017, the Pan-STARRS 1 telescope in Hawai`i picked up a faint point of light moving across the sky. It initially looked like a typical fast-moving small asteroid, but additional observations over the next couple of days allowed its orbit to be computed fairly accurately. The orbit calculations revealed beyond any doubt that this body did not originate from inside the Solar System, like all other asteroids or comets ever observed, but instead had come from interstellar space. Although originally classified as a comet, observations from ESO and elsewhere revealed no signs of cometary activity after it passed closest to the Sun in September 2017. The object was reclassified as an interstellar asteroid and named 1I/2017 U1 (`Oumuamua) [1].

“We had to act quickly,” explains team member Olivier Hainaut from ESO in Garching, Germany. “`Oumuamua had already passed its closest point to the Sun and was heading back into interstellar space.”

ESO’s Very Large Telescope was immediately called into action to measure the object’s orbit, brightness and colour more accurately than smaller telescopes could achieve. Speed was vital as `Oumuamua was rapidly fading as it headed away from the Sun and past the Earth’s orbit, on its way out of the Solar System. There were more surprises to come.

Combining the images from the FORS instrument on the VLT using four different filters with those of other large telescopes, the team of astronomers led by Karen Meech (Institute for Astronomy, Hawai`i, USA) found that `Oumuamua varies dramatically in brightness by a factor of ten as it spins on its axis every 7.3 hours.

Karen Meech explains the significance: “This unusually large variation in brightness means that the object is highly elongated: about ten times as long as it is wide, with a complex, convoluted shape. We also found that it has a dark red colour, similar to objects in the outer Solar System, and confirmed that it is completely inert, without the faintest hint of dust around it.”

These properties suggest that `Oumuamua is dense, possibly rocky or with high metal content, lacks significant amounts of water or ice, and that its surface is now dark and reddened due to the effects of irradiation from cosmic rays over millions of years. It is estimated to be at least 400 metres long.

Preliminary orbital calculations suggested that the object had come from the approximate direction of the bright star Vega, in the northern constellation of Lyra. However, even travelling at a breakneck speed of about 95 000 kilometres/hour, it took so long for the interstellar object to make the journey to our Solar System that Vega was not near that position when the asteroid was there about 300 000 years ago. `Oumuamua may well have been wandering through the Milky Way, unattached to any star system, for hundreds of millions of years before its chance encounter with the Solar System.

Astronomers estimate that an interstellar asteroid similar to `Oumuamua passes through the inner Solar System about once per year, but they are faint and hard to spot so have been missed until now. It is only recently that survey telescopes, such as Pan-STARRS, are powerful enough to have a chance to discover them.

“We are continuing to observe this unique object,” concludes Olivier Hainaut, “and we hope to more accurately pin down where it came from and where it is going next on its tour of the galaxy. And now that we have found the first interstellar rock, we are getting ready for the next ones!”
Notes

[1] The Pan-STARRS team’s proposal to name the interstellar objet was accepted by the International Astronomical Union, which is responsible for granting official names to bodies in the Solar System and beyond. The name is Hawaiian and more details are given here. The IAU also created a new class of objects for interstellar asteroids, with this object being the first to receive this designation. The correct forms for referring to this object are now: 1I, 1I/2017 U1, 1I/`Oumuamua and 1I/2017 U1 (`Oumuamua). Note that the character before the O is an okina. So, the name should sound like H O u mu a mu a. Before the introduction of the new scheme, the object was referred to as A/2017 U1.
More information

This research was presented in a paper entitled “A brief visit from a red and extremely elongated interstellar asteroid”, by K. Meech et al., to appear in the journal Nature on 20 November 2017.

The team is composed of Karen J. Meech (Institute for Astronomy, Honolulu, Hawai`i, USA [IfA]) Robert Weryk (IfA), Marco Micheli (ESA SSA-NEO Coordination Centre, Frascati, Italy; INAF–Osservatorio Astronomico di Roma, Monte Porzio Catone, Italy), Jan T. Kleyna (IfA) Olivier Hainaut (ESO, Garching, Germany), Robert Jedicke (IfA) Richard J. Wainscoat (IfA) Kenneth C. Chambers (IfA) Jacqueline V. Keane (IfA), Andreea Petric (IfA), Larry Denneau (IfA), Eugene Magnier (IfA), Mark E. Huber (IfA), Heather Flewelling (IfA), Chris Waters (IfA), Eva Schunova-Lilly (IfA) and Serge Chastel (IfA).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile and by Australia as a strategic partner. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its world-leading Very Large Telescope Interferometer as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. ESO is also a major partner in two facilities on Chajnantor, APEX and ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre Extremely Large Telescope, the ELT, which will become “the world’s biggest eye on the sky”.
Links

Research paper in Nature
Photos of the VLT

Contacts

Olivier Hainaut
ESO
Garching, Germany
Tel: +49 89 3200 6752
Email: ohainaut@eso.org

Karen Meech
Institute for Astronomy
Honolulu, Hawai`i, USA
Cell: +1-720-231-7048
Email: meech@IfA.Hawaii.Edu

Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
Email: rhook@eso.org

Connect with ESO on social media
Usage of ESO Images, Videos and Music
Are you a journalist? Subscribe to the ESO Media Newsletter in your langu



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 Post subject: Re: Rama ?
PostPosted: Thu Dec 07, 2017 12:22 pm 
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It'll be some Alien guys teenage son, took his spacehopper out after dark with his girlfriend, had a few brews of Epsilon Eddy's Nightmare Knockout juice and started letting off shots with his dad's mass driver . . . .

"whooo-eeee baby, Ah'm gonna shoot that iddy bitty blue planet right up its a... jus' hold muh beer while I load this thang . . . here, take thuh wheel while Ah get a bead on this little bast...."

"Local starcops were called to a mass driver incident early this morning after local teens shot up the neighbourhood"

Don't ascribe to intelligence what can much more likely be down to brute stupidity. Or kids.

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PostPosted: Mon Dec 11, 2017 12:33 pm 
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Astronomers to Check Mysterious Interstellar Object for Signs of Technology

Russian billionaire Yuri Milner says if the space rock 'Oumuamua is giving off radio signals, his team will be able to detect them—and they may get the results within days.

Marina Koren9:00 AM ET
An artist’s impression of the interstellar asteroid 'Oumuamua
An artist’s impression of the interstellar asteroid 'Oumuamua ESO / M. Kornmesser
The email about “a most peculiar object” in the solar system arrived in Yuri Milner’s inbox last week.

Milner, the Russian billionaire behind Breakthrough Listen, a $100 million search for intelligent extraterrestrial life, had already heard about the peculiar object. ‘Oumuamua barreled into view in October, the first interstellar object seen in our solar system.

Astronomers around the world chased after the mysterious space rock with their telescopes, collecting as much data as they could as it sped away. Their observations revealed a truly unusual object with puzzling properties. Scientists have long predicted an interstellar visitor would someday coast into our corner of the universe, but not something like this.

“The more I study this object, the more unusual it appears, making me wonder whether it might be an artificially made probe which was sent by an alien civilization,” Avi Loeb, the chair of Harvard’s astronomy department and one of Milner’s advisers on Breakthrough Listen, wrote in the email to Milner.

A day later, Milner’s assistant summoned Loeb to Milner’s home in Palo Alto. They met there this past Saturday to talk about ‘Oumuamua, a Hawaiian word for “messenger.” Loeb ran through the space rock’s peculiarities, particularly its elongated shape, like a cigar or needle—an odd shape for a common space rock, but ideal for a ship cruising through interstellar space.

For Milner, the object was becoming too intriguing to ignore. So he’s decided to take a closer look.

Breakthrough Listen announced Monday that the program will start checking ‘Oumuamua this week for signs of radio signals using the Green Bank Telescope in West Virginia. The interstellar asteroid is now about twice the distance between the Earth and the sun from our planet, moving at a brisk clip of 38.3 kilometers per second. At this close distance, Green Bank can detect the faintest frequencies. It would take the telescope less than a minute to pick up something as faint as the radio waves from a cellphone. If ‘Oumuamua is sending signals, we’ll hear them.

The chance of an alien detection is, as always, small. But it’s not zero. And Milner thinks we should check—just in case—before ‘Oumuamua is gone for good. The object will pass the orbit of Jupiter next year, and by the 2020s will be hurtling beyond Pluto.

“Whether it’s artificial or not, we will definitely know more about this object,” Milner told me, in a video interview last week.

The new observations will likely be welcomed by the many astronomers who have been scratching their heads for weeks over this space rock. ‘Oumuamua seems to smash many of their predictions about fast-moving interstellar objects, and the more scientists delve into the data, the more puzzles they find.

* * *

The glint of ‘Oumuamua was first spotted by the Pan-STARRS survey telescope in Hawaii during its nightly scan of near-Earth objects like comets and asteroids. Its speed and orbit suggested the object was not bound by the sun’s gravity, and was not of this solar system.

At first, astronomers thought ‘Oumuamua must be a comet, based on decades of scientific literature that predicted its arrival. When our solar system was young, the biggest planets wreaked havoc as they swirled into shape and settled into their orbits. Their movements could jostle nearby material so violently that bits of rock and ice would go flying way out into the universe. The easiest objects to eject were those orbiting at the edge of the solar system, where escaping from the sun’s gravity would be easier. In our solar system, there are far more comets than asteroids lurking near the boundary before interstellar space. Astronomers expected these to be the first interstellar objects they saw.

And so astronomers checked ‘Oumuamua for a coma, a tail of evaporated material that trails comets as they pass near the sun and become heated up. They used telescopes that can detect a sugar cube’s worth of material flying off the object every second. But ‘Oumuamua showed no signs of a coma.

This was the first surprise of many.

Unlike the lumpy, potato-shaped asteroids of our solar system, the 400-meter-long ‘Oumuamua is perhaps 10 times as long as it is wide, an extreme aspect ratio that trumps any of the known asteroids. Astronomers don’t know how the universe could have produced an object such as this. Most natural interactions between an object and its surrounding medium favor the creation of rounded objects, Loeb said, like pebbles on a lakeshore made smooth by lapping water.

Further observations of ‘Oumuamua revealed it carried no traces of water ice, which suggests the asteroid is made of rock or perhaps metal. Whatever it is, the material is certainly sturdy. ‘Oumuamua rotates about every seven hours, a rate that would likely cause some rocky objects, nicknamed “rubble piles,” to crumble. ‘Oumuamua even survived a close pass with the sun in September, before it was detected, without breaking apart.

Thanks to its nonspherical shape, the asteroid is tumbling uncontrollably. “If you take an object that isn’t round and you throw it up in the air, it’ll make this complicated spinning motion,” said Jason Wright, an astronomer at Penn State University. “It just doesn’t just spin nicely along one axis.” Wright said a long journey across the cosmos can slow an object’s tumbling, but ‘Oumuamua has shown no signs of stopping its spinning.

“I’m not saying that any of that is necessarily a smoking gun or super exciting,” Milner said of ‘Oumuamua’s unusual properties. “But I think it warrants thorough investigation from a SETI standpoint.”

Karen Meech, an astronomer at the University of Hawaii Institute for Astronomy whose team discovered ‘Oumuamua, has said their observations are “entirely consistent with it being a natural object.” Analysis of the light reflected by the asteroid shows ‘Oumuamua is red, a color that would be expected for rocky bodies exposed to the cosmic radiation of interstellar space for long periods of time.

There are indeed some natural explanations for some of ‘Oumuamua’s weird properties. Some astronomers say ‘Oumuamua could be a contact binary—two objects that drift closer until they touch and fuse at one end—like our solar system’s Kleopatra, a metallic, dog-bone-shaped asteroid.

They suggest any ice on the asteroid’s surface was zapped away by high-energy particles on its journey between stars. Perhaps the asteroid is so hardy because it formed in the inner regions of a solar system, where rock and metal are more commonly found than ice. This would be tricky, since most exoplanets discovered so far orbit extremely close to their parent star, preventing them from flinging debris beyond the star’s pull. But they may have siblings, like our Jupiter and Neptune, lurking in the darkness, doing the work for them.

If ‘Oumuamua has anything exciting to tell us, it’s that our understanding of planet formation needs some work, said Gregory Laughlin, an astronomer who studies exoplanets at Yale University.“We know that planetary systems are extremely common, but the way that their process unfolds seems to be richer than anticipated,” he said.

* * *

The thought of a spaceship being dropped into planetary systems like a reconnaissance mission may sound like the stuff of science fiction. But for Milner, it’s the future. Milner is spending $100 million over 10 years to develop spacecraft technology capable of sending a tiny probe hurtling at one-fifth the speed of light toward Alpha Centauri, the nearest star system to Earth. If Milner succeeds, the 25-trillion-mile trip would be cut from tens of thousands of years, based on our current technology, to a breezy 20 years. Hundreds of these miniature probes would be deployed into the darkness in the hopes that at least one might complete the journey. Perhaps another civilization already had the same idea.

If that kind of technology were available today, Milner said he would send some kind of probe after ‘Oumuamua. “We need some new propulsion technologies to be able to do this,” he said.

The possibility that ‘Oumuamua is an artificial artifact from an advanced civilization is not spoken in whispers in the astronomy community. But there’s a healthy dose of hesitation in their discussions. Scientists must, after all, exhaust every other plausible explanation before considering ET.

“It’s sometimes mentioned in a half-joking way that people say things when they’re not quite sure whether they want you to take them seriously or not,” said Ed Turner, an astrophysicist at Princeton University. He’s intrigued by a potential SETI observation of ‘Oumuamua, but, like most astronomers, he’s not holding his breath.

“If you were betting your house, I wouldn’t bet it on this,” Turner said.

When they speak of ‘Oumuamua, astronomers recall the tale in Arthur C. Clarke’s 1973 novel Rendezvous with Rama. The year is 2131, and astronomers have detected a mysterious object beyond the orbit of Jupiter and classified it as an asteroid. Their observations reveal the object, named Rama, doesn’t follow the orbit of the sun and must have come from outside the solar system. They send a space probe to photograph Rama and find it’s in the shape of a perfect cylinder. A crewed mission is dispatched. When they land, humans discover the asteroid is an alien spaceship, carrying odd, machinelike beings that pay them little attention. There are no signs of the alien civilization that made them. After some tinkering, the human crew disembarks, leaving Rama to speed out of the solar system.

The story shares some tantalizing similarities with the current circumstances. The most skeptical astronomers point out that, aside from its vessel-like shape, ‘Oumuamua doesn’t have any of the characteristics one would imagine for an alien spacecraft. The object has followed an easy-to-predict trajectory through the solar system. Astronomers have accurately plotted its course forward and backward. Wouldn’t an alien spaceship travel at a fraction of the speed of light, and wouldn’t it slow down to take a look at things as it swept by?

“The explanation that this is a directed probe is, in my view, comically unlikely,” said Konstantin Batygin, a planetary astrophysicist at the California Institute of Technology. “This is just a chunk of debris. I think there’s nothing more to it than that.”

Astronomers predict many more interstellar asteroids, perhaps thousands, are coasting through our solar system, out of view of our telescopes. Pan-STARRS, a survey telescope designed to observe the entire visible sky night after night, found ‘Oumuamua after only four years of operation. Turner suspects the discovery—a fairly quick one—is not a case of pure luck, but a sign of more to come.

Some interstellar asteroids may be hiding, overlooked, in the archival data of Pan-STARRS. Many more will be spotted as other powerful survey telescopes, like the Large Synoptic Survey Telescope in Chile, come online in the next few years.

For Milner, it’s worth examining every interstellar object for signs of artificial technology. They could all be nothing more than space rocks, mindlessly plowing ahead. Or they could be the needle in the haystack. “It would be difficult to work in this field if you thought that every time you looked at something, you weren’t going to succeed,” said Andrew Siemion, the director of the Berkeley SETI Research Center who leads the center’s Breakthrough Listen Initiative.

And so, starting Wednesday at 3 p.m. Eastern Time, the Green Bank Telescope will aim at the first known interstellar object in our solar system. The telescope will observe the asteroid for 10 hours across four bands of radio frequency. The results may be made public within a matter of days.

Milner knows the odds are against him. But as he spoke from a conference table in his home, flanked by screens filled with radiant telescope images stretching from floor to ceiling, he smiled in excitement.

“If you look more, everywhere, I think chances are that eventually you will find something,” he said.

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