Small asteroid or comet ‘visits’ from beyond the solar system

Posted: October 27, 2017 by oldbrew in Astronomy, solar system dynamics
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A/2017 U1 may be from beyond our solar system [image credit: Tony873004 / Wikipedia]


This is real, unlike the object in the 1980s spoof ‘It Came From Somewhere Else’, described by one critic as ‘filmed on a shoestring budget, without the shoe and without the string’ – but amusing anyway. “We have been waiting for this day for decades,” said one scientist.

A small, recently discovered asteroid – or perhaps a comet – appears to have originated from outside the solar system, coming from somewhere else in our galaxy, says Phys.org. If so, it would be the first “interstellar object” to be observed and confirmed by astronomers.

This unusual object – for now designated A/2017 U1 – is less than a quarter-mile (400 meters) in diameter and is moving remarkably fast.

Astronomers are urgently working to point telescopes around the world and in space at this notable object. Once these data are obtained and analyzed, astronomers may know more about the origin and possibly the composition of the object.


A/2017 U1 was discovered Oct. 19 by the University of Hawaii’s Pan-STARRS 1 telescope on Haleakala during the course of its nightly search for Near-Earth Objects for NASA. Rob Weryk, a postdoctoral researcher at the University of Hawaii Institute for Astronomy (IfA), was first to identify the moving object and submit it to the Minor Planet Center.

Weryk subsequently searched the Pan-STARRS image archive and found it was present in images taken the previous night, but was not initially identified by the moving object processing. Weryk immediately realized this was an unusual object. “Its motion could not be explained using either a normal solar system asteroid or comet orbit,” he said.

Weryk contacted IfA graduate Marco Micheli, who had the same realization using his own follow-up images taken at the European Space Agency’s telescope on Tenerife in the Canary Islands. But with the combined data, everything made sense. Said Weryk, “This object came from outside our solar system.”

“This is the most extreme orbit I have ever seen,” said Davide Farnocchia, a scientist at NASA’s Center for Near-Earth Object Studies (CNEOS) at the agency’s Jet Propulsion Laboratory in Pasadena, California. “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.”

Continued here.

Comments
  1. Tim Hammond says:

    Rendezvous with Rama?

  2. Keitho says:

    My thoughts too ( for fun ). It has dropped out of warp speed and will shortly come to a stop between Earth and Moon. That would concentrate our thinking somewhat. *smile*

  3. A C Osborn says:

    Obviously an interstellar spaceacraft getting a slingshot energy boost and what a boost, from 15M/Sec (54,000Mph) to 27M/Sec (97,200Mph).
    It really is travelling very fast.
    Do you think they waved as they went past?

  4. oldbrew says:

    At those speeds a trip from Earth to Mars would be a breeze, timewise at least.

  5. Konrad says:

    The data is limited at the moment, but there is something very interesting about the A/2017 U1 flyby.

    It may well just be a comet or asteroid drifting in interstellar space that flew into our solar system and got a slingshot from our sun’s gravity.

    But what are the odds on its flight path?

    It descended on our solar system above the orbital plane at 25.5 km/s. Any distance inside the radius of the Ort cloud could have added some velocity if the object passed our sun behind its path in the galactic cloud. But to achieve maximum sling shot effect (galactic velocity), A/2017 U1 would need to pass behind the sun’s travel as close to the distance from the sun where 25.5 km/s is the solar escape velocity. Solar escape velocity around Mercury’s distance from the sun is around 20.3 km/s. For maximum slingshot an object at 25.5 km/s would need to fly past the sun inside the orbit of Mercury. A/2017 U1did just that.

    The force of gravity drops off exponentially with distance from the source mass. The corollary is also true. In the 58 million kilometres between Mercury and the Sun, solar escape velocity increases from around 20 km/s to 600 km/s. Somehow A/2017 U1 managed to thread the needle and pass our sun at near the optimum distance and position for maximum slingshot effect, without being captured by our sun’s gravity. What are the odds?

    What is the theoretical maximum exit velocity of a 25.5 km/s interstellar object getting a sling shot from our sun? A/2017 U1 is now travelling at 44 km/s relative to our system. If 44 km/s is close to the theoretical maximum that could be achieved by flying past our sun at 25.5 km/s, questions need to be asked.

    I have the suspicion that some green alien hoon just flipped us the tentacle.