Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×
Space Earth

A Star Grazed Our Solar System 70,000 Years Ago, Early Humans Likely Saw It (space.com) 164

schwit1 shares a report from Space.com: Some distant objects in our solar system bear the gravitational imprint of a small star's close flyby 70,000 years ago, when modern humans were already walking the Earth, a new study suggests. In 2015, a team of researchers announced that a red dwarf called Scholzs star apparently grazed the solar system 70,000 years ago, coming closer than 1 light-year to the sun. For perspective, the suns nearest stellar neighbor these days, Proxima Centauri, lies about 4.2 light-years away. The astronomers came to this conclusion by measuring the motion and velocity of Scholzs star -- which zooms through space with a smaller companion, a brown dwarf or "failed star" -- and extrapolating backward in time. Scholz's star passed by the solar system at a time when early humans and Neanderthals shared the Earth. The star likely appeared as a faint reddish light to anyone looking up at the time, researchers with the new study said. The study has been published in the journal Monthly Notices of the Royal Astronomical Society: Letters.
This discussion has been archived. No new comments can be posted.

A Star Grazed Our Solar System 70,000 Years Ago, Early Humans Likely Saw It

Comments Filter:
  • Grazed? (Score:5, Informative)

    by Viol8 ( 599362 ) on Friday March 23, 2018 @05:23AM (#56311615) Homepage

    One light year is still WAY beyond the bounds of our known solar system and lets nor forget that the oort cloud is still pretty theoretical and no one has actually seen one of these objects yet in situ (though the claim is this is where comets come from) unlike those in the kuiper belt. So saying it grazed out solar system is pushing it a bit. If it had strayed into the kuiper belt yes , otherwise, umm, not really.

    • Grazing
      Grazing is a method of feeding in which a herbivore feeds on plants such as grasses, or other multicellular organisms such as algae.

      • You'd best hope that the clue-by-four heading your way just grazes your cranium.

      • graze(2)
        rez
        verb
        gerund or present participle: grazing
        scrape and break the surface of the skin of (a part of the body).
        "she fell down and grazed her knees"
        synonyms: scrape, abrade, skin, scratch, chafe, bark, scuff, rasp, break the skin of, cut, nick, snick; excoriate
        "he grazed his knuckles on the corner of the fuse box"
        touch or scrape lightly in passing.
        "his hands just grazed hers"
        synonyms: touch, touch lightly, brush, brush against, rub lightly, shave, skim, kiss, caress, sweep, scrape, glance off, cl

    • Comment removed based on user account deletion
      • by HiThere ( 15173 )

        It's more complicated than that. The extent of the Oort cloud is determined by where things that are nearly stationary WRT the gravitational dominants would fall towards the Sun rather than towards some other source. So a star approaching will alter the shape (and membership) of the cloud, as it's moving a new strong gravitational field into the area. Also it's not a sphere, being shallower in the direction of the Alpha Centuari system, because that's got it's own area of dominance, and it extends furthe

      • Most comets are part of the solar system in the sense that they simply orbit the sun, the rest are in the Kuiper belt.
        If there is a Oort cloud (we actually don't know that) objects from there only get kicked closer to sun when their orbits are changed by a passing big object.
        Claiming that objects that are a light year away belong to our solar system is rather esoteric, don't you think so? The solar system is traveling with about 83000 km/h or 52000mph through the galaxy.
        If the Oort cloud would be similar fa

    • by surfcow ( 169572 )

      "Less than one light year" leave a lot of slop.

      If the wayward sun perturbed the Oort cloud,
      it likely showered the Earth with random crap
      for 10s of millions of years.

      Static systems are sensitive.

  • Sigh. (Score:4, Insightful)

    by ledow ( 319597 ) on Friday March 23, 2018 @05:25AM (#56311619) Homepage

    1 light-year is 63,241 AU.

    An AU is the distance from the Earth to the Sun.

    The solar system is about 40AU (depending on your definition of planet).

    So "close" is really... well, testing things a bit. Astronomically, yes, very close.

    Practically? It's 20,000 times the size of the entire solar system away and to my knowledge only two objects have ever left the solar system.

    Chronologically? It happened 70,000 years ago which, again, is tiny in astronomical terms but it's already long gone. We could do nothing about it in a reasonable time, we'd barely be able to study it, and if it was slightly to the left we'd all be interstellar dust (again) by now.

    Though interesting, it's hardly close or anything we can really utilise or study,

    I'd be more worried along the lines of "chances are something else could come and go this and wipe us out and likely we'd never know it was going to happen". Not just stray asteriods (which obviously would be knocked for six by something like this straying close) but an entire damn star. That's solar-system-ending.

    • Re:Sigh. (Score:5, Informative)

      by breeze95 ( 880714 ) on Friday March 23, 2018 @07:58AM (#56312085)

      1 light-year is 63,241 AU.

      An AU is the distance from the Earth to the Sun.

      The solar system is about 40AU (depending on your definition of planet).

      So "close" is really... well, testing things a bit. Astronomically, yes, very close.

      Practically? It's 20,000 times the size of the entire solar system away and to my knowledge only two objects have ever left the solar system.

      Chronologically? It happened 70,000 years ago which, again, is tiny in astronomical terms but it's already long gone. We could do nothing about it in a reasonable time, we'd barely be able to study it, and if it was slightly to the left we'd all be interstellar dust (again) by now.

      Though interesting, it's hardly close or anything we can really utilise or study,

      I'd be more worried along the lines of "chances are something else could come and go this and wipe us out and likely we'd never know it was going to happen". Not just stray asteriods (which obviously would be knocked for six by something like this straying close) but an entire damn star. That's solar-system-ending.

      The solar system is way bigger than 40 AU. The Oort cloud is part of the solar system and it extends to about 3 light years. So, the solar system extends, at least, to 3 light years. Not to mention, the sun's magnetic bubbles extend that far. I'm not sure why you stopped at the last planet and not include the Kuiper Belt and Oort Cloud as part of the solar system.

      • by KHKw2k ( 5148547 )

        Because the poor gentleman wanted to feel smarter than he was and superior to "them experts".

      • and if it was slightly to the left we'd all be interstellar dust (again) by now.

        Who's left? Sol's left, or Scholtz Star's left? How do you express left in three dimensions?

    • by Muros ( 1167213 )

      The solar system is about 40AU (depending on your definition of planet).

      There are many more sattelites of the sun than just the planets, some with known orbits that go far beyond 40AU out. You can look at some of the known ones https://en.wikipedia.org/wiki/... [wikipedia.org]. There are doubtless many more that have not yet been observed.

    • And what's the range on gravity again?

  • Let's be sensible here. We are talking about a very faint star, faint enough that we didn't bother to or even couldn't measure its path until now. Passing our solar system at the distance of a light year. Remember the "family portrait" Voyager took? Now, that's about 19 lightHOURS out. Or roughly 500 times closer.

    Do you really think a human 70,000 years ago without any astronomic tools would have noticed? Or even cared?

    • by ledow ( 319597 ) on Friday March 23, 2018 @06:01AM (#56311681) Homepage

      Some beetles navigate by the Milky Way.

      Ancient cultures all named thousands of stars and gave them associated legends, as well as navigated by them. They knew about comets, meteors, stars and galaxies.

      To be honest, they were more likely to notice something unusual - especially if it moved over time - than the average person would be today. The naked eye doesn't pick up much in a city nowadays.

      You know how I got into astronomy at age 30? I saw Venus for the very first time, while driving to Scotland for 9 hours.

      A culture that revolves around day-time and can't do anything of an evening because of insufficient light, yet being a species that naturally wakes up throughout the night - they're going to spot a red star going across the sky just like they could spot Venus doing so. And it would be a "Oh, look, that's unusual" rather than "ARGH! We're all gonna die!" purely because it wouldn't actually be that unusual or interesting to them, given the size and brightness of said star in the sky.

      • by dryeo ( 100693 )

        It was still a red dwarf that might have been barely visible and would have taken perhaps a thousand years or more to cross the sky. Very doubtful that it would have been noticed.

        • by HiThere ( 15173 )

          They wouldn't have noticed it as something unusual. It moved much too slowly for that, but the Arabs used to use one of the stars of the handle of the Big Dipper as an eye test. If you could see that there were two stars rather than one, you had sharp eyes. So it's quite possible that some of them saw it and used it in some way. But you're right that they wouldn't have thought it remarkable.

          • Sorry, that star would have been invisible except for brief flares, so it would indeed have been seen as something quite usual, if noticed. And the flares would have been brief and irregular, so someone reporting seeing them probably wouldn't have been believed. Only if a group of people say it at the same time would it have been believed. And then it would probably have been counted less remarkable than a meteor.

    • Do you really think a human 70,000 years ago without any astronomic tools would have noticed? Or even cared?

      What else were they supposed to look at?? Their women were all covered with hair.

    • It would seem unlikely. However a flood of comets or even meteors triggered by disturbing the Oort Cloud with a stellar flyby seems a possibility. I'd welcome an analysis of that potential consequence.

    • Do you really think a human 70,000 years ago without any astronomic tools would have noticed? Or even cared?

      Reading the article, while it is normally a 10th magnitude and not visible to the unaided eye, it apparently is the type of star that flares up a thousand times brighter which would put it in the range of a bight star in the sky. Given the importance of the sky, comets, stars are to primitive cultures, I'd say a new bright red star in the sky probably would be of some note to any living people at the time.

    • As long as we have recorded history, that means written, and still available to read: mankind was interested in stars. Basically everything we have in our days time in measuring of time and geometry comes from observing the stars and the sun.
      So yes: I'm pretty confident that early humans at that time cared about the sky, noticed the star, and probably made cave drawings of it.
      But: we likely never find any evidence for that.

      Mankind at that time was primitive in tools, for some reason finding stone that bleed

  • by LordHighExecutioner ( 4245243 ) on Friday March 23, 2018 @06:04AM (#56311695)
    ... and check Sun's insurance coverage for interstellar collisions. Is a repair insurance included in its policy ? Does it allow full replacement of damaged planets, or is it just offering a mere fix of broken parts ? What about the insurance coverage offered to passengers traveling either on board of planets or space veichles ?
  • by Ihlosi ( 895663 ) on Friday March 23, 2018 @06:16AM (#56311723)
    Magnitude ~11, that's really dim.
  • Incorrect reporting (Score:5, Informative)

    by Stoutlimb ( 143245 ) on Friday March 23, 2018 @06:36AM (#56311785)

    Whoever authored the science news did not check their facts. Scholz's Star had an estimated absolute magnitude of 11.4 at closest approach, which is nowhere near visible enough to be seen with the naked eye. Unless telescopes were in use 70,000 years ago, it's clear that nobody would have had any clue what was going on.

  • by ScentCone ( 795499 ) on Friday March 23, 2018 @07:06AM (#56311901)

    For perspective, the suns nearest stellar neighbor ...

    It came so close that it dislodged nearly all of our apostrophes, leaving /. editors unable to use them for 70,000 years to come.

  • by jfdavis668 ( 1414919 ) on Friday March 23, 2018 @07:42AM (#56312021)
    Recently an astrophysics professor announced the discovery of a fantastic new object he discovered on his long exposure images. He announced it to the world, but he had to send out a retraction when someone pointed out that it was the planet Mars. http://www.iflscience.com/spac... [iflscience.com]
  • Wow! Within one light year! Just 70,000 years ago. That star grazed and disturbed the Oort cloud and the Kuiper belt objects. Some of them would have settled in other gravity wells near by. But many would have fallen into the gravity well of our Sun. They will create a veritable rain of comets.

    Just brace yourselves fellas. In just 200,000 years one of these comets will strike the earth and kill 99.9% of all known species. Projections are humans will be only species left at that time subsisting on eating each other. But why engage in idle speculation?

    Since the Earth is going to be hit by a comet anyway in 200,000 years, why bother with conservation, environmentalism and organically grown tomatoes? Just enjoy life.

    • If we can't deflect a comet, or move the fucking planet in another 200,000 years, the Earth deserves another shot at producing intelligent life.
  • What nobody thought to claim this was the red comet indicating change, or the Red Lady, or something?

  • a new study suggests. In 2015

    So quite an old new study, then.

    • C'mon. We're talking about interstellar events here. It came out in the last thousand years, so it's really really new.

On a clear disk you can seek forever. -- P. Denning

Working...