[HN Gopher] Astronomers Discover Closest Black Hole to Earth
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Astronomers Discover Closest Black Hole to Earth
Author : tannhaeuser
Score : 65 points
Date : 2022-11-05 08:45 UTC (14 hours ago)
(HTM) web link (noirlab.edu)
(TXT) w3m dump (noirlab.edu)
| habibur wrote:
| The numbers : Size : 10 x sun's mass.
| Distance : 1600 LY. Previous closest had been : ~5000 LY.
|
| Discovered by calculating the velocity of a rotating run around
| it.
|
| For comparison, a star going supernova to harm earth has be to
| within 70 LY.
| dustingetz wrote:
| how wide is the event horizon and how close can a current gen
| spaceship get before being gravitationally bound?
| Hobert wrote:
| About 1600LY...
| derjames wrote:
| Schwarzschild radius ~28 km
| https://en.wikipedia.org/wiki/Gaia_BH1
| sabujp wrote:
| tx this is what i was looking for, also this agrees
| https://www.omnicalculator.com/physics/schwarzschild-radius
| 867-5309 wrote:
| >For distance comparison, a star going supernova to harm earth
| has be to within 70 LY.
|
| what is that based on?
| Smashure wrote:
| I don't know where they got that number from. It's depending
| on a multitude of factors like, type of supernova and
| orientation of the supernova (like if we're in line for a
| gamma ray burst)
|
| *edit
|
| For anyone interested in this topic I suggest Phil Plait's
| book in the subject
| bilsbie wrote:
| Any risks of that within 70ly?
| ceejayoz wrote:
| Not at the moment. IK Pegasi is the closest candidate, at
| about 2x that distance. Would be a hell of a show, though.
|
| https://en.wikipedia.org/wiki/Near-Earth_supernova
| dtgriscom wrote:
| Does that make the assumption that the nova's energy is
| distributed evenly? Because I believe there are gamma ray
| bursts that are quite directional, and can if pointed at us
| cause harm far further than that. (IANA astronomer...)
| colechristensen wrote:
| No, a gamma ray burst pointed at us within several thousand
| light years could cause a mass extinction event. There are a
| couple of candidates for mass extinctions which _might_ have
| been GRBs. They are very rare though.
| aaron695 wrote:
| midislack wrote:
| * Closest KNOWN black hole to Earth. Not the closest one, period.
| JoeAltmaier wrote:
| Except maybe a tiny one in the middle of the Sun or even the
| Earth?
| _justinfunk wrote:
| Closet black hole to earth so far
| dylan604 wrote:
| Right. Just wait until they turn on the Large Hadron Collider
| and it starts to create black holes that will swallow the
| earth! /s
| [deleted]
| [deleted]
| spuz wrote:
| > Astronomers' current models of the evolution of binary systems
| cannot fully explain how the peculiar configuration of the Gaia
| BH1 system came about, because the original star that later
| became this black hole should have been at least 20 times more
| massive than our Sun. This means that it would have lived only a
| few million years. If both stars formed at the same time, this
| massive star would have rapidly become a supergiant, inflating
| and engulfing the other star before it had time to become a
| proper main-sequence star, burning hydrogen just like our own
| Sun.
|
| > It's not entirely clear how the solar-mass star survived that
| episode, ending up an apparently normal star, as observations
| indicate. All theoretical models that allow for this survival
| predict that the solar-mass star should be in a much tighter
| orbit than is actually observed.
|
| Should this last sentence actually read: "All theoretical models
| that allow for this survival predict that the solar-mass star
| should be in a much wider orbit than is actually observed."?
| fmblwntr wrote:
| No, from the abstract of the paper "The orbital period, 185.6
| days, is longer than that of any known stellar mass black hole
| binary. [...] How the system formed is uncertain. Common
| envelope evolution can only produce the system's wide orbit
| under extreme and likely unphysical assumptions"
|
| See section 8.4 for details: https://arxiv.org/abs/2209.06833
| But basically the idea is that they are assumed to have
| interacted in the past (based on the distance), and given that,
| all current models of such interactions would predict a very
| tight final orbit for the solar mass star.
| Broken_Hippo wrote:
| Maybe, but I'll give some slack here. Translations aren't
| perfect and maybe it read better before translation.
| narag wrote:
| It's the same in the Spanish version.
| tete wrote:
| Why? It's just the closest detected one.
| Broken_Hippo wrote:
| Ok. So?
|
| The issue here is that I don't read spanish. I used a
| translator - google, actually. And I know painfully well
| that sometimes translations are clunky even when they are
| generally good. I don't have a lot of experience between
| Spanish and English, but I do with Norwegian-English, and
| those are both germanic languages and often translate
| decently.
|
| But not always. Some things are just messed up. Some things
| don't translate word-for-word simply because folks express
| things differently.
|
| So yeah, it might be weird in English. Might not be in
| Spanish, though.
| abhaynayar wrote:
| I guess I was wrong then.
|
| https://news.ycombinator.com/item?id=31381169
| Eupraxias wrote:
| They calculate that it is 1600 light years away. So, unless you
| were lighting your childhood campfires 1600 years ago, that
| light still has a little way to go.
| [deleted]
| PartiallyTyped wrote:
| Unless there's proof that the last planet is indeed... well...
| a planet; we that can't be ruled out just yet :D
| amacbride wrote:
| English version from the same site:
| https://noirlab.edu/public/news/noirlab2227/?nocache=true
| Simon_O_Rourke wrote:
| Thanks guys, another worry to add to the list of climate change,
| potential right-wing insurrection and the health effects of Taco
| Bell.
| westurner wrote:
| Micro black hole > Black holes in quantum theories of gravity
| https://en.wikipedia.org/wiki/Micro_black_hole#Black_holes_i...
|
| Virtual black hole
| https://en.wikipedia.org/wiki/Virtual_black_hole
|
| Timeline of gravitational physics and relativity
| https://en.wikipedia.org/wiki/Timeline_of_gravitational_phys...
|
| - [ ] Superfluid Quantum Gravity
|
| -- [ ] GR + Bernoulli's re: Dark Matter/Energy: Fedi (2017),
|
| "What If (Tiny) Black Holes Are Everywhere?"
| https://youtu.be/srVKjWn26AQ
|
| > _Just one Planck relic per 30km cube, and that's enough to make
| up most of the mass in the universe_
|
| Quantum foam: https://en.wikipedia.org/wiki/Quantum_foam
| delta_p_delta_x wrote:
| Actual article: https://doi.org/10.1093/mnras/stac3140
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(page generated 2022-11-05 23:02 UTC)