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Anyone else realize how random it is to have a (potential) planet orbit a black hole in such a specific way that it eclipses it ...> when viewed from fkn Earth.

Anyone else realize how random it is to have a (potential) planet orbit a black hole in such a specific way that it eclipses it ...> when viewed from fkn Earth.. 20 something million light years away?? lol . nuts Same kinda 'randomness' provides for near-perfect (100%) solar-eclipses from Earth's surface .. Meaning if the Moon orbited any further or closer... it would not have the angular diameter from E's surface to perfectly block-out the angular diameter of the sun as viewed from Earth

TheOtherHobbes 6y ago
I'm not sure the first is all that random. There seem to be a lot of planets and black holes likely aren't all that rare. The second is a stupendous coincidence, and if the Earth ever becomes part of a galactic civilisation we'll have a very impressive draw for alien tourists. Of course it might also be a business card left by the entities that engineered this reality but... probably not.
- saagarjha 6y ago
  Sadly this particular tourist attraction will only be interesting for the next couple hundred million years, after which the moon will drift away too far to make it work anymore :(
  - jahnu 6y ago
    Doesn't that suggest that lots of other moons spend some period of their lifetime in this perfect eclipse zone?
em3rgent0rdr 6y ago
(some very large number of stars) * (some rare possibility for each star) => a potentially non-too-rare number.
- dash2 6y ago
  But it's still a huge coincidence for us. If (if!) there are millions of civilizations in the galaxy, presumably only a very few experience total eclipses.
  - goatlover 6y ago
    If there were millions of civilizations in the Milky Way, we would already know it.
    - sweetheart 6y ago
      Not if you subscribe to the Dark Forest theory ;)
dredmorbius 6y ago
Multiple comparisons fallacy, related to the Birthday paradox. Low probability * quadrillions of possible instances === near certainty. There are ~100 billion solar masses (roughly; stars) in a single galaxy. There are roughly 100 billion galaxies in the observable universe. The Hubble Deep Field image has ~3,000 galaxies, looking at an empty spot of sky 1/10th the width of the full Moon. A later more intensive image within this revealed 10,000 galaxies. 100 billion * 100 billion is 10^22 stars, 10,000 billion billions. That's about a 100 billion stars for every person now living by rough order-of-magnitude maths. The number of black holes per galaxy is likely at least in the thousands, and by models as high as 100 million (plus or minus an order of magnitude0 per galaxy (see; https://www.forbes.com/sites/startswithabang/2017/06/03/ask-ethan-how-many-black-holes-are-there-in-the-universe/ https://www.forbes.com/sites/startswithabang/2017/06/03/ask-...) 10^11 * 10^8 == 10^19, or 10 billion billion black holes to observe. The likelihood that a planet might orbit one such black hole at an angle creating a transit visible from Earth is not at all low. And having observed a rare event to have occurred, that is, with a prost hoc probability of one, declaring it improbable is a misuse of statistics. https://en.wikipedia.org/wiki/Birthday_problem https://en.wikipedia.org/wiki/Birthday_problem https://theconversation.com/paradoxes-of-probability-and-other-statistical-strangeness-74440 https://theconversation.com/paradoxes-of-probability-and-oth... https://en.wikipedia.org/wiki/Hubble_Deep_Field https://en.wikipedia.org/wiki/Hubble_Deep_Field https://en.wikipedia.org/wiki/Hubble_Ultra-Deep_Field https://en.wikipedia.org/wiki/Hubble_Ultra-Deep_Field

TheOtherHobbes 6y ago

I'm not sure the first is all that random. There seem to be a lot of planets and black holes likely aren't all that rare. The second is a stupendous coincidence, and if the Earth ever becomes part of a galactic civilisation we'll have a very impressive draw for alien tourists. Of course it might also be a business card left by the entities that engineered this reality but... probably not.

saagarjha 6y ago
Sadly this particular tourist attraction will only be interesting for the next couple hundred million years, after which the moon will drift away too far to make it work anymore :(
- jahnu 6y ago
  Doesn't that suggest that lots of other moons spend some period of their lifetime in this perfect eclipse zone?

em3rgent0rdr 6y ago

(some very large number of stars) * (some rare possibility for each star) => a potentially non-too-rare number.

dash2 6y ago
But it's still a huge coincidence for us. If (if!) there are millions of civilizations in the galaxy, presumably only a very few experience total eclipses.
- goatlover 6y ago
  If there were millions of civilizations in the Milky Way, we would already know it.
  - sweetheart 6y ago
    Not if you subscribe to the Dark Forest theory ;)

dredmorbius 6y ago

Multiple comparisons fallacy, related to the Birthday paradox. Low probability * quadrillions of possible instances === near certainty. There are ~100 billion solar masses (roughly; stars) in a single galaxy. There are roughly 100 billion galaxies in the observable universe. The Hubble Deep Field image has ~3,000 galaxies, looking at an empty spot of sky 1/10th the width of the full Moon. A later more intensive image within this revealed 10,000 galaxies. 100 billion * 100 billion is 10^22 stars, 10,000 billion billions. That's about a 100 billion stars for every person now living by rough order-of-magnitude maths. The number of black holes per galaxy is likely at least in the thousands, and by models as high as 100 million (plus or minus an order of magnitude0 per galaxy (see; https://www.forbes.com/sites/startswithabang/2017/06/03/ask-ethan-how-many-black-holes-are-there-in-the-universe/ https://www.forbes.com/sites/startswithabang/2017/06/03/ask-...) 10^11 * 10^8 == 10^19, or 10 billion billion black holes to observe. The likelihood that a planet might orbit one such black hole at an angle creating a transit visible from Earth is not at all low. And having observed a rare event to have occurred, that is, with a prost hoc probability of one, declaring it improbable is a misuse of statistics. https://en.wikipedia.org/wiki/Birthday_problem https://en.wikipedia.org/wiki/Birthday_problem https://theconversation.com/paradoxes-of-probability-and-other-statistical-strangeness-74440 https://theconversation.com/paradoxes-of-probability-and-oth... https://en.wikipedia.org/wiki/Hubble_Deep_Field https://en.wikipedia.org/wiki/Hubble_Deep_Field https://en.wikipedia.org/wiki/Hubble_Ultra-Deep_Field https://en.wikipedia.org/wiki/Hubble_Ultra-Deep_Field