5 ms·

When you look at the trajectory that this object took through the solar system, coming within .14 AU of earth, you really have to wonder; what are the chances t

When you look at the trajectory that this object took through the solar system, coming within .14 AU of earth, you really have to wonder; what are the chances that it was a random flyby?

deleted 8y ago
[deleted]
vertline3 8y ago
Well, I think there could be lots of rocks but they are hard to see.
InclinedPlane 8y ago
You have to consider instead the probability of detecting such objects that don't come very close to Earth. And that probability is actually pretty low (currently), so the proximity tells us very little beyond some general estimate of how common such objects are.
- jnicholasp 8y ago
  And in a similar vein, we have only very recently become able to detect (some) objects such as this one, and shortly after we gained the ability to spot things like this, we spotted this one. It at least allows the possibility that events like this are not incredibly rare, and we just haven't been able to perceive them until now.
  - simonh 8y ago
    Plus, it's not as if 0.14 AU (it was actually further than that according to Wikipedia)) is all that close, it was still well over 20 million km away or over 50 lunar orbital radii. It just sounds small when you write it as 0.14 because it's a small fraction of an AU, but an AU is freaking huge. If we sent a probe to Jupiter and it only got within 0.14 AU I can't see that being considered much of a success.
Afforess 8y ago
>what are the chances that it was a random flyby? ~99.9̅% chance of being random. Absent any sort of evidence, it was a rare, meaningless event. The law of large numbers, however, suggests that rare events occur more frequently than you'd expect. E.g 1 in 1000 year floods could occur 3 times in a decade, since each event is statistically independent from others.
- adwn 8y ago
  > ~99.9̅% chance of being random. Where did you get that number from? Because it looks like you made it up.
  - Retric 8y ago
    The odds of any one ticket being the wining lottery ticket is very low. However, with huge jackpots the odds that someone will win are very high. In other words the odds that that specific rock get’s that close is low. But, if we only observe rocks close to us then the odds that we will see a rock close to us depends more on the number of rocks than the low odds for anyone rock. More generally becase we notice unusual events more than common ones you need to consider all possible unusual events you would notice not just the odds of that specific event.
- lifeformed 8y ago
  99.9̅% == 100%
  - dEnigma 8y ago
    Good catch. I didn't even notice this while reading the grandparent comment. But I've seen people debate this fact, or rather the fact that 0.9̅=1, for days and weeks on the internet.
  - Roritharr 8y ago
    Wow, you just pushed me and my girlfriend into a heated debate regarding this. Is there a list anywhere of similar unintuitive math properties/facts?

When you look at the trajectory that this object took through the solar system, coming within .14 AU of earth, you really have to wonder; what are the chances that it was a random flyby?

deleted 8y ago

[deleted]

vertline3 8y ago

Well, I think there could be lots of rocks but they are hard to see.

InclinedPlane 8y ago

You have to consider instead the probability of detecting such objects that don't come very close to Earth. And that probability is actually pretty low (currently), so the proximity tells us very little beyond some general estimate of how common such objects are.

jnicholasp 8y ago
And in a similar vein, we have only very recently become able to detect (some) objects such as this one, and shortly after we gained the ability to spot things like this, we spotted this one. It at least allows the possibility that events like this are not incredibly rare, and we just haven't been able to perceive them until now.
- simonh 8y ago
  Plus, it's not as if 0.14 AU (it was actually further than that according to Wikipedia)) is all that close, it was still well over 20 million km away or over 50 lunar orbital radii. It just sounds small when you write it as 0.14 because it's a small fraction of an AU, but an AU is freaking huge. If we sent a probe to Jupiter and it only got within 0.14 AU I can't see that being considered much of a success.

Afforess 8y ago

>what are the chances that it was a random flyby? ~99.9̅% chance of being random. Absent any sort of evidence, it was a rare, meaningless event. The law of large numbers, however, suggests that rare events occur more frequently than you'd expect. E.g 1 in 1000 year floods could occur 3 times in a decade, since each event is statistically independent from others.

adwn 8y ago
> ~99.9̅% chance of being random. Where did you get that number from? Because it looks like you made it up.
- Retric 8y ago
  The odds of any one ticket being the wining lottery ticket is very low. However, with huge jackpots the odds that someone will win are very high. In other words the odds that that specific rock get’s that close is low. But, if we only observe rocks close to us then the odds that we will see a rock close to us depends more on the number of rocks than the low odds for anyone rock. More generally becase we notice unusual events more than common ones you need to consider all possible unusual events you would notice not just the odds of that specific event.
lifeformed 8y ago
99.9̅% == 100%
- dEnigma 8y ago
  Good catch. I didn't even notice this while reading the grandparent comment. But I've seen people debate this fact, or rather the fact that 0.9̅=1, for days and weeks on the internet.
- Roritharr 8y ago
  Wow, you just pushed me and my girlfriend into a heated debate regarding this. Is there a list anywhere of similar unintuitive math properties/facts?