<p>Recently, the fly-through the Solar system of the inter-stellar object (ISO) `Oumuamua caused quite a stir in the astronomy community. I wonder whether there are reliable estimates for the (local) number density of such objects. Such estimates could be based on the `Oumuamua event (when they are necessarily rather crude owing to very low-number statistics) or on any other constraints.
A related question is: how close to Earth must an ISO pass to be detected with today's instruments, or 10, 25, 50 years ago?</p>

CC BY-SA 4.0
2019-06-21T16:30:36.547Z
Estimates for LSST (8.4m survey telescope, 6.5m effective area) are ~1 interstellar object detected per year with considerable uncertainty
astrosnapper
CC BY-SA 4.0
2019-06-21T19:08:18.890Z
@astrosnapper That's not at all what I asked, though somewhat related.
Walter
CC BY-SA 4.0
2019-06-21T19:28:32.143Z
@astrosnapper do you have a reference for that?
Walter
CC BY-SA 4.0
2019-06-22T21:02:10.027Z
@mistertribs I indeed missed that in my research (I formulated the question later and differently from my searches). I think this paper actually gives an answer to my question. So, if you upgrade your comment to an answer (with more than just the link, though), I'm prepared to accept it.
Walter
CC BY-SA 4.0
2019-06-22T21:13:07.110Z
@mistertribs Though you may also see this https://ui.adsabs.harvard.edu/abs/2017AJ....153..133E/abstract (quoted from the paper you dug up), which prior to the detection of 'Oumuamua estimated the density 1000 times smaller.
Walter
<asteroids><oumuamua>
What's the number density of `Oumuamua like objects?
Walter
# What's the number density of `Oumuamua like objects?

(Asked by: username_0 on 2019-06-21)

Recently, the fly-through the Solar system of the inter-stellar object (ISO) `Oumuamua caused quite a stir in the astronomy community. I wonder whether there are reliable estimates for the (local) number density of such objects. Such estimates could be based on the `Oumuamua event (when they are necessarily rather crude owing to very low-number statistics) or on any other constraints.
A related question is: how close to Earth must an ISO pass to be detected with today's instruments, or 10, 25, 50 years ago?

**Tags:** asteroids, oumuamua

> **Comments:**
> **username_1**: Estimates for LSST (8.4m survey telescope, 6.5m effective area) are ~1 interstellar object detected per year with considerable uncertainty  
> **username_0**: @username_1 That's not at all what I asked, though somewhat related.  
> **username_0**: @username_1 do you have a reference for that?  
> **username_0**: @mistertribs I indeed missed that in my research (I formulated the question later and differently from my searches). I think this paper actually gives an answer to my question. So, if you upgrade your comment to an answer (with more than just the link, though), I'm prepared to accept it.  
> **username_0**: @mistertribs Though you may also see this https://ui.adsabs.harvard.edu/abs/2017AJ....153..133E/abstract (quoted from the paper you dug up), which prior to the detection of 'Oumuamua estimated the density 1000 times smaller.  

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## 0 answers

