
A 5km Asteroid May Briefly Occult the Brightest Star in the Night Sky - rbanffy
https://arstechnica.com/science/2019/02/a-small-asteroid-may-briefly-blot-out-sirius-monday-night/
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caf
There is a flying telescope built on a 747SP, a joint enterprise of NASA and
the German space agency, called SOFIA. It is able to fly to see events like
this that can only be observed from a limited range of locations.

[https://www.abc.net.au/news/2019-02-01/sofia-flying-
telescop...](https://www.abc.net.au/news/2019-02-01/sofia-flying-telescope-
occultation-chasing-shadow-titan/10635802)

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sxcurry
I think SOFIA is used mainly for Infrared astronomy. By flying above most of
the atmosphere it can observe in the infrared, where Earth based telescopes
are severely limited.

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goodcanadian
The purpose of SOFIA is to fly above as much of the water vapour in the
atmosphere as possible to do astronomy in the far infrared and terrahertz
regimes: frequencies that are absorbed by water. Near infrared astronomy can
easily be done from the ground. As the grandparent mentioned, it is also used
as a mobile telescope to do observations of stellar occultations. The purpose
of this is to get a measure, for example, of Pluto's atmosphere as it passes
in front of a star. I doubt it would be used for an occultation by an asteroid
as you wouldn't gain anything by the measurement.

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jessriedel
I suppose you could get information about the asteroid's shape?

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jcims
Indeed they do. You can see some of the analysis here [1], by calculating the
time period of the occultation and the transit location of the star across the
body of the asteroid. I don't know how they account for rotation or how they
so precisely know where the asteroid will be relative to the star.

[1]
[https://www.google.com/search?tbm=isch&sa=1&q=asteroid+shape...](https://www.google.com/search?tbm=isch&sa=1&q=asteroid+shape+occultation)

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taneq
“Look,” whispered Chuck, and George lifted his eyes to heaven. (There is
always a last time for everything.)

Overhead, without any fuss, the stars were going out.

~~~
danielvf
From “The Nine Billion Names of God“ by [edit, wrong: Isaac Asimov].

Almost made me cry the first time I read those last lines.

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my_first_acct
Indeed from "The Nine Billion Names of God", but this classic of SF was by
Arthur C. Clarke, not Isaac Asimov.

However, Isaac Asimov did write "Nightfall", another classic, which describes
what happens when, as the result of an eclipse, the stars come out, rather
than go out...

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ridgeguy
"Nine Billion..." is a great short read on the perils of being on-site IT
support.

...and 'Nightfall' is for certain an example of the perils of astronomy.

Loved them both when I read them as a kid.

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ChuckMcM
That is a Sirius total eclipse :-)

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bch
s/occult/occlude/g

Edit: Wow, see below - today I learned something.

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doktrin
You were technically wrong, but good luck ever using 'occult' as a verb
anywhere but intellectual and special interest message boards.

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bch
The best kind of wrong? :)

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pts_
Interestingly Sirius' illustration on the page seems to be moving due to
optical illusion.

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torgian
Damned occults gotta ruin my stargazing too?!

