
Mea Culpa: Asteroid vs Satellite - sohkamyung
http://www.syfy.com/syfywire/mea-culpa-asteroid-vs-satellite
======
privong
A related, though much closer to home, experience I have had is an airplane
flying through the field of view during a reasonably long exposure on a
galaxy. The plane's transit left two long, continuous streaks through the
image, one from each navigation light on the wing tips. The streaks had
different brightness, likely due to the transmission of the filter I was using
for red and green light. So in principle you could use knowledge of the filter
transmission curve to work out which direction the airplane flew through the
camera's field of view.

~~~
scrumper
Well you don't need to do that, because the left wing has a red light, right
has green. So as long as you're comfortable with the very reasonable
assumption that the plane isn't upside down, you know which direction it was
going.

Edit: sorry, I didn't mean to say that you can't do what you suggested, more
that if you were solely interested in direction you wouldn't need to. It'd
still be an interesting exercise!

~~~
privong
> Well you don't need to do that, because the left wing has a red light, right
> has green. So as long as you're comfortable with the very reasonable
> assumption that the plane isn't upside down, you know which direction it was
> going.

The overwhelming majority of astronomical images (i.e., those not taken with a
DSLR or other consumer-like camera) are monochrome images. So in any single
exposure you don't retrieve a RGB color image. The color images you see from
all professional and many amateur telescopes are reconstructed from multiple
exposures through different filters (e.g., the one in the syfy.com article).
So you would not see a red light and a green light – you just see two
monochrome streaks with different brightness. Planes pass through a telescope
field of view relatively quickly, so you most likely only see it in a single
exposure.

~~~
scrumper
Ah, I misunderstood your original post - didn't realize you were photographing
monochrome through a succession of filters. Thanks for the explanation.

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arjie
Man, this is a great post. I had no idea they had such information accessible
at such detail, including a sky search engine. Fantastic stuff.

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angrygoat
The way that they determined the the object was moving, and the direction, by
comparing consecutive images is exactly the way that scientists are currently
looking for a predicted dwarf planet quite far out in the solar system.

An excellent podcast ep from the Wholesome Show where the lead scientist talks
through the process - including a mass citizen science approach to
scrutinising the image series - is here:
[https://soundcloud.com/wholesomeshow/looking-for-plu-two-
a-b...](https://soundcloud.com/wholesomeshow/looking-for-plu-two-a-beer-with-
citizen-astronomer-wrangler-dr-brad-tucker)

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batbomb
If you were unanaware, most telescopes have data available online these days,
provided their data is also public and not embargoed. There's REST API you
basically do something like:

POST /tap/sync?query=select * from object a where ... HTTP/1.1

The SDSS server is probably most used.

~~~
justinclift
Hmmm... do they really take raw queries like that?

Seems like it'd be open to attack :(, unless very carefully parsed and
handled.

~~~
batbomb
Yes, there's super-subset of SQL-92 called ADQL which is ran, but no
inserts/deletes/updates are allowed. You can upload data to the services as
XML files.

~~~
justinclift
Interesting, thanks. :)

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stephengillie
I'm seeing a strange white dot float at the exact center of the browser on the
page. At first, I thought the page was being cute, with an "astronomical
artifact" of dust in the lens, but the article didn't mention it.

[https://imgur.com/a/NZL8B](https://imgur.com/a/NZL8B)

~~~
ecopoesis
It's an artifact of ad blocking.

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inetknght
It will be amazing when people start doing correlation like this across
stellar distances. Mars, just for starters.

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dclowd9901
Just recently went to the Goldendale Observatory in southern Washington, and
man was that fun. We got to look through their giant amateur telescope, as
well as do some naked eye spotting.

Go on a night when there's little moon (quarter phase?) and no weather. It's a
lot of fun, and the people working there are very charismatic.

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theandrewbailey
I looked up M77 on Wikipedia, and this image is already there, complete with
asteroid streak.

[https://en.wikipedia.org/wiki/File:Dazzling_galaxy_Messier_7...](https://en.wikipedia.org/wiki/File:Dazzling_galaxy_Messier_77.jpg)

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akavel
Apart from _" that, my friends, is science!"_, the follow-up he got is another
nice example of [https://www.xkcd.com/386/](https://www.xkcd.com/386/) —
a.k.a. "Someone's wrong on the Internet"

~~~
arcticfox
I don't think the XKCD really applies here, at least in my interpretation.
This was more like a mystery that everyone worked together to solve rather
productively.

To me, the XKCD represents pointlessly arguing over random stuff while not
making any productive points. Come to think of it, perhaps I'm falling foul of
it again as I type...

~~~
akavel
Personally, I always had (and still have) a much more positive view of the
XKCD. I believe it actually shows an interesting way how people try to make
the world better, and share their knowledge, in face of noticed errors.

I believe this mechanism can be also used with premeditation, as an
interesting way to encourage collaboration and solicit help. I seem to recall,
that in early days of Wikipedia, it was explicitly suggested that editors
should not fix small errors and typos in articles, so as to provoke newcomers
to fix them, and this way "interactively" teach them how wiki works and
provoke ("positively trick") them to start collaborating. Based on this, I'm
sometimes pondering whether conscious erroneous assertions (e.g in a blog
article) might possibly be a better way to solicit help on the Internet (e.g.
via blog comments) than explicit questions. But I'm not quite sure, and also I
can't shake the feeling that it'd be manipulative.

