See, that didn't take long.

I have assumed the binary star system, since this is the object and not one of the two stars, taken as a whole (ie orbital dimension) would measure less than 30 arcminutes if viewed from 1 a.u.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

George,

I didn't consider the separation between the two stars, the value of which I have not been able to determine, to be an object.

Dave Mitsky

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Chance favors the prepared mind.
De gustibus non est disputandum.
Never attribute to malice that which can be adequately explained by stupidity.

Is it a polar or intermediate polar?

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18. Yes.

__________________
Chance favors the prepared mind.
De gustibus non est disputandum.
Never attribute to malice that which can be adequately explained by stupidity.

I think we are suppose to ask Yes/No questions. However, you may be on to something big here, judging by the wink. Perhaps this is a double binary.

__________________
Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

George,

The wink was to underscore the fact that the answer to the question was yes for one of the choices.

__________________
Chance favors the prepared mind.
De gustibus non est disputandum.
Never attribute to malice that which can be adequately explained by stupidity.

Nuts, the alternative would have been better. That would have made quite an interesting double.

I'll guess it is an intermediate polar, right?

__________________
Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

__________________
Chance favors the prepared mind.
De gustibus non est disputandum.
Never attribute to malice that which can be adequately explained by stupidity.

1. The object is not bigger than a cubic light year.
2. In the strictest sense of the term, it would not be greater in apparent size than 30' at 1 a.u., to the best of my knowledge.
3. Yes, the "object" is spherical.
4. It does not lie within 1 light-year of the Sun.
5. Nuclear fusion is currently occuring and has occurred in the past.
6. A variable star is correct.
7. It is a binary star.
8. The object is the binary star system itself, not one of the stars alone.
9. Fusion is not taking place in both of them.
10. The binary does not contain a black hole.
11. Yes, it is an X-ray binary.
12. One of the pair is not a massive star.
13. Yes, it's a denizen of the Milky Way.
14. The binary in question is not part of a globular cluster.
15. It is not a microquasar.
16. It is not a soft x-ray transient.
17. The system does not contain a neutron star.
18. Yes, it is a polar or intermediate polar?
19. No, it is not an intermediate polar (thus, it is a polar).

It is an eclipsing variable polar x-ray binary without a black hole or neutron star member, and located in our Milky Way but not in a globular cluster. It is not a microquasar, nor a soft x-ray transient. Only one star has active fusion, thus it is likely a white dwarf for the primary.

One question left. No pressure.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

As we have just one question left, I might as well take a swipe:

Is it AM Herculis?

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20. It is indeed AM Herculis.

http://www.aavso.org/vstar/vsots/0601.shtml

http://www.daviddarling.info/encyclo...ulis_star.html

http://physci.llnl.gov/Research/Cata...he_polars.html

Congrats! You're up, Eroica.

Dave Mitsky

__________________
Chance favors the prepared mind.
De gustibus non est disputandum.
Never attribute to malice that which can be adequately explained by stupidity.

Phew!

I think I'll stick to the Twenty Questions format:

What celestial object am I thinking of?

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You are thinking of AM Herculis, 'cause that was a great pull-out!! Nice one, Eroica!

But, you are also thinking of something else, apparently.

Is it larger than a proplyd?

[Added: Nice one Dave, that seems to be the binary that established polars.]

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

The Voyager spacecraft contained a gold record with the sounds and images of Earth in case it gets picked up by another civilisation. Included was a very famous Rock & Roll song from the 1950's. What was it?

"Your're so wrong the light from 'wrong' hasn't even reached you yet" ... (old proverb I just made up.)

Thanks, George.

1: No, it is not larger than a protoplanetary disc.

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Interesting question, AstroDave, and welcome to the game. But you must answer the current question correctly before you get to submit a question yourself.

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Oh, I see .... OK then, let's just consider it a project in waiting.

2. Is nuclear fusion happening there?

AstroDave - welcome to the game. The Rock'n'Roll peace is "Johnny be Goode" by Chuck Berry. Since we have discovered the 20 questions format, we tend to spend a lot of time on one riddle - so I didn'T want to keep you waiting that long... This is a version I like lot...

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Non sunt multiplicanda entia praeter necessitatem.

Welcome aboard, AstroDave.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

2: No, nuclear fusion is not occurring there.

No, it is not larger than a protoplanetary disc.

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- Learn a lot teaching others.