Test Your Astronomy Knowledge!

[Scuba Pete]

(And no, it is not why the Earth has seasons .)

If we didn't wobble like a weeble, then our axis might possibly be VERTICAL. So I reject your premise on the grounds that the precession is exactly what GAVE us our present tilt.

 

[Mr Spinkles]

Meteor showers are caused when the Earth's orbit takes it through large clouds of dust and debris left behind by comets who's icy surfaces have been melted by the sun.

Well done!

If we didn't wobble like a weeble, then our axis might possibly be VERTICAL. So I reject your premise on the grounds that the precession is exactly what GAVE us our present tilt.

No NetDoc, tidal interactions with the Sun gave us our present tilt, and precession along with it. At any rate, Earth's seasons are contingent upon only one thing: a tilted axis. A planet with a tilted axis will experience seasons as it orbits the Sun whether or not it precesses.

Here's another one: What are the largest structures in the known universe?

 

[Scuba Pete]

What are the largest structures in the known universe?

Well, someone's ego comes to mind... but I ain't admitting nuthin'!

 

[Circle_One]

Here's another one: What are the largest structures in the known universe?

Galaxies

 

[meogi]

Here's another one: What are the largest structures in the known universe?

Super clusters?

 

[Mr Spinkles]

You're both very close! Galaxies form clusters, clusters of galaxies form super clusters, and super clusters make up things called "filaments". These are the largest structures in the universe. Filaments enclose vast areas of empty three-dimensional space in foam-like patterns.

To get a sense of scale: if the Sun were a golf ball in the middle of downtown New York City, where would the nearest neighboring star be located?

 

[HelpMe]

nice...on the sun?


what's the answer!

 

[Mr Spinkles]

if the Sun were a golf ball in the middle of downtown New York City, where would the nearest neighboring star be located?

Chicago.

True or false? If you look closely enough through a telescope, you can see the moon rotating on its axis.

 

[Scuba Pete]

NO! The moon always presents the same side to us. Wile it is indeed rotating, it appears not to!

 

[Mr Spinkles]

Excellent, NetDoc!! :woohoo: :jam:

Wow, I'm really impressed. Everyone here seems to know a lot more about astronomy than I did before I took this course.

Okay, here's a toughy: What is the most widely accepted explanation for the origin of the moon?

 

[Scuba Pete]

Spinkle spinkle little star.

Some think it a chip off of the ol' terra firma (collision).

Some think it accumulated in much the same fashion as earth.

Hey, this is kinda fun!

 

[goodjewishboy]

The explaination for the creation of the moon that I find the most interesting is the one where a planetary body about the size of mars sideswiped the young earth, the pieces of the earth that didn't just fly off into space formed the moon.

 

[painted wolf]

well the earth and the moon are different enough from one another to not have been formed at the same time or by the moon pulling off from the 'proto-earth'. However two theories are still in the running for 'best guess'. One is that the moon formed from several small planetesimals that got caught in the 'proto-earths' gravitational pull. These different bits eventually coalesed into one modern moon.
The other is the 'ejected ring theory' that goodjewishboy mentions. A large something hit the early earth. (though just how big is anyones guess) This goes to explain some of the different make up as the early earth had long enough for some of its elements to settle tword the core and thus miss being taken up by the impact. The moon would then have formed from the ejected ring of material that got thrown up from the collision.

none of the theories are decided uppon last I heard but the 'ejected ring theory' is currently the most popular.

wa:do

 

[Mr Spinkles]

Wow! Great job everyone--I couldn't have said it better than painted wolf.

Hmmm....I'm going to have to think hard about some questions that might actually stump people (without searching on Google, of course ).

 

[Mr Spinkles]

True or False: the heliocentric model of the universe proposed by Copernicus more accurately predicted the motions of the planets than the geocentric model.

 

[linwood]

True or False: the heliocentric model of the universe proposed by Copernicus more accurately predicted the motions of the planets than the geocentric model.

False.

While Copernicus had the relation of planets to the sun down better he had the motion of them just about the same (circular) where they really rotate in an oval pattern.

Yes..yes..?

No?

Maybe?

How wrong am I?

 

[Mr Spinkles]

PERFECT, you're absolutely correct!!! *edit: replace "oval" with "elliptical" if you want to get nit picky*

Wow, I am REALLY impressed with everyone's astronomy knowledge!

What causes the volcanism on Jupiter's moon Io?

 

[Scuba Pete]

Gravitational pull from Jupiter would be my guess.

 

[Mr Spinkles]

Good guess.

The volcanism on Io is caused by "tidal heating". The combination of Jupiter's gravitational pull and the gravitational pull of some of the neighboring moons (Europa, Callisto, and Ganymede) stretch and squeeze Io's interior. This generates a huge amount of heat, which travels outward to the surface as volcanism.

 

[Scuba Pete]

I think I gleaned that from reading tons of Science Fiction when I was younger.