What is a Black Hole?

"A black hole is one of the strangest objects in space. It is an area in space where gravity is so strong that even light cannot escape from it. Since light cannot escape from a black hole, it appears black. Light can travel faster than anything we know of - at a speed of 186,000 miles (300,000 kilometers) per second. If light cannot escape from a black hole, nothing else that we know of can. A black hole is not really a hole and it is not empty. It is filled with a lot of material crammed into an extremely small space. This is what gives a black hole its super strong gravity. The term black hole is used because these objects look like black holes in space - since they put out no light." (http://coolcosmos.ipac.caltech.edu/cosmic_kids/AskKids/blackhole.shtml)

This is good background information on black holes:
http://www.kidsastronomy.com/black_hole.htm

http://coolcosmos.ipac.caltech.edu/cosmic_kids/AskKids/blackholes.shtml

What happens if I get sucked into a black hole?

This is another great question I have been hearing a lot. I think everyone is pretty safe from black holes, but theoretically....

If you were sucked into a black hole, your energy would convert into heat, and your body would reach incredibly high temperatures. As your superheated self fell closer to the center of the black hole, you would cross a threshold called an event horizon. The event horizon is like a point of no return. After the event horizon, any light from your heat would no longer be visible. Your would collapse into the center of the black hole, which called a singularity. The singularity is a dimensionless (not 1-D, 2-D, 3-D, 4-D, etc...) object of infinite density.

Long story made short: You would be squashed!!! Well, squashed into a dimensionless object of infinite density with no light. Try drawing a picture of that!

Here are the sites I used to research this question.
http://kids.yahoo.com/science/space/article/blackhole
http://starchild.gsfc.nasa.gov/docs/StarChild/universe_level1/black_holes.html

Will looking at a solar eclipse make me blind??

This is a question I keep hearing in class. At this NASA website, the experts set the record straight. Can looking at a solar eclipse lead to permanent vision loss? YES. Do not look directly at a solar eclipse! It is safe, however, to look with the naked eye only during the short phase of totality (a total solar eclipse) when the whole moon is blocking the sun. In partial eclipse or any other time, it is very important to use eye protection!!

http://eclipse.gsfc.nasa.gov/SEhelp/safety.html

At this website, Mr. Eclipse explains more about how to protect your eyes.

http://www.mreclipse.com/Totality2/TotalityCh11.html

Even staring at the Sun on a regular day is dangerous. Be careful!

Spring Tide vs. Neap Tide

A neap tide occurs only twice a month, during the first and third quarter moon. A neap tide has the lowest high tides and highest low tides of the month. The tidal range (distance on the beach between high and low tide) is at its lowest.

A spring tide also occurs twice a month, but at the full and new moon. A spring tide has the largest tidal range of the month, so the distance between high and low tide is the greatest. This means higher high tides and lower low tides.

The pattern of the lunar month's spring and neap tides is nicely animated at this site: http://oceanservice.noaa.gov/education/kits/tides/media/supp_tide06a.html

Tides?? Here are some helpful resources.

The Moon's gravitational pull on Earth causes tides! What is a tide? Check out the videos at these links:

http://videos.howstuffworks.com/hsw/10000-the-moon-tides-video.htm

This page also includes many different videos about the moon that answer some interesting questions such as 'How did the Moon form?'

The second video is from NASA:
http://www.nasaimages.org/luna/servlet/detail/NVA2~15~15~53648~124808:What-is-a-Tide

The animation at the link below illustrates how high and low tides work. There are about two high tides and two low tides every day.
http://science.nasa.gov/headlines/images/missingtides/dissipation.gif

Earth's Seasons: Who wants to be a millionaire??

Here is an online game you might like:

http://www.quia.com/rr/37464.html?AP_rand=672856361

Learn about this little guy!

http://www.washingtonpost.com/wpdyn/content/article/2009/03/24/AR2009032403517.html?hpid%3Dartslot&sub=AR

Diagram: Why do we always see the same part of the Moon?

Source: http://startswithabang.com/?p=398

Why do we always see the same part of the Moon?

Even as the Moon changes phases throughout the month, we are always seeing the same face (the half facing us) of the moon! If you don't believe me, take a long look at this photo series (above) of the Moon over one month. This picture was copied from: http://startswithabang.com/.

How does that work? The moon rotates on its axis, just like Earth's rotates, so why aren't we seeing the whole sphere??

The Answer: The moon rotates once in 29.5 days and also orbits Earth once every 29.5 days. Because the rates of rotation and revolution are the same, the moon does APPEAR to rotate to an observer on Earth. Outside observers, however, would be able to see the moon rotating when observing the Sun, Moon, Earth system.

Here's one explanation: http://www.badastronomy.com/bad/misc/moon_spin.html

And here's another: http://startswithabang.com/?p=398

Here's a fun way to remember this:

Oh, glorious Moon!

As I gaze on your face

it comes to my mind

That never shall I gaze

On your glorious behind.

--Anonymous

Moon Phase Diagram and Animation

Here is a great diagram of how Moon phases work. This diagram was copied from Nick Strobel's Astronomy Notes.Go to his site at http://www.astrono%20mynotes.com/for the updated and corrected version.

Want to practice today's new vocabulary and test your knowledge of the Moon's phases as it completes one orbit (29.5 days) around Earth?

Here is an excellent animation of both the view of the moon from Earth and a diagram of the moon's position in relation to the Earth and Sun.

Check it out!

http://www.sumanasinc.com/webcontent/animations/content/moonphase.html