Week 5 Review

Week 5 and the weather continues to be very challenging. It has been wet and windy, but we might get a chance to look at the sky tonight.

This week we discussed the moon, craters and satellites, manmade or natural. The movie, If we had No Moon fascinated me the most. The most current view of how the Moon became is the theory that the Earth was impacted by a Mars size planet referred to as Orpheous or Theia. I wish the Greeks would get their story straight. Apperently Orpheus is the son of Calliope and either Oeagrus or Apollo… common you guys, this is a myth, one would think you could get it straight – use DNA to figure it out. Anyway, Orpheus slammed into Earth more than 4 billion years ago when things still were hot and soft. The trajectory of Orpheus was shallow enough so Orpheus kind of ricochet off the Earth's surface flew back into space re-coalesced and fell back onto Earth. According to Dr. Robin Canup this and only this scenario puts sufficient stuff into an orbit outside the Roche radius to form the Moon. Well, if that is what they say, I guess they know what they are talking about. I certainly do not have a better theory but… Whenever there is a scenario that indicates to be unique and inimitable I get suspicious. Orpheus had to come in on a precise angle, bounce off the Earth, enough to get stuff back into space but not so far so as to be outside the Rosh radius, other ways it would not fall back onto Earth but some of the stuff had the be outside the Rosh radius to form the Moon… But what the heck, they know what they talk about. Watch the movie, and decide for yourself. (By the way, click on the Pictures to see full size)

I just discovered the coolest web site in respect to astronomy. You got to check this out: Jet Propulsion Laboratory. There is so much stuff there, you will get lost for days. The best part I discovered so far is a Java aplet that shows an interactive model of the planetary system plus many of comets and asteroids. The best way to get to that page, follow this link to Solar System Bodies. From here, click on an option, either Comets, Asteroids or Meteor Streams. From here start exploring. Just in case you get lost, here is a direct link to the 1P/Halley Comet.
Enjoy the journey, don't get lost!

Last but not least, this pictures is not necessarily a astronomy picture, but it was captured by NASA's Terra spacecraft so it is kind of space related. This is awful! This oil leak disaster 50 miles off the Louisiana coast is now bigger than the Exxon Valdez eco disaster in Alaska in 1989. Look at the size of this oil slick. To learn more, follow this link.  If there is something I have learned so far in this astronomy class, we won't be leaving this planet any time soon, so let's take care of it and let's stop messing it up!