Sorry, wholly uninspired today. Between a busy day (trying to write a talk and trivia quiz) and the coughy-sneezy lurgy someone gave me despite my best efforts, I'm a bit worn out. Here's the pottage (lentil stew) other half made for me :)
BTW my talk is for some schoolkids coming to our astronomy outreach activities on Wednesday. If you don't know, 5th/6th June is the last chance to see a transit of Venus in your lifetime! You can see a nice video about it here (4 mins): http://www.youtube.com/watch?feature=player_embedded&v=ehHY9fTrb7Q
Thanks for the Video link, I found that very interesting. My friend has just bought a Telescope so I will be passing that on, Hope you recover from your lurgy in time to see the transition. :)
You obviously know more than me but if the last transit was 2004 why is it so close to this one if it is going to be the last one in our lifetime. My lass keeps belting on about the end of the world and when I thought about that I thought OH No! The dude in the video sounded like he was doing a public service announcement as well!
@teamoliver It's all a bit complicated, but comes down to two things: Venus's year is different to Earth's, so they only line up every 1.6 years. BUT Venus's orbit is inclined slightly relative to Earth's, so most of the time when they align, Venus appears above or below the Sun in the sky. There is only about a 10-year window at each side of the orbits where they cross. In these cases Venus will appear in front of the Sun. So we see a pattern of transits separated by 8 years, then 105.5 years, then 8 years, then 121.5 years, then 8 years...
@teamoliver Oh, and make sure your friend knows NEVER to look at the Sun through a telescope! :) There are filters available - a good telescope shop will be able to advise...
@teamoliver Yep you'd need a telescope to project the transit. There are also lots of observatories and amateur astronomers around the world webcasting the event if you don't have a telescope or can't see the transit from your location. This site has some great info: http://www.astronomerswithoutborders.org/projects/transit-of-venus.html
Get well soon.
Here's another video that probably explains it a little better than I do: http://www.youtube.com/watch?v=llbsMAuyI1Y