Wednesday, 25 May 2016

Book of doodles coming soon

I just uploaded a book (102 pages) of cartoons/doodles related to eclipses and astronomy to a web site called CreateSpace where they print on demand. That is, if you give them a little money, they will print a copy and send it to you plus they will share a bit of that money with me. Saves printing a bunch and trying to sell them door to door. The Internet is really a wonderful place. Plus only really interested people will demand a copy, that's a couple hundred at best I figure. It was all in good fun at the urging of Fred Espenak and Michael Zeiler, two eclipse chasing experts that are frequent targets of my silly doodles.

Many of the doodles have appeared in various lectures by myself and other chasers. Some were requested and others just came to me as funny ideas. At the Solar Eclipse Conference in 2014 a lot of the doodles were used to introduce the various speakers and topics. Expert eclipse chasers appreciated the humorous look at their hobby or vocation.

When the book is ready for demanding I will post a link at the main web site as well as a note here in the blog. In the mean time, get ready to get to totality in August 2017!

Thursday, 12 May 2016

Transit of Mercury - 2016 - a rare and boring solar system event

Maybe boring is too strong a word. Or maybe I just undersold the event to local friends. No one showed up to take a look except the gardener (and that was the first time he'd ever looked through a telescope). Oh well, I got to hog the eyepiece the entire time! Using my 8" SkyQuest (from Orion) and a full aperture solar filter, I watched for a little over an hour.

Is a Transit of Mercury worth travel to see? Maybe for some, but not for me.

Holding my iPhone to the eyepiece I snapped a couple images. The first shows the full disk of the Sun. Mercury is the tiny dot at the 1:20 position (12:00 is up) about half way from the center to the edge. There are several sunspot groups visible too. This is the view through the 40mm eyepiece.

Amazed by the success of holding the phone/camera to the eyepiece I upped the magnification by putting a 10mm eyepiece in. Mercury is on the top and a sunspot group is visible towards the bottom. 

Below is the set up area. I am in the lower left of the image with my telescope. While it looks windy, it is not too bad. The prevailing winds have blown the palms to look like it is always windy.

Sunday, 1 May 2016

Is that Mercury?

The upcoming transit of Mercury (9th of May) falls at a great time. It can be seen, at least partially, across much of Asia, Europe, Africa, North & South America. Sorry Australia, you miss out on this one.

For details, see:

Like a partial solar eclipse, observing the transit requires looking at the Sun. Looking at the Sun is a dangerous  activity without the proper equipment. If you don't have a proven solar observing system in place, then seek out someone that does to see the transit.

So what makes up a proven solar observing system?
McMath-Pierce Solar Observatory

How about Solar (Eclipse) Glasses? - Not good enough. You will need magnification to see the Mercury transit.

Mercury is very small. Even at the closest point it is only 1/150th of the size of the Sun. That is too small to see. The human eye can resolve about 1-2 arc minutes at best (ref.). The Sun ends up being about half a degree (30 arc minutes, 1800 arc seconds) in size up in the sky. Mercury is a mere 12 arc seconds.

You will need a telescope.

Please remember, solar glasses are NOT TO BE USED WITH A TELESCOPE.

Solar filter on a telescope?
Might be good enough, with some magnification. You will need about 50x to see the dot clearly. Higher magnification reveals a small disk. And it can be easily mistaken for a sun spot.

My favorite method of observing a transit is to use a projection set up. Any telescope, carefully monitored, can be used to produce a clear image of the solar disk. Practice is always recommended and be careful. Having the telescope pointed at the Sun is potentially dangerous and should be done in short intervals to avoid heating the optics or tube too much. Use extreme caution.

Transit of Venus projection

The transit is a rare event. Only a dozen or so times per century can one see Mercury go across the Sun. If you have a proven solar observing system or know someone who does, try to catch on the 9th of May. In Jamaica it will be taking place shortly after sunrise. We normally have clear sky in the morning so I hope to get a few images. They will be posted to this blog of course!