Category: Solar System

Joan Genebriera of AstroPalma kindly pointed out that there is a large white spot on my last image of Saturn. This is the giant storm that’s been raging since the end of last year so I’m quite pleased to have captured it. There’s a Hubble picture of the storm here:
http://planetary.org/image/saturn_JBNY02SQQ_hubble_20110312.png

With a bright full moon in the sky Dan and I decided to spend the night trying to better understand the society’s 20″ reflector. Getting the best out of it is definitely an art rather than science and the longer you spend with it the better you get to know it’s strange quirks and foibles.

After some time with the Orion nebula I put the webcam on with Televue x2.5 and took some 10fps videos of Saturn. The final one looked the best on the laptop so I stacked 400 of the best frames in Registax and applied a lot of sharpening.

The rings have noticibly opened since last year and as it climbs higher in the sky it should present a nice target later in the year.

A rare clear interval on Tuesday evening at the observatory and I put my modified webcam on the 20? with a narrowband infra-red filter. The seeing wasn’t up to much but I got some pictures both with and without a x2 barlow.

The southern cloud band that so dramatically disappeared last year is back although in this image it does appear to have a gap in it where it’s still obscured by higher level clouds.

Having had time to sort through the pictures, I like this one rather better. I really underestimated just how bright the sun would be at this low altitude, but this one has less distracting flare. For the next time a solar filter will be a must.

So, this is ISO 100, 1/200 second at f/32. For later pictures I used 1/4000. The bright sun really messed up the auto white balance and gave the entire picture an orange glow. I’ve rebalanced this image towards the blue so the colours are closer to what I actually saw.

Just as I thought I wasn’t going to see it the cloud dispersed sufficiently and there it was. First picture is here, more to follow.

In the last picture, the crescent of the moon is almost invisible against the dawn light.

Tuesday morning was bright and clear (and minus 9C) when I left the house at 06:30 to walk to the top of the lane. As I setup the camera and tripod, the Earth’s shadow was just starting to take the first bite out of the lunar disk. Sticking mainly with the Canon 75-300 zoom I took pictures until the moon faded into the dawn sky as it reached totality. At 07:30 I took this wider field image.

Camera: Canon 350D
Lens: Canon 75-300 zoom @ 125mm f/4.5
ISO: 400, 1/3 sec

Once every year the Earth overtakes Jupiter on the inside track and as Jupiter is opposite to the Sun in the sky this is known as Opposition. As the planetary orbits are not circular, the inter-planetary distance varies each year and this year Jupiter is the closest it’s been since 1963. Additionally, for Northern hemisphere observers it’s also higher in the sky than it’s been for many years and this results in a clearer view as there’s less of our atmosphere in the way. To add additional interest this year, the southern equatorial cloud belt has disappeared although it’s just beginning to make a comeback.

Also in this picture, the moon Ganymede has just re-appeared from behind Jupiter.

This image was taken on Tuesday evening with the club 9.25? Celestron SCT with a 2.5x PowerMate  and modified Phillips SPC900 camera. It’s a stack of about 1000 frames processed in Registax.

Friday evening at the Observatory was spent showing some visitors around. As it was clear we were able to look at Venus, Mars, Jupiter and Uranus as well as the Moon through the 20?. Although the planets were all very low and suffering from massive amounts of atmospheric dispersion they went away happy.

After that, it was down to the main business of the night, measuring periodic error on the 20? drives. This shows that we have some more work to do to stop drift on the altitude drive and also that we have about 7 arc seconds  peak to peak periodic error on the azimuth axis.

By this time, Jupiter was high in the sky so we finished up putting my modified Philips webcam on with a 2.5x PowerMate for some video images. Jupiter is more favourably positioned for Northern hemisphere observers than it has been for many years and it was nice to see it at a decent altitude with lots of detail visible in the eyepiece.