Saturday, June 21, 2014

Happy Summer Solstice

Every summer solstice, the sun sets behind a nearby mountain topped with communication towers, as seen from my backyard. And every year, I forget to get a picture. This time, I remembered. Below are two photos of the sun dipping behind the towers. Both were taken with a 3" telescope at F6.3 using a white light solar filter. 



jg

Saturday, June 14, 2014

When looking up, don't forget to look down

A keen-eyed observer at the May 31 Explore the Stars noticed a glow on the sidewalk that turned out to be a caterpillar with a bio-luminescent belly. I tried to take photos, but getting a good focus in the dark was difficult. Still, I got close.

This close up captures the color of it's glow. I think this was a 5-10 second exposure.



Curious observers soon arrived and examined the sight with their red flashlights, which lit up the scene. 

I quickly realized that some context was essential to the photograph. The shadow of my tripod can be seen next to the glow.

A friend tells me that most likely it's parasites in the caterpillar that are creating the glow -- another subject to look up sometime.

jg

Comet PANSTARRS 2012k1

I'm hopeful of seeing comet PANSTARRS 2012k1 this month. On May 31, I took 28 mm focal length exposures of the region between Ursa Major and Leo and was able to capture the greenish comet

Location of PANSTARRS 2012k1 
on 31 May 2014 relative to Ursa Major.


In this photo, PANSTARRS is in the smaller circle:

My experience suggests that if I can capture a comet in a wide-field photo, I can see it in a medium sized telescopes and possibly in binoculars. However, dark observing conditions will be necessary.

Here is a close-up of the larger circle. the object in the middle has a green hue, common with comets:



Using the Heavens Above website, I created a map showing where to expect the comet on the weekends of June 21 and June 28: 



jg

UPDATE: I labeled the magnitudes of stars for estimating brightness. PANSTARRS is dimmer but more diffuse than a nearby 9th magnitude star.


Wednesday, June 4, 2014

Milky Way Mosaic

I believe this to be my first mosaic of the Milky Way:


I was on Palomar Mountain the night of May 31th, when a marine layer covered the surrounding area, leaving the sky unfettered by light pollution. My 28 mm focal length lens creates some distortion at the edges, and it's lowest f stop (2.8) introduces some brightness difference between the center and edge. I spliced two images and corrected the brightness and distortion in Photoshop. Perhaps "corrected" is the wrong word. I minimized the most obvious mismatches between the images.

This time of year is a good time to watch the Milky Way. It rises in the east, and in Southern California, many of our favorite viewing locations have desert to the east, thus reducing the impact from light pollution.

jg

Sunday, June 1, 2014

More great prominences

I photographed the sun through a hydrogen-alpha telescope yesterday, May 31, 2014. I used afocal photography (aiming a camera though an eyepiece). One out of 50 is good enough to sharpen in Photoshop so that the appearance here is almost as good as seen through the eyepiece.



jg