Astronomy – Page 10 – A Darker View

My Telescope Sings to Me

OK, I did not expect this.

I have been observing from my driveway each evening this last week now that the Moon has left the evening sky. Pleasant sessions wandering through the stars and clusters of Scorpius, Sagittarius, and Ara.

The week has also featured gentle trade winds at the house, resulting in fickle breezes around the telescope which is mostly in the shelter of the house. I get some manini gusts that make it around the garage that really do not bother me but do keep the mosquitoes down.

These breeze have created an unexpected phenomena, they make my telescope sing to me.

It is a gentle and resonant low B note as the breeze plays past the front of the telescope. Much like blowing across the top of a beer bottle, the tube of the telescope resonates with the breeze. Apparently a Cave Astrola 8″ f/6 telescope is a tenor.

Sometimes quiet, sometimes quite notable, I listen to the telescope hum while I look up the next cluster to observe.

Now if you excuse me I need to chase the pigs out of the yard… Again.

Driveway Observing

Eyepiece Time

Given stay at home orders and a virus haunting our community I have gotten quite a bit of eyepiece time this year. Mostly quick driveway session in the evening, or sometimes the early dawn hours, a solo activity perfect for social distancing.

I usually use my roll-out scope ready in the corner of the garage, a classic 8″ Cave Astrola. Just roll it into the driveway, plug it in using the purpose located power receptacle on the corner of the lanai,. slide an eyepiece in… Ready to go in two minutes.

Last night was a perfect example… It was raining at sunset, but an hour later the skies were clear and dark. Better yet the rain had left clear, haze free air overhead with great transparency. I spent an hour hunting down dark nebulae in Aquila, dark clouds of galactic dust best visible with perfect skies.

The pages of the observing notebook fill quickly, a page or two each evening until the Moon comes back. I have so many object I have never viewed, so many easily visible from the driveway with a fairly small 8″ ‘scope.

Often I come across pleasant surprises, a pretty binary or a deep red carbon star, the region surrounding my target rich with stars and wisps of nebulae, so many wonders I have never seen despite years at the eyepiece.

Chasing a Comet in the Dawn

Comet C/2020 F3 NEOWISE

A Bright Comet in the Dawn

We have a bright comet in the dawn sky for a few days. Comet C/2020 F3 NEOWISE has brightened rapidly over the past few weeks, now about 1st magnitude it can just be seen against the glow of dawn.

I took along Hodepodge to serve as a tracking mount for the TV-76mm scope and a couple cameras to do some comet shooting. The Canon 6D would go with the small ‘scope, the EOS-M5 with a tripod for wide angle shots.

Driving up Waikoloa road I was troubled by a bank of clouds in the Waimea saddle, thus I elected to head for the Humuʻula saddle instead. I ended up in the lava fields along the Mauna Loa access road. The view was perfect, and I had just enough time to get the mount and camera setup as the comet rose.

The Veil in Hydrogen Alpha

To allow a wider field of view requires changing optics. In this case putting away the TV-76mm telescope and mounting a vintage Nikkor 180mm f/2.8 ED camera lens.

The Nikkor 180mm is a classic lens, once a favorite of professional film photographers for news and portrait work. Now the lens is out of date, not autofocus, or image stabilized, a bit of very good optics left behind by technology.

Of course, autofocus or image stabilization are useless for astrophotography. With a simple adapter the lens can be mounted to a modern system and used as a fully manual lens in an application where the excellent optical quality can still be appreciated.

The Hercules Cluster

The Hercules Cluster is one of the best known, and as you would expect, one of the most beautiful clusters to be seen in a small telescope. Also known as M13 this is a rich globular cluster with several hundred thousand stars it lies about 25,000 light years away in the constellation Hercules.

The cluster is always worth stopping by, whatever size telescope you are using. If I am using a larger ‘scope I might try to locate the small galaxy NGC6207 located about ½° to the northeast (upper left). If I am using an even larger ‘scope like my 18″ I can also try for the challenging IC4617 that lies halfway between NGC6207 and the cluster.

The image here is a luminance image only, taken through a filter that blocks IR and allows the remainder of the visible spectrum through to the detector. To get allow capture of the fainter stars while not overexposing the core a range of exposures from 10 seconds to five minutes were combined to create the image seen here…

Rho Ophiuchi Region in Monochrome

The Rho Ophiuchi region is a confused mass of gas and dust just above Antares and the head of Scorpio. This extensive nebula complex is far larger than the single frame shown here, extending far to the east into Sagittarius.

Rho Ophiuchi itself is the triple star seen here at the top center of the image, at the center of a bright reflection nebula. The double at lower center is Iota Scorpii and the star Al Niyat is on the right side. Also notable are the dark clouds of dust and gas that block the light of the stars and nebula behind creating black voids in the starfield.

This area is quite colorful, with both the blues of reflection nebulae and the reds of emission nebulae. I have gathered some color data but need more before assembling a proper color image of this region.

Leo Galaxies

Just killing some time while I wait for the Milky Way to rise and to shoot my primary targets for the night. Maybe some galaxies in Leo? There are a lot to choose from, but I am setup for wide field using the TV-76mm with only 389mm of focal length. Too wide to make individual galaxies interesting, maybe a galaxy group?

The group around M95/M96/M105 should be good, it fits in the field nicely. Just shoot for about an hour before moving on the the main targets of the night. With any luck those wisps of evening clouds hanging about will go away as well.

There are a number of nice groupings of galaxies in Leo… The Leo Trio (M65, M66, and NGC3628), and this group around M95 and M96, and a number of fainter galaxy pairs and clusters to chose from.