April 04, 2013 #138 - First Look at the Southern Cross

On the 18th of March I had one of the most memorable observing sessions in my many years of  sky watching. We were set up just three miles north of the Mexican border on a hill top at Seminole St. Pk., TX.

Before sunset I set up my 20X80 D3 binoculars on a tripod an waited for the sun to drop below the horizon. I was able to see a mountain 46 miles into Mexico.

 The sunsets here in the Chihuahuan Desert have been spectacular. After sunset I picked up Comet Pann-Starrs and stayed with it till it faded just above the western horizon.

I then spent some time watching Jupiter and it's moons, Luna, and the Orion Nebula. The sky was fairly bright with moon glow so I went to bed to catch a few hours of sleep.

At about 2 am I returned to the binoculars just as the moon dropped below the horizon. The first target was Omega Centauri. It's hard to believe it's been over a month since I saw it for the first time. Then I hopped around comparing it to several other globular clusters (Marked on the chart). M13 was about 1/3 the size and all the others observed were less than it. Nothing compares to the "Big Dog" NGC 5139. It takes your breath away in  large binoculars and I spent at least 45 minutes admiring.

As the night became darker I went after my primary target the Southern Cross. I was able to pick out at least the top three stars above the mountains on the Mexican Horizon! It has been a life long dream of this Indiana boy to one day see this constellation! That dream finally came true. For the future the Magellanic Clouds and the entire Southern Cross.

For another hour or so I continued looking at these two showcase objects with a little eyeball scanning of the whole sky. Picked up several meteors and satellites and took a gander  at Saturn.

What a night, it was hard to go back to bed!

Clear Sky - Rich


April 03, 2013 #137 - McDonald Observatory, Ft. Davis, TX

For this post I'm including a few pictures from a tour of the facilities at McDonald Observatory. The view on the mountains is very impressive and well worth the time, about three hours. The tour starts out at the main visitors center. They present a history, an overview of the current research, a tutorial of spectroscopy, and real time observation of the sun with over all and close ups of current visible features.

Following this you are taken by van to the summit of Mt. Locke to examine the 107 inch telescope. You are able to closely examine the instrument where all phase of the observatory operation are explained and the scope and dome are operated to give you a first hand experience of instrument and dome procedures during a nights observation. I thought it interesting that the 30" core bored from the center of the mirror was retained to construct other telescopes. The foot and a half thick slab of glass was sliced into two pieces half as thick and optically worked to finished mirrors. One of these is on Mt. Locke and the other is at Kitt Peak Observatory.

The van then transports you to the 9.2 meter  H.E.T. scope on Mt Fowlkes to the north west. This scope is the fifth largest multi-segmented mirror in the world and the largest in the northern hemisphere. Each segment is monitored for proper orientation and computer aligned on a continuous basis. The entire scope is moved floating on a multiple cushions of air. The light is gathered and a corrector lens, again computer controlled on a track, insures precise focus to where the light is piped through optical cables to a spectrograph. This data is digitally transmitted to the researcher without that researcher having to be on the mountain. The scope is controlled and data collected by operating staff.

At the visitors center they also conduct Star Parties, weather permitting, on Tuesday, Friday, and Saturdays. Visitors can observe objects of opportunity through telescopes provided by the staff at a site near the visitors Center. The McDonald Observatory claims the darkest sky in the lower 48 states and plentiful nights of clear skies.

Mt. Locke

Mt. Fowlkes
View East from summit of Mt Locke
Close up of the 107" telescope dome
107" Rear View
Side view and Spectrograph
Movable Platform for 107" access
Dome just below 107" housing 30" built from center bore of mirror
Peak to peak view of H.E.T. Scope
Close up of H.E.T. Dome (B&W for better contrast view)
Edge of H.E.T. mirror showing sub-structure
Close up of individual mirror segment and support/control structure
Two floating air pads for rotation of telescope structure

 Clear Sky - Rich