Observing on the Gulf Islands

In July, I visited one of the Gulf Islands in British Columbia, where my parents have a sea-side cottage. I brought my airline-portable 8" F/4 scope. The usual curiosity from airport security about the eight pound wooden box in my backpack, but no problems (I just need to allot an extra five minutes).

From my parents' front porch, I looked at and showed them M13, M27, M31/32, M51, M57, NGC 457, the Double Cluster and Albireo. The views were excellent. M27 had a very nice brighter squarish middle, with wings sticking out. I think that's tied for my nicest view of M27 (I've had a good view of it through my 13", too). When looking at M31, I couldn't see M110, perhaps because the M31 area was (a) low in the sky, and (b) that was the direction of Vancouver. NGC 457 (Owl/E.T./Airplane) always pleases people. We also saw a meteor and several satellites.

Once my parents went in, I went after the North American Nebula (NGC 7000). I have never had much luck with it. I saw it in my 68mm refractor with an O-III filter in a past year from the same location, but it was a very faint fuzzy with no structure. This time, still with an O-III filter, it was better due to better aperture: the edges were defined, and I could pan around it with the approximately two degree view of the Rini 30mm in the scope. (I should consider putting in a 2" focuser and using an even wider eyepiece in it.) I kind of got an impression of a shape reminiscent of North America, too.

I had heard that one can see the North American Nebula naked-eye with a filter if the sky is dark, and so I stared at the sky through the O-III filter. And I think I did in fact see it. I think I could also see M13 naked-eye with averted vision (no filter of course). It was almost directly overhead, so that helped no doubt.

The next time we went to a peak in the middle of the island, where I did an unofficial star party. We had almost thirty people show up, unofficially invited by email. We started with Saturn at around 10:15 pm. The rings were sharply defined, though I was using a low magnification due to the scope being fast and there being wind. (I also discarded the light shield due to wind.) I thought that it would be dark by 10:15 pm, but I didn't reckon with northern summer. It was closer to 11 pm before it was nice and dark. However, the party went very well. I showed the same objects as I had shown my parents, plus the Lagoon and Swan nebulae.

I always like it when deep sky objects are naked-eye visible. Overall, on the island, I naked-eye bagged North American (if O-III is allowed for naked-eye; but a filter only blocks light!), M8, M13, M31 and the Double Cluster. Only North American and M13 were particularly special to see naked-eye. M8 is naked-eye from my home, and M31 and Double Cluster are naked-eye from my regular observing location. I think sometimes I can see M31 naked-eye from home, too, but it's hard with the streetlights to the north.

Various things

It's been cloudy and rainy for a couple of days.

I'll be building a 70mm F/4.3 refractor with my five-year-old son.  Lens and diagonal have arrived ($33, from Sheldon Faworski).  We have a mailing tube of just about the right size.  I ordered some screws and nuts from Amazon to attach the lens to the tube.  I am working on a simplified PTFE-on-PTFE Crayford variant for the focuser, made out of one piece of wood, plus some hardware.  I'll post details once it's done.

I've spent some of the weekend playing with using a Wii remote with an IR pen.  This might be nice for operating Stellarium at public star parties.

Public star party idea

Something I've found to work well at public star parties is to have a durable telescope, or mounted binoculars, which the kids can themselves point.  Both of my tube dobs are durable and beat up, so I am happy to have the kids play with them.  Kids very quickly get the hang of pointing them with the red dot pointers I have on them.

Live Oak School Star Party -- perfect skies

The Live Oak School Star Party at the Waco Wetlands is all set for tonight, but do note that it is at the Waco Wetlands, not Reynolds Creek Park (see previous post for Wetlands directions).  Weather is perfect--no clouds within hundreds of miles of central Texas according to the weather map.

Live Oak School Star Party - same time, new place

Due to a mechanical problem at Reynolds Creek Park, we've had to move the Live Oak School Star Party to the Waco Wetlands.  Same time: Friday at 7:30 pm (come earlier if you're bringing a telescope).  This will be a bit of a longer drive, but the skies will be darker so we have a better chance at seeing Comet Hartley.  (And the facilities are nicer, too.)

Location: Waco Wetlands
Time: 7:30 pm on Friday, October 8, 2010
Directions: From Interstate 35 take the Exit 330 and proceed west (toward Meridian) on Hwy. 6/Loop 340. Continue for approximately ten miles to the intersection of Hwy 6 & FM 185. Turn right onto FM 185 and continue 0.6 miles then turn left on Eichelberger Crossing Road. The Lake Waco Wetlands Research and Education Center will be 1.6 miles on your right at 1752 Eichelberger Crossing Road.
Map: http://www.lakewacowetlands.com/map.html

Altitude brake

My Dobsonians move very smoothly.  The problem with that is that if I am showing things to the public, it is easy for people to push the scope away from the object, especially in altitude.  Before the last public star party, I made a little altitude brake, based on ideas on Cloudy Nights.  I used the router to cut a plywood disc the size of the altitude bearings (7" diameter) on my 13" scope.  (Actually, one could just cut a triangular piece with a hand saw.)  A plywood strip (with a plywood pad on the other end) is glued to it as a handle.  I attached three grippy rubber pads (one could put silicone sealant pads, too) near the circumference.  A bolt keeps the handle immobile, and a big 1/4"-20 carriage bolt runs from the inside of the mirror box, through the altitude bearing, through the disc, and then there is a fender washer and a knob to adjust tension.  The handle is bolted to the rocker box.  At low tension, movement is slowed down, but still smooth, despite the grippy pads.  At full tension, movement is stopped.  The original design I was following used a spring, but that doesn't seem to do anything.

I also made a smaller 2.5" version with Velcro hook pads just to slow down, but not stop, movement.  I didn't try it in the field, though.

Waco Star Party announcement

Here's something my local club is doing:

WACO STAR PARTY

June 5th, 2010
8:40pm to 10:30pm

The Central Texas Astronomical Society (CTAS) will have our Waco Star Party for members and the public on Saturday June 5th starting at 8:40pm, regardless of weather. We will meet as usual at the Waco Wetlands. Bring your telescope (if you just got a telescope and want help with it, this is a great place for that) or just enjoy those of the members as we explore the night sky of June.

We will begin with an indoor program on the life-cycle of stars, even if it's cloudy.

Then, weather-permitting, we hope to see objects both inside our Solar System, elsewhere in and around our Milky Way Galaxy, and outside our galaxy. In our Solar System, we will look at Mars and Saturn. Elsewhere in our galaxy, we would like to look at the Beehive open cluster of stars (M44) which can be seen with the naked eye as a faint glow, the Hercules globular cluster (M13) which is a ball of older stars that orbits our galaxy, and a nebula that is the remains of a burnt-out star (M97). Outside our galaxy, we will look at the Leo Triplet of galaxies, a trio of three galaxies that can be seen in one telescope field of view, and the Whirlpool Galaxy (M51)--a cannibal that is eating up a neighboring galaxy which can also be seen.

Experience it yourself and work with other local amateur astronomers to explore all that the night sky has to offer. This event is free to the public and is sponsored by CTAS.

Directions to observing site:
Lake Waco Wetlands at 1752 Eichelberger Crossing Road.

Directions: From Interstate 35 take the Exit 330 and proceed west (toward Meridian) on Hwy. 6/Loop 340. Continue for approximately ten miles to the intersection of Hwy 6 & FM 185. Turn right onto FM 185 and continue 0.6 miles then turn left on Eichelberger Crossing Road. The Lake Waco Wetlands Research and Education Center will be 1.6 miles on your right at 1752 Eichelberger Crossing Road.