Sunspots: 9 July 2009

Today's sunspot observation was made with the help of Buttercup, a 60mm achromat refractor. The above photo of Buttercup was taken shortly after I had completed today's sunspot sketch. The short cardboard tube visible on the front of the telescope is a home-made solar filter utilizing safe, Baader Solar Filter material. Permanent eye damage or blindness is likely to occur if proper safety procedures are not followed when observing the sun. The telescope's finder has black covers over both ends as a further safety measure.

Today's sketch, shown above, has north up and preceeding to the left. The image is mirror-reversed due to the use of a star diagonal. A magnification of 70x was utilized. The sketch shows just a small region within the telescope's field of view.

When sunspots are observed near the limb of the sun one should always look for faculae -- areas that appear brighter than the background solar surface. Faculae were noticed and sketched today, but those regions do not show up well in the scanned image.

July 7th Sunspot Group

The above sketch shows the sunspot group observed from 15:54 until 16:04 U.T. on 7 July 2009. A 60mm f/11 achromat refractor (Buttercup) was used at 70x for the observation and sketch. Use of a star diagonal resulted in a mirror-reversed view. North is up and preceeding is to the left. It's good to finally see some sunspot activity on our nearest star!

Moon Occults Venus

The above sketch shows Venus and Earth's moon after sunrise, but just before the moon passed in front of Earth's sister planet on Earthday morning. The sketch is a fairly close approximation of the view through 20x80 binoculars. East is toward the lower left. North is toward the upper left.

Later in the day I showed students our moon, Venus, and the sun using Buttercup (a 60mm refractor) at 28x. Some of the students managed to see the moon and Venus in the daytime with their unaided eyes! By this point in time Venus was a fair distance west of the moon.

Buttercup views Saturn: 16 March 2009

Saturn and Titan were sketched last night while observing with Buttercup, a 60mm refractor. The planet was tiny at 28x and still rather small at 70x -- the magnification used for the above observation. North is approximately up. Preceding (west) is to the left. A subtle, slightly darker band was just visible (or suspected) north of and running parallel to the ring plane. The point of light to the left of Saturn is Saturn's largest moon, Titan.

Sun & Venus 15-16 March 2009 U.T.

The above sketch shows Venus at 0:55 16 March 2009 U.T. as it appeared in "Buttercup", a 60mm refractor, at 70x. The observation was made around sunset under fair seeing conditions through thin clouds. The planet's apparent diameter was quite large. Even at 28x the planet seemed large! North is up. Preceding (west) is to the left. Though a complete disk appears in the sketch, only the bright, thin crescent was visible.

The sun appears in the above sketch with clouds sihlouetted against the bright solar disk. The observation was made through thin clouds at 28x with a full-aperture, objective solar filter at 23:10 on 15 March 2009 U.T. The densest clouds were even visible against the background sky. Unfortunately they don't show up in the scanned image of the sketch. No sunspots were noticed. Limb darkening and clouds were all that was noticed on (or in front of ) the sun's disk. The solar filter was home-made using Baader Solar Filter material. Never look at the sun without proper eye protection!

"Buttercup"

Shown above is the same old, banged-up 60mm refractor that appeared earlier in this blog. The telescope has been improved here and there. After adding some weight inside the rear of the OTA the scope balances better in its fork. The altitude trunnions have been attached more solidly than before. The tube assemblies have been painted yellow with black trim. The wood tripod legs have had their dark paint removed and replaced with a somewhat lighter stain and varnish.

In the tradition of my other telescopes, this one also has acquired a name. Today marks the birth and first-light of "Buttercup".

Venus was Buttercup's first target. Shown above is the rough, at-the-telescope sketch of Venus made at 1:00 on 04 March 2009 U.T. at 70x. Unfortunately the sky had clouded over by the time I went back outside in the hope of observing the moon.

Comet Lulin (C/2007 N1) 22 Feb. 2009

The above sketch shows the full-field view I had of Comet Lulin last night with 25x100 binoculars. Comet Lulin was easily visible to my unaided eyes from my dark-sky (Naked Eye Limiting Magnitude 6.5), rural location. North is up and east is to the left in the sketch. The field of view is approximately 2.3 degrees. From a dark sky any pair of binoculars will provide a pleasant view of Comet Lulin.

I've been observing this comet for a while now, but this is obviously my first blog entry on our latest celestial visitor. There's just so much to do these days . . .

Venus & Pythagoras

The above photo shows our visiting wild turkeys on the run. I like this photo for showing some of the resemblance between wild turkeys and their T-Rex and velociraptor relatives. Really though, I felt like showing something but didn't feel like putting in the work to polish up the evening's astronomical sketches.

Venus was easily found with the unaided eye shortly before sunset. I took out the 60mm refractor and made a more careful (than last time) sketch. This time I recorded some background colors to give a better idea of the visual impression of the planet as seen in the small, low-cost telescope. I might upload a sketch later . . .

Pythagoras is a large, 130km wide lunar crater. It was prominent (and greatly foreshortened) along the terminator of this evening's gibbous moon. Pythagoras's central peak was very obvious, standing out as a bright notch in the non-illuminated portion of the crater. The nearby 144km wide crater Babbage, with Babbage A within its border, aided in positively identifying Pythagoras.

I have only one 0.965 O.D. eyepiece -- the size that fits the 60mm refractor's diagonal. Therefore I'm currently restricted to using only one magnification (28x) with this telescope.

Venus - 02 February 2009

The above sketch of Venus depicts the general appearance of the planet on 02 February 2009 at 0:40 UT at about 30x with a 60mm f/11 achromat. West is to the lower left. North is to the upper left. Of course, at 30x the planet didn't look as large as it appears above, but the fat crescent was none the less sharply defined and easy to see.

Interestingly, a 60mm f/11 achromat is virtually free of false color at 30x. Venus as well as our own crescent moon were sharply defined with little false color (chromatic aberration). Galileo would have loved to use a telescope like this!

It was unnecessary to provide any specific cool-down time for the small refractor. The outside temperature was about 40 degrees (F) cooler than the inside temperature. Yet the image was sharp and crisp when I looked into the eyepiece. Smaller telescopes have some disadvantages, but they also have their advantages!

Meade Model 226 60mm Refractor

Shown above is a newly acquired, old, Meade model 226, 60mm alt-az refractor. I had to replace seven missing screws of one kind or another. When acquired, the scope was in its mount backwards. That situation was remedied prior to taking these photos. The prism diagonal had to be removed for a proper cleaning. Somewhat surprisingly, all optical surfaces were totally without visible scratches!

This fixer-upper scope will be used partially for educational purposes (how to make the most of the least, etc.) and partially for me to take notes and make sketches regarding what can be seen with such a telescope.

Note the stopped-down aperture of the finder: The purpose of a stopped-down aperture is to mask aberrations (distortions) that would otherwise be visible when looking through a telescope that has a poorly designed objective. Such finders can be useful under daytime and twilight conditions, but used under a dark sky for anything other than the brightest of targets they can become liabilities. I found it easier to see poorly illuminated terrestrial objects with the naked eye than with this finder! If your child's telescope has a finder like this I would suggest replacing it with something more useful such as one of the many 1x red-dot finders (or a 5x24 finder that is not stopped down) that are available now.

I'll keep the original finder on this scope for educational purposes and for those occasions when it remains of some use. An experienced observer would have little difficulty in sighting along the primary scope's tube to successfully point it as long as the telescope's magnification isn't too high, but a child might easily become frustrated without a more useful finder.

The telescope's objective is clean and scratch free, though when the scope was first acquired the objective was filthy!

At some future date, when weather and time permit, I hope to re-paint the telescope, re-finish the wood tripod legs and make some final tweaks to enhance the scope's usefullness.