RA 20h 40m to 21h 00m, Dec -09 to -15

Last night I observed and sketched two double stars as well as M72, M73, and an un-named (as far as I know) small asterism similar to M73.

The session actually began with a sighting of the International Space Station gliding across the sky. The ISS appeared to be somewhat brighter than Jupiter -- a rather brilliant, white, moving light in the sky. Of course, as the ISS entered the earth's shadow it rapidly dimmed.

The seeing was 'good' -- a '6' on the modified Pickering Scale. I used 477x for the seeing check.

My NELM was 6.5.

Observations and sketches were all made at 135x, though other magnifications were used at times.

RA 20h 20m to 20h 40m, Dec -09 to -15

The mushroom cloud shown above was visible in the west this afternoon, but fortunately the smoke drifted south of me and the fire may have been successfully supressed by nightfall. The photo is an enlarged (and somewhat enhanced) portion of the original telephoto. The fire was not as close it may appear above. My sky appeared to be 'crystal clear' by the time I had begun my observing session.

In this region of sky (see title) I observed, split, and sketched seven double stars in the course of a little over an hour with the 13cm refractor. One was particularly nice, showing some color at low power. Another was a particularly close 'split'.

Seeing was much better on this evening (Tuesday evening, September 30th locally or October 1st UT) than it was on the previous evening. I rated it as being "Excellent" -- an "8" on the modified (for a 5-inch scope) Pickering Scale.

RA 20h 00m to 20h 20m, Dec -09 to -15

Four double stars were observed, split, and sketched in this region of sky last night. Seeing was 'good' (a '6' on the modified Pickering Scale). Temperature was +52 degrees F (+11 C). The 13cm refractor was used on an equatorial mount with clock-drive engaged.

My long-term goal: to cover the entire sky visible from my location - recording all visible objects of interest using my 13cm refractor. This isn't a new goal. Instead it's a revision of an earlier goal with a bit of modification. Time will tell if this 'new' program can stay alive.

Polar Doubles Revisited

Last night I re-observed the double stars listed in my previous blog entry. The seeing was a bit better this time around. Sketches, with north carefully noted, were made of all five double stars. A magnification of 135x was used for all of the double star sketches.

Prior to the double star observations I trained the scope on Jupiter -- as an object to focus on prior to adjusting the scope in its cradle. Balance is more sensitive for my home-made alt-az mount than it is for my equatorial.

As the bright twilight gradually faded, more stars popped out in the vicinity of Jupiter. A sketch was made at 43x of Jupiter, its moons, and some of the background stars. The seeing varied from poor to extremely poor at this point in time, but it had improved noticeably by the time I trained the 13cm refractor on the double stars.

My work schedule prevents me from making a more detailed post or refining and uploading sketches at this point in time.

Starting at the North Pole

Date: 27 September 2008
Time: 3:15 - 5:30 UT
Telescope: 13cm refractor
Mount: home-made alt-az
Diagonal: 1.25-inch 90-degree erect-image prism
Magnifications: 43x, 80x, 111x, 302x
NELM: 6.5
Seeing: very poor ('3' on Pickering Scale) - at session end
Temperature: +50 F (+10 C) - at session end

Using the Millennium Atlas as my guide I sought out objects within about 3-degrees of the north celestial pole.

The star diagonal used is not of the highest quality, but for an erect-image diagonal it is of reasonable quality. This diagonal was used in order to more easily match the eyepiece view with the detailed atlas charts.

My old alt-az mount was used under the assumption that it would make it easier to navigate around the celestial pole -- easier than using an equatorial mount. At a later date I'll determine whether or not that assumption reflects accurately on reality.

The seeing and temperature were not recorded until the end of the session. A high magnification (302x in this instance) was necessary in order to obtain an accurate value for the astronomical seeing. For all other observations the maximum magnification used was 111x.

Five double stars were 'split' on this evening. Their rough coordinates are given below:

RA 02h 35m, Dec +89.3 degrees (Polaris, Alpha Ursae Majoris) very bright primary with much fainter secondary

RA 08h 20m, Dec +87.25 easily split at all magnifications, not particularly bright

RA 12h 00m, Dec +87.0 a nice double, best at about 80x

RA 12h 30m, Dec +88.7 a close, unequal double, cleanly split at 80x

RA 18h 40m, Dec +88.3 an unequal, easily split double (140 lightyears distant)

Other objects and double stars were looked for, but were either not positively seen or not positively split.

Jupiter & Lambda Ophiuchi

Date: 03 September 2007 U.T.
Time: 2:03 - 2:15 U.T. (Jupiter)
Telescope: 130mm refractor
Magnification: 138x (Jupiter)
Filter: Moon-SkyGlow (Jupiter)
Seeing: Poor to Fair
NELM: Twilight (Jupiter)
Temperature: +83 F (+28 C) (Jupiter)

The above rough (at the telescope) sketch of Jupiter has North up and Preceding to the left.

Due to poor seeing conditions small-scale, moving "ripples" were constantly visible around the limb of the planet. The "star" to the upper right of the planet is Io, one of Jupiter's moons. A little later in the evening Io was seen in transit across the planet's disk. The following limb of the planet was slightly darker than the preceding limb due to the sun angle (a slight phase effect). At times more detail was visible; but under the circumstances (poor seeing and a relatively quick observation and sketch) some of the details shown may not be particularly accurate.

The planet's North Equatorial Belt (the darkest belt on the planet) appeared brownish-red in color. Other features had colors that were too subtle to differentiate from shades of gray.



After completing the Jupiter observation I observed and sketched Lamda Ophiuchi A&B, a close double star. The above sketch (greatly enlarged from the telescopic view) shows this double with North up and West to the left. A #82A Light Blue filter sharpened the view a bit under the relatively poor seeing conditions. The "A" star appeared to have a yellow or yellow-orange color while the "B" component appeared bluish. A narrow gap was visible between the two stars during intervals of somewhat improved seeing conditions. A weak, broken, diffraction ring was also visible at times around the two stars. A magnification of 218x was used for this observation.

Sharing the View

Date: 3 June 2007 U.T.
Time: 3:00 - 5:00 U.T.
Telescope: 13cm refractor
Magnifications: 35x, 90x, 170x, 240x
Filters: #56 and #58 Green (for Venus only)
Seeing: Good
Transparency: Bright and darkening twilight

After many cloudy or otherwise missed nights everything fell into place for a good evening. The telescope was set up on on an equatorial mount with an electric RA drive. The motorized tracking simplified sharing the view with two guests.

Venus was our first target, and for a long while our only target. The seeing was very steady with the refractor -- one of the benefits to using a relatively small telescope. The planet's sharply defined quarter (or 'half-moon') phase was easily visible to everyone present.

The green filters helped cut down the brightness of the brilliant, white planet to a more tolerable level. We took turns studying the planet at 90x. Through the use of questions and answers, it looked like the guests may have been able to perceive some of the subtle markings in the Venusian atmosphere.

Eventually the sky darkened enough for the younger guest to spot Saturn in the twilight sky. We shared views at 35x and gradually worked our way up to 240x. Titan was immediately noticed near the ringed planet. After the sky had darkened a bit more we saw three more of Saturn's moons. The two moons between Titan and the planet, one above the other, were later identified as Tethys (to the north) and Rhea (south of Tethys). Just off the north-following limb of the planet was Dione.

At the higher magnifications the ring was visible in front of the planet. The guests also noticed Saturn's South Equatorial Belt (SEB). Cassini's Division presented a challenge for the guests, but they eventually succeeded in seeing this division between Saturn's A and B rings -- at least on one side of the ring system. The shadow of the planet on the ring system proved to be a bit more of a challenge for the guests.

After Saturn we took a look at the globular cluster, M13 in Hercules. Next was the Ring Nebula (M57) in Lyra. The final object was Albireo (Beta Cygni) -- one of the northern hemisphere's "showpiece" double stars.

Twilight had still not quite ended by the sessions end. Nevertheless, part of the summer Milky Way was seen. We also saw at least one meteor, an airplane and at least one satellite.