Hodgson Observatory

Very low sunspot activity continued through January this year. No sunspots were seen on Jan. 1, 4, 6, 21, 22, 28, or 31. The only positive observation was on Jan. 10 when a fine but small sunspot group with four principal spots was seen, the first sunspot group seen at Hodgson Observatory since 2008 Jan. 31.

A majority of observations at our Main and Wide-Sky Observatories are informal and educational, and not formally recorded or published. These include most New Moon gatherings, and the South Dakota Star Party. The more formal sessions are carefully logged and documented with field notes as Scientific Observations.In 2009 there were 53 scientific observations distributed as follows:Main Observatory, 11 (20.8% of total)Wide-Sky Observatory, 38 (71.7%, of which 30 were solar, 1 lunar daytime, 7 nocturnal)Elsewhere on Hodgson Observatory grounds, 4 (7.5%, binocular / naked eye events)The most exciting observation of the year was the unexpected sight of “the umbral ring shadow, jet black, narrow, but striking, on the ball of the planet” [Saturn] as the 2008 May 6 log records.Let’s hope 2009 provides even more exciting observations!

Detailed study of sunspots and related phenomena require very sophisticated and expensive equipment, such as that found at Kitt Peak and other Earth-based observatories, or monitors found in spacecraft. Researchers wishing definitive information on 2008 sunspot activity do well to consult the websites of NASA and other major solar observatories. That said, there is still a satisfaction in making your own solar observations, and then at year’s end looking back at what you have recorded. The imperfect but personal investigation made at Hodgson Observatory in 2008 may be of local interest. In 2008, solar observations were made at the Hodgson Observatory Wide-Sky facility on 30 different days with the 203mm aperture f/4.9 Newtonian reflector, using a full aperture solar filter and magnifications of 25x to 115x. The most active months of solar observation in 2008 were January, February, October, November, and December. We were limited by many cloudy days, high winds, extreme temperatures, involvement in other projects including building the new Astro Lodge, and travel away from home.

As viewed at Hodgson Observatory throughout 2008 sunspot activity was at a protracted very low level. This is in line with other reports. One would have to go back to 1954 or earlier to find a similar low level. Indeed going back to mid-November 2007 when our Wide-Sky facility began to focus on sunspot activity, minimal spot activity has been the rule. In late 2007, of six observations only one was positive, a fine spot group on December 12. In 2008, spots were only seen on January 31 (a fine group with 2 major and 3 minor spots), and on October 3 (one lone small spot). Of course other spots were missed when we were not looking, some of them doubtless short-lived, but the broad reality is clear. Where is the new sunspot cycle? Are we entering a protracted minimum like the Maunder Minimum of 1645-1715?  One wonders!  It is much too soon to be sure, but we are in fact overdue for a long minimum, a break in the sunspot cycle.

The Maunder Minimum had some major negative climate impact on Earth. Are we minor witnesses to some major history?  We will keep watching in 2009. (Already in 2009,  January 1 and 4 have provided us with negative observations.)

Because of extensive travels from “Harvard Yard in Massachusetts to Harvard Glacier in Alaska” by the Hodgsons in May and June, the preoccupation of SEAC members in the construction of the Astro-Lodge meeting place on Hodgson Observatory grounds (see pictures posted elsewhere on this website), and frequent adverse weather, observations were relatively few this summer.

MAIN OBSERVATORY observations with the 645mm reflector and 120mm refractor included Saturn before and after sunset and deep-sky objects M104 (Sombrero Galaxy), NGC 4361, a planetary nebula in Corvus, and NGC 4038/39 (the Ringtail Galaxies) in Corvus on May 4.

[On May 5 (CDT) the striking observation of the umbral ring shadow on Saturn was made. This is separately described above.]

On May 7 Saturn was re-observed, along with M65, M66, and NGC 3628, all galaxies in Leo; NGC 4147 in Virgo, an often neglected globular cluster, was partly resolved at 201x; M53, a bright globular cluster in Coma was moderately resolved; M64 (the Black-Eye Galaxy) in Coma was also observed.

On August 20 and 23 Jupiter and its Galilean satellites were observed at length. On August 30, during the South Dakota Star Party, both Jupiter and Neptune were observed, but rising winds cut observations short. (All dates are CDT time.)

The WIDE SKY OBSERVATORY with its 203mm reflector and 80mm refractor were used for brief observations during the summer. The reflector with its full aperture solar filter was used to examine the Sun’s disk many times. No sunspots were seen throughout the summer, raising the prospect of a possible long minimum in coming years.

Probably the most exciting observation at Hodgson Observatory in the summer of 2008 was the unexpected sight of the jet black ring shadow of Saturn’s C Ring falling on the globe of the planet! Dick Hodgson, a long-time Saturn observer, saw it for the first time in his life when observing alone on May 5 (CDT).

The shadow made an extremely dark, narrow line across the planet’s atmosphere. Due to the narrowing of Saturn’s rings the ring shadow was not then “penumbral” letting some light through, but had intensified to umbral, so that region as seen from Saturn’s upper atmosphere would be equivalent to our total solar eclipse. What a striking black line it was!

Sky & Telescopes’s Alan MacRobert, commenting on the observation said, “This is indeed just about the best time this year for seeing the shadow of Saturn’s rings as a thin black lkne on the globe…. In most scopes, when the shadow is here it just gets blended with the dusky shading of the C ring. Your 25-inch is clearly a superior scope to be able to resolve so sharply…!” The observation was also confirmed a few nights later by SEAC member Rein Vander Hill of Orange City, Iowa, with his 20-inch Obsession telescope.

Adverse weather this month again hindered our observing efforts with a mid-month snowstorm and frequent clouds and high winds. The New Moon Saturday gathering met for a pot luck supper and we had a number of good discussions about equipment and observing. Unfortunately, the winds and clouds again prevented our observing.

 Solar disk observations made with the 203mm (8-inch) reflector on April 7 and 26 showed no sunspots visible. A few spots have been reported, but are gone when we can look. April was both a cloudy and windy month!

There were only two extended night-time observing sessions in the month. On April 13/14, JJ (John Johnson) came down from Sioux Falls with Joe Brown bringing JJ’s 508mm (20-inch) Obsession telescope. JJ observed a gibbous Moon in the sky along with Mars, Saturn, and the brighter globular clusters. Two impressive planetary nebulae that he saw, in spite of moonlight, were NGC 3203, “the Ghost of Jupiter” in Hydra and NGC 6542, “the Cat’s Eye” in Draco, whose central star dazzled like a diamond. Dick also viewed brighter globular clusters: M3 in Cannes Venatici, M53 in Coma Berenices, and M13 in Hercules.

On April 19 (CDT date) Dick, observing alone, spent over two hours viewing the Saturn system in detail, seeing classic satellites Enceladus out through Titan, all in spite of a very bright full Moon. It was good to have temperatures above freezing!

Observing efforts were hindered by continued adverse weather, including snowstorms, extensive cloud and high winds. The New Moon Saturday gathering, like those of the previous three months, was not held in March.

 Solar disc observations made with the 203mm (8-inch) reflector on March 12 and 13 showed no sunspots visible. There were a few other sunny days in March, but they were days when it was either too windy to observe or had priority items scheduled.

There was only one extended nitht-time observing session in March. That was on the evening of March 10 (CDT date). At low power conditions were good, but mediocre  at high power that night. John Johnson (“JJ”) used his 120mm Newtonian with GoTo at ~50x to observe Saturn and 27 Messier objects and a few NGC objects. Dick Hodgson used his 635mm Obsession in the Main Observatory at both 84.6x and 201x to view Mars and its Syrtis Major, followed by Saturn. Its classic satellites from Mimas out through Titan were all identified. A few Messier objects were also examined with the big scope.

February was a limited month for observation this year. Many nights were clouded out or too bitterly cold to be outside. Solar disk observations were made thrice with the 203mm reflector using 77x (Feb. 8, 22, & 27). No sunspots were seen. The total lunar ecllipse of Feb. 20 (CST), previously reported, was a delight in spite of the bitter cold “Leap Night” (also previously noted) was the best observing of the month!

If February 29 is Leap Day, its evening must be “Leap Night.” It was an outstanding dark night! John Johnson set up his fine 120mm refractor on our Observatory grounds, observing Mars (Syrtis Major and a polar cap) and Saturn plus five of its satellites (Enceladus, Tethys, Dione, Rhea and Titan). He also viewed briefly 23 Messier objects and 4 NGC objects (all listed in the Observatory Log). He was greatly aided by his Atlas GoTo mount in covering so many objects! The view of M78 in Orion was the best he has ever seen he reports. Bravo, JJ!

An early evening meeting delayed my own observing, but when I did about 10 o’clock (CST) with my 635mm Obsession reflector, Saturn’s  five satellites mentioned above were all seen again pllus Mimas, Saturnn’s innermost classical satellite. It was quite faint, just E of the end of the A Ring at the time. I had not seen Mimas since the 1970′s  – it sure helps to have Saturn’s rings rapidly closing to see close-in objects! Observers should use 2008 to view Saturn’s inner satellites. Don’t delay!

The February total lunar eclipse was observed from the grounds of Hodgson Observatory by Nancy and Dick Hodgson. Fortunately early evening clouds cleared away prior to totality. Unfortunately the air temperature was minus 6 degrees F.with a light breeze from the east!  Fighting the cold Nancy managed to secure several digital photographs. Dick scrutinized the eclipsed Moon with an 8x32mm monocular, and gave mid-eclipse value of ~3.5 to 3.7 on the Danjon Scale.