Log, Jul 20, 2001

I won't keep reminding you about the newly created Southern New England Stargazers email news group, but for those who missed the announcement this new group formed by several members of the FDO community can be found at:

http://snegazers.brainiac.com

While intended to support the southern New England astronomical community (Connecticut, Massachusetts and Rhode Island), it is open to everyone, everywhere interested in astronomy, if you don't mind our obvious geographical focus.

-Les Coleman

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76 people signed the log. There were many who didn't, as well (30 or more).

With no moon and the promise of dark skies throughout the night, a crowd of enthusiastic public and members gathered early at FDO tonight. By 7:30 both Steve B. and Doug S. had arrived (accompanied by two families of visitors) and Art G. and Joe H. were close on their heels. Les C. arrived well before dark, even though he had earlier made a heroic effort to stay at home with his wife! (Les has "the duty" at FDO on Saturdays this summer, so it was a bonus to have him at the dome tonight.) The alignment of the big scope was still good enough to locate Mars in broad daylight, so by 8:15 we had folks enjoying their first views of the red planet. For people who are surprized at how small Mars looks in the telescope, have someone hold a quarter up at a distance of a quarter mile. The quarter would be the same diameter as Mars is currently.

Mars is now falling behind the speeding Earth in its orbit, and is therefor noticeably smaller and dimmer each week. Even so, at 18.4", it is still larger than during an average opposition. Unfortunately, the dust storm that has been raging over the planet for weeks still continues. It is blocking out most of the surface detail we would otherwise expect to see. Even so, we all could spot the northern ice cap and the bright Hellas region tonight. Mars is noticeably phased right now, only about 93% illuminated. This makes getting your orientation in the eyepiece much easier. We did occasionally catch glimpses of some darkest areas of Mare Tyrrhenum, but rarely. Most guests from the public were disappointed at not being able to see more detail, but were impressed that such a storm can last for so long on a planet with such a thin atmosphere. Mars has now moved out to 47 million miles from us, but we do still hold hope of spotting its tiny moons again. No luck tonight, as there were just too many people lined up for a brief view. We spent a total of about 4 hours just on Mars!

With the dark skies rating about an 8 out of 10 (on FDO's high standards), it was difficult to have to spend so much time on Mars. The summer Milky Way was brilliant and beckoning loudly! So by about 11 PM we made our first attempts at DSOs (deep space objects). (Only to go back to Mars several more times later.) The only thing preventing the skies being a perfect 10 was some humidity that was scattering light. It wreaked havoc with the observers in the yard in the form of an early and heavy dew! Art had his 10" Dob set up, Steve had his Nexstar 5, and Hank (a frequent visitor from Woonsocket) arrived with his huge 20" Dobsonian.

While the lines stretched out the door of the dome Les entertained (and educated) the very large crowd out on the lawn. 16 satellite passes were counted, including two which were obviously in exactly the same orbit about two minutes apart. Folks asked why anyone would put two objects in the same orbit and we explained that sometimes one was a rocket casing and the other was a payload, or that a satellite broke in two. In addition to the large number of satellites, frequent meteors streaked across the sky. One meteor, verging on being a bolide, raced across Capricorn toward the eastern horizon. Everyone turned the right way saw a large falring globe leading a long trail. No matter how many Les explained that the big bright object was Mars and that the smaller red object "to the right" was Antares (ie Not Mars or in Greek anti-Ares), a new group would arrive to begin the process anew.

Our first deep space object was M4, the fine globular in Scorpius. Everyone was suitably impressed, but even greater wonders lay waiting. As time away from Mars permitted, we continued our deep space tour with M17, the Swan Nebula, looking very much like a contended Cygnet, and M8, the Lagoon Nebula. Both were spectacularly enhanced by adding our Oxygen III filter. Then it was on to the wonderful globular M22, and the rich open cluster in Scutum, M11. Both outstanding, causing many oohhs and aahhs from the crowd.

By midnight Comet Linear A2 2001 was positioned quite high in the east so we all went out to enjoy observing it first in binoculars. Since last week it has faded about one magnitude from 5 to 6, (no longer naked eye) but is still a fine sight in binoculars. It currently has just a hint of a tail. In the 16" the core was very bright, and the dust tail was easy to see, although we didn't notice the division in it that we saw a week ago.

Next it was on to the remote gas giants Uranus and Neptune. (Uranus is especially easy to locate in binoculars this year, just east of a neat alignment of 3 fairly bright stars just north of Gamma and Delta Capricornus.) At magnitude 5.7, and with the humidity induced haze, it was just a little too faint for us to spot naked eye, although we could see stars at least as faint overhead. The slightly damp air was steadying up well, and we were able to spy the moons Titania and Oberon. Ariel and Umbriel were too close to the planet to be picked out from its glare. Moving on to even more distant Neptune, we were impressed to see its one large moon Triton, with no difficulty at all. Despite its distance, Triton is brighter than any of the much closer Uranian moons!

At this point, about 1 AM, the crowds were thinning down to the real die-hards, and we began to observe some less "showy" DSOs. Ernie Evans requested a look at the fine planetary NGC6781 in Aquila. It has been bedeviling him in his 6" scope, as its surface brightness is very low. But in the 16: it was an easy target, large, round, with a definite crescent shaped portion on its lower half. Very nice.

We checked out NGC6760, also in Aquila, a moderately bright globular at magnitude 9.1 and 6.6'. We could partially resolved it at 203X. This was a feat that Doug had never been able to do in his 8" scope. Next was the peculiarly named "Phantom Streak Nebula", NGC6741, also in Aquila. Not much, really, only 9" x 7" and magnitude 12.0. The phantom streak evidently refers to the tiny ansae extending out from the nearly stellar disk, running ENE to WSW. Kind of a tiny Saturn Nebula. actually, requiring high powers to see anything.

With the summer Milky Way in Cygnus and Lyra now high overhead we decided to reposition the dome's bifurcated shutter to observe near the zenith. We first showed the lovely Albireo to some visitors who were still hanging in. Then, for contrast, Doug slewed the scope to the remarkable carbon star T Lyra. This is a very cool irregular variable which is perhaps the reddest star in the entire heavens. It is only about magnitude 9 right now, but in the 16" looked like a long burning ember of coal, a very deep red/orange in color. Really remarkable, and a fine contrast to the topaz and sapphire of Albireo. Earlier in the night, next to M17, we had looked again at the fine colored pair TYC 6265-656-1, about 1 degree NNE of M17. It is a fine gold and blue pair, very similar to Albireo, but not as brilliant.

We moved to the globular cluster M56 in Lyra. It is very often overlooked, but a fine sight in the 16", fully resolved at 203X. Doug asked the group's indulgence to observe the rich, but extremely faint, open cluster in Lyra NGC6791. This 9th magnitude cluster has over 300 stars, but none of them are brighter than about mag 13.5. So it is VERY difficult to pick it out against the rich Milky Way background. We finally saw it, but it ranked as this week's "smudge of the week". Sorry Doug!

Just east of the harp of Lyra is a fine pair of doubles often referred to as "the other double-double" It consists of the pairs HD 178911 and HD 178849. They are not physically related, but look like mirror images of one another, an easy and fine sight in any telescope. Everyone enjoyed this remarkable pairing.

Joe had been "frothing at the mouth", so to speak, to get to one of his all time favorites, M57, the Ring Nebula. Once again, it was WELL worth it. Joe, Steve and Doug all spied the dim central star wink at them once or twice. Doug remarked how well defined the knotting was on the northern end of the ring (no filter used). To the nebula's west we searched and found the VERY faint galaxy IC1296. It is fainter thatn the 14th magnitude, but shows up in many photos of the M57 area. Due to itrs faintness it is not many catalogs, causing it to be a frequently misidentified comet.

Epsilon Lyra, the real double double was next. Very cleanly resolved and brilliant in the 16", of course. And for a final DSO treat we all enjoyed the spectacular globular cluster M2 in Aquarius - one of the largest and brightest of the globulars. Just beautiful!

As we thought about closing down (now 3 AM) we looked outdoors and realized that Saturn and Venus had now risen in the east. So back went the dome shutter so that we could get this season's first look at the ringed planet. It was a very fine view in some remarkably stable predawn air. The rings were crisply defined although we could not sight the elusive Encke division. We could spot lots of surface cloud banding and 6 moons. Venus was next, at a dazzling magnitude of -4.1. It has 69% of its surface illuminated. We saw some areas of fine shading in the clouds along the northern terminator.

Last, and only slightly least, we caught Jupiter rising through the twilight, and of course had to take a look. Pretty mushy! But nice to see old Jove again. Another fine season awaits this giant! By the way, the little used "Black Bart's Lasso" worked fine last night as we were juggling the dome and shutter positions to view the Gas Giants. We created the "Lasso" to allow us to raidly close the dome shutter in an emergency. It is a long extension cord with peculiar "Jones" sockets which attach to the shutter controls.

With the stars fading from view we buttoned everything up, and in rather bedraggled (but very satisfied) fashion left Ninigret park at 5 AM. Then some long rides home!

-Doug Stewart

Leslie Coleman
Author:
Leslie Coleman
Entry Date:
Jul 20, 2001
Published Under:
Leslie Coleman's Log
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