1998 Feb 26   13° 39' 15" North
18:16:23 UT   67° 27' 30" West

4. Under Dark Caribbean Skies

Each night there was a "star party" on the official schedule. But I must say it would have been a sorry excuse for a star party had not fellow TACyon Leonard Tramiel and I been there. The tour director had arranged for one of the professional astronomers to lead the event. He interpreted this to mean pointing out a few constellations with a flashlight. Unfortunately, he didn't know his constellations very well (eg: he kept telling us that the stars of Corvus were part of Virgo). And fortunately, Leonard (and his precocious son Alex) was there with a ShortTube 80 and I had my Pronto. I think we managed to put on a decent show. But bigger scopes would have been nice. The wind would have put big Newtonians out of business but an SCT or a big refractor would have been useable.

I had some new equipment that I was using essentially for the first time. My rickety old tripod for the Pronto was replaced by a new Bogen 3221 with 3275 gearhead. As expected, it turned out to be immensely superior. No more shakes. Fast, easy motion in both axes. And the nifty quick release plate makes setup much easier and faster. IMHO, this is a pretty much ideal altaz setup for a small scope.

I wasn't able to buy solar filters for my binos nor for my Pronto (they tend to be out of stock just before eclipses, I guess :-) So I got some coated mylar and made my own with cardboard and tape. They aren't pretty but they worked. For the Pronto, I also rigged up a way to use a special glass filter that my Dad loaned me. It worked even better. Despite having to stop the scope down to about 55mm, the image was much brighter and sharper than with the mylar. I never actually used the Pronto's mylar filter, though it was nice to know I had a backup just in case.

My final bit of new hardware was a Sony Digital Mavica camera. My early experiences with it are detailed elsewhere. For the eclipse trip I took along 17 floppy disks figuring that would be way more than enough for a 5 day trip without having to copy them to a hard disk. So I left my Powerbook at home. As it turned out, I filled up 15 of the disks. When "film" is free, one tends to take a lot of marginal shots. And why not? Deleting the junk is pretty quick; missing a potentially valuable shot is forever. (On the other hand, as I found out when doing this web site, processing all the images can take a lot of time.) It worked just fine as a snapshot camera. But I sort of wish I hadn't had it during totality. It distracted me too much from the visual spectacle. Next time, no cameras.

The skies were really black. Except for the ships lights (which the capitan turned off as much as possible in our area at the bow) there was no light at all. There were some scattered clouds to make constellation hunting more interesting. They were literally invisible; we would look up and simply not see some stars that we knew were there (at one point we had Orion without his belt). With almost all my experience at 35N latitude (+/- a few degrees) the sky looked very strange. And, of course, the ship was pointed in different directions on each night. The result was a bit of confusion each night until I got oriented. But it sure was nice to have Orion nearly at the zenith. M42 looked almost as nice at 70x in my little Pronto than it usually does at Fremont Peak with my 12 inch LX200. OK, it wasn't as big and detailed but the really black background makes it so much prettier!

My first view of the Eta Carinae Nebula was from Australia in '95. But I was very new to observational astronomy at that time. I saw only the inner core of it. This time I saw it all. It is HUGE, at least twice the size of M42, though not as bright. What a marvelous sight it must be with a big scope!

In addition to the usual northern bright stuff we had a nice long look at Omega Centauri (NGC 5139) well up in a dark sky. Even in the little Pronto Omega Cen was gorgeous: huge and nearly resolved. What a sight it must be in a big scope. I've seen it from San Diego with my LX200 but it is so far down in the muck that it doesn't count. One of these days I'm going to have to take a big scope to the southern hemisphere! I also hunted down Centaurus A (NGC 5128); though I had prepared a chart I forget to bring it so I had to find it by memory and sweeping. It wasn't too hard with the really dark sky. I didn't see the prominent dark lane (after all I was using only 70mm) but I think Jay or Akkana might have.

One would think that the deck of a ship at sea would be a lousy place for astronomy as it would be difficult to keep the scope pointed as the ship rolled and pitched inthe seas. We had been told that the Radisson Diamond was a particularly stable ship. And so it turned out. At 70x and a true field of view of just about 1 degree (7mm Nagler) objects would stay in the field as the ship rolled. The motion was quite acceptable for astronomy at that magnification (higher powers would have been difficult) even though it was enough to (slightly) upset one's sense of balance. I would have thought the opposite. I wonder if other ships are significantly worse.

Everyone wanted to see Crux. But only those whose desire outweighed their need for sleep actually saw it as it didn't rise out of the cloudy horizon until well after midnight. Naturally, nearly everone (including our professional "leader") was confused by the "False Cross" that is somewhat larger and farther west and was easily seen early in the evening. Joan became our unofficial Crux expert. She was the first to spot it each night and had fun showing it off to everyone.

One of the passengers on our cruise was the famous physicist Freeman Dyson, "inventor" of the Dyson Sphere. Though he didn't speak at any of the lectures he did show up at a couple of the star parties on the bow. Leonard and I were in heaven. (Though I was kicking myself that I didn't bring one of his books to have autographed; I just bought "Imagined Worlds" the week before we left.) He got a little tour of the Centarus/Crux region with my Pronto. What fun, me getting to show off to such an eminent personage! He said that he hadn't done much amateur astronomy in his career but he seemed to know what he was doing nevertheless. He had no trouble seeing the dark lanes in Eta Carina (NGC 3372). At one point, he pointed to the western corner of the False Cross and asked about the obvious cluster there. I had no idea, of course, but I pointed the scope at it anyway. It turned out to be a magnificent sparse open cluster nearly as bright as M45. I later determined that it is IC 2391 (mag 2.5). It will forever be known to me as "Freeman Dyson's Cluster".

On the day after the eclipse I was messing around with sunset photos when Leonard remembered that the new Moon should be visible. And so it was, a beautiful crescent with a bright star just a degree away. (We had a little debate about which one the star was but since it clearly couldn't be Antares we settled on real Ares; a quick peek with the Pronto removed all doubt.) The Moon was only 30 hours old, nothing close to a record but very nice; the terminator was actually east of Mare Crisium. Except for an eclipse no one will ever see a Moon that new after having already seen it the day before!

Later that evening, I tried for Comet Hale-Bopp. I had had no success the day before trying to sweep it up knowing only the general area. But as this was one of the secondary goals of the trip I decided to make a more concerted effort since this would be my last chance (I doubt I will be alive 2400 years from now when it next returns to the inner solar system). I first saw Comet Hale-Bopp in 1995 from Melbourne, Australia nearly 30 months ago. It's not often that one gets a chance to see the same comet for 30 months!

So out came the charts I had cleverly prepared with Starry Night before we left home. Hale-Bopp was well above the horizon in clear, dark sky but it was in Dorado, an unfamiliar constellation whose brightest star is only mag 3.3. It tooks me a few minutes star hopping from Canopus just to get started. The comet was only about mag 9 so it wasn't going to just pop out in a 70mm scope even with the good dark sky. So I carefully star hopped my way from dim little triangle to obscure quadrilateral until the "lambda shape" marking the final field came into view. Studying my chart of the comet's path thru that field from day to day showed just where to look et voila! there it was, just barely visible with averted vision. Not much to see but as Mark would say, the hunt is as much fun as the kill. For me, it was nice to confirm that even us LX200-cripples can make do when we have to :-)

[ Continue ... ]

Bill Arnett; last updated: 1998 Mar 13