Jamaican observing

by Andrew Pierce

My wife and I just got back from 9 days in Negril and Montego Bay, Jamaica. I brought my 6 inch Intes Mak-Cass on an undriven german mount and 15x70 binculars. I didn't do a lot of deep sky observing, but I did enjoy excellent conditions for observing Mars.

Jamaica is at about 19 degrees north, a latitude just south of that of the Big Island of Hawaii. I brought a list of southern objects in Lupus, Norma, Ara, Scorpius Sagittarius, Pavo, Indus and Corona Australis, but I realized quickly that the area down near the horizon was not going to be favorable. Jamaica's July and August climate is similar to Florida or Hawaii with temps in the 80s, daily afternoon thunderstorms and clearing at night. There is always humidity in the air and clouds on the horizon at this time of year. In fact there was periodic distant lightning throughout all my observing sessions. Since I was observing from resort areas with lots of local light, the combination of moist eyepieces reflecting the lights and the poor horizon areas caused me to give up on deep sky observing after a couple of days. This is not to say that you couldn't do deep sky work in Jamaica -- actually it looked very promising in some ways. The binoculars were great for the Milky Way. I could see the bright stars in Grus pretty well. The sky is very dark in Negril, so if you can get away from local lights it would be very nice. In Montego Bay, where we stayed less than five miles from downtown, it was darker than our local dark sky sites. Even with poor transparency the Milky Way was easily visible at all times when a cloud was not directly in the way. The trick would be to find a safe site away from local lights (or getting your hotel to turn out a few lights) and perhaps observing in the winter-spring dry season. I think the western and southern parts of the country are drier than the area around Kingston. High altitude locations are extremely rainy, so an intermediate elevation might be best. Also its critical to take your scope and eyepieces out of any air conditioned areas for at least an hour before observing, so they can warm up to ambient air temps. If you don't do this dew will form instantly. Its nice to have a hair dryer in your room.

Now for the good news. The seeing was awesome. Presumably these are the same conditions that prevail in Florida, where many serious imagers like to operate. Every night I looked there were long stretches where I would rate the seeing as 4.5 or better on a 5 point scale. The worst seeing , which occured while a thunderstorm was passing to the south, was 3.5, better than I got from my yard last Saturday. The lower latitude realy hepls with Mars, not only because its almost 20 degrees higher in the sky than here, but also because it rises earlier and faster. Mars rose at about 8:30 and was 30 degrees above the horizon before 11:00 p.m. It wasn't getting that high here last week until almost 1:00 a.m. I wasn't using super high powers because the scope was hand driven but there was no visible unsteadiness at about 250x. Of particular note were the small hook of Sinus Meridiani, the gap between M. Tyrrhenum and M. Sirenum/Cimmerium and the north polar area..

In Negril there are security patrols that watch the beaches 24 hours a day. I got to know Paul, the guy on my part of the beach and felt comfortable leaving my scope out unattended for long periods at night. All the security guys wanted a look through my scope and actually radioed each other to come down and look at Mars. The boss patrol guy seemed to think he deserved a place in line ahead of Paul and the others. I got the same comment I got from the locals in Fiji during the last Mars oppsition -- they thought Mars looked like a moon. No one had any difficulty seeing the southern polar cap and the mare. I received some very warm thank yous for explaining a little about Mars and the Milky Way. When I asked PauI whether he had been taught anything about astronomy, he said he only learned the basics. My impression was that these guards knew as much as many people one encounters at public events here and had been exposed to less nonsense. Of course they were educated in a British system, not by listening to Art Bell.