by Andrew Pierce
A few months ago a local observer put his 8 inch Portaball telescope up for sale, on the very same day that a largish payment came in to my law firm. Serendipity waits for no one, so I puchased the scope, which I had long ago identified as a good candidate for a checked baggage travelscope, provided it was packed in the right case. The telescope is a truss tube reflector design where the primary is in a fiberglass sphere. The secondary assembly nests inside the sphere for transport. After some research I got a Pelican "Cube case" (#350) which is 20" x 20" x 20" on the inside and rugged as all get out. It's a little larger than needed, since the sphere is 15.5" in diameter, but extra foam doesn't hurt, especially given that I was going to have to check the case, not carry it on.
We had arranged a family trip to Puerto Vallarta for after Christmas, which was the first opportunity to put the scope and case to the test. This was a little risky as the outside dimensions of the Pelican case are about 23" x 22" x 22" or a little more. The allowable dimensions for regular checked baggage on most carriers, is 62 inches total for length plus width plus depth. My air carrier, Ted, had announced on its website that no oversize bags would be accepted for holiday travel to Mexico and Latin America so supposedly I wouldn't be allowed to check the Pelican case even if I paid the exorbitant $80 oversize bag charge. But I wasn't all that worried -- the air carriers don't seem to tightly enforce these rules plus the loaded case only weighed about 57 lbs, well under the checked baggage limit of 70 lbs. In fact my suitcase weighed more than the loaded Pelican case. Anyway I wasn't going to leave the scope at home.
All went well at the airport and the Pelican case was checked without comment, incident or extra payment. The base was in my carry-on and the eyepieces, trusses, SkyAtlas etc, were in my suitcase. We were at the La Jolla de Mismaloya hotel south of Puerto Vallarta. The first night, which was right after the full moon I spotted Canopus. The second night I easily spotted Comet Machholz with 10x50 binoculars. Its bright! I waited until December 30th when there would be some darkness before moonrise before breaking out the Portaball. The concierge at the hotel suggested I take the scope to the grounds of a nearby restaurant which is called the John Huston. I had to take a shuttle bus, which meant carrying the sphere in one hand, charts and truss struts in the other, with everything else in a backpack. This was doable.
The skies at this location, about 6 or 8 miles south of downtown were surprisingly dark. Puerto Vallarta has about 150,000 people but the area is surrounded by mountains, farms and the Bay of Banderas, not suburbs or sprawl. It looked like Fremont Peak on a good night in terms of darkness. The winter Milky Way was bright enough that I mistook it for a band of clouds. I'm sure there are many other usable sites in this relatively safe and accessible part of Mexico. The latitude is about 21 north.
Setup was a challenge as I had never tried it in the dark, much less in a grassy area without tables or chairs. It took about half an hour to get everything done, but it really should take about 15 minutes from arrival to full collimation and alignment with a little practice. The scope comes with its own Rigel finder, which has crosshairs, rather than circles, and draws power from a rechargeable battery in the sphere. I like the circles better because it is easier to see stars in it, plus I like being able to change the battery in the field so I may stick my regular Rigel finder on the base from now on. The Portaball has no finderscope and I haven't added one yet so it was dead reckoning with charts, 10 x 50 binos and the Rigel finder. This is what the builders of lightweight Dobs all want you to do, but I had never gone without a finderscope before. Not a problem as it turned out.
I quickly foiund M31, which was encouragingly bright and big. With a little more effort I foung M33, which stood out distinctly, and showed weak spiral struture at lower powers. Now that I knew I could find stuff, of course it immediately became cloudy. This was actually good, because I used the time to get well oriented to the southern sky, using the bright stars like Fomalhaut and Acamar that were still visible. There were hills to the south, so Achernar remained hidden. I decided to go to the Fornax galaxy cluster from Acamar by way of Chi Fornacis. On the way to Chi the bright galaxy NGC 1316 was obvious at 40x. I was also able to spot and ID NGC 1317, 1326 and 1341 in the area pretty easily. Did not see NGC 1310, however.
When I finally got over to Chi I saw the rather diffuse NGC 1365 and then stumbled across the very obvious NGC 1399-1404 pair. Also spotted and IDed NGC 1380 and 1387. NGC 1379 and 1381 formed a triangle with 1387.
I physically moved the scope to get a better view to the East and had a predictably spectacular look at M42. No filter neeeded here. I also saw the nearby Running Man nebula.
This gave me the idea to look for the Merope nebula which I had never confidently seen. I've often seen haziness around the brighter Pleiads, but never one that stood out or had a shape that proved it was real and not just an optical artifact. Well the Merope nebula couldn't have been more obvious, a triangular comet like shape that trailed away from 23 Tau. There was no no similar large structure around the other equally bright or brighter stars, although in retrospect I probably could have IDed other bits of nebulosity as the other stars did not look equally pristine. I have to attribute this success to the Zambuto mirror, the Portaball design, the Puerto Vallarta sky where Taurus is at the zenith, and my nice Orion Lanthanum 17 mm EP.
Temperatures were in the 70s and there was some local light pollution. One feature of the Portaball is that you can rotate the entire scope, which I did while looking at one of the Fornax galaxies in order to turn my back on some of the restaurant lighting.
I had to leave early because of family considerations. As I was packing up some workers from the restaurant came down to see the crazy American. They had one question -- did the stars look different because the earth's rotation was affected by the tsunami (actually the earthquake). I told them a Dob was not the type of instrument to see that kind of effect.
Posted on sf-bay-tac Jan 09, 2005 19:27:34 PT
Converted by report.pm 1.2 Jan 25, 2005 20:29:36 PT