Moorea, April 12 to 20, 2007

by David Kingsley

There are no direct flights from San Francisco. I left Thursday April 12th at 7:30 am on a flight from SFO to Los Angeles, had a three hour lay over, then transferred to Air Tahiti Nui for a 7 hour flight to Tahiti. The flight arrived at Papeete, the capital city of Tahiti just after sundown on Thursday. We had beautiful views of coral atoll islands as we flew in at sunset. Stepping off the plane into warm, humid conditions, thousands of miles from the nearest continent, with most conversations around me in Polynesian or French, I immediately felt like I was in a different land.

Thursday night: I stayed at a small guest house 15 km south of Papeete Thursday night (Chez Armelle). Broken clouds at 8 pm, clearing to beautiful view of the southern Milky Way and LMC. Spent two hours with binoculars on reclining beach chair, relearning southern constellations with waves lapping at my feet at the edge of the coral lagoon surrounding the island Tahiti. Beautiful views and setting, with night time temperatures around 80 degrees. Local time was 3 hours earlier than current time in California, and I turned in about 11 pm after the long day of travel.

Friday: Took the ferry to the island of Moorea on Friday, located about 11 miles to the west of Tahiti. Picked up a rental car at the ferry terminal and drove 25 km to the largely undeveloped south side of Moorea. (The entire island has a population around 8000, and most live on the Northern coast). There I checked into Residence Linareva, a small bungalow complex that I picked because it faces the southern coral lagoon. This turned out to be a great place to stay. Friendly management, very nice air conditioned unit with queen bed, bathroom, kitchen, fridge, microwave, and covered outside porch. Just a few steps to the beach. Freely available bikes, kayaks, snorkeling gear, and a long dock stretching into the lagoon. There were ground light on at the complex at night, but I found I could position a telescope behind a small shack halfway out the dock. The shack shielded me from the lights on shore, and I had a perfect horizon to horizon view to the east, south, and west (the key directions for a trip to the Southern Hemisphere).

I don't think a dobsonian telescope have worked well from the dock. There was a relatively small space behind the shack, and it would have been difficult to stay in the shadow of the shack, while not falling off the dock when swinging a dob around from East to West. However, I had brought a Nexstar 8 inch SCT as a travel scope, which turned out to be an excellent choice for the observing conditions on this trip. The OTA was compact and light weight enough to fit the carry on regulations of American and Air Tahiti airlines. The tripod and fork arm are also lightweight. I had no problem checking each into regular luggage and still meeting the weight limits of less than 50 pounds per bag. The eyepiece position made it possible to sit comfortably throughout the night with whatever chairs I found at local sites. The scope fit easily in small spots like the dark shadow on the dock, with an eyepiece position that was easy to keep shaded from local lights. The tracking and GoTo also made it possible to find things even when broken clouds obscured parts of the sky. For eyepieces, I used a 35 mm Celestron ultima, a Vixen 24 to 8 mm zoom, and a 5 inch AP planetary. I also mounted a five position Atik filter wheel between the scope and diagonal. That made it easy to dial between five positions when looking at any object, including: 1) no filter, 2) Lumicon DeepSky filter, 3) DGM optics Narrow Pass Band filter, 4) Lumicon OIII filter, and 5) Star Spectroscope diffraction grating . Between the tracking, the goto, the zoom eyepiece, and the instant choice of filters at the eyepiece, I was able to make the most of out the observing time I did have each night, and explore each object I looked at with a broad range of magnifications and filters.

Friday night: Observed from 9 pm to 2:15 am. It was windy at times early in evening. However the pattern was off and on gusts, so it was always possible to get a steady view within a minute or so of staring in the eyepiece. Spent much of the session tracking down old favorites around Eta Carinae and revisiting the same objects that John Herschel had observed during sweep 543 on Feb 4, 1835 from the Cape of Good Hope. This is the night he described in his diary as the most sublime of his entire astronomical career. I had tried observing this same list of epiphany objects from Australia last October, but many of the objects were still low in the sky at that time of year. Here in April, the highlights of the southern Milky way through Vela, Carina, and Crux were perfectly displayed, and make a spectacular display of some of the best nebula, dark lanes, and open clusters in the sky.

Saturday night: Pouring tropical storms all afternoon, and cloudy every time I checked from 7 to midnight. Although I got no observing in this day, I had a great time reading and catching up on notes. I had with me a chronicle of Captain Cook's voyages in the 1700s, Darwin's notes on Tahiti and coral islands from the Voyage of the Beagle, and a DVD full of Herschel's original sweep notebooks, original sketches, and manuscript notes from his years at the Cape of Good Hope (see web links below). The juxtaposition of three great British explorers was fascinating. Cook charted vast areas of the physical earth on three epic voyages around the world from 1768 to his death in Hawaii in 1779. Sixty years later, Darwin revisited many of the same locations originally described by Cook. His notes and observations from the Voyage of the Beagle led directly to both a theory of coral island formation, and a grander theory for the origin, diversification, and interrelationship of all living things on earth. At the very same time Darwin was charting living forms on the Beagle, John Herschel was exploring the larger universe from the Cape of Good Hope, using the same 18 foot reflector that he and his father had originally used to sweep the heavens from the Northern Hemisphere. The explorer of the universe and the explorer of life actually crossed paths during their epic trips. The Beagle stopped at Cape of Good Hope in June of 1836, and Darwin and Herschel met and had dinner together during the stop. Four months later Darwin was back in England and began his first secret notebooks on the transmutation of species the following summer. In March of 1838, John Herschel packed up his equipment and returned to England to begin work on a huge tome of his Southern Sky observations, followed later by a comprehensive list of all known objects in the heavans organized by Right Accession (the General Catalog of objects, a direct precursor to the "New General Catalog" later prepared by Dreyer).

Sunday: More occasional rain showers during day, but I had a wonderful time exploring the south side of Moorea by bike, and kayaking out to the fringing reef for views of both Moorea and lots of coral and reef fish. Despite pessimistic forecasts, I was delighted to see clear skies by an hour after sundown. I set up again on the dock, and began tracking down a list I put together of the the original NGC objects originally discovered by John when he first set up the 18 foot telescope in the southern hemisphere. Wolfgang Steinicke's "Historic NGC" is a great resource for assembling this kind of observing project. On Saturday, I had sorted the spreadsheet by observer, discovery year, and discovery month, and found that John had made 35 original deep sky discoveries in March and April of 1834. The list included a bit of everything, including 7 galaxies, 3 planetaries, 16 open clusters, and 9 emission nebula. All were obviously well positioned for observing in April, a hundred and seventy three years later. I had one of the most enjoyable nights of my own observing career going through this small history project under ideal conditions. Temps were warm, breezes were gentle, the sounds of distant surf on the outer coral reef mixed with the quiet lapping of water in the inner lagoon, and the reflection of Sirius could be seen stretching like a faint light path all the way from the horizon, across the coral lagoon, to me on the dock quietly sketching and taking notes behind the eyepiece of a telescope. I observed from 7 pm to 2 am, finishing with a bunch of globular clusters and eye candy only visible from the Southern Hemisphere, and then watching a bit of a shadow transit on Jupiter. Seven hours in observing paradise, and a night worth the entire trip.

Monday to Thursday: Drove from southern Moorea around the rest of the island to the Gump Research Station on Cook's Bay located on the North side. The conference on vertebrate evolution began Monday evening, and was organized with morning and evening sessions the rest of the week. That left afternoons free to explore the central valleys of Moorea, visit archeological sites from the original Polynesian culture, and snorkel both inside and outside the coral fringing reef. The evening sessions of the conference usually ended between 11 pm to midnight, leaving relatively little time for observing. However, on Tuesday night I set up on the edge of Cook's Bay and observed from midnight to about 2 am. On Thursday, we had a Polynesian banquet and fire dance instead of an evening session and I observed from about 9 pm until skies clouded over at 11 pm. I used the four hours of observing time on the North side of the island to track down many of the objects listed on the relevant southern sky pages of the Pocket Sky Atlas. On my last night, I also looked up a couple of objects that John Herschel had tracked down on his very last sweep in the Southern Hemisphere (sweep 810, Late Jan 1838). The giant 18 foot telescope effectively ended its long and illustrious career that night. John considered his observational career complete at the end of the Cape of Good Hope trip, and he never set up the famous telescope again after returning to England. He pointed the scope to interesting objects on his last night as a deep sky observer, however. The planetary NGC 3132 is a showpiece object, and John considered his view of the NGC galaxy 3250 that night the best he had ever had of that object. Both were obvious and interesting in the 8 inch scope, and fitting objects for a last night session before I had to pack up for the return trip to California.

Friday: After the last morning session of the meeting, I returned the rental car on Moorea and took the ferry back to Tahiti. Five of the scientists on the ferry then decided to hire a van in Papeete to take us out to Point Venus and Mataavi Bay. This is the location where all of the early European explorers used to anchor, including Captain Cook's Endeavor in 1769, and Darwin and the Beagle in November 1835 (Darwin's first stop after the historic visit to the Galapagos a month earlier). Mataavi Bay is still a beautiful spot, with a long black sand beach on a point of land protecting a beautiful inlet on the island of Tahiti. On Friday evening, there were lots of local inhabitants swimming along the beach, or paddling outrigger canoes in the coral lagoon. I walked out to the end of Venus Point, visiting the same spot where Captain Cook had tried to time the transit of Venus on June 3 , 1769. He had perfect conditions that day, but found that the atmosphere of Venus made it difficult to obtain precise times for ingress and outgress. Venus transits come in pairs every 110 to 130 years. Cook's trip to Tahiti had been motivated in part by the fact that astronomers would not get another chance in their lifetimes to observe this event. The next pair of transits occurred in 1874 and 1882. We are now in the middle of just the second pair of Venus transits to occur since Cook's original voyage. A few TACOs traveled to Europe to catch the first of the current pair in 2004. The next one should be visible from North America on June 6, 2012, offering another chance to link current amateurs with a long and interesting history of human exploration of their place in the universe.

Although Venus transits are rare, the Southern Hemisphere is there for everyone. This is the fourth time I have been able to observe south of the equator. All three previous trips have been to Australia, including 7 days in the Flinders ranges with a 105 mm refractor (observing trip with Albert Highe and Bob Jardine, April 2005), 6 days at Timor cottage with a 12.5 inch Dob (observing trip with Marek, followed by science conference in Sydney, Aug/Sept 2005), and a 10 day trip with a 14.5 inch Starmaster at Timor Cottage, Bourke, and Wilber cottage (observing trip with Albert Highe, Bob Jardine, and Rob Hawley, October 2006). I greatly enjoyed this most recent trip to a very different location with an 8 inch scope. Moorea is other worldly in daytime beauty, and offers a chance for kayaking, snorkeling and exploring that are worth the trip alone. At 17 degrees south, it has much better vantage point for southern sky observing than either Hawaii (20 degrees North) or Costa Rica (10 degrees north). However, Australia is still further south (31 degrees). The extra latitude is a big advantage for trying to get any observing done in the SMC or LMC in April. I was able to observe the Tarantula nebula on this trip, but the LMC was usually low on the horizon by the time skies would clear in French Polynesia. Skies in Moorea were very dark, but the humidity was substantially higher than in Australia. I took SQM meter readings of around 21.4 on this trip, (with the bright band of the Milky Way dominating the sky at the time). For context, that is 0.8 mag darker than a typical night at Coe or Fremont Peak, roughly similar to readings I have recorded on nights at CalStar, but still a half mag brighter than my darkest readings in Australia. Moorea is by no means a budget destination, but flight costs were a couple hundred dollars cheaper than going to Australia. Luxury hotels on Moorea can reach astronomical rates for honeymoon bungalows built out over the lagoon with glass floors overlooking coral reef fish ($1800 a night at the Sheraton near Cooks Bay). However by bypassing the tourist areas, I was able to find excellent accommodations for $100 to $120 per night.

For pure astronomy, I think Australia is still the better destination. It's darker, drier, further south, can be reached by direct flights, has cheaper food and accomodations, and has some places to stay were telescopes are already available on site. However, I really enjoyed the enormous change of pace and place in Moorea. The culture, setting, language, food, and history are very different than both the US and Australia. The coral island setting and scenery are spectacular, and the mixture of both daytime and nightime activities make a fabulous place to visit at the end of a winter and rainy spring in California.

Useful resources:

1) Wofgang Steinicke's Historic NGC:
http://www.klima-luft.de/steinicke/ngcic/Expl_Hist_NGC.htm

2) Partial On line version of John Herschel's Cape Observations:
http://www.ngcic.org/Historical_Record/Corwin/1847AO-1_JHerschelCapeObs.pdf

3) Unbelievable archive of original William, Caroline, John Herschel observing notebooks, correspondence, sketches, manuscripts; all available as a 3 DVD set from the Royal Astronomical Society: http://www.ras.org.uk/index.php?option=content&task=view&id=78 http://www.ras.org.uk/images/stories/ras_pdfs/CD-DVD%20advert.pdf

4) Residence Linareva on Southern Moorea:
http://www.linareva.com/introA.html

5) Richard Gump Research Station, Cook's Bay, Moorea
http://moorea.berkeley.edu/

---David Kingsley