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by Jane Houston
The spectacular shapes of Uluru (Ayers Rock) and Kata Tjuta (The Olgas) dominate the surrounding flat desert of central Australia. They are the culmination of geologic events stretching over millions of years.
Human settlement in this region dates from at least 50,000 years according to the most recent findings. Earlier still, 900 million years ago, most of Central Australia lay at or below sea level, forming an arm of the sea known as the Amadeus Basin. 550 million years ago this basin was raised up, squeezed, crumpled, then buckled into folds. These folds fractured along faults. The country uplifted and was subjected to erosion. Ayers Rock and the Olgas are the result we see today.
Ancient Australian Aborigines inhabited and worshiped here. They lived and loved beneath the stars for thousands of years before the invention of light pollution. They slept and dreamt under the stars. They took the night stars for granted. They embraced the darkness. It is woven into their culture through song, dance, ritual, art and myth.
The Magellanic clouds and dark patches we call dark nebulosity figured into aboriginal mythology. Some say the Coal Sack is a watering hole, surrounded by the ancestral heroes. The great stars Alpha and Beta Centaurus, and the beautiful stars of the Southern Cross, for example, represent these heroes.
The Magellanic clouds appear as twilight ends. The LMC is highest and 22 degrees above the SMC. It is difficult to discern the barred spiral shape at first. Most of the light and mass of the LMC is concentrated around the bar, which comes alive with hundreds of star clusters and nebulous patches. A month of Ayers Rock nights would not be enough to do observing justice. My five nights will offer but a glimpse!
The single most interesting object in the LMC is the giant HII region NGC 2070, the Tarantula Nebula. Also called the 30 Dorado Nebula, it is a vast area of ionized gas 900 light years in diameter. Its mass is 500,000 suns. It owes its power to over 100 supergiant stars. To me the round dark patches, circled by wispy arms of gas, are beautiful and flower-like. I found myself returning often to the Tarantula.
The Keyhole Nebula or Eta Carina, NGC 3372, has dark rifts dividing the petal-like sections of the massive nebula. Eta Carina, the star, is involved in the most interesting transformation. It is an exceptional class of supernova, surrounded by dense by dense nebula, which is expanding at 500 km per second. Through the 20-inch, 15-inch, and 12.5-inch telescopes we could observe ropy dark knots in the nebulae on either side of the unstable yet most intriguing star. These objects, both star and nebulae are unsurpassed in beauty, complexity, and color. The most magical objects I have observed and photographed. Our group of 32 amateur astromers all agreed. This was THE best of the best.
I could go on and on. (And will - have no fear!) Omega Centauri, the spectacular cluster, looks like exquisite lace through the two 20-inchers - one 20 inch Obsession carted 2000 miles from Sydney to Ayers Rock to join our merry band of star seekers! Perhaps the most spectacular sights so far on my first night as an astro-tourist is the arm of the Milky Way embracing us overhead from horizon to horizon - twisting in unusual ways as the night progressed and the earth moves. Or maybe the Southern Cross and Coal Sack dark rift overhead - forming the shape of the great wingless Emu as it continues down to our more familiar Scorpius and Sagitarius Milky Way starfields. Or perhaps it was Venus and Mars, rising and setting on opposite horizons, as if performing a slow tango on the ecliptic plane.