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Science Journalism Outreach At Biosphere 2


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Location: Biosphere 2, near Oracle, AZ, about 50 miles north of home in Marana, AZ, about 3900 ft. elevation

Weather: 96F mid-day, 88F at sunset, 70F when we quit about 9:30 PM MST. Cloud free. 

Seeing and Transparency: I never got a chance to really evaluate conditions due to the nearly full moon.

Equipment:  10" Meade SCT on Celestron AVX mount, Mallincam Xterminator video system on the 10", 19" QFX LCD monitor.

First, a bit of background.  Several months ago I needed a quick replacement mount for my video scope and bought a Celestron AVX from Starizona: 1/3 the weight of the mount I was using and much more accurate in pointing, with an upgraded ADM dual saddle plate (Losmandy D and Vixen) replacement for the heavy scope.  Due to a wind accident at the Grand Canyon Star Party, the mount head ended up needing repairs.  All seemed great, but on Friday afternoon I was checking the AVX and the hand controller gave a failure indication.  I ran the system over to Starizona in the late afternoon and we found the electronic failure in the controller, but we also found that the ADM piece to carry the larger scope had been incorrectly machined and was causing a binding/lock-up on one axis.  For two and a half hours, Dean Koenig at Starizona re-machined the bad mechanical component and provided a new mount controller.  By now it was after 5:30 so it was a challenge to get to Biosphere 2, a waiting group of University of Arizona Science Journalism students, and get set up for the outreach.

I got there well after the other three had set up and scrambled to get up and running in the dark.  Eventually, all was assembled and the repaired system worked as it should have.  The moon was about 18 hours past full, so it hampered contrast quite a bit.  It rose just after astronomical twilight ended, so, while we did get to see the glorious Milky Way above us for about 45 minutes, the moon wiped all that out.  Unfortunately, our visitors arrived from dinner just after the best sky left us, but we did well with what we could work with. 

Don, Don, and Richard were rocking with the night sky and Saturn, M13, Albireo, and other eye candy.  After my belated alignment, I started in Sagittarius for M22 and taught the nature of globular clusters and the recent research, including some ground-breaking discoveries from Kitt Peak National Observatory, that seem to identify that there are three unique formation mechanisms for globular clusters.  The starting point of the genesis exploration begins with their age.  While the Milky Way is approximately 7.5 billion years old, the stars in these objects show ages approaching 12 billion years, making them Population III, the earliest generation of stars.  But if they are circling the Milky Way, how did the chicken-egg conundrum begin?  Initial internal studies showed supermassive black holes at the cores of the first globs studied, the indication that these balls of several hundred thousand to several million stars are the cores of early, smaller galaxies subsumed by the later development of the massive Milky Way.  But then, other globs show no such black hole core yet all of the stars are of approximately the same age, suggesting these globs evolved from a common, massive gas cloud, and their mutual gravity prevented their dispersion.  Finally, continued research showed some globs with disparate ages of stars, indicating that they were at one time smaller clusters of different sources, and in passing by each other became mutually attracted and formed a single entity. Three unique apparent mechanisms of formation.  Although there are less than 180 of these objects in extended elliptical orbits around and outside of the plane of our galaxy's core, other galaxies show 4,000 or more of these entities, leaving the mystery of what limits the Milky Way to so few of these objects?  This is similar to the question of why the Milky Way has fewer stars than its apparent mass and dimensions would suggest, so the more we learn, the more we see we need to study.

This is where the Mallincam Xterminator proved its usefulness in the demonstration.  Because of the tremendous reduction in contrast due to the nearly full moon in the dusty Arizona sky, the eye alone in an eyepiece sees hardly any detail.  The Mallincam, however, could be adjusted to overcome the environmental features and get the object into a teachable state.  In fact, with subtle adjustments, it was possible to pull out a few red giants from the internal structure and use the visual information to discuss stellar evolution.  These stars are mid-sized or smaller items, at 12 billion years old, and the larger stars have long ago gone to supernova state.  Thus, we’re looking at stars in globular clusters that are, for the larger of the remaining lights, near their end of life and have become red giants.  Impossible to grasp this in an eyepiece on a typical amateur telescope, but the magic of Near Real Time Video and highly sensitive CCD chips can open a new world of study and teaching.

After exploring the nuances of the aged, stellar retirement home of our globular cluster example, I went over to a young, star forming element called The Lagoon, M8, a mixed cluster with nebulosity.  Several million years ago, a gas cloud that had been invariant for over 13 billion years was excited by some dynamic event, possibly a near-by supernova or a passing giant star.  This event changed the local density of hydrogen just enough to kick-start a star to begin formation, whose ignition sent a pressure wave out and cascaded the process.  As a result, the Lagoon is a tight grouping of new stars being generated across the gas cloud like a glacial waterfall, and eventually, millions of years from now, all the hydrogen will be in new stars or blasted away by the dynamic pressure of the star formation.  This object filled half of the video screen with neophyte stars, but the normally gorgeous nebula in the remaining half of the view was wiped out by the moon glow.  With a UHC filter or much more tinkering with the settings on the camera I could probably have brought out more of the nebulosity, but I wanted to make better use of our limited time.  Pity, because it's a tremendous red cotton ball awaiting its turn to form stars.

Since faint fuzzies seemed to be less preferred targets with the bright moon, I went over to an open cluster in Cassiopeia, commonly called The Owl Cluster, nomenclature NGC 457.  It really does look like a pointillist impression of an owl spreading its wings.  The camera happened to be positioned such that it was upside down in the monitor, and one of my visitors immediately noticed the shape and said "It's a bat."  Yep, for Halloween in front of the house, that's what I do for the kids - show them "The Bat."  It has an alternative name in some cultures as The Kachina Doll Cluster.  Some years ago it picked up the name ET Cluster because of the movie, and even the movie Short Circuit cause it to briefly be called Johnny 5, after the robot in that movie.  With its spread wings, The Owl looks to be repeating Johnny 5's famous movie line, "No Disassemble!"  At about 22 million years of age all of its gas source seems to have been consumed and at nearly 9,000 light years distant, these are all giant stars, not much longer to live.

Moving back to Sagittarius, I tried The Swan, M17.  This is a large, red emission nebula which seemed invisible until I jacked up the gain way over the normal limits (usually I use AGC=OFF on Deep Sky Objects, here I set it to 5), set the Gamma 1.0 as though it was a dim object, and extended the usual integration time from 8 seconds to 20 seconds and son of a gun, The Swan exploded in the view.  So we discussed emission nebulae, with the UV energy from bright, new giant stars causing electron stripping from the hydrogen gas and other electrons racing in to balance the atomic charge, resulting in a hydrogen photon being released, billions of times a second and giving us a beautiful red and slightly blue reflective giant swan.  The neck of the swan is really a dust cloud hiding the giants causing the emission but require an infrared telescope to view.  That became a big hit as we defeated the Moon's attempt to hide the beauty from us.

We finished up on the Moon.  Awesome view, and we started with the explanation of the formation of our satellite about 4.5 billion years ago with the collision of the lost planet Theia with the Earth, and the resulting debris forming the lunar eye candy.  We went over the Grand Tack, with newly formed planets arranging themselves like sailing ships to achieve equilibrium.  At 3.5 billion years, this resulted in the Late Heavy Bombardment, the asteroids being disrupted and penetrating the inner solar system and leaving the evidence on the Moon in the form of the Maria, or lava seas, as the Moon was cooling.  We also looked at and talked about the later bombardment at about 1 billion years ago that left the ray craters as evidence of the now cold rocky moon.  We talked about a whole lot of other concepts like the tidal bulge and our length of day changing, the earth wobble and precession of the North Celestial Pole, the evidence of several other planetary collisions, and some of the lunar landings and their discoveries.

Listening to Don, Don, and Richard was great to hear as the education and introduction to the home universe was pouring forth.  All in all, a great night since at 4 PM or so I had no scope to use! 

Edited by Skylook123
Removed extra line feeds
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