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I had an opportunity to visit Lick Observatory on Mount Hamilton near San Jose on August 28, 2003 with a professional group (the local IEEE optical society).  This was within 48 hours of the time of closest approach of Mars to the Earth, the closest it has been for about 60,000 years (the last time Mars was this close our ancestors were sharing caves with Neanderthals).  The professional group tours are limited and offer a much more detailed tour of the facilities than the regular visitor tours.  We had a working astronomer as our tour guide.  I thought I would share some pictures and an account of my visit with my fellow amateurs.  These are all hardware pictures.  I wasn't able to get any pictures of astronomical views.

When we arrived at the parking lot of the observatory there were television trucks and commentators talking about the wild fires in the surrounding hillsides as well as fire fighters there using the high location as a command center.  This made for a rather dramatic backdrop to our tour and made the local astronomers somewhat jumpy.  While we were there a fire alarm went off and every one of the buildings had to be emptied.  It turned out that someone had burned a hamburger (we met the culprit later at the 4 meter telescope) and the smoke set off the alarms.  There was some talk in muted voices about an observatory in Australia that was destroyed by fire the prior year.  During our viewing through the old 3 foot refractor one of the daughters of the astronomer giving the tour called him to make sure he was OK and whether they were going to evacuate the mountain.

Mount Hamilton is about 4200 feet high and takes about an hour to drive from San Jose.  The observatory is owned and run by the University of California and there are several telescopes on the site.  There are about 50 people that work on the mountain full time in addition to the visiting researchers.   Most of the workers commute in from the Bay Area.  This is an active research observatory and it appears that several of the telescopes are being used for sky surveys to find extrasolar planets as well as supernova in distant galaxies.  Research proposals can come from any of the Univ. of California campuses and can include researchers that are not U of C researchers as long as the primary name on the proposal is a U of C researcher. 

Power on the mountain comes from the grid although they have their own generators with sufficient capacity to keep the observatory going even when, as is quite frequent, the external power goes out.

It is possible that an amateur with an interesting idea who worked with a U of C researcher might even be able to get some time on one of the Lick telescopes.  Scheduling is very tight and most users only get a few days to do their work in a year whether the weather permits the completion of the work or not.  Lick headquarters is in Santa Cruz where there are over 100 people.  Many of these people do technical support for the telescopes including building sensors, optical coatings, etc.  It would be a very interesting trip to visit the support laboratories at UC Santa Cruz sometime.

The observatory was begun in 1882 although it officially opened in 1887.  The oldest telescope on the site dates from the 1870s and was moved to Lick from England in the 1890s.  Lick Observatory was originally built with funds from James Lick an early California settler who owned a large amount of the city of San Francisco at the beginning of the California gold rush.  James Lick is buried in the cement pier that supports the 3 foot refractor telescope that we used for viewing the stars.  This observatory was the first in North America to be built in an (at the time) isolated and elevated location to get a better view of the night sky.

Almost all of the astronomy done at Lick is with instruments although there are a few telescopes used for visual observation, mostly for visitors (the 3 foot refractor is the most popular of these).  Many years ago the astronomers from Lick prevailed on the city council of San Jose to use low pressure Na-vapor street lights since the limited spectral lines of this light could be easily separated from the star light they were trying to see.

We looked at two of the telescopes while we were on the mountain.  The 4 meter telescope was completed in the 1950s and at the time of its completion it was the second largest reflector telescope.  It is now among the top 25.  This telescope is the largest on the mountain but not the most recent.  The mirror was ground and coated on the site in the basement of the domed shaped observatory.  Every three years they strip the old and now somewhat dirty aluminum layer off the mirror and recoat it in the basement of the building.  Over 10 years were spent polishing and preparing the mirror.  The final polishing steps involved using rouge on wine corks to work small imperfections out of the glass.  This telescope is really awe-inspiring with the heavy metal of its construction.  It rotates in one axis on a giant oil-bearing yoke.  The 4 meter telescope also contains adaptive optics to adjust the lenses to the atmospheric conditions.  In order to create a stable visual object in the sky to focus on for the adaptive feedback circuit the telescope has a 12 W laser system consisting of a YAG laser driving a dye laser whose light can create an artificial star in the atmosphere.  Needless to say they have to check with the Bay Area air traffic system before firing up the laser to make sure they don't blind any pilots on approach.

When it started to get dark we walked back to the visitor center which is the original building at Lick.  That is where the original telescope from the early 1880s is located as well as the 3 foot refractor.  This is probably the largest refractor telescope in the world.  Shortly after its construction astronomers moved to reflectors since they could more easily build good large telescopes with reflectors. 

The 3 foot refractor building is a tribute to 19th century over-construction.  The telescope pivots around a central pier supported by Licks tomb.  Axial rotation of the telescope appears to be via old DC motors.  The control unit for the telescope looks like it came from the set of a 1930's horror show (all that is missing are the arcing Jacob's ladders).  The most unique feature to this observer was that the telescope is very well balanced at the pivot and visual observations are made by an observer on a movable floor who personally moves the telescope. 

The floor, which appears to be about 50-70 feet across raises and lowers via hydraulics, actually raises and lowers 16 feet to allow observation at different azimuth in the night sky.  Our group of about 40 sat on a single row of chairs around the dome at the highest level of the observatory floor but separated from it by a not too substantial guard rail (it was made to be unhooked to allow access to the floor).  To access the floor and look through the telescope required walking over to a stairway that went along the moving floor.  The railing was unhooked to allow the viewer to access the observing floor.  Only about 10 visitors were allowed to be on the floor at a time so they would not overwhelm the hydraulic system that supported the floor.  As a consequence we cycled about 4 times through our group of visitors for the objects that we viewed that night.

The complicated viewing arrangements meant that every viewing took a half hour to forty-five minutes between objects.  We saw two extrasolar objects before looking at Mars.  The first was M-13 a globular cluster of stars in the Milky Way that is estimated at over 10 billion years and which predates the local galaxy.  These are fascinating roughly spherical bunches of millions of stars whose density increases proportionately to the distance from the center.  The stars themselves are sub-solar mass stars since any star with a mass of our sun or greater would long since have burned out.  There are probably a lot of old brown dwarfs and burn-out neutron stars buried in these clusters of stars.  These stars also don't contain much of the heavier elements since they were formed in one of the earlier star generations when elemental evolution was at an earlier stage.

The second object we looked at was the ring nebula.  This is a beautiful green colored object that is made from glowing gasses driven off during an explosion of a small white star (neutron star?) at the center which is also the source of the energy driving the glow.  The ring of gasses contains oxygen whose spectral emissions are the source of the green color in the glowing ring.  This ring is rapidly expanding and will eventually blend in with the background space in a few thousand years.

Finally about 11 PM we were able to look at Mars.  By this time the planet was well over the horizon and the atmosphere had stabilized.  After a while I had my turn at the telescope.  The view was astounding!  I was able to make out the southern polar cap as well as several features on the surface (impact ejecta primarily).  Its one thing to see a Hubble space telescope image of the Martian surface but quite another to see it yourself so close through a large telescope lens.  This has to have been one of the most dramatic views through a telescope that I have ever had and might ever hope to see!

Anyway, I am glad to have an opportunity to share my experience.  Please let me know if you have any comments or questions.  Best wishes!

Tom Coughlin