The plan was to spend Saturday and Sunday night in Parkes, the nearest town to the telescope. Alas, there were no rooms at the inn on Saturday night, but Forbes had rooms. And it's only 33 km from Parkes, and an additional 25 km to the telescope. Some other visitors in the motel suggested getting there early - advice also from the Open Days web site. So I did just that - on the road about 08:30, reaching the telescope a little after 09:00.
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| Tour queue at 09:27 | Tour queue at 11:01 |
The telescope tour line grew as the morning continued, though it was not as bad as it was on Saturday, when an estimated 1500 people toured. Each group had about 12 people. There was also a minimum height requirement, as some of the stairs were steep, and holding onto the rail was essential. The poor man on the left of the left photo had his 2 children, and the little girl was too short, so he missed out on the tour.
This gives a good view of the whole operation. The building below
the dish has three levels plus the telesecope mechanicals above.
The ground floor is the kitchen area (and probably some plant).
The next floor is for the astronomers, and the top floor holds
the telescope control and signal processing equipment. The line
of people waiting to go on the tour is at the right of this image.
There are two plaques on the base of the tower to mark the inauguration of the telescope.
This is the other side of the telescope from the above photo. The
tour starts by climbing the temporary stairs inside the cloth
structure in front of the people with backs to camera. There is
a tour group at the top of the temporary stairs; the set of stairs
leading to the top level are a permanent part of the structure.
The guide said that if we were unhappy to continue up, we could
enter the telescope building from a door behind the assembled
group of red hats. I don't think anybody from our group used it.
It's not all that clear, but the flat surface below the silver plate
about mid image is the surface on which the telescope rotates.
It is still in excellent condition, given that it's 48 years old.
This is just as well, because replacing it would appear to require
dismantling the entire telescope, as it carries the weight (320 tonnes
for the telescope, and 400 tonnes for the counterweight!).
The silver plate is a brush arrangement to remove debris from the
track when the telescope rotates. The horizontal cylindrical shape
behind the brush is one of the (four, I think) electric motors and
gear drive reduction units which rotate the telescope.
This is the azimuth control section. It tilts the telescope.
The big object in the middle is the locking pin used to secure
the telescope in the upright position. Currently manually operated,
but it is planned to be electrically operated, and thus allow
remote operation. The man is the tour guide.
In the same area as the last photo, but showing the teeth which are
part of the telescope base, and which are used to tilt it. The top
of the image is the counterbalance - cement blocks filled with lead.
As it weighs more than the telescope, any failure of the drive
mechanism results in the telescope naturally returning to the
straight up position, where it can be locked in place if needs be.
This is a hydraulic system which allows the telescope to be lifted
off the rollers upon which it rotates. The reason is to prevent the
rollers developing flat spots, which would decrease the accuracy
of positioning, and seriosly degrade the performance.
Looking roughly east, or south east, the nearest telescope is
now retired. It used to move along railway tracks to allow
interferometry operations, but has been out of service for many
years. The tree on the far left has grown inside the railway
tracks, which gives an idea of how long it has been out of service!
The dish to the right is a new design, and will be covered later.
The lab and accommodation wing. The tents are for various Open Day
activities, including the local astronomical society with telescopes!
Optical ones, that is.
The Visitor Centre, and a few additional tents.
Apollo 11 Plus 40
Forbes
Inside