Serious Apprehension

Today is the day I will close my eyes, cross my fingers, and press a button.

Old and New PLC's
The old and new programmable logic controllers installed in side the control cabinet.
If all goes well, 700 tons of steel and aluminum will move at that button press. the Keck 2 dome will rotate and I will be able to breathe again. There is just a little apprehension here. Replacing the controller that commands the motors and brakes has been my major effort for the last couple months. A great deal of time has been spent testing and retesting the software in the new controller.

Further tests will open and close the shutters. If anything this part is even more worrisome. The controller is responsible for releasing the brakes on the shutters. If the brakes were to open without motor power the shutters will be able to simply run downwards.

Fortunately they will not fall, but they can run downwards to the hard stops rather quickly. There will be a tech stationed at the shutters with a finger poised over the e-stop button during these first tests. The button blows the dome main breaker, which removes power from the brakes, causing them to close.

A brain replacement is fraught with opportunities for error. Currently the old and new PLC’s sit next to each other in the cabinet, installed last week. Monday morning I will remove the old one and slave the I/O cards to the new controller.

Then the testing begins.

On Time Again

So last month the observatory clocks decided is was 1995. A software bug interfered with proper decoding of the GPS time signal. For a few weeks we got by by kludging two of the old clocks together in a creative way to provide good time for the telescopes.

The new clocks are now fully online and operational. I ran one of the new time servers for a couple weeks while keeping the old time servers in place as a backup. These have now been removed, with a second new unit installed as an in-place spare.

Hopefully this will keep everything on-time for the foreseeable future. Two new precision clocks, Microsemi SyncServer S350’s, time accurate to microseconds.

Meantime there may be a fix for the old equipment, a new GPS module by Heol Design. We have one on order to try. It would be a shame to throw out these very nice clocks.

Observatory Clocks
Two new GPS time servers installed in the Keck 2 computer room

WHAC Visits Subaru

Over the past few years the West Hawaii Astronomy Club has visited nearly every telescope on Mauna Kea. One glaring exception to this is Subaru, the 8.2 meter telescope belonging to NAOJ.

Subaru Telescope
The sun glints over the tall Subaru telescope enclosure
Subaru… Check.

Subaru is the only telescope with an active tour program. By making reservations ahead of time you can visit the interior of the facility with a guide. This made making the arrangements for a tour quite simple, even when the observatories are worried about events on the mountain. We did quite well for tour guides, Rieko Murai and Josh Walawender made the tour a bit better than the usual tour. Josh is well known to the local amateur community, bringing his own small telescopes to observe at the VIS.

The limit for any group visiting the telescope is eight due to practical considerations such as safety. Thus I had set up two tours, using both the 10:30 and 11:30 slots. This allowed most of the club an opportunity to visit the telescope. This did mean we were unable to enjoy the experience together. While we waited for our later tour I led a short walk to some interesting geologic features and one of the ancient ahu that are near the road.

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Venus and Jupiter

Over the next two months the two brightest visual planets will dance in the sunset. Jupiter and Venus make for a brilliant pairing. With Venus shining at -4.3 and Jupiter somewhat dimmer at magnitude -1.9, the two are already quite obvious in the evening sky. Jupiter will swing just north of Venus approaching to within 0.3&deg on June 30th. The pair will separate slowly after that and disappear into the sunset glow together.

Around June 30th the two will be easily close enough to bee seen together in the low power view of amateur telescopes. It makes a fascinating sight to see the two planets together in the eyepiece.

As an added bonus the planet Mercury will join the pair around August 3rd, the trio forming a nice triangle of bright planets low in the sunset.

Not a Bullet Hole

When the police reports hit the web we were all a bit worried. A bullet hole reported in a door at Subaru Observatory. The photos circulated shortly after the reports did not help, it really looked like a bullet hole in the door.

It looks Like a Bullet Hole
A hole in an exterior door at Subaru, mistaken for a bullet hole.
While the news circulated Sunday it was all conjecture and accusations flew everywhere. The threats made against the telescopes were discussed. Protesters protested their innocence, and claims of “false flags” and inside jobs were made on Twitter and Facebook. The national news picked up the story and reports could be found all across the web.

Arriving at the summit Monday morning we took the few minute walk over to Subaru to look at the door in question.

This was not a bullet hole.

Plumbing Fixture
The plumbing on the adjacent wall that made the hole at Subaru.
We had gotten word over the radio a few minutes before that it was not a bullet hole, but there was no explanation as to how that had been determined. A close look and I had to agree, the hole looked wrong to me. I do have a fair amount of practical experience in making real bullet holes. It was clear that the door had slammed against a bit of piping on the adjacent wall, possibly pushed by high winds.

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Venus at Maximum Elongation

Today Venus will be at maximum eastern elongation, as high in the evening sky as it will appear for this current apparition. After today the planet will begin a slow slide back into the sunset, passing through inferior conjunction on August 15th and reappearing in the dawn during the first weeks of September.

Look for Venus to pass by the Beehive cluster around Jun 12th and have a close conjunction with Jupiter on a few evenings around Jun 30th.

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