Observing in Thailand


The telescope dome. Modern domes tend to be smaller than more old-fashioned domes for a given telescope size.
The telescope and the attached control building.

A few weeks ago I was at the Thai National Telescope (TNT). The telescope is pretty newly built (around 2012 I think) so everything is a bit more modern than most telescopes.  It’s a 2.5m telescope on top of Doi Inthanon, the tallest mountain in Thailand, about 2 hour’s drive from Chiang Mai. The telescope is run by a Thai government organisation called NARIT, who also run a handful of smaller (0.7m) telescopes around the world. 

The control room

We control the telescope and instruments from a spacious control room in the building attached to the telescope. The monitors here are for controlling and monitoring the telescope itself (on the left) and one of the instruments (the three monitors on the right). There was generally 2-3 telescope operators around, plus me (I was controlling just the camera). Also in the building is a mini kitchen, a bathroom, and a sofa people can nap on.

View from my window in the lodgeWe sleep in a lodge partway down the mountain. The lodge is in a holiday camp which is quite pretty, although it can be noisy when you’re trying to sleep during the day. It’s about half an hour’s drive up the mountain every afternoon and the same back down in the morning — an unpleasant drive when it’s dark and foggy, especially with the number of tourists who drive up the mountain to watch the sunrise. 

High humidity and rain

There was some awful weather and we didn’t get too much data — we were closed for 5 nights out of the 6 I was there. The bad weather is apparently related to the El Nino / La Nina weather cycle, where South-East Asia gets heavier rain during La Nina years.

I was here a year ago, and had much better luck with the weather then — and even managed to take some pictures of the sky when it was clear.

The TNT at night, taken a year ago

Observing at the INT

The INT viewed from the JKT
Telescope controls

The Isaac Newton Telescope is my new favourite telescope. Most telescopes the observer isn’t allowed to touch the controls for the telescope itself; we just control the instrument. At the INT you observe alone, meaning you control both. Driving the telescope is easier than I expected. For the most part it’s done from the command line — just type ‘gocat’ and the name of your star and the telescope moves itself to point to it. There are times though that you have to switch the telescope over to ‘engineering mode’, at which point you drive it with the big bank of switches on the right. There’s a window through which you can see into the telescope dome, and a microphone so you can hear the various parts moving. You also use the same buttons to open the dome up at the start of the night.

The telescope in access park

At the end of the night you have to bring the telescope into ‘access park’, ie move it so that the end of the telescope is reachable from the balcony. This is the most intimidating part of the experience, as you have to override some of the safety checks to bring it so low, meaning that a couple of alarms will start going off — you then watch the telescope moving towards the balcony pretty fast, while you manually silence the alarms. Once it’s parked you have to go up and refill the camera’s liquid nitrogen supply, to keep it cooled to -160 degrees. It only takes around 5 minutes, but when you’ve been working all night and want to go to bed that feels like a long time.


Inside the control room

Other than that the work is fairly easy; keeping an eye on the camera while it takes data. The control room is pretty cosy, with a coffee machine to keep you awake and a guitar to help you kill the time. You can wander off and explore the building if you want to, but do so at your own risk. The INT used to be the headquarters for the ING observatory, and much of the building is disused offices, meeting rooms, even a library. It’s a big building to be alone in all night, and you’d be surprised how much noise an empty building makes. Especially when you start to hear doors opening and closing…