Wednesday, August 15, 2007

GMRT, India 8/11/07-8/15/07

I appreciated the drive north from Pune to the telescope more this time than last, because I actually had an idea of where we were going, and I could pick out familiar landmarks as we got close to the GMRT: the first visible antenna on the west arm, still 45 minutes from the telescope; Narayan Godt, a prominent hill a few km west of the GMRT, topped by a small temple and with some really interesting geology (I carried a couple rocks home last time); the Indago winebar/restaurant on the road to Narayangaon; signs in Hindi I could not read; etc.

I finally arrived around 8:45 am, checked in, bought food coupons for the canteen, and feasted on an alu paratha and chai. Soooo gooood! The first day was pretty boring, but that evening during dinner, we lost our internet connection. This had several significant repercussions (1) I had to be a bit more creative in how to entertain myself the next couple days (I'd only printed out so many journal articles to read in advance), (2) but more importantly, it meant I had to get a hold of Laura Chomiuk before her observations because I was there early for my observations, in order to do hers and I had been planning on copying her observing command file and target list that evening. . So, without a command file and target list, 2 phone calls, 20 minutes and 129 rupees later, I had everything I needed to regenerate her files. It was not as dramatic as it sounds, because despite the network being down, the GMRT's internal pages were still accessible, just inconvenient.

The next day, while starting Laura's observations, I learned that five of the six antennas on the west arm of the array were down—1/6th of the array! So, as an introduction to the GMRT—it consists of thirty 45 meter dishes. Ten of these make up the "central square", and the last twenty are arranged in a "Y" shape similar to the VLA. They were built very quickly and incredibly cheaply. I find this an amusing description: "The design is based on what is being called the `SMART' concept - for Stretch Mesh Attached to Rope Trusses." That is, they are not solid dishes, but made of wire mesh. The electronics do not use cryogenics. In fact, the dishes themselves were lifted and leveraged onto their pedestals by large pulleys and teams of men pulling on ropes—none of this high tech stuff. Further, it is a unique instrument because the receivers are sensitive to really low frequencies: 150-1420 MHz. But, as a result of their design, they also suffer from a lot of Radio Frequency Interference (RFI) that makes reducing data a challenge at times. Anyway, it turns out that the optical fiber that carries the signal from the antennas along the west arm and the internet that comes from Narayangaon are one and the same. In the theory that they'd repair the telescope in all haste, this was good news for our internet connection. However, we further learned that the optical fiber had in fact been cut by road workmen in three places (Sabotaged!), and would have to be spliced together The earliest prediction for a return to normalcy was Tuesday night.

In the meantime I have been doing other astronomy, running Laura's observations, taking the usual three tea breaks a day, and running around the GMRT in the afternoons. There is a nice ~2 mile dirt road loop around the antennas in the central square. Running a couple laps in the afternoon keeps me productive in front of the computer the rest of the time. It was a fairly regular thing, that is, until I was informed of the recent cheetah sighting. (Leopard!) At which point I was strongly encouraged to not become leopard bait. Apparently cheetahs do exist in very few numbers in India, but they are nearly extinct, and it is common for the locals to get cheetahs and leopards mixed up (bah—english!). The next day, I was feeling rather antsy just sitting around, so I risked freaking out the locals instead of forgoing the run altogether. I ran north along the road, outside of GMRT property with the theory that a leopard would be less likely to wander near the road and, as Emily Freeland later pointed out, if it did there would be more people around to help me. Even in the middle of nowhere (like the GMRT), India is relatively densely populated, so I saw many people, especially women working in the fields, a couple men driving cattle, and many bikes, motorcycles and cars on the road. There are a lot of crops that grow in this area, but the major cash crop is sugar cane—also a perfect place for a leopard to hide because it grows tall and dense. Anyway, I survived my run down the street, with only being stared at by ~40% of the locals as I went by: a white girl running down the street in shorts and a t-shirt in rural India might be the only thing they see less frequently than a cheetah.

The following day I took off from running, and went for a stroll around the GMRT site; I found out the leopard had actually been sighted more than three weeks ago, and it was south of both the GMRT and the nearby village of Khodad. However, I did see a herd of cattle wandering through the woods/brush; the GMRT site used to be fallow farming land, but has since been extensively reforested. And, although I only learned about it later, I got a friendly wave from some of the tribal people that were herding them! At the time I saw them drinking from a water spout near on of the antennas—I couldn't imagine they were doing any repairs, because they were dressed far differently than anyone I'd seen around here, but the east arm of the array was now down along with the west, so who knew.

So, today was Independence Day. There was a flag raising ceremony in the morning in front of the building, and there were special sweets later in the day. Unfortunately, it is nothing as elaborate as Republic Day in January (more on that in a later email). The antenna is completely up and running again because the workers were up until 1 am last night splicing fiber, but it took half of today before the internet was working again. Aside from trekking, and reducing data (my own of which I don't have yet), there's not much to do around here.

Hope you all are well, and I will try to make up for my complete lack of India reports last January by writing more later this week.

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