Thursday, December 19, 2013

Controlling the world's largest telescope with a Nexus 7

it's 5:30 in the morning, and I'm playing with my tablet. But this isn't a Candy Crush all-nighter, or even a Minecraft marathon. This is work - I'm using the tablet to observe. Via a combination of free apps from the Google Play store, I've taken control of the biggest telescope in the world, the Arecibo 305-m.
Remote observing allows observers to connect to the telescope from anywhere in the world (if they have an internet connection). People use Linux boxes, Macs, Windows PCs and, nowadays, tablets. I'm using a +Nexus 7, its high-resolution screen making it ideal for this sort of task.
To connect to the telescope, I'm using two pieces of software - an SSH  client and a VNC viewer. The first of these isn't, strictly speaking, necessary. I use it only to log in to the Arecibo Linux network and start up a VNC server, something I could do from a different computer at an earlier time. However, computers crash and there's no absolute guarantee that a VNC session started earlier will still be running, so I like to have the SSH client to hand. I use JuiceSSH, which is simple and does everything I need it to do.
The second app, the VNC client, is absolutely essential. By connecting to a VNC session running on the Arecibo system, it transforms the tablet into a remote terminal that can do (almost) anything I could do from the control room. I use the bVNC app, which supports SSH tunnelling in its free version, allowing me to connect through the gateway machine to a computer in the control room.
Once I'm in, the operator turns over control of the telescope to me, and I'm away. I can tap a source on the graphical display and bring up its information, then hit another button to send the telescope to point at that source. I can tweak the settings for the observations, or even change to a completely different observing mode. I can call up monitoring software and watch the data flow in, or even run a quick data reduction script to see if I've found anything.

This is all great fun, right up to the point where the operator says "time's up" and I have to hand the telescope over to the next user. And to think - I can do all this from the comfort of my armchair, with a computer I can hold in the palm of my hand!

Monday, December 9, 2013

When the network became a notwork

"When sorrows come, they come not single spies but in batallions" has certainly felt true over the last week. Firstly there were problems with the car, next with the wireless router, and finally with the wifi on the PC.
On Wednesday evening the car suddenly started making a metallic grinding noise. This was tracked down to the vicinity of the front driver's-side wheel. Being not much of a mechanic myself, I diagnosed this as needing to be taken to someone who was. Ideas included a problem with the brakes and a problem with the wheel bearing (all too common with Puerto Rican roads, alas).
So on Thursday morning I drove rather gingerly down the road to our local garage and dropped the car off. The mechanic didn't know whether he'd get a chance to look at it that day or not, but as I wasn't about to drive the car anywhere until it was fixed I left it there and walked home (about 5 minutes up the road).
I was able to get lifts in and out of work on Thursday and Friday, although this meant that I got home about 3:30 on Friday, intending to do more work at home. Unfortunately, we had (apparently) no internet connection. This isn't that uncommon an occurance, so I phoned up my ISP to find out what was happening. They told me there were no problems at their end, and that they could see my router. This was a bit unusual, so I tried plugging the PC straight into the modem. We had internet - but the router couldn't see it!
At this point I switched tasks, as 5pm was approaching, and walked back down to the garage to check on the status of our car. This turned out to be 'mysterious' - the noise had been there on Thursday when they had moved the car around, but had vanished by Friday when they had had time to look at it. They had checked the brakes, wheel bearing, gearbox, etc. and all were fine, so they said to bring the car back if it started making the noise again. They also said - and this is one of the bonuses of being in Puerto Rico - that they hadn't fixed anything, so there was no charge for the time spent looking for the problem!
So, back home and back to working on the router. Following instructions on Belkin's website, I tried resetting the router and running the setup utility, and (when that failed to improve matters) gave them a call. It turned out that the router was still under warranty, if it was a hardware problem, but that my free over-the-phone support had expired so if it was software I would have to re-instate this, at a cost. It did, of course, turn out to be software, so I gritted my teeth and gave them my credit card number. That's when things turned surreal...
The support lady came back to me to say that they couldn't process a card with a Puerto Rican address, as it wasn't in their system. They could take cards from the US or Canada, but not US territories, so she couldn't tell me how to fix the router! She even checked with her supervisor, but 'the system' was king, and there was no way for me to give them my money, so I said goodbye and decided to do some poking myself.
I started by plugging the PC back into the modem. Nothing - the internet had gone down at the ISPs end while I had been on the phone. Fortunately it came back rather quickly, which enabled me to discover that the hive-mind of the internet has very little useful to say on how to fix faulty routers. With a bit of poking around in the settings, I was able to get the router to pass on the connection wirelessly using 'Access Point' mode (which didn't require an IP address for the router). The downside of this was that none of the router functions were available, so I only had the single IP provided by the ISP and (for some reason) I could only access this from the PC, not from the tablet. At this point I gave up and went to bed for the night.
The next morning, the wifi on the PC had stopped working. There was a wifi signal coming from the router, but the PC could no longer see it (the tablet could, but it couldn't get an IP address from the ISP). Time for a trip to Office Max! There we found a USB wifi aerial, and also spotted a wireless router that actually cost less than Belkin's telephone support. It was only single-band, while the older router was dual-band, but we had only ever used the s-band wifi as the c-band signal doesn't pass through our walls, so no real loss there.
Back home, the new router and the USB aerial were easy to install (although the PC is now perilously short of USB ports), and we finally had a network instead of a notwork!
Codicil: I celebrated having the internet back by tweeting "Back online with a new router. Won't be buying @belkin again, at least not until they can give customer service to Puerto Rico!" This led to a reply from @BelkinCares: "Hi Robert, allow us to assist you. What is your #Belkin product?" I've been trying a few things with them - so far the only thing they got me to do that I hadn't already tried was running the setup from the CD (which I had forgotten I had). Unfortunately this turned out to be identical to the setup I had run from the PC before, so I haven't yet got two working wireless routers...

Sunday, December 1, 2013

Exercise - why bother?

It seems that the HR department up at USRA would like us to take more exercise. At least, that's what they keep telling us. They even have events to encourage people to exercise, such as walking competitions and the 'New York minute'. However, I haven't felt inspired to take part in any of these.
Leaving aside the somewhat dubious science behind some of the 'healthy living' advice in the 'New York minute', and the off-putting name (can anything associated with New York be good for you?), there was the chance to win an iPad mini - surely motivation enough? Alas, no. You had to reach a certain number of 'points' to go into the draw. Like the earlier walking competition, this meant that if you weren't already exercising a lot and following their (pseudo-scientific) idea of a healthy lifestyle, there wasn't much chance of winning anything. Rather than encouraging exercise, the competitions reward the already-fit and discourage those who are ostensibly being targetted.
Yet last week I took part in the Observatory's Thanksgiving 'Turkeython'. This event had no significant prizes - not an iPad in sight - but it was fun and social. This was exercise and team-building done right. I had a good time even though, like last time I entered, I ended up limping.
Maybe fun is a better motivator than iPads and competition! 
(Photo by Tony Acevedo)