Monday, May 18, 2009

I just sent this off in an e-mail, and thought it would make a good weblog post too:

I have to admit that I've been using the school observatory for a relatively short time, so it's not in great shape and I'm not totally plugged into "the scene" here in Shanghai. But I'm happy to share what I know, which I will summarize in a few paragraphs.

Shanghai today is NOT a good place to do astronomy. The earliest astronomers in Shanghai were the the Jesuits, who had an observatory by the St. Ignatius Cathedral in Xujiahui. Light pollution must have been a problem for them back then because they built a second observatory out on Sheshan (I'm not a historian; all this stuff is Google-able). When the local Chinese took over, they used the Shanghai location to build the offices of the Shanghai Astronomical Observatory, which includes an actual observatory, but they do all the serious work out in Sheshan. Even Sheshan is not far away enough to avoid the effects of the city lights, though; I hear it's being slowly phased out and a new observatory being built in Zhejiang to replace it. China is in a period of heavy telescope construction right now, with big telescopes just built or in planning for Beijing, Yunnan and Guizhou.

My school has an observatory, one of a few schools in the area to have one. It's the only international school that has one as far as I know. It's not big, a 220mm Cassegrain reflector, F13 or so. It's equipped to look at the sun, works at night for objects visible in the city sky, and came with a CCD camera for imaging faint objects (I haven't gotten it to work yet, though). Like I said, light pollution is horrible in Shanghai, giving the sky a tint of background light that washes out most interesting objects. Look at the Pearl Tower from Puxi on a smoggy day, and then imagine what would it would look like if it were hundreds of light years away. Zhangjiang High-Tech Park is particularly bad because it has lots of factories that work around the clock and keep floodlights on at the factory campuses.

Even though light pollution is bad, this doesn't meant that all hope is lost. There are still many things in the sky worth looking at. In the city, the best thing targets for observing are the Moon, the planets, the sun (if you have the right equipment!), the Int'l Space Station (ISS), and Iridium flares. The moon is great even just through binoculars. As it grows and shrinks, the terminator line between light and dark is the best place to view shadows from craters and other features. Planets come and go on the order of months, so they're good targets if you want to take things slow. Lately Saturn and its rings have been dominating the late night sky. The rings are slowly angling so that they'll be pointing directly at us and almost invisible in September, so catch them while you can. Venus is easy to see in the morning and evenings, lately favoring the morning. With the correct, quality equipment ("arc welder's glass"), it's possible to get a look at the surface of the sun during the daytime and hunt for sunspots. The Sun has been very quiet lately with zero sunspots, but we're supposed to be coming up to a maximum in 2012 (Mayan armageddon and all that) so it's worth keeping an eye on. The ISS and Iridium communication satellites are fun to look for; when they make certain angles to the sun they can look like very bright stars moving across the sky. The good thing about them is that their routes are predictable, so various websites will provide reliable forecasts of ISS passes and Iridium flare sightings. (I list some below.)

I've be happy to host you at the school's observatory, both day or night. As long as the weather is clear, I'm pretty sure there will be something worth looking at. Also, it'd be worth talking/researching a bit what telescopes/binoculars are best for city viewing.

If you're doing an astronomy article, it's almost a MUST to mention the eclipse coming up this July. I think it'd be worth making a daytrip out to Nanhui or farther to get the full effect.

Here are websites that I recommend for Shanghai astronomers: (weather; main site also has e-mail reminders for Iridium flares, ISS) (maps of the sky) (space "news") (Shanghai astronomy BBS; Chinese) (Adam Minter on the Jesuit observatory) (SH Astro Observatory site)