On the road again...

Yesterday evening I got home from the teacher continuing education workshop at McDonald Observatory, and today I am at the airport, ready to fly to Hawaii to use the Keck telescopes. It will be a fun trip, but I'll be ready to come home.

Travel Excitement

Yesterday, I left the summer meeting of the American Astronomical Society behind to come home. The meeting is still going on through tomorrow, but I finished my contribution on Monday and had work to catch up on at home. My intent was to get home in the mid-afternoon, catch up on the Tuesday news from the meeting, and then write a little blurb on that. But my airline (which shall remain nameless to protect the guilty, but let's pretend it was called "Shamerican") had other plans. My flight was supposed to leave Saint Louis at 2:05pm, which came and went uneventfully, meaning I was sitting in the gate area not hearing a peep. First we were told that the plane was being clean (which I believed, since it arrived late), but after twenty minutes, I stopped believing that. I've never been on a plane that clean. At 2:20pm, we got word that maintenance was still working on the plane, and that we'd be boarding no later than 2:45. At 2:45, we were told that maintenance was about done. In the meantime, I was called to the desk and given a new seat because my original seat (an emergency exit seat) was broken. So I assumed that the mechanical problems had to do with the seat, and that they'd decided they couldn't fix it. Wrong.

Finally, at about 3pm, we boarded. It was one of the regional jets operated by Shamerican's partner, Shamerican Shconnection, so it didn't take long to board. It was hot in the airplane, though, because the A/C was off. I assumed it would get cold once the engines were on, as this has happened to me many times before. We pushed off from the gate and took off.

Shortly after takeoff, I suspected something wasn't right, because my ears were popping much more than normal. But these partner airlines often seem to have trouble getting the airplane pressure dialed in, so I figured they'd get it right and all would be well. Wrong again.

We turned to the south to head to Austin and levelled off at 5,000 feet or so (again, common until air traffic control says we can go up to the cruising altitude). But we didn't go up, and then we turned back to the east. And the pilot came on, apologized, and said the cabin was unpressurized, and we had to go back to St. Louis and get it fixed. He hoped that the maintenance had just forgotten to connect some hose after their earlier work.

I wasn't worried at this point. The plane was flying just fine, and we were at a low enough altitude that the unpressurized cabin was not dangerous. We had to dive down to the runway, but we landed fine and taxied to a new gate. (Meanwhile, the A/C was still not working, and it was really hot and stuffy on the plane.)

After we were at the gate 15 minutes or so, we were told that they couldn't fix it right away, and we had to get off. The pilot ominously said to stay in the gate area, and that they hadn't cancelled our flight "yet."

Thankfully, at this point, the story improves. The airline gave us a different plane, and we all boarded and took off for Austin at about 5pm (only one hour after we were already supposed to be back). Two hours later, we were in Austin, where we had to wait 15 minutes for our gate to clear. No matter that the neighboring gate was open with no incoming flight. Whatever. We were happy to be back safely.

Our pilots, flight attendant, and the in-airport gate crews at St. Louis were all very polite and helpful, and I know these problems weren't their fault. I am a little miffed that the maintenance had been working on the plane and didn't get it right. I'm more miffed that I know that I won't get a word of apology from the airline. I know these things happen, I know we were never in mortal danger, and I know that I got home eventually. I can accept that. But rather than forcing the pilot and gate crew to give out apologies for things that are not their personal fault, I'd like an apology from the party with the ultimate responsibility, the airline. Southwest Airlines follows up incidents like ours with personal, written apologies.

I don't care about getting some additional compensation or free food or extra frequent flier miles. I would just like some admission from the larger corporation that we, the customers, mean more to them than just dollar signs. At a time when the airline business is suffering, such an acknowledgement might make me more amenable to their situation and more willing to put up with increased fares or inane new charges like bag-checking fees. But the deafening silence the customers get from the truly responsible party (the airline, not their employees who have no fault in the issue) when problems arise makes me less happy to put up with their shenanigans.

I'm not asking an airline to cater to my every whim or to offer unreasonable compensation levels. A simple, honest "we know this happened, it shouldn't have, and we're working to keep it from happening again" would be enough. Yet I know I won't get it, though I will be asked to fork out even more cash for even worse service in the future. And that angers me.

Meet me in St. Louis...

Greetings from Saint Louis, Missouri! This week is the summer meeting of the American Astronomical Society, the smaller of our two annual meetings. Astronomers from around the country have descended on St. Louis in order to discuss our latest research, reconnect with old friends, and hopefully meet some new people.

This week's meeting also includes members of the Astronomical Society of the Pacific, a collection of both professional and amateur astronomers. Much of the summer meeting is dedicated to planning and discussion about next year. Why? 2009 has been designated as the International Year of Astronomy, and so many special events are being planned to celebrate the 400th anniversary of Galileo's first astronomical use of the telescope, which we will use as a reason to promote space science to the general public.

My stay here will be short. I have a presentation this afternoon, and I'll be heading home tomorrow. The meeting continues through Thursday. So, you can expect to see some press releases about new and interesting research coming out of St. Louis this week! I'll try and bring you what inside information I can.

traveling and telescopes

Last week American Airlines had to cancel a couple thousand flights due to mechanical issues. Many people who were supposed to fly (like me) ended up staying home. I personally know people who missed out on weddings and important meetings because of all of the chaos. Airlines can be sorry all they want, but when people miss events like weddings and funerals, there's no way to apologize properly.

Anyway, what happens to astronomers who miss a flight to a telescope? Telescope time is a rare commodity for many astronomers. A few nights a year at a large telescope is enough to keep most observers gainfully employed. Telescope nights are typically scheduled 6 months in advance, and there is almost no flexibility in the schedules of most telescopes. So, what happens if you can't get there?

For most telescopes, the astronomer is out of luck. Often the astronomer is solely responsible for the telescope; if there is a telescope operator, that person is quite knowledgeable about the telescope and the mechanics, but would not be able (or willing) to do an astronomer's observations for her. For that reason, many astronomers (myself included) travel a day or more early to the telescope. The extra night can be used to settle in and to start to get on a night schedule.

I've had to use that extra day several times, especially when I fly to South America. If I miss my connection, or the intercontinental flight is delayed for 12 hours (which happens quite a bit!), there is no option -- I'm going to arrive 24 hours later. It is awful to hop off of a 7000 mile plane trip and then stay up all night, but some times it has to be done.

In some cases, observatories are set up for "remote observing," where the astronomer can be thousands of miles away and observe over the internet. This runs risks, such as the internet going down, but some people prefer that risk to travel, and sometimes it can't be helped.

After the terrorist attacks of September 11, 2001, all air traffic was stopped for several days. At least one astronomer in California had time on the Keck telescopes in Hawaii, but obviously wasn't able to get there. So, he drove from Pasadena up to Santa Cruz, where there was a room that was set up with all kinds of cameras and computers for observing, and he was able to use the telescope quite successfully.

But few observatories offer remote observing. It is expensive and time-intensive to set up (although it can pay for itself in very little time), and it brings new technical challenges. How can astronomers know they are getting high-quality data, if those data will take hours to transmit across even the fastest internet? Without the ability to step outside, how can the astronomer know what the weather (specifically cloud cover) is like? And are the telescope operators willing to take the extra training they would need to troubleshoot bad internet and other issues that the astronomer would normally take care of? These problems are more difficult than they sound, but they are not impossible to solve. The number of telescopes with remote operations capabilities continues to grow, albeit slowly.

For telescopes withot remote operations, however, not arriving at the telescope means no data. Sometimes you may have a friend you can call to do you a big favor ("Hey Bob, you weren't doing anything tonight anyway. How about staying up and taking data for me?") It's a chance we take, just like the chance with the weather. Often you can request new time at the telescope, and the committees that assign time will take bad weather or travel problems into account (provided that the problem is severe -- missing several nights because of poor planning does not endear one to these committees). But there is no guarantee that you will ever get that telescope time again -- maybe someone else will do the project first at another telescope, or maybe the science you propose to do loses its luster. And, often you have to wait an entire year for more telescope time, because most stars are only visible at certain times of the year.

So, when an airline grounds over half of its fleet, astronomers can be in quite a pickle, too. Like everyone else, we wring our hands, blow steam out of our ears, and deal with the consequences.

Super-Asymptotic Giant Branch Stars

As I promised in my last post, here's an attempt to explain why in the world I would travel to London for a one-day visit. The challenge is to see if I can both explain the science and keep this post reasonably short.

First, we need to talk briefly about how stars work. Stars shine by nuclear fusion. They spend most of their lives turning hydrogen into helium. But eventually the hydrogen fuel runs low, and the star starts to burn helium into carbon. Almost all stars bigger than half the sun's mass go this far.

For stars up to about 7 times the mass of the sun, this is as far as the star gets. Once it has burned all of its helium, it ends its life, throwing off its outer layers as a planetary nebula and leaving behind a glowing lump of carbon ash called a white dwarf.

For stars more massive than about 10 times the sun's mass, the star is big enough to start fusing the carbon into oxygen, neon and magnesium, which then ignites and fuses into silicon and related elements, which then fuse to make iron and nickel and related atoms. And then the star explodes as a supernova star, spewing most of these elements out into the universe.

My story above, though, has a bit of a hole in it. I said that stars smaller than 7 times the mass of the sun make carbon white dwarfs, and stars bigger than 10 times the mass of the sun explode after fusing elements up to iron. But what happens to stars that are 8 or 9 times the mass of the sun? These stars are big enough to burn carbon into oxygen, neon and magnesium, but they are not big enough to fuse these elements into silicon and iron.

From the standpoint of theory, it is possible to make a white dwarf out of oxygen, neon and magnesium. It is also possible to have oxygen, neon and magnesium explode in a special kind of supernova explosion. But we don't know which of these scenarios happen.

Our meeting in London was therefore to discuss these stars. We talked about what we know about these stars between 7 and 10 times the mass of the sun, and what we don't know about these stars. Frankly, there are a lot of mysteries, and not a lot of answers. What happens to these stars depends a lot on how fast the stars are rotating, how quickly they are shedding their outer layers, and how much the inside of the star is mixed up by the slow boiling that happens inside many stars. But these mysteries are what makes the science interesting, and will keep me working for years to come!

I talked about the white dwarfs I have been studying, and a British group talked about their studies of the types of stars that explode as supernovae. If we combine our two areas of study, it seems that these stars must explode and not make white dwarfs. But there is a lot of careful study we need to do before blindly combining our work! I may make different assumptions than the other group which can affect the outcome of our data, or maybe one or both of us have made mistakes in our analysis. Only time will tell!