Sunday, May 30, 2010

Waco Star Party announcement

Here's something my local club is doing:


June 5th, 2010
8:40pm to 10:30pm

The Central Texas Astronomical Society (CTAS) will have our Waco Star Party for members and the public on Saturday June 5th starting at 8:40pm, regardless of weather. We will meet as usual at the Waco Wetlands. Bring your telescope (if you just got a telescope and want help with it, this is a great place for that) or just enjoy those of the members as we explore the night sky of June.

We will begin with an indoor program on the life-cycle of stars, even if it's cloudy.

Then, weather-permitting, we hope to see objects both inside our Solar System, elsewhere in and around our Milky Way Galaxy, and outside our galaxy. In our Solar System, we will look at Mars and Saturn. Elsewhere in our galaxy, we would like to look at the Beehive open cluster of stars (M44) which can be seen with the naked eye as a faint glow, the Hercules globular cluster (M13) which is a ball of older stars that orbits our galaxy, and a nebula that is the remains of a burnt-out star (M97). Outside our galaxy, we will look at the Leo Triplet of galaxies, a trio of three galaxies that can be seen in one telescope field of view, and the Whirlpool Galaxy (M51)--a cannibal that is eating up a neighboring galaxy which can also be seen.

Experience it yourself and work with other local amateur astronomers to explore all that the night sky has to offer. This event is free to the public and is sponsored by CTAS.

Directions to observing site:
Lake Waco Wetlands at 1752 Eichelberger Crossing Road.

Directions: From Interstate 35 take the Exit 330 and proceed west (toward Meridian) on Hwy. 6/Loop 340. Continue for approximately ten miles to the intersection of Hwy 6 & FM 185. Turn right onto FM 185 and continue 0.6 miles then turn left on Eichelberger Crossing Road. The Lake Waco Wetlands Research and Education Center will be 1.6 miles on your right at 1752 Eichelberger Crossing Road.


  1. Sounds fun. Hopefully the public will take advantage of this opportunity. I'm going to start looking for a local club that will do things like the that.

    Hey, Alex, I have a question that I couldn't find any definitive answer to out on the Web. Looking at the moon can't cause eye damage, correct? All I read is it can be uncomfortable, depending on the moon's brightness and your eyes sensitivity, but not that it can damage your eyes, like looking at the sun can cause.

    I've been staring at it quite a bit, trying to learn all the geological features.

  2. No worries! This is kind of surprising, but the way optics works, with optics, you can't concentrate light in such a way as to get a greater intensity than you would have at the source (but you could put in a camera and collect light over time, and then get a greater intensity). So, in particular, you can't get a greater intensity of light through a telescope pointed at the moon than you would get if you stood on the moon and looked at the ground. Now, the moon is made of light grey rock. So the brightest you can make the moon in a telescope, no matter the size, is what light grey rock looks like on a sunny day. And that won't blind you. So the worst effect you can have would be if you were on the moon and crawled out of a dark cave on a sunny day (actually, every day on the moon is sunny, since there is no atmosphere) and looked at the ground. You'd be dazzled for a while, but that's all.

    The reason the moon looks so bright in a telescope is (a) the contrast to the darkness around it, and (b) the dark adaptation of your eyes. Absolutely speaking, the moon is no brighter at night than during the day. And it's not that bright during the day!

    One piece of advice I heard for lunar observing is to sit on a lit-up porch. This is convenient for consulting printed moon maps ( if you have a color printer, you can print the ones at ), and the moon doesn't dazzle as much.

    I don't like using filters on the moon to reduce brightness, as they reduce sharpness. The best way to reduce brightness is just to increase magnification which thins out the light (or something like that).

    The sun is a different matter. You can damage eyes by looking at it without a telescope, and if you stood on its surface, you'd go blind even if you didn't vaporize. Unless we get a nuclear war in space, the only object in space dangerous to look at through a telescope will be the sun. (Theoretically, one could make a gigantic telescope and looking at other stars would be dangerous. But the telescope would, I think, have to be bigger than the solar system (I haven't done the math). Certainly nothing we're going to make in the next couple of decades!)

  3. That's a relief. Looking at the moon doesn't bother me. My brother, on the other hand, with his light blue eyes, can be too much for him.

    I don't know the terminology, but the cover that goes on the end of the telescope has a cap in the middle that you can take off while still having the cover on, and I think that helps decrease the light that the telescope captures.

    Thanks for the tips. I'll print out one of the moon maps.

  4. I also like Sky and Telescope's Field Map to the Moon (available from amazon).

    Yes, the cap will reduce brightness, but it'll also reduce detail. I such a cap with an off-center 4.9" hole for my 13" scope. It made moon images look better aesthetically, but decreased detail. It made Mars look better and increased detail. But that's with a 13". With a smaller scope, I don't recommend decreasing the aperture.