78 people. Last night was prime time for the Perseid Meteor Shower. Actually, the best of the shower was due to arrive around 3-4 AM when yours truly was in his beddy bye. And after the Moon (89%) arose, even the early meteors were largely invisible. None the less we got to see quite a few fine streaks. Nothing like the 15 minute monster we saw during one of the Leonid showers but fine all the same. Quite a few folks brought lawn chairs and spent a good deal of the night looking for the meteors. We also saw several satellites passing in polar orbits. One lady asked to see the satellite when she came out of the Observatory where Nick was holding the fort. She was surprised when I told her that it had passed out of view several minutes before. Most things in the sky stay put for a relatively long time but you have to be quick for meteors and satellites.
Early in the evening we could see a lot of detail in the Milky Way. I was able to point out the Sagittarius Arm, explaining that it was one of the wheeling arms that are like the prominent arms in the Whirlpool Galaxy. It was quite obvious although foreshortened by our perspective. The Milky Way all but disappeared when the Moon rose shortly after 9:15 PM.
Our first target of the evening, Jupiter presented some problems between 8 and 9 PM. One patch of clouds in an otherwise clear sky kept hiding Jupiter just when the majority of people arrived. Finally, Nick and I gave up and we watched Alcor/Mizar until the clouds blew out to sea.
We went to the Moon several times throughout the night as new groups of people came. I am not a great fan of looking at the Moon when it is nearly full. The surface has few shadows and the contrast is low. When it first came up, I projected its image on the dome. It was just coming over some trees, and we could clearly see the shadows of leaves waving in the wind on the projection.
We looked at some summer favorites which are bright enough to see well. This included M22 (globular cluster in Sagittarius), M8 (a diffuse nebula called the Lagoon), M31 (the Great Andromeda Galaxy), the double cluster in Perseus (NGC 869) and a small planetary nebula IC 1747 next to Epsilon Cassiopeia. They were quite good for a night where we had an 89% Full Moon.
It grew quite chilly last night. I was glad that my wife told me to get the fall jacket out because by midnight the temperature was 57. Quite a change from two weeks ago.
Huge Mars Approaches the Earth.... NOT!
The so called Mars Hoax is circulating again across the web. I have had people ask me what we are planning for the great encounter this month between Mars and Earth at the Observatory and by email. Simply put we are not doing anything because nothing is happening.
The Mars Hoax evolved out of the very real close opposition between Earth and Mars on the night of August 27, 2003. An opposition occurs when an outer planet is overtaken by the Earth. Newspapers and television broadcasts at the time pointed out that Mars would be unusually bright and historically close to the Earth. Several commentators stated that Mars would outshine the Moon that night. Weirdly enough, this was sort of true but only because it just happened that August 27, 2003 was the night of the New Moon. This odd factoid got misrepresented as Mars will be much bigger than the Moon on that night.
Since 2003, every August, a number of reports show up on the internet saying that on the night of August 27th, Mars will be bigger than the Moon and much brighter. This simply isn't so. Earth passes Mars (technically called an opposition) roughly 780 days give or take a couple of weeks. This means that an opposition occurs approximately every two year but two months later in the year. Years in between have no opposition at all. Due to the shape of the orbits, oppositions which occur in the late summer are closer and brighter than oppositions that occur at other times of the year. The opposition which followed the close opposition in 2003 was in early November in 2005 and the next opposition after that will be in late December 2007.
We will not have an opposition of Earth with Mars at all this year. In 2006 during August, Mars is very low in the western sky at dusk setting roughly an hour after the Sun. Effectively it is too close to the Sun for safe viewing. It is nowhere near a close opposition. In fact, it is almost completely on the far side of the solar system and quite small and dim.
Along these same lines, a number of infrequent visitors to the Observatory were disappointed when I told them that they could not see several planets and constellations which they had promised their kids they would see. Much as I would have liked to be able to show Saturn (or Venus or Mercury) to these folks, I couldn't because they are all clustered near the Sun in the morning twilight. Similarly, I couldn't show folks Orion, however spectacular M42 and M43 may be. They are winter constellations. I think all of this is indicative of our loss of Nature. We used to live in Nature and were intimately aware of its comings and goings. We ate whatever foods were coming to harvest or made do with preserves. One person talked about changing the laws of physics which she considered inconvenient the way you would change an out of date legal concept. In spite of all of our ability to control aspects of Nature, we are still very much at her mercy. This is true in the small world of not being ab Celestial object in the wrong season and even more significantly when Nature goes on a rampage and sends Katrina our way.