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Fremont Peak and Glacier Point
Not sure if this is JD or one of the early SA writing this.  

 

 

The Astronomical Association of Northern California held two star parties this spring and early summer at Fremont

Peak State Park. Both were well attended with from one to two hundred people milling around the telescopes. On both

occasions the Sidewalk Astronomers set up their 24 incher under the watchful eyes of National Geographic photographer

Chris Springman who was assigned to get a picture for National Geographic's new book on Astronomy coming out in November.

 

There was also a total eclipse of the moon on May 24 for which we set up nearly a dozen telescopes in Golden Gate Park

which perhaps a thousand viewers used. It was an unusually dark eclipse and our shadow was so well centered on the moon

that for some time we could see that the redness all around the edge of the moon was brighter than it was near the center.

 

At the invitation of the "spelunkers" we took the 24 inch telescope to Frogtown on June 27 for the national

speliological convention. From there we went to Yosemite National Park on June 28 where we set it up at Glacier Point

for more than two weeks of public use. As usual the seeing there was excellent. The transparency was high, the turbulence

was low, and only one night was cloudy.

 

We went at the invitation of the park naturalists, and with a little help from our friends, the Yosemite Natural 

History Association. The naturalists made every effort to make our stay fruitful, and they succeeded like wild. They

made us very comfortable, supplied us with staff shirts, and brought up a screen from the Valley floor so that we could

give slide shows at the Point. This was probably the first time that astronomical slide shows have ever been given at

Glacier Point. It was certainly the first time that they have been used to help people understand the things which

they would see through a 24 inch telescope immediately afterwards. It was a good show.

 

Most days we operated telescopes from about ten in the morning till twelve at night. We were fortunate, this time,

to have a good sunspot for the first week and to have Venus as a crescent in the evening sky. Several thousand people

saw the sunspot through our little sun telescope (The Ugly Duckling), many thousand saw Venus, several hundred people

learned that they could see Venus in the daytime with their bare eyes, and several hundred saw the crescent moon on our

last two days. Some five hundred people, in all, attended the slide shows, and perhaps two thousand availed themselves

of the opportunity to look through the 24 incher (Delphinium). Unfortunately the slide shows could not begin till July the

2nd, when we got the screen, but the telescopes were used for sixteen nights.

 

As usual we tried to show samples of various sorts of objects through the telescopes. The Ring and Dumbell Nebulas

were used as examples of expanding gas clouds around old stars. N.G.C. 4565 and M51 (the Whirlpool) were used as examples of

edge-on and face-on galaxies. M22, M5, M3, and M13 were used as examples of globular clusters (nearly pure hydrogen, much

older than our sun). M7 and the Double cluster in Perseus were shown as Milky Way stars like our sun. We also showed

the Veil Nebula as an example of an exploded star. And we showed many clouds of gas and dust and stars in the Saggitarius

region, including the Swan Nebula which looks like a duck going over the falls. Albireo, a colored double star (blue &

gold), was usually shown on one of the smaller telescopes, as were the pair of galaxies M81 and 82. Late in the night we

usually showed M31 and its companion galaxies, and on one night, after almost everyone had gone, we saw the cluster of galaxies

in Corona Borealis. They are one and a quarter billion light years away. Imagine traveling at 186 thousand miles per

second for one and a quarter thousand million years!

 

Each evening a ranger gave a sunset talk at Glacier Point, then, on Tuesdays, Thursdays and Saturdays, after the

slide shows, he would give an astronomy talk down by the telescopes. Mostly they talked about constellations and did

a very good job. During the summer, the center of our galaxy is above the southern horizon in the evening sky, and one of

the things which we usually do is to ask the viewers to compare the edge-on galaxy NGC 4565 with our own galaxy seen

edge-on through the summer Milky Way.

 

On the last weekend Doug Berger was there and showed us where to find the new comet which he had discovered on the

4th and 5th of July. It was just below (east) of the diamond in the Dolphin and filled the whole eyepiece field in Delphinium.

Then, on Saturday, July 12, the night before our last, someone saw a satellite in the handle of the Dipper, and,

since there were some viewers still with us, we put the 9 incher (Tumbleweed) on the satellite. What a shock: It  

looked like a whole caravan of objects, many in front and many more behind. It stretched out several eyepiece fields

long, even in the 9 incher at 45 power. There was only one very bright one in the middle of the caravan, and when it

went midway between M81 and 82 as seen in Tumbleweed we swung Delphinium around. What a show! We counted more than

thirty pieces in front of the main body and probably could have counted more behind (following). The lateral displacement

of the bits was probably a few percent of the displacement in the direction of travel (which was probably several

degrees). Many of the bits were flashing as if tumbling at different speeds. It was again a good show.

 

The morning after our return we received in the mail a newspaper article from someone who was with us that night

saying that a U.S. mapping satellite, Pageos, orbited in 1966, had been hit by a meteorite on Saturday and was drifting

in 27 pieces. 27 yet!

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