I was visited by a man (forgot his name) and his 2 sons. He joined the RASC TC last summer. He brought his small refractor on alt-azimuth mount and metal tripod. I encouraged them to set it up.
John arrived with a Skywatcher 8" f/6 Dobsonian.
Gilles and his wife (have also forgotten her name; Nicole!) arrived with their computer-controlled Meade ETX-90 Maksutov-Cassegrain.
§
I wanted to arrive really early. I wanted a relaxed time frame to set up. I did not want to be rushed and still assembling as people arrived. The first DDO tour was scheduled to start at 8:30 PM.
I left my house at 7:00 PM. The traffic on the Lakeshore was heavy which immediately slowed me down. I made a last-minute decision to transfer from the Lakeshore to the Gardiner at Dufferin which proved wise. It gradually sped up the rest of the way. The DVP was surprisingly smooth running.
When I arrived the DDO at a little before 8 I found the gate locked! I panicked: did I get the dates wrong? There were a couple of students working on the lawn. As I pulled my mobile phone out to call... someone... Ian S drove up. He asked if I had a reservation. I explained I was here to help. "Oh good!" he said, "Not everyone went to Starfest."
It was a good timing. I set up at a leisurely pace as some of the first visitors milled in.
§
I took a lot of my new gear up to the DDO...
My new folding picnic table was very handy. I used it for the red LED light box. I sat at it several times to make notes, look up things. Some of the DDO visitors also sat at it. Gilles and his wife particularly liked it. They also have a folding wood TV table which they often find too small.
Speaking of the light box, I had re-engineered it again (is this version 3.0 or 4.0?!). One of the (cheap) push-button switches had failed due to some collisions or pressure on the connectors. I had replaced it earlier in the day. I had wanted to test the white GE plastic sheet as a diffuser and the clear sheet as a cover. In order to place these sheets over the LED array, I had to remove the array from the box surround. To elevate the diffuser above the array an appropriate distance, I cut some short pieces from a clear juice bottle. They held the diffuser about 15mm above the LEDs. Overall, this is a good working solution! Mel liked it too. "I've never seen anything like that before." It looks like I have this all nailed down...
The "big DOC" was useful again. Not only for myself but my visitors! When we were looking at Messier 57 (M57) at zenith, it was good for the viewers to be able to sit in an adjustable height chair.
Of course, I had the equatorial mount motor and (new) controller. This proved, as expected, invaluable for a public viewing event. I could aim at something like Jupiter or Andromeda and then walk away. It was surprisingly useful when I would be away from the telescope for a few moments, maybe chatting with someone or looking up something, and a person would walk up to the 'scope. "Take a look," I would say, knowing it was still on target. That was cool.
§
I don't know if this is allowed but I jacked into the AC power on the DDO lawn. I had brought my long orange 3-prong extension cord and plugged into the east concrete pier. I used this power to run my light table. I wanted to keep the light array separate from the dew heaters, if possible.
Later, Gilles asked if he could gang in.
While Mel was perturbed about us using the round-about for unloading, he made no comment about my extension cord...
§
In a moment of inspiration, I realised what I could do with my (recently found) box of glow-in-the-dark stars. I tossed them on the ground below the telescope. Periodically, I would recharge them with my custom UV flashlight. The kids liked that. I also pulled out my little space alien guy. I would recharge his eyes too!
§
Jupiter was quite good. The moons were well positioned. Io was on one side, shifting its position slowly; Callisto, Europa, and Ganymede, innermost to outer, hovered on the other side. We could make out the light equatorial belt and the dark northern belt. It was difficult to see any other detail with the air turbulence over the Golden Horseshoe.
There were two field stars near Jupiter in my 41' field. (Turns out the bright one, one the same side as Io was ω (omega) Ophiuchus; the faint one between Europa and Ganymede was SAO 184459.)
Someone asked me how far away the moons were from Jupiter. Fortunately, I had that info easily accessible in my palmtop.
At 9:03 PM, the temperature was 21.3° and the humidity was 56%.
§
There were lots of great questions tonight!
For example, at one point, someone asked me if aurora could be predicted. I said that I thought I had seen some web sites for that. I reminded them that it was tied to solar activity. Another asked if aurora was visible in the city. Someone else said they had seen aurora from Yonge St and Hwy 7 (or thereabouts). I suggested that if the intensity was very high, it should be possible.
There was also some discussion about asteroids. I had noted that Vesta was 40' from ν (nu) Scorpius. John might have gone for it but I never heard the end result.
I remembered to refer to my Observer's Handbook on a number of occasions!
§
The ISS (and Shuttle) fly-over at 22:26 was a big hit. I think we had about 40 people on the lawn when it went by! It was so low in the north that it passed behind the big dome! Is that an eclipse? Occultation?
§
A friend of Gilles asked if we could see other planets... We went for Neptune!
I had noted on my plan sheet that Neptune was in Capricornus. But I had not noted where... Oops. Fired up Procyon on the Psion. It showed the planet near δ (delta) and γ (gamma). It took a while, in the murky light dome over the city, to find the brighter (ha!) stars of Cap. Finally, I was able to get my bearings and I put the finder scope on δ and γ. Stars 42, 44, 45 formed a useful asterism above δ. I scanned in the area but without my detailed planet plot I was grasping. When I had paused at one point, Alan looked through the main eyepiece. "What's that?" he asked, indicating a bluish point of light... Now that was a very interesting colour.
I asked John to take a look. He agreed the colour looked right. He suggested that it wasn't until at 200x that you would be able to see the disk. I popped in the 18mm and then added the Barlow. While much fainter, it looked like there was some angular size to the object...
I noted the position of the object with respect to my Tirion chart. It was at the end of the line of 3 faint stars opposite 18 Cap. There was no similarly bright object noted on the chart. I suddenly noticed the dashed line through the Tirion chart: the ecliptic! "That's promising," Alan added.
And I'm pretty sure we found it. With a bit of star hopping, good charts, perseverance, and luck!
§
Cartes du Ciel says Neptune was at magnitude 7.8.
SAO 164444's visual magnitude is 6.64, 164430 is 6.86, and 164400 is 7.11...
The "more stars" and "less stars" buttons in Cartes are very useful! I can better simulate the view in the telescope due to light pollution.
[ed: Confirmed in SkyTools3. The star below Neptune is HD 204692, magnitude 6.6. The next star is HD 204548, mag 6.9. The more distant third star is HD 204220, mag 7.1. Meanwhile, Neptune was mag 7.8 with an angular size of 2.3 seconds of arc.]
§
Alan joined me for the latter part of the evening. I had not seen him for a while. We caught up on life and work.
He had contacted me about the Perseids, wondering what my plans were to view them. I told him that Tayoob and I were kicking about the idea to going to the Torrance dark sky site on Sunday but the weather was not looking good. While interested, Alan did not want to go that far. I pointed out that Saturday night would probably not be an option for me as I was to "babysit."
I invited him to the DDO.
I was a little worried he was bored but he said later he had a good time, was happy with what he saw.
In the end, we only saw about 4 or 5 bright meteors. I was looking at Andromeda when a bright one zipped to the south, parallel to the horizon, leaving a brief glowing wake. Still, it was disappointing.
There's just too much light pollution...
§
Alan cautioned me about the laser usage. I did respond that it was generally understood that we were not to point to aircraft. Alan said he thought it may be illegal! If they could somehow track you down...
§
It was interesting to note that the 74" could not see Jupiter! The elevation was too low. So for those of us on the lawn, we were the only way to see the gas planet.
Visitors also said they enjoyed my view of M57 better than through the 74". While dim, they liked the wider field, could see the overall structure.
§
Why does the DDO use white lights everywhere?! The security light on motion sensor at the front of the dome is incredibly annoying...
Shouldn't they activate red lights during observing nights?!
If nothing else, they should close the blinds at the front of the admin building.
Very ironic.
§
I saw Mars on the drive home...
No comments:
Post a Comment