Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
Search
The Pleiades double challenge
|
I got in a few hours of? observing before my Losmandy mount gave up the ghost with power failure indication. It truly does not like the cold weather. The battery had been sitting for a few weeks so I figured the battery was a bit low. I run the mount off 18 volts usually. This has happened before. Runs fine for two hours then just quits due to voltage drop. But anyways I did accomplish what I wanted to do tonight. Everyone has shown someone the Pleiades but there is more to the story. I looked for hard doubles within the cluster and there are quite a few that are challenging. All look like singles but are not. This is a fun challenge. I used the 5 inch tonight and had to run fairly high power for all but one or two. Here are the ID numbers: Otto Struve 64 SAO 76249 SAO 76236 SAO 76126 SAO 76189 Struve? 450A The G and H components of Alcyone Oh Jupiter had a very fine transit tonight. As Io transited off the face ahead of it's shadow another moon came around from the back of the planet. At the same time as Io was leaving, Ganymede came from in back of the planet on the opposite limb. Pretty good. Two moons right on the limb of Jupiter and one moon shadow. |
|
Holy expletive Mark! ?At least one of those doubles looks maybe on the edge of impossibility. ?SAO 76126 is Celaeno, the faintest naked-eye star of the ¡°seven sisters¡± Pleiades at mag 5.46. ?It has two companions which might be possible (and a third, impossible at 0.006¡±): Sky Safari says the B star is mag 13.2 at 88.4¡± separation, and the C star is mag 11.5 at 217.6¡±. ?That¡¯s six magnitudes difference (!) for the ¡°easy¡± one that I think you intended. ?Extra credit for the B star? ?
?
Oh, but wait, this is all in a bright nebula! ?The Maia nebula, mag 5.4, puts it all in a fog, and the fog is lit up by Celaeno. ?Yeah, that should be a challenge ¨C hope I have a good transparent night to try for that one. ?Thanks for the eyestrain, Mark.
|
|
Naw, draw the line at the ridiculous components! I try to stop at 11th magnitude more or less. Those are challenging enough.I didn't say it was easy :) I just changed the internal battery in the Losmandy. You have to know to set the location and time data quickly or the battery drains. OBTW a GEM mount may help with a few of these! I am keeping the mount control in the house prior to observing. Cold seems to kill batteries pretty quick. But it was most likely time to renew the battery anyways. Probably should be done annually anyways.
On Friday, January 3, 2025 at 12:58:14 PM EST, Roy Diffrient <mail@...> wrote:
Holy expletive Mark! ?At least one of those doubles looks maybe on the edge of impossibility. ?SAO 76126 is Celaeno, the faintest naked-eye star of the ¡°seven sisters¡± Pleiades at mag 5.46. ?It has two companions which might be possible (and a third, impossible at 0.006¡±): Sky Safari says the B star is mag 13.2 at 88.4¡± separation, and the C star is mag 11.5 at 217.6¡±. ?That¡¯s six magnitudes difference (!) for the ¡°easy¡± one that I think you intended. ?Extra credit for the B star? ?
?
Oh, but wait, this is all in a bright nebula! ?The Maia nebula, mag 5.4, puts it all in a fog, and the fog is lit up by Celaeno. ?Yeah, that should be a challenge ¨C hope I have a good transparent night to try for that one. ?Thanks for the eyestrain, Mark.
|
|
Here are my results from the other night. STT 64 did see all three components after about 30 to 40 minutes work. SAO 76126 Just did the AB pair. G&H components not too hard separation, actually easy, but they are dim compared to Alcyone which draws your eye. Easily overlooked in the whole scheme. STF 450A not too bad. Cant remember the others but pretty sure the rational components were seen. I'll have to revisit and write notes. My impression was all were fun. Though some took a pretty fair amount of patience and eye strain. Maybe from your darker site they may be a bit easier. 12th magnitude in these skies is a real ghost. Can be done but you have to want it.
On Friday, January 3, 2025 at 12:58:14 PM EST, Roy Diffrient <mail@...> wrote:
Holy expletive Mark! ?At least one of those doubles looks maybe on the edge of impossibility. ?SAO 76126 is Celaeno, the faintest naked-eye star of the ¡°seven sisters¡± Pleiades at mag 5.46. ?It has two companions which might be possible (and a third, impossible at 0.006¡±): Sky Safari says the B star is mag 13.2 at 88.4¡± separation, and the C star is mag 11.5 at 217.6¡±. ?That¡¯s six magnitudes difference (!) for the ¡°easy¡± one that I think you intended. ?Extra credit for the B star? ?
?
Oh, but wait, this is all in a bright nebula! ?The Maia nebula, mag 5.4, puts it all in a fog, and the fog is lit up by Celaeno. ?Yeah, that should be a challenge ¨C hope I have a good transparent night to try for that one. ?Thanks for the eyestrain, Mark.
|
to navigate to use esc to dismiss