Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Effect of being on edge versus centerline

9 replies to this topic

#1 Alex McConahay

Alex McConahay

    Hubble

  • *****
  • topic starter
  • Posts: 13,407
  • Joined: 11 Aug 2008
  • Loc: Moreno Valley, CA

Posted 16 February 2024 - 08:40 PM

Besides the length of totality, what is the effect of watching an eclipse a few miles in from the 100% line, instead of on the centerline?

 

That is, Gramma can watch the eclipse from her home in Columbus, or from her farm in Monroeville (near Norwalk).

 

It would seem to me that, at the deepest part of the eclipse being on the centerline would make for a darker eclipse......After all "Not eclipsed" is not that far away with Columbus compared to Monroeville. In other words, nearly full daylight would be only a few miles away in Columbus.  

 

Anybody have any actual experience with this?

 

Alex

 

 

Here are the particulars of the two spots.

 

 

Attached Thumbnails

  • Monroeville.JPG
  • columbus.JPG


#2 foxwoodastronomy

foxwoodastronomy

    Vendor - Solar Eclipse Timer

  • *****
  • Vendors
  • Posts: 521
  • Joined: 22 Feb 2017
  • Loc: Alabama

Posted 16 February 2024 - 09:28 PM

Alex, I think the duration of totality answers the question: don't you think?  Do the next long eclipse in the USA will be in 2045.  Everything up to that point will require international travel.



#3 Alex McConahay

Alex McConahay

    Hubble

  • *****
  • topic starter
  • Posts: 13,407
  • Joined: 11 Aug 2008
  • Loc: Moreno Valley, CA

Posted 16 February 2024 - 09:37 PM

Alex, I think the duration of totality answers the question: don't you think?  Do the next long eclipse in the USA will be in 2045.  Everything up to that point will require international travel.

I'm not getting an answer in my brain just from time of totality. 

 

What do you deduce from the duration of totality that I am missing as far as what I see during totality?  

 

Remember, I am not asking which is the better place to see the eclipse. I am asking how the experience is different during totality (no matter how long it lasts) from one place to another. 

 

I know where I would go, given my choices of Columbus or Monroeville because I like the longer totality. But during the few seconds at the depth of totality, just how is the experience different?

 

Alex



#4 foxwoodastronomy

foxwoodastronomy

    Vendor - Solar Eclipse Timer

  • *****
  • Vendors
  • Posts: 521
  • Joined: 22 Feb 2017
  • Loc: Alabama

Posted 16 February 2024 - 11:01 PM

Alex, as for your question, at the mid-point of totality, 13.5 seconds in, the corona itself, to the naked eye would not look much different at all.  You just would not have a lot of time to enjoy it. So naked eye, I would think that the visual experience and shape of the corona would be similar to what is seen at a longer duration observing position. However, with long focal length photography there will be differences. The Moon will be slightly off-center so that will affect how you see Baily's beads, the positioning of the diamond rings, chromosphere, and the visibility of prominences.  Since you are on the edge of the umbra the darkness of the sky and the colored horizon will also be asymmetrical.  I would think that overall, the ambient lighting would not get as dark due to being closer to one edge of the colored horizon.  Experiencing all of the partial phase phenomena should be similar including be able to spot shadow bands.  Thinking about it, that is what I can come up with.  I've seen 5 totals, but always close to the centerline.  My shortest was in 2002 at 1m 23s.  That was short!!


  • Ohmless and Alan D. Whitman like this

#5 Alex McConahay

Alex McConahay

    Hubble

  • *****
  • topic starter
  • Posts: 13,407
  • Joined: 11 Aug 2008
  • Loc: Moreno Valley, CA

Posted 16 February 2024 - 11:06 PM

Thanks, Gordon. I had figured on the ambient light thing. But the Beads and proms had not occurred to me. 

 

I shall tell my wife about all this so she knows what to tell Gramma.

 

Thanks to your help, I can now act like I came up with all this on my own. 

 

Thanks for your help.

 

Alex

 

(By the way, I will be far away watching the eclipse without Gramma. )



#6 Retsub

Retsub

    Messenger

  • *****
  • Posts: 471
  • Joined: 08 Dec 2006
  • Loc: Houston,Tx.

Posted 16 February 2024 - 11:31 PM

“But during the few seconds at the depth of totality, just how is the experience different?”

Unless she is quite experienced using binos she’ll miss the limited total time at the edge

trying to see it. 



#7 timelapser

timelapser

    Vostok 1

  • -----
  • Posts: 152
  • Joined: 21 Oct 2022

Posted 17 February 2024 - 12:20 AM

I'm guessing the sky around the sun would be a fair bit brighter near the edge of the path than near the centreline, since it would be getting more light scattered in from outside the path.  So maybe you wouldn't be able to see the corona extending as far out from the sun, so a less spectacular view.  And the planets and bright stars would be less obvious (if you had time to look for them).



#8 Alan D. Whitman

Alan D. Whitman

    Viking 1

  • -----
  • Posts: 566
  • Joined: 14 Oct 2020
  • Loc: South of Penticton, British Columbia

Posted 17 February 2024 - 11:47 AM

There is an Australian professional astronomer on the Solar Eclipse Mailing List who repeatedly argues for observing near the edge. I don't think that he has made many converts, but the fact is that very few serious eclipse-chasers have ever observed from near the edge, so we cannot speak from experience. If I remember correctly, he says that the view of the chromosphere and Baily's Beads will last longer near the edge, which makes sense because of the motion of the lunar disk tangential to the solar disk. But I hope that the weather never forces me to observe from the edge, even though I do consider the chromosphere to be the best part of totality.


  • foxwoodastronomy likes this

#9 SteveInNZ

SteveInNZ

    Apollo

  • *****
  • Posts: 1,136
  • Joined: 07 Oct 2007
  • Loc: Auckland, New Zealand

Posted 18 February 2024 - 02:12 PM

There was a time where mere mortals never got to see the chromosphere at all. There were no PST's, Quarks, etc. It was a thing you saw in astronomy magazines and in documentaries and an eclipse was the only chance of seeing the chromosphere and prominences for yourself. Even though I'm all into the photography, the first time I saw that chromosphere/prom/corona view through a telescope is up there with the first view of Saturn and the first galaxy. I can totally understand why people might want to extend that experience.

 

Steve.


  • Alan D. Whitman likes this

#10 Alan D. Whitman

Alan D. Whitman

    Viking 1

  • -----
  • Posts: 566
  • Joined: 14 Oct 2020
  • Loc: South of Penticton, British Columbia

Posted 18 February 2024 - 03:19 PM

There was a time where mere mortals never got to see the chromosphere at all. There were no PST's, Quarks, etc. It was a thing you saw in astronomy magazines and in documentaries and an eclipse was the only chance of seeing the chromosphere and prominences for yourself. Even though I'm all into the photography, the first time I saw that chromosphere/prom/corona view through a telescope is up there with the first view of Saturn and the first galaxy. I can totally understand why people might want to extend that experience.

 

Steve.

Well, Sky&Tel has me pegged as a deep-sky observer because almost all of my articles for the magazine were about that aspect of astronomy. But every time that I saw chromosphere, prominences, and corona through a telescope ranked far above any view of Saturn (even the time that there were spokes) or any view of any galaxy! For me, total solar eclipses are a totally different level of experience than anything else in astronomy.


  • SteveInNZ likes this



Reply to this topic



  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics