Shaula in Scorpius

[Tddun]

Hi all,

 

I am currently compiling a list of the top 20 brightest stars to give myself an observing challenge over the course of the year, and I am only including stars visible from the UK (specifically in Essex).

 

Its pretty straight forward, apart from that I am questioning whether one star in particular - Shaula in Scorpius (magnitude of 1.6), is going to be possible or not. As far as I can tell the highest altitude it reaches for observation in Essex is 1 degree above the horizon. I understand if it is possible, it would require some amazing conditions to be visible, and I live close to a location with a clear southern horizon, so it wouldn't be a problem if I had to be extremely persistent to see the star. However at only 1 degree above the horizon, I'm wondering if for all the will in the world it will be impossible from the UK. I'd rather not change my list part way through.

[Paz]

I don't know the answer but one thing that might help you to work out the possibility is to watch the stars rising above the horizon in the east and note at what altitude certain magnitudes become visible.

[Tddun]

Good idea, I'll do a bit of testing to find out.

[furrysocks2]

Good luck with this. Decided to do the very same with a subset of the navigational stars - my list is 40 or so out of the 57.

As for 1 degree above the horizon, no idea but interested to know.

Edit: you perhaps already know about this? https://en.m.wikipedia.org/wiki/Atmospheric_refraction

[goodricke1]

Here is a photo of Shaula 1 deg above the horizon, taken from Waterford in Ireland which is a a very similar latitude to Essex. It's at the lower left with M6 and 7 quite prominent:

[Tddun]

4 hours ago, goodricke1 said:

Here is a photo of Shaula 1 deg above the horizon, taken from Waterford in Ireland which is a a very similar latitude to Essex. It's at the lower left with M6 and 7 quite prominent:

Brilliant, thanks for that! At some point during the summer I will give it a go then.

Would I be right in saying transparency will be a big factor as to whether the star would be visible or not on any given night? And that the transparency would need to be very good.

[goodricke1]

1 hour ago, Tddun said:

Would I be right in saying transparency will be a big factor as to whether the star would be visible or not on any given night? And that the transparency would need to be very good.

Yes I'm sure that's the case. This particular photo was taken looking out to sea and afaik the photographer did not see Shaula visually. His intention was to capture the clusters and was quite surprised when Shaula showed up on the image.