Mars tonight - atmospheric aberration?

[Mand1]

Managed to get a quick look at Mars just now.

Not good seeing at all over next doors roof and the scope not being cooled, but I expected that.

What I wasn’t expecting was the atmospheric aberration (think that’s what it’s called). Blue fringe on one side, red on the other.

Mars was maybe 60 deg above the horizon.. so is anybody else suffering this?

Didn’t really notice it much when I looked at Jupiter and Saturn about 1.5 months ago, and they were not as high.

Last time I viewed Mars was over 15yrs a go thru my first scope - F10 120mm refractor, now I’m using a F6 200mm dob and Hyperion 8-24 zoom

Is it more noticeable in larger apertures?

Edited October 27, 2020 by Mand1

[Dark Vader]

I've been getting a lot of that with Mars through my 200p. Haven't noticed any with Jupiter or Saturn as such but lately they have all been bouncing around a fair bit.

Pretty sure its atmospheric as my collimation looks good (he said knowledgeably) 😃

Andy

[Mand1]

Good, not just me then!

[Dark Vader]

I forgot what it was called - Google says its called atmospheric refraction. I call it a pain in the proverbial... 🙄

[Pixies]

Atmospheric Dispersion? As in "Atmospheric Dispersion Corrector"?

https://www.skyatnightmagazine.com/reviews/accessories/zwo-1-25-inch-atmospheric-dispersion-corrector-review/

[Paz]

It's sometimes called atmospheric dispersion. You can get a corrector (called an atmospheric dispersion corrector) for it which does work but it a bit of extra workload to set up.

I was looking at Mars this evening and had one set up (see below), I don't often observe the planets without it any more.

[JeremyS]

Seeing is Poor here too Again tonight. Not quite as bad as last night but not good enough for any useful observation of Mars.

[markse68]

22 hours ago, Mand1 said:

What I wasn’t expecting was the atmospheric aberration (think that’s what it’s called). Blue fringe on one side, red on the other.

When it’s high I don’t really notice the dispersion but I wonder if the turbulence from the jetstream we’ve had past few nights could make it worse? Does it change as mars moves across the fov? Could be eyepiece chromatic aberration if it does- that seems to get worse with brighter objects and Mars is pretty bright.

Mark

[Mand1]

Hi Mark
It seemed the same across the fov. I think it is definitely atmospheric dispersion, maybe worse due to my local atmospheric condition?

[markse68]

4 hours ago, Mand1 said:

Hi Mark
It seemed the same across the fov. I think it is definitely atmospheric dispersion, maybe worse due to my local atmospheric condition?

oh that’s good news it’s not in your optics then. I wonder if it could be seeing related because with mars as high as it is now (unless you’re viewing it low when it’s on its way up or down?) dispersion shouldn’t really be an issue. I think i saw a bit of dispersion the other night but the seeing was poor with jetstream overhead. The forecast for next week looks like we’ll be clear of the jetstream so fingers crossed for some clear skies!

Mark