JULY 11TH - A PLANETARY TREAT.

[paulastro]

I was out from 11pm  observing deep sky with my Celestron Starsense Explerer 8 inch dob. Just before 2am I was intending to go to bed - but as mainly a planetary and solar and lunar man, I couldn't resist having a 'quick' look at Saturn with had caught my eye.

For a mediocre morning it took me by surprise, much sharper than I thought it would be.  For a few minutes it looked like an engraving, with hardly a shimmer. The major three rings, and Cassinii's division, were very clear with their contrasting colours and the rings crossing the disc really enhanced the 3-D effect.  Despite the ight hazy sky as well as Saturn I could see Titan, Iapetus and Tethys.

Jupiter further to the East showed a lot of belt detail, though as usual it was less sharp than Saturn - I was using my binoviewer x2 barlow and x2 Vixen 30mm NPLs giving x160.

I was aware Neptune was nearby and I quickly located it with the Starsense. I looked in the binoviewer to see the distinctive small bluish disc, m7.9 and only 2.3".  A lovely sight.

By now I could see Mars which had just risen over a nearby bungalow.  At m0.4 and currently 7.5" it was easy to see its gibbous phase and a couple of albedo features. I'm looking forward to its opposion on Dec 8th when it will be m - 1.9 and 17", and occultation by the Moon on that same morning.

By now it was gone 3 am, but we'll worth missing some sleep.

 

Edited July 11, 2022 by paulastro
Typo

[Altair8389]

Nice report Paul. I did not know Jupiter was less sharp in detail in the belts than Saturn. Is it because Jupiter is so bright ? I saw it the other day, and Jupiter was several magnitudes bright, brighter than Sirius!!!

Do you image with your 8 inch dob much ?

 

Thanks.

Magnus

 

[paulastro]

Thanks Magnus.

At the moment Jupiter is mag  -2.5, Saturn mag 0.5  and Sirius is mag -1.4 of course, so Jupiter is currently around x2.5 brighter than Sirius.  (a difference of one mag equals a brightness difference of x2.5)

It's well known by observers that Saturn 'takes' higher powers better than Jupiter.  There are several reasons for this. The brightness doesn't help, but there are other reasons.  Jupiters detail on the disc is different as seen from earth than Saturn as it has less well-defined detail anyway, Saturn's rings have sharper edges than the disc of Jupiter and the disc of Saturn being roughly twice the distance away and will give a harder edge too.

This morning, Jupiter looked markedly less sharp than Saturn and is affected more than Saturn by poor seeing.  I could easily have used higher power on Saturn, but Jupiter was at its limit in the prevailing seeing.at x160 this morning.

I've only just bought the 8inch and so far have taken one pic of the Moon at prime focus, I use an 80mm ED refractor for solar and also lunar.  I am a visual observer and apart from batteries for my camera, if a pic needs electricity, a driven mount or an equatorial mount, I won't bother 😊.

[Astro_Dad]

Great report Paul, some lovely planetary observing last night then, and excellent to hear the new Dob is working out well. Nice use of the StarSense tech to quickly locate Neptune also - I wish I’d stayed up myself!

Andrew

[paulastro]

Thanks Andrew.  Though, I'm likely to be losing a lot of sleep with the Starsense being such fun to use.  It's just a shame it wasn't invented when I started in astronomy over fifty years ago 😊.