Parade of the planets

[gaa_ian]

With the moon coming to prominence again, I am enjoying a little planetary (and lunar) viewing.
On Mars this morning, could see the polar cap easy at 178x with an obvious dark region near the pole.
Had a go at Mercury, but just got red on one side blue on the other of the image (can someone please explain this:confused: )
Saturn was worth a peek tonight, and jupiter has had great moments of seeing @ 178X.
I seem to keep going back to the seibert Optics 7mm widefield (despite the internal refections)
Jupiter showed great detail including the GRS as it passed the meridian.....
Your experiences ?

[ballaratdragons]

Ian,

You lucky dog getting to see the sky!

Last night I had a few minutes. Tonight I thought I was going to have lovely clear skies but I just checked and its all fog again.

Last night I did notice at around midnight that the Milky Way - especially Sagittarius - was fantastic with naked eyes!

We may have a lot of fog lately but when it thins, the crisp cold air gives astonishingly marvellous sights. Still no good for scopes but terrific for naked eyes. The heart of Sagg really glows bright.

I also enjoyed how much brighter LMC was.

Winter is a great time for the sky!!

[gaa_ian]

Hi Ken
You have to take what you can get with the night sky !
We are coming into our best time of the year here now.
In fact we are having a club StarBQ at our dark site tomorrow night :D
Do you have any clues on the distorted planetary images I am getting ? (See Prev) is it just really bad seeing with the lower Alt. of Mercury ? or something else :confuse2:

[ballaratdragons]

Ian,

It sounds like 'High Humidity - Calm Warm Air' atmospheric distortion. It often causes a 'Rainbow' effect. Whereas Fog, dew, wind, dust and even heat haze tend to make objects change colour rapidly from red to blue (the twinkling effect).

Sounds like you had a warm, humid, still air night.

Another explanation can be a very fine (almost impercievable) layer of dew on your optics. This also causes the Rainbow Effect.

[iceman]

Ian, the red, white and blue of Mercury is evident on all the planets when they are low on the horizon.

It's due to atmospheric refraction.. because you are viewing through more of the atmosphere, and (I think) the different wavelengths of light might get bent in slightly different directions. It's an imagers nightmare and that's why it's always best to image the planets when they are directly overhead, where there is less atmosphere to image through and no atmospheric refraction to speak of (not to mention, seeing is usually best overhead too).

Have a look at this Mercury image I took from last week, you can see the individual raw frame has the red/white/blue that you mention. Luckily, registax has an RGB shift function which re-aligns the Red and Blue channels to make them match up, and produced the much better stacked image.

I'm sure someone will (please) correct me on anything i've said that's incorrect.

http://www.iceinspace.com.au/images/images/planets/20050505-mercuryall.jpg

[ballaratdragons]

You are right Mike.

Different conditions will give different results though.

You call it refraction, I call it distortion. Same things, different names.

[robin]

Ken, we've had some absolutely pristine, clear nights down here on the coast with totally excellent seeing.Only problem is, we've also had a ton of dew.It comes in quick & heavy & after about half & hour, I've got water dripping of my dew cap!
One thing that is an ongoing concern to me is the salty coastal air cant be good on UHTC coated corrector plates......

[gaa_ian]

Thanks Mike & Ken

Ken ... I think you hit the nail on the head there !
Mike ... what you show is very similar to what I saw.
Good to get an explaination, sometimes I wonder if my optics are OK.
Obviously my optics are OK, just a Yukky murky lower atmosphere.

[ballaratdragons]

I can't help with that one Robin. I don't know anything about optical coatings. I do know that Salt air is murder on steel tubes, and gradually depositing fine layers of salt on Newt Mirrors.

Someone else may know about the effects on coatings???

[Orion]

Robin salt mist is a big problem were live but instead of getting it on a corrector plate I get it straight on my mirrors! At times you cant tell it's there until the mirror dries the next day.
My mirrors are quartz coated so I can gently wash the salt of them.

[gaa_ian]

Yep same problem here ...
One of my Dob mirror cleaning efforts was after a night only 500m from the Ocean with a strong onshore breeze.:mad2: