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Mars evening of Sept 9, 2020


mikeDnight
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Amazingly the sky was clear and Mars was blazing brightly as it rose in the east before midnight. I set the refractor up on its mount, rolled back the roof of the observatory and aimed at the planet, not expecting too much. The seeing in my eastern sky hasn't been too steady of late, but tonight was different. The planet was immediately sharp, and the southern detail was well defined without having to wait for the scope to cool. After sketching the Southern hemisphere I'd become more aware of the more subtle detail extending from under the northern cloud and mists around the limb. The CM shows Solis Lacus to be on view and that's what appears in the sketch. Although I've observed this region many times, it nearly always presents itself in a slightly different light, which fascinates me.

The view in the sketch is reversed as seen through a diagonal, and as the diagonal was at a tilt, I simply drew it as I saw it, so south is at 2 O'clock on the disk. I apologize if this messes with your head!

1964168796_2020-09-1013_41_34.thumb.jpg.4c6f389d72ebf7c4b67d5eb6e79ab679.jpg

Edited by mikeDnight
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Very nice sketch.

Can I ask a question?

image.png.42475ef7b89c01526089148e020fe340.png

What does the P mean?  Presumably S points to Mars's south pole and the south pole is defined by us earthlings as the one nearest the bottom as we look at it? (corrected for diagonals on a tilt and/or inverted images etc).

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1 hour ago, globular said:

Very nice sketch.

Can I ask a question?

image.png.42475ef7b89c01526089148e020fe340.png

What does the P mean?  Presumably S points to Mars's south pole and the south pole is defined by us earthlings as the one nearest the bottom as we look at it? (corrected for diagonals on a tilt and/or inverted images etc).

The P means preceding, which is the direction the planet drifts across the field of view. Rotating the diagonal can confuse matters though. If the diagonal was vertical, the south pole would be at the bottom with the terminator (the preceding side in this sketch) towards the left, even though the planet is moving to the right across the sky. :icon_scratch:

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24 minutes ago, mikeDnight said:

The P means preceding, which is the direction the planet drifts across the field of view. Rotating the diagonal can confuse matters though. If the diagonal was vertical, the south pole would be at the bottom with the terminator (the preceding side in this sketch) towards the left, even though the planet is moving to the right across the sky. :icon_scratch:

So you had your head between your legs, Mike?

🙂

 

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Nice drawing Mike.  You were lucky to have such good seeing.  I was using the 120ED at 8.30pm to watch the GRS transit on Jupiter and the seeing was awful.  I could see the GRS only intermitiently, though in better moments you could see flashes of good detail in the EBs.

Back to Mars.  Using the 203/F1200 Bresser in the observatory from around 00.30am, the seeing was initially very good, nice sharp disk, well defined detail and lovely colours (using Baader Contast Booster filter).  The S Polar Cap has indeed been shrinking over the last few weeks, and was very striking, it seemed even smaller than my last obs a few days ago.  I was also struck by the darker  southern albedo areas of the planet looking like a pattern of adjacent circular features, reminiscent (to me at least) of adjoining impact areas.  Your drawing has captured this effect very well.  There was a lot of detail, in these areas, but alas the seeing rapidly worserned as the plant got higher!  I persisted until just after 2.00am by which time the seeing was very poor.  Still, a very enjoyable session, Mars has so much to offer.

 

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1 hour ago, mikeDnight said:

The P means preceding, which is the direction the planet drifts across the field of view. Rotating the diagonal can confuse matters though. If the diagonal was vertical, the south pole would be at the bottom with the terminator (the preceding side in this sketch) towards the left, even though the planet is moving to the right across the sky. :icon_scratch:

Gotcha, many thanks :thumbright:

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1 hour ago, des anderson said:

A stunning sketch, and your observing report is out of this world. Des

Thanks Des. I must be losing it big style as I had a seriously delayed reaction to the "out of this world" quip. It's so bad it made me laugh out loud once it clicked. :laugh2:

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That's a phenomenal amount of detail, captured beautifully as always. Just shows what is possible when an experienced observer with a quality instrument observes under a steady sky. Conversley, when an incompetent observer, with an average instrument meets a turbulent sky.......mush....as happened to me last night! :wink2:

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2 hours ago, paulastro said:

 GRS transit on Jupiter and the seeing was awful.  I could see the GRS only intermitiently, though in better moments you could see flashes of good detail in the EBs.

 

 

Same here, I thought I could see the GRS, but wasn't entirely sure most of the time. Jupiter and Saturn were too close to a roof to blame the seeing though. Mars was fine a few hours later.

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3 hours ago, RobertI said:

That's a phenomenal amount of detail, captured beautifully as always. Just shows what is possible when an experienced observer with a quality instrument observes under a steady sky. Conversley, when an incompetent observer, with an average instrument meets a turbulent sky.......mush....as happened to me last night! :wink2:

A turbulent sky or even tube currents will kill it every time. I seriously doubt you're an incompetent observer though Rob. And of course its good to remember that the detail in any sketch isn't how it first appears through the eyepiece,  But an accumulation of detail recorded after around 15 mins of concentrated observing. I reckon a pencil and sketch pad can improve the performance of any telescope!

Regards, Mike.

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1 hour ago, jock1958 said:

Very nice sketch as always @mikeDnight I was out after 10pm last night but the seeing on Mars just wasn’t up to much so knocked it on the head after catching up on some of my favourites in Cygnus & Andromeda! 

Ten PM would be too early from my site, as the planet would be low and troubled by heat from the town. The best is yet to come though, as Mars rises earlier each night, although it would still be worth staying up late so as to observe it high in the sky and close to the south Meridian. 

Regards, Mike

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26 minutes ago, BRADLEY 1953 said:

GREAT  SKETCH  MIKE, IT REMINDS ME OF RENDITIONS SUBMITTED BY FAMOUS OBSERVERS OF THE RECENT PAST, SUCH AS ANTONIADI, ( with a 830mm refractor) EVEN MORE WORTHY CONSIDERING THE SIZE OF YOUR SCOPE.  CLEAR SKIES.  CHRIS.

I must admit to cheating Chris. I use a binoviewer, which makes a massive difference. :icon_eek:

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Great sketch Mike !

Interesting comparing one of Lowell's sketches to yours (see below). You can sort of see how he came to the "canals" idea. He just took the contrast of the linear features that bit further !

He had a scope 20 inches larger in aperture than yours though :icon_biggrin:

Talking of which, I was at the Lowell Observatory this time last year - what a long time ago that now seems :undecided:

Anyway, sketches. I've cropped and rotated yours to get a closer match, hope that is OK ?:

Percival Lowell, 1894:

Gallery_Image_8368.gif

Mike Hezzlewood 2020 (cropped and rotated):

1964168796_2020-09-1013_41_34.thumb.jpg.4c6f389d72ebf7c4b67d5eb6e79ab679.jpg.65a0117d32b203a62ddcda57e0a865b0.jpg

 

 

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13 hours ago, mikeDnight said:

I must admit to cheating Chris. I use a binoviewer, which makes a massive difference. :icon_eek:

Interesting Mike, might seem like a stupid question, but does it work better because the use of two eyes allows the brain to work better in identifying patterns, or is there some other effect at play? Probably the subject of multiple threads already!

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13 minutes ago, RobertI said:

Interesting Mike, might seem like a stupid question, but does it work better because the use of two eyes allows the brain to work better in identifying patterns, or is there some other effect at play? Probably the subject of multiple threads already!

It's not a stupid question at all Rob. I put it down to the use of twice the receptor size compared to one eyed viewing. With both retinas in use, it really does reveal detail more easily. I was reading a comment on the CN binoviewer forum only this morning, where one astronomer asked his optician why there would be such a marked improvement in planetary detail when using both eyes. The optician said" It's a simple case of 1+1=3".  He may have gone to the same school as me, but in this case the calculation adds up! ☺

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The reason it is better with binoviewing, is not to to with receptor size, it's to do with the physiology of the brain.  When it receives an image from each eye it combines the two images into one image which is better than either of the images from each eye alone.  Its a bit like the physiological version of taking two astro images and playing about with software and getting a single image which is better than either of the two single images. 😄  If you look through just one of your eyes (in the daytime)  and then use both eyes you can see this for yourself.  Luckily our brains have an auto function to do this for us without us having to think about it.

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7 hours ago, John said:

Great sketch Mike !

Interesting comparing one of Lowell's sketches to yours (see below). You can sort of see how he came to the "canals" idea. He just took the contrast of the linear features that bit further !

He had a scope 20 inches larger in aperture than yours though :icon_biggrin:

Talking of which, I was at the Lowell Observatory this time last year - what a long time ago that now seems :undecided:

Anyway, sketches. I've cropped and rotated yours to get a closer match, hope that is OK ?:

Percival Lowell, 1894:

Gallery_Image_8368.gif

Mike Hezzlewood 2020 (cropped and rotated):

1964168796_2020-09-1013_41_34.thumb.jpg.4c6f389d72ebf7c4b67d5eb6e79ab679.jpg.65a0117d32b203a62ddcda57e0a865b0.jpg

 

 

Scary isn't it John!  I admit to being more a fan of Schiaparalli's drawings than those of Lowel.  I first noticed Schiaparalli's canali back in 2003 while sketching Mars using a Tak FS128. It worried me at first, but I soon came to terms with their existence as visual features because they'ed been recorded by numerous observers, and many have even been named. They don't exist in reality of course, but appear to be contrast boundaries that appear where regions of contrasting albedo meet. During the 2003 apparition I remember that on occasions of split second top class seeing, Mars suddenly appeared more like the Moon rather than the featureless orchar deserts that we usually see. It wasn't possible to sketch because as soon as it appeared it disappeared. May be the canals are nothing more than multiple point sources appearing as if linked in the form of a fine grey line. Then again it could be Martians having a laugh!

One of my astronomical hero's, the late Richard Baum, was a brilliant visual planetary observer and a great inspiration to me. The photo below was taken when we last met shortly before he left us. I've also attached a drawing of Mars drawn by Richard and showing the canals. Solis Lacus is towards the right of the bottom sketch.

P2270293a.thumb.jpg.b6d07873ad0140da415c6de5e5c168c3.jpgP2270292a.thumb.jpg.4b7c4e2075c7ba8712c4cee851ea596c.jpg

 

Edited by mikeDnight
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