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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4301
Loc: Inner Solar System
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Can we talk about this some more? It's an interesting book and topic. Maybe we could squelch the sniping.
William Corliss, in his "Sourcebook" project volume called "The Moon and the Planets", prints the letter from Mellish to Leight, and rates the data "3" which is fairly poor (at the time all there was to go on was the letter), but rates the anomaly as a "4", which means there's no reason to doubt Mellish's observation, since Martian craters can be very large and it's entirely reasonable for someone to have seen them from time to time.
(BTW, among Corliss' references for this listing is an article by Mr. Gordon, author of "Craters").
Corliss' books are a good addition to anyone's library. He reports on anomalous observations, examines the data, and determines if there's anything to it. He presents some unusual reports, but examines them quite objectively.
- Rick
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- Rick
14" LX200GPS
8" Meade 826C
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trainsktg
Post Laureate
Reged: 08/23/05
Posts: 4497
Loc: Pacific Northwest
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I promise I'll be good 
I've been doing some reasearch on this topic in the interum cool off period. I'll list some of my findings now.
Regarding Mellish:
Observing and Photographing the Solar System (Dobbins, Parker, Capen 1988), page 67 - it states that "During 1982...Barnard discerned several Martian craters as dark circular patches with the Lick 36" and "with the 40" Yerkes...Mellish glimpsed a host of bright rimmed craters." It states at the end of the paragraph that Barnards drawings have not been located, but Sheehan discovered these in 1988.
Gordon's research points out that the 'large crater' Mellish observed in 1915 is Argyre, of 868 km diameter (1,100 counting the surrounding mountain ring). At the time Mars was 7.7 sec arc, and using the 40" Yerkes refractor at 1,100x, Argyre would have subtended about 1" arc which is nearly 10x larger than the 0.11 sec arc resolving power of the telescope. The seasonal aspect shows that Argyre would also have had frost on them, which is how Mellish described them and as Mariner 4 verified.
More to follow, later tonight.
Keith
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He was a good little monkey and always very curious.
Edited by trainsktg (08/14/07 08:20 PM)
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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4301
Loc: Inner Solar System
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Argyre would certainly fill the bill.
It seems odd, though, that Mellish apparently did not recognize what he was seeing. If he had observed Mars for any length of time, it seems like he would have known it was Argyre by the other albedo features visible, and said something to the effect of "Guess what - Argyre is a crater!". Were Mars maps fairly standardized at that time, that is, would Argyre have necessarily been labled on the map he was using? What map was he using?
Or, was he fairly new to Mars observing, and possibly wasn't familiar with the features? His drawings hint at this latter idea: His 15 sketches in the book don't really look like anything I've ever seen on Mars. (Of course, neither do Percival Lowell's).
- Rick
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- Rick
14" LX200GPS
8" Meade 826C
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desertstars
Deja moo
Reged: 11/05/03
Posts: 30032
Loc: Tucson, AZ
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My apologies. I meant to unlock the thread after a suitable cooling off period. Flat out forgot about it.
Carry on.
Politely... 
--------------------
Tom W.
SVP8 'She turned me into a 3-legged Newt' EQ
Ralph, the All-Purpose 102mm Refractor
Under the Desert Stars
Alcohol and calculus do not mix. Please don't drink and derive.
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trainsktg
Post Laureate
Reged: 08/23/05
Posts: 4497
Loc: Pacific Northwest
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Some more interesting quotes:
G.D. Van Couleurs, using 600x on the USNO 61" reflector in Flagstaff, "The dark floor of a large crater Huygens is outlined by a dark circular ring. It is one of the few Martian craters detectable with ground-based telescopes. I saw it well last October 5th (1988)...." (S&T, January 1989, pg. 16)
S.J. O'Meara, using the 60" Mt. Wilson reflector with orange filter states he saw "numerous dust filled craters." (from S.J O'Meara's 1988 opposition notes). Of note, that when meeting with Gordon at 2007 NEAF, O'Meara gave permission for him to use any of his quotes in any future article.
Gordon has also shared with me a letter sent to him from Tom Cave (dated 1999), where on August 10, 1956, he describes using the 100" Mt. Wilson reflector at 3,200x with Dr. Robert Richardson. "In the deserts north of Sinus Sabaeus we saw a number of dark and circular oval spots which Bob and I both felt were craters." Something I didn't realize...Thomas was a prolific observer, not just a maker of fine telescopes. In his lifetime he observed with the 200" Hale, 100" and 60" Mt. Wilson, 40" Yerkes, 36" Lick, 33" Meudon, 24" Lowell to name a few. Some of us were lucky to just hit maybe one of these when we were 6 years old on a family trip!
Was Mellish inexperienced? Argyre was on maps of the period, but at that time of year Argyre and Iridium Montes were frost covered, increasing their visibility, plus there was added enhancement of the topographical relief due to the terminator shadow. Gene Cross' computer simulation shows Argyre on the terminator at the time of Mellish's sighting. Mellish estimated that the crater was 3-4 miles deep. We now know that from the top of Iridium Montes to the bottom of Argyre is 6km, right in the middle of Mellish's estimate. His major mistake was estimating the crater's diameter to be only 320km, but this can be explained by the foreshortening of the crater due to it being on the limb. Mellish was actually hired to hunt for comets for 9 months, but he was doing such a good job that they kept him an additional 6 months until the grant money ran out. He actually also discovered Hubble's Variable Nebula, but he reported it as a comet (not recognizing what he had found) so the honor went to its subsequent 'discoverer'.
Keith
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He was a good little monkey and always very curious.
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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4301
Loc: Inner Solar System
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It's hard to argue with an observer of O'Meara's caliber, especially when looking through the 60".
My only question about Mellish would be, did he recognize Argyre. Of course, the foreshortening, along with the shock, could have made him think he was seeing some other, unknown feature. It's hard to second guess this far down the road.
But he did step forward and say "Craters!" before anyone, and plenty of people have done so since then.
And, like someone said earlier (I think it was me), Mellish said he saw a big crater; and there's a big crater right where he said he saw one. Those are facts, and everything else is conjecture.
Re. Hubble's Variable Nebula: Ain't that always the way!
- Rick
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- Rick
14" LX200GPS
8" Meade 826C
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trainsktg
Post Laureate
Reged: 08/23/05
Posts: 4497
Loc: Pacific Northwest
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Quote:
Mellish said he saw a big crater; and there's a big crater right where he said he saw one. Those are facts, and everything else is conjecture.
All of the anecdotes, quotes and calculations are great for discussion, but that statement is probably the best summation of the whole subject.
Keith
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He was a good little monkey and always very curious.
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trainsktg
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Reged: 08/23/05
Posts: 4497
Loc: Pacific Northwest
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This is interesting. Astronomy June 1995, pg 20...Jim Bell from Nasa, in an article entitled 'Mars in Hubblevision', states "We're resolving Martian volcanos right down to their calderas (central craters). We also see obvious lanes, gaps, and irregularities in the north polar cap." What I find interesting about this is that Hubble was seeing this type of detail at opposition with no shadow relief. Mellish recommended observing Mars near quadrature to maximize shadow relief along the terminator.
Keith
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He was a good little monkey and always very curious.
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desertstars
Deja moo
Reged: 11/05/03
Posts: 30032
Loc: Tucson, AZ
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Well, when you don't have the HST handy, you need all the help you can get.
--------------------
Tom W.
SVP8 'She turned me into a 3-legged Newt' EQ
Ralph, the All-Purpose 102mm Refractor
Under the Desert Stars
Alcohol and calculus do not mix. Please don't drink and derive.
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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4301
Loc: Inner Solar System
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We're finally getting a break in the monsoon, and I'm hoping for a try at it this weekend. Mars is placed about as well as it can be right now. Ever since reading Rodger Gordon's book I've been excited about this, but the weather hasn't been cooperating.
- Rick
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- Rick
14" LX200GPS
8" Meade 826C
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trainsktg
Post Laureate
Reged: 08/23/05
Posts: 4497
Loc: Pacific Northwest
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Good luck.
I got a morning shot about a week ago. Its been rain since then. I'll be breaking out my 8" f8 Edmund reflector this weekend if it clears up.
Keith
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He was a good little monkey and always very curious.
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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4301
Loc: Inner Solar System
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To revive the thread about Rodger Gordon's "Observing the Craters of Mars":
Here's a quote from Al Nagler's essay on the Ethos on the TeleVue web site:
"Right after NEAF in April, Rodger Gordon, the acknowledged "eyepiece junkie" of all time, wrote me "Definitely the finest wide-angle eyepiece I've ever seen. If God is an astronomer, this is the wide-angle eyepiece he'd choose. You can quote me." Thanks, Rodger. I waited until now to avoid "priming the pump", so to speak before quoting your unbridled enthusiasm publicly."
Not to start an Ethos thread, but: did you catch this?
Al Nagler values Rodger Gordon's endorsement enough to use it in his web page. This is the very same Mr. Gordon who has written this book; an outstanding observer with an encyclopedic knowledge of optics and observing, and a long history of accomplishment and publication.
If you haven't checked into it yet, you might still be able to get a copy.
Excuse my enthusiasm - I just really think this is an important book.
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- Rick
14" LX200GPS
8" Meade 826C
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trainsktg
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Reged: 08/23/05
Posts: 4497
Loc: Pacific Northwest
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Hi Rick,
Not wanting to turn this into an Ethos discussion either, but I'd like to add a little information about Rodger's quote regarding the Ethos. Rodger is definitely NOT a Naglerite and is as quick to report an optical deficiency in an expensive Televue product as he is a generic eyepiece that costs $50. When he told me that this is the best wide field eyepiece he has ever looked through, period, I knew I had to get one  .
Keith (Oh, and I'm starting to pull some detail out of Mars . No craters, yet, though  . )
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He was a good little monkey and always very curious.
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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4301
Loc: Inner Solar System
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Quote:
Hi Rick,
Not wanting to turn this into an Ethos discussion either, but I'd like to add a little information about Rodger's quote regarding the Ethos. Rodger is definitely NOT a Naglerite and is as quick to report an optical deficiency in an expensive Televue product as he is a generic eyepiece that costs $50. When he told me that this is the best wide field eyepiece he has ever looked through, period, I knew I had to get one .
Keith (Oh, and I'm starting to pull some detail out of Mars . No craters, yet, though . )
Hey Keith,
That's weighing heavily on my mind (and wallet) too. The price is the only thing holding me back at this point, but I'm weakening...
There's still hope for craters, etc., as long as we're not too far from quadrature. At ~02:00 AM, when I do my Mars observing, Olympus Mons is now near the terminator. I keep hoping to see a hint of shadow, but so far I haven't. I'm going to turn the big scope on it this weekend. My one sighting of Huygens crater in 2005 gives me hope.
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- Rick
14" LX200GPS
8" Meade 826C
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David Knisely
Postmaster
Reged: 04/19/04
Posts: 6784
Loc: Beatrice, Nebraska
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Quote:
Quote:
Hi Rick,
Not wanting to turn this into an Ethos discussion either, but I'd like to add a little information about Rodger's quote regarding the Ethos. Rodger is definitely NOT a Naglerite and is as quick to report an optical deficiency in an expensive Televue product as he is a generic eyepiece that costs $50. When he told me that this is the best wide field eyepiece he has ever looked through, period, I knew I had to get one .
Keith (Oh, and I'm starting to pull some detail out of Mars . No craters, yet, though . )
Hey Keith,
That's weighing heavily on my mind (and wallet) too. The price is the only thing holding me back at this point, but I'm weakening...
There's still hope for craters, etc., as long as we're not too far from quadrature. At ~02:00 AM, when I do my Mars observing, Olympus Mons is now near the terminator. I keep hoping to see a hint of shadow, but so far I haven't. I'm going to turn the big scope on it this weekend. My one sighting of Huygens crater in 2005 gives me hope.
Well, what is seen with amateur telescopes at the location of Huygens is a dark area mainly on the floor of the crater and the lighter albedo around it, but not the crater itself. The walls are far too small to be resolved from Earth (even HST can barely show Huygens), so what is being shown is more of an albedo feature rather than a topographic feature. Clear skies to you.
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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
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desertstars
Deja moo
Reged: 11/05/03
Posts: 30032
Loc: Tucson, AZ
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This has strayed far from being a thread about the book, and is well into observing territory. That makes it a bit off topic for a Stellar Media forum, guys.
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Tom W.
SVP8 'She turned me into a 3-legged Newt' EQ
Ralph, the All-Purpose 102mm Refractor
Under the Desert Stars
Alcohol and calculus do not mix. Please don't drink and derive.
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desertstars
Deja moo
Reged: 11/05/03
Posts: 30032
Loc: Tucson, AZ
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Discussion of books and information media available to amateur astronomers describes the purpose of the stellar media forum. Discussion of observations or the techniques for making those observations belong in the Planetary and Solar System Observing forum. We make such distinctions in the hope of at least trying to place information in the forum people are most likely to look when they develop an interest in a topic, and come to Cloudy Nights with a question.
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Tom W.
SVP8 'She turned me into a 3-legged Newt' EQ
Ralph, the All-Purpose 102mm Refractor
Under the Desert Stars
Alcohol and calculus do not mix. Please don't drink and derive.
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