I knew this wouldn't fool you for long...
Todo tuyo, IMO

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Non sunt multiplicanda entia praeter necessitatem.

Didn't Frank Drake also make an interesting observation that was unrepeatable?


Galileo is the of course the right answer.

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"I will do my best to understand and explain the universe from big to small without invoking miracles, unrepeatable events, or divine intervention. In place of those things I will use observations, mathematics, and science."


-Cross
My travel blog

Some of my Astrophotography


Those that lack education have a hard time understanding its value. - Cross

Next question:
Towards the end of the 20th century, some of our ideas about Mercury and Mars were mistaken, in part because of conclusions drawn by this astronomer from his own observations. Name the astronomer, the mistaken idea, and how it was corrected. Extra credit: At what observatory were his observations carried out.

Taking a pre-google lunge, I'll guess the obvious -Lowell? [I'd answer more but I am also guessing I'm wrong. ]

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Lighten up! This is a stellar board!

Lowell? End of 20th century (Or was that a typo?)? Mercury?
I am back from my google lunge (and hard landing). I can only say:

Hint?

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Non sunt multiplicanda entia praeter necessitatem.

I tried Googling the other day (despite Wolverine's comment to me about the restaurant ) and read tons about Mercury, but couldn't figure this one out. Mercury really throws it off. Do you think IMO has put everyone on a wild goose chase? And where is he??

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

I remember seeing a sketch of Mercury that looked much like Lowells drawings of canals on Mars. So my guess is Lowell and Mercurian canals.

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I'm not a scientist, but I play one on the internet.
http://www.rrac.org

But still this question is about the late 20th, not 19th century. I think IMO wants us to find out how a respectable scientific opinion on the planetology of the two bodies was refuted by (which?) observation.

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Non sunt multiplicanda entia praeter necessitatem.

Yes ... second half of 20th century. Hint: sketches of Mercury were involved as were observations of stellar occultations by Mars. The physical characteristics involved were very different in the two cases.

Sorry ... he was off trying to figure out how to clean mildew/mold off the primary of a Celestron Nexstar ... any ideas anyone?

This is driving me nuts, IMO. The only person who I can find that had a wrong assumption about Mercury that fits this time period is Eugenios Antoniadi: http://www.daviddarling.info/encyclo...Antoniadi.html. But he died in 1944...is that too early? That wrong assumption was corrected in the 1960s, then by Mariner 10, but his Mercury map was used for years:
http://www.vt-2004.org/////mt-2003/m...y-mapping.html

So, if that's wrong, too, at least I learned something.

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

IMO did not say when the erroneous views were established, that was my only real hope. I just wanted to help ya'll get past my shallow end of the pool.

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Lighten up! This is a stellar board!

OK, if I scratch my Antoniadi idea then I'd have to go with Giovanno Schiaparelli, because he watched a Mars opposition and created the most detailed map of Mars AND he figured Mercury's rotation all wrong. He was at the Brera Observatory in Milan Italy. His ideas about seas and water on Mars were shattered by the Mariner 4 in 1965. His idea about Mercury's rotation was killed by the Arecibo Radio Telescope. (Though apparently others had some ideas about the temperature of the alleged "far side" of Mercury). Then Mariner 10 mapped it.


I don't think Lowell fits the Mercury aspect, and then IMO would have told y'all if you were correct. But what do I know?

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

That's who first sprang to my mind - erroneously believing in the synchronous rotation of Mercury and unwittingly starting all that Martian canali thing. But these errors were corrected well before the end of the 20th century, so ...

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The hint about Martian stellar occultations tends to make me think that part of the answer has something to do with the Martian atmosphere but I haven't been able to find any references to that or to how it applies to Mercury. There is the finding about possible ice in polar craters on Mercury...

Dave Mitsky

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De gustibus non est disputandum.
Never attribute to malice that which can be adequately explained by stupidity.

I don't know if you saw, but IMO gave a second clue in reply to Arneb:
So I took that to mean that the corrections could be from 1950 on. I liked my Antoniadi idea at first, because he too had Mercury's rotation wrong, but only Mariner 4 could conclusively show there were no seas on Mars as Schiaperelli thought. Antoniadi had already criticized Lowell.

IMO needs to get out of bed.

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

It says in my Mars magazine that French astronomer Audoin Dollfus reportedly detected water vapor in the Mars atmosphere in 1963, but I don't think he had anything to do with Mercury whereas Schiaparelli did. Plus there's this business about occultation.

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

Where did Dolfus (only one "L") observe from? What other observations did he make?

(Incidently, the observations involved were in the mid-20th century, the correction, of course, some years later.)

Geesh, he was/is at the Meudon Observatory (but all the Pic-du-Midi) where Antoniadi was. The sources I looked at all spell his name with two L's. I'm going to be late for work, so the answers are in here, among other places:
http://www.bpccs.com/lcas/Articles/dollfus.htm

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

Darn ... You are right about the 2 LLs ... Ive been misspelling his name for years ... but that article does not even mention several other of his observational results ... and he did observe from Pic du Medi.

So, is that the answer--Dollfus? Let me tell you, other than the fact that I was dancing around a link to him in the link above for Antoniadi...




...he gets ONE sentence in that whole latest Mars magazine; it's mostly all Lowell, Lowell, Lowell, which I don't think is even right considering Antoniadi thought his lines were nonsense. Dollfus is not mentioned at Nine Planets, in my books, etc, etc in any of the chapters on Mercury. He gets short bios in most places. Now, maybe the French Wikipedia says more, but I don't feel like reading French this morning.

So, at this point I'm bowing out of this investigation. Either the guy is underrated or something, but maybe you should just explain it.

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

I will post a bit more info tomorrow ... the lack of large amounts of info may be a result of folks not wanting to press a pair of embaressing misconclusions.

OK ... perhaps this question went too far into ancient history for you young folk. I recall a meeting at Cornell about 1967 or so at which some very unkind things were said (unfairly I thought) about Dollfus. At any rate, here is a brief rundown of the story as I recall it, with some references to web sites:
Mercury Rotation:
Dollfus carried out a long and careful series of observations of surface markings on Mercury. From these he concluded that the best fit rotational periods were 88 days (synchronous) and 59 days (the actual value accepted today). Unfortunately he then took this analysis as a confirmation of (the universally expected) synchronous rotation. A brief mention of the erroneous Dollfus conclusion is found in
muspin.gsfc.nasa.gov/download/docs/proceedings/1999/Stanton_Peale.pdf
It turns out that two out of three observations made at maximum elongation as seen from Earth will fit either period.

Mars Surface Pressure:
As plans developed for the first US launched Mars landing spacecraft, the use of a large parachute was considered feasible partially based on an estimate of the surface pressure of 85 millibars made by Dollfus. Later observations suggested that perhaps this estimate might be too high by up to a factor of 10 (it was) and retro-rockets were used instead.

References to the pressure estimates may be found in
http://www.uapress.arizona.edu/onlin...ars/chap10.htm and http://www.hq.nasa.gov/pao/History/SP-4212/ch1-2.html
Interestingly, the NASA publication states whereas the actual value (about 6.8 mbars) may be seen at http://mars.sgi.com/ops/asimet.html . The Viking data also showed an average value of about 8 millibars, not the 75 millibars quoted in the NASA publication (see http://www-k12.atmos.washington.edu/..._overview.html )

I don't think it's age so much as available information--after all, Lowell and others were way before our time. Your profile says your occupation is "astronomer," which I take to mean not an amateur astronomer; given that frame of reference, you would be more aware of all the "minor" players in the field. (I say "minor" in the sense that their names aren't splashed all over mainstream astronomy books, not that they or their research is insignificant).

If Dave hadn't made his comment about atmosphere I wouldn't have investigated Dollfus, (hat tip to Dave), but I don't feel good getting an answer right without really understanding why, and by open-book, no less. At least I learned something! However, in the interest of moving the quiz along, I'm going to ask a question:

This woman astronomer, in my lifetime, has discovered/co-discovered more than 800 asteroids. She is retired now, but she worked at a famous facility. One unusual asteroid she discovered is notable for at least two reasons--one reason VERY notable as it was a "first" of something.

Who is she?
What is the asteroid's name?
From where did she discover it?
What is its unusual feature officially called?
Where did she work?

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

I looked for unusual asteroids discovered by this astronomer, but found none. So I'll risk getting egg on my face by supposing that you may have mixed up "asteroid" and "comet" in one part of the question.

Carolyn Shoemaker
Comet Shoemaker-Levy 9
On 24 March, 1993 - hey, that's exactly thirteen years ago today! from Mount Palomar observatory (the 18" Schmidt)
Cometary fragmentation; impact on another Solar System body
She was a visiting scienist at the USGS atrogeology lab in Flagstaff, Arizona. She worked there with her husband.

So did I fall into the trap? The expression "official" for the unusual feature makes me uneasy...

Since Melusine is always frinedly with me, I'll risk it

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Non sunt multiplicanda entia praeter necessitatem.

Bzzzzt! Egg on the face is supposed to make a good facial--good for tightening those pores.

Geesh, Arneb, I didn't name myself after a myth/asteroid (Melusina) for no good reason! You got one thing right in your answer, but you are incorrect over all. This is definitely an asteroid. It's funny-looking, too.

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

I'm already feeling the wrinkles disappear.

Well, it was worth a quick shot between patients. It's not personal, as slips of the tongue do happen - it might have happened even to you, I thought.

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Non sunt multiplicanda entia praeter necessitatem.

I shouldn't answer but I knew this right off (I was lucky enough to spend two summers at JPL and met her) so here goes:
Eleanor Helin
107P/Wilson-Harrington
Palomar (? I think)
its both a comet and an asteroid
JPL

See http://en.wikipedia.org/wiki/Eleanor_Helin for more

IMO, You have everything correct except the asteroid and its feature. It was a first of something, and it's not Wilson-Harrington, it's an asteroid. Again, it's funny looking, but there's a name for that, too.


*Arneb, I'm just jostling with you. I don't think you're capable of really annoying me.

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Sunset

Die Sonne scheidet hinter dem Gebirge. In alle Täler steigt der Abend nieder
mit seinen Schatten, die voll Kühlung sind.

2062 Aten, the first of the Aten asteroids?

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- Learn a lot teaching others.