LtE in CMO #245

From Thomas A DOBBINS


@. . . . . . You recently wrote:

"Anyway we sincerely hope the US observers will be successful soon again, and we would like at this moment to congratulate Tom DOBBINS and W SHEEHAN on their wise prediction and a successful organization of the powerful team including Don to the Florida Keys."  Thank you for your kind and flattering remarks. On this occasion I would be remiss if I did note make a note of the fact that the reports of "flares" by Saheki, Tasaka, et al have long been regarded with undue skepticism in many quarters and all too often relegated to the fringe. It must be very gratifying that any lingering doubts about the validity of the observations by your countrymen must now be abandoned. As you will soon see when sequences of still images are extracted from our videotapes, Saheki's drawings of the July 1, 1954 flare at Edom are strikingly similar to the event that we have just witnessed. It can now be said that the accuracy of his depictions of the phenomenon is truly uncanny and worthy of the highest praise. Notable in this regard is the fact that Saheki recorded a transitory elliptical indentation in the southern edge of Sabaeus Sinus accompanying the anomalous brightening; moreover, his depiction of the 1954 flare at the instant of maximum brilliance mimics our impression that Sinus Meridiani appeared momentarily detached from Sabaeus Sinus.

 With warmest regards,

(8 June 2001 email)

@……….The following NASA image may be of interest and worthy of reproduction in CMO:

http://www.msss.com/mars_images/moc/5_24_98_glint_release/index.html

 

(9 June 2001 email)


Tom DOBBINS kindly showed us some interesting passages that had not survived the final edition of The Martian-Flares Mystery by T DOBBINS and W SHEEHAN (the May issue of the S&T).

 

The question of attempts by inhabitants of Mars to communicate with Earth by means of mirrors aside, the possibility of observing natural reflections from Martian seas was also considered. …..

   On the basis of what was admittedly only circumstantial evidence, the dark areas had been interpreted by most early astronomers as bodies of water…..

This had been Schiaparelli's view of the matter. Summarizing the conclusions he had reached from his observations in 1877, the sage Italian astronomer had written: "We can readily accept the supposition that the bright areas on Mars are its continents, and the dark parts seas... During the course of my observations I have noticed another fact, which tightens still more the knot of analogy between Mars and the Earth. Studying the colors of the different seas of the planet, I have found that, generally speaking, the color of the seas in the equatorial part of the planet is darker than elsewhere, and becomes lighter with increasing latitude. Now the same observation has been made by sailors on Earth, many of whom are convinced of the difference of color between the Mediterranean and, say, the Baltic or the North Sea."

  However, Schiaparelli also noted that some regions on Mars have the muted intensity of halftones, and he suggested that they were probably swamps or marshes rather than proper seas. Moreover, indisputable hanges in both the size and intensity of many of the dark areas had been recorded over the years, suggesting that the Martian seas must be shallow and their shorelines very flat. Eventually Schiaparelli found it necessary to caution against too literal an acceptance of his naming of Martian  features after "seas, lands, rivers, canals, gulfs and lakes."

If there really were seas on Mars, as was then generally believed, one predictable  consequence flowed from it. Whenever the observing geometry was just right, bodies of water on Mars ought to produce brilliant specular reflections of the Sun. As early as 1863, the British geologist John Phillips had suggested that the failure of astronomers to observe such reflections could only mean that the dark areas must be something other than seas.

  Schiaparelli himself calculated that the subsolar reflection ought to rival a star of the third magnitude star in brilliance. Eventually the failure to observe such reflections was reconciled to theory by simply abandoning the maritime view of the planet. During the 1890s, the once dominant view of the dark areas as seas lost ground - or rather lost water - and they came to be widely regarded as tracts of vegetation. As Percival Lowell summed up in his influential book Mars and Its Canals: "….

  Specular reflection of the sort was early suggested in the case of Mars, and physical ephemerides of the planet registered for many years the precise spot where the starlike image should be sought. But it was never seen. …." Lowell's words testify to what would become the non-expectation by astronomers of seeing specular reflections on Mars. In fact, the failure of such phenomena to appear seemed to argue not only against the existence of seas on Mars, but against the existence of any bodies of standing water of any significance. Refining Schiaparelli's calculations, the Russian astronomer Vasili G. Fesenkov would later estimate that any open expanse of water more than 300 meters across should make its presence known in this way. And not only liquid water, but ice as well, for a smooth surface of ice is no less capable of serving as a mirror. ….


 Tom DOBBINS (OH, USA)

kmdobbins@coshocton.com


 Back to the LtE Home Page

 Jump to the LtE Archives