Jump to content

Banner.jpg.b83b14cd4142fe10848741bb2a14c66b.jpg

Where are the Canali?


JohnSadlerAstro

Recommended Posts

Hi,

I was reading W E Johns' sci-fi book Kings of Space, which pre-dates space flight and is very over-optimistic about life on other worlds etc. One part left me rather confused: the Martian Canali. In the book one of the characters explains how they were spotted by Schiaparelli and mapped by several astronomers (and are later discovered by Johns' explorers to be inhabited by giant swarms of killer mosquitos). It's now known that these do not exist, and the standard explanation is that they were simply an optical, visual, or mental aberration that was mistakenly identified as an actual surface feature.

However, although many astronomers were really certain that the canali existed back then, I've never heard of anyone seeing them more recently? As they were an aberration of some sort, surely certain types of scope will still show them, perhaps the scopes that were actually used to map them? ??

Or should Schiaparelli  just have gone to Specsavers? ?

John

Link to comment
Share on other sites

Mars in a friend's 130mm Vixen apo had such brutal contrast you could have thought the separation between lands was artificial. Like strokes of different paint colors. There's no way vintage oversize achromats were figured and polished as finely as that Vixen is, but they were huge, so they had lots of resolving power, and vintage observers made heavy use of colored filters to erase chromatic defects and reinforce contrast.

That plus matching the aperture to turbulence thanks to many sizes of diaphragms, could also create very strong contrast between martian features, which could pass for artificially built lines.

But that's only my personal idea based on limited knowledge and armchair reasoning, I have not observed Mars through these old refractors myself.

Link to comment
Share on other sites

Probably the greatest telescopic observer of all time was E.E. Barnard and possibly the greatest comment ever made at the time were his five words on the matter: I can't see 'em.

If Percival Lowell had had more humility and less money he might have listened.

Olly

Link to comment
Share on other sites

It does seem a great shame that Lowell's reputation suffered badly as a result of canals on Mars debacle. He  ought not  to have got involved.  The thing is, so many people today are expectant of a long gone Martian habitation of the Ref planet, and  so many reports of strange objects being found, albeit by photographic means, I do believe these psuedo discoveries are faked to promote interest in Mars, and the moon. Lowell should be vindicated, for no other reason, than we are still applying guesswork in century 21.

It will take much physical examination of Mars, to the extent of digging deeply into the planet in order to finally establish that no life, except perhaps some lichen ever existed there.

I got excited as a youngster, listening to a serial on radio. Jet Morgan and his pals Journey to Mars. I read the Eagle Comics too.I hoped, but I doubt anything will turn up.

Link to comment
Share on other sites

Hi,

So there are a lot of theories about what they actually were. Possibly the "sightings" were from a combination of those? ?  

It would be really interesting to actually look at Mars through those great refractors and see what it looked like, I think the Lowell one is still in existence? 

It is rather disappointing though. :( A river cruise on martian waterways would be quite a nice holiday.

John

Link to comment
Share on other sites

Perhaps of similar origins are the now rarely discussed Transient Lunar Phenomena https://en.wikipedia.org/wiki/Transient_lunar_phenomenon

Ok, there have been a number of probable meteorite impacts that have been recorded from Earth but most of the classic transients were never backed up or confirmed.

My guess is that if people still read the old books that mention TLP's, there would continue to be regular "sightings".

Link to comment
Share on other sites

There are observing campaigns for TLP.  NASA has some software for checking your lunar images, BAA has details of how to do it, and Aberytstwyth Uni (for one) has a whole research project on it http://users.aber.ac.uk/atc/tlp/tlp.htm.  When I went to Pic Du Midi with Europlanet in the summer I spent part of one night observing with Tony Cook (from Aber) looking for TLP.  Here's report

image.png

Link to comment
Share on other sites

When I was imaging the moon several years ago with a debayered DSLR I had a triangular image of a spacecraft on the surface of the moon.  It turned out to be faulty pixels from the debayering process.  Not everything is what it appears to be!!

Link to comment
Share on other sites

I've not seen any Martian Canali but I have witnessed two TLP's over the years. The first was spotting a point of light inboard of the dark lunar limb, I was setting up a newly self built 5" refractor. After a few seconds I went indoors for a higher power eyepiece but by the time I returned, it had disappeared. I was familiar with stellar occultations and this sighting was in twylight. The second occasion was seeing a noticeably blue haze on the floor of the crater Aristarchus. This crater has a very high albedo, easily showing CA in an achromat but the telescope in use was a Maksutov so essentially CA free. My TLP ambition is to see an impact flash.  ?

Link to comment
Share on other sites

5 hours ago, Gina said:

When I was imaging the moon several years ago with a debayered DSLR I had a triangular image of a spacecraft on the surface of the moon.  It turned out to be faulty pixels from the debayering process.  Not everything is what it appears to be!!

When I get depressed about Mankind’s lack of commitment to follow up on the Apollo moon landings (coming up to 50 years on, sigh) I wonder if we will ever go back and in the future when we train super resolving scopes on the moon and find tracks we might struggle to remember we actually made them.....

Link to comment
Share on other sites

 

It's worth noting that, on the basis of a few spurious scratchy lines, Lowell managed to 'find' enough material for a number of books and to assert that the Martian government would be a right wing Republican one since only such a government would be capable of orchestrating global scale works of civil engineering. Since he was of this political persuasion himself I'm inclined to suspect that he had a significant problem with his ego, though current events might be encouraging this inclination!

Science is a culture of doubt, Lowell's was a culture of certainty.

Olly

PS

8 minutes ago, tomato said:

When I get depressed about Mankind’s lack of commitment to follow up on the Apollo moon landings (coming up to 50 years on, sigh) I wonder if we will ever go back and in the future when we train super resolving scopes on the moon and find tracks we might struggle to remember we actually made them.....

Shades of Planet of the Apes...

Link to comment
Share on other sites

"I've seen them"! He says rather stupidly.

Well I've seen some of the features listed as canali, which are not the canals observed by Lowell. In 2003 I was shocked to notice that some of the features I'd sketched using my Tak FS128 were listed on some charts as being canals. The most obvious was the dark, fine linear feature linking Mare Acidalium in the north with Margaritifer Sinus in the south. The canals name is Indus. Other features easily visible in amateur scopes that were once thought of as canali (channels), and not the Martian made fantasies of good old Percy, can be seen around Solis Lacus where there are several all linking the eye to the surrounding terrain. The one that sticks in my mind most - probably because I like rice pudding -  is named Ambrosia. You can see indications of these in the sketches I made both in 2003 with the FS128 and in 2016 with a FC100DC. Attached!

I've noticed also on numerous occasions that the orcha dust planes are not of even colour, and when the seeing is particularly steady, the edge of one plane where it joins to another of a subtly different shade, can give the illusion of a fine line. This may become even more evident in a much larger refractor such as those used by Schiaparelli, Lowell and the like. Youll need a reasonable image scale to study the dust planes, so powers of X200 to X400 should be used if the seeing allows. In the 8.5" refractor at my local astro club, back in 2003 the dust planes almost gave the impression of a fractured egg shell. Perhaps these colour boundaries, giving the impression of a fracture are partly responsible for the canali hypothesis?

 

20181225_191418.jpg

2018-12-25 19.16.01.jpg

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.