Later the same evening I imaged Jupiter (last post), I also
imaged Mars. The planet is close to the zenith around 9:30 local time here in
Charlotte. Conditions were not as favorable as they were the last time I imaged
the planet (I had to remove heavy dew from the corrector using a hair dryer),
but I was able to capture a usable image using the 5 inch Mak and SLP imager (this is a stack of the best 40% of 15,000 frames).
Looking at the Mars map below the image, it’s not as easy to
align the features with the map as it was in the previous image. Even early
Mars observers noted that dust storms and weather on the Red Planet can make significant
differences to surface features, and this appears to be the case with this image.
Nevertheless, some features identifiable: the north polar
cap, and, at the top of the globe, Mare Sirenium, Mare Cimmerium, and Solis
Lacus. The lighter, circular feature below center left is Amazonis, part of the Tharsis
bulge, with its massive volcanoes, including Olympus Mons, the largest known volcano
in the Solar System. Adjacent lighter areas,A rcadia, and Elysium,
are also visible.
Many of these names originated from the observations of Percival
Lowell. Lowell was a businessman, as well as a brilliant mathematician and avid
astronomer. From 1893 to 1908, he studied Mars from his well-equipped private observatory
in Flagstaff, AZ. Using his 24 inch Alvan Clark and Sons refractor, he noticed
what he called “non-natural features” on the planet—the famous (or infamous)
canals.
Lowell's canal map--1905
Lowell was consumed by the romantic vision of a mighty
civilization struggling to survive as their planet slowly withered around them.
The canals formed a vast transportation network, moving water from the polar regions
to the dry deserts in temperate and equatorial regions. He also gave features
on the planet romantic and evocative names (Arabia, Amazonis, Elysium, etc.),
which created an exotic image of Mars in the popular imagination. The Barsoom
novels of Edgar Rice Burroughs echoed this sentiment, while H.G. Wells explored
its darker side in War of the Worlds.
But even in Lowell’s time, there were many who doubted the
existence of the canals he so carefully mapped. The great astronomer E.M.
Antoniadi reported seeing canals occasionally, but he believed they were an
optical illusion caused by the brain joining up fleeting, fine details into
linear features (I have, myself, seen linear features when visually observing
Mars, only to have them break up into a complex of fine detail in moments of
good seeing). Others criticized the whole idea of using open canals to
transport water as preposterous, as evaporation would consume any water long
before it reached lower latitudes. The overwhelming consensus was that the
Martian climate was too hostile to support the development of complex life forms
such as those Lowell envisaged. But despite this, the idea of a Mars with some
sort of life persisted—I have a 1960s astronomy book which says the scientific
consensus was that the dark areas on the planet were evidence of hardy,
lichen-like plants.
The probe Mariner 4 put the final nail in the coffin of this
belief. Its pictures showed a cratered, dry, moonlike world with an atmosphere
far thinner than had been previously thought. However, these images resulted in
an overcorrection of our perception of Mars. The track of the probe took imaged,
by serendipity, the most moonlike areas of the planet. Future probes, such as
the Viking landers, showed a much more Earth-like planet with bright skies and
a landscape not unlike the US desert southwest.
Now, we know Mars is a dynamic world of winds and storms, of
cratered plains and sand dunes. It is indeed an alien place, but our perception
of it is still colored by the romantic imagination of Percival Lowell.
