Solar & Planetary LtE Now in November 2019
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¤•••••Subject: Early Mars Images.
Here on some early Mars images, taken with an 203mm (8") Newtonian telescope.
Using a ZWO ASI 290mm camera with a proplanet 742 filter and a 2.5X powermate.
These images were taken during daylight hours.
Best to all.
Tim WILSON (
¤•••••Subject: Mars 29 November 2019 0322UT IR
Another early apparition view of Mars in IR and at 3.9". Mare Acidalium is at lower left with Niliacus Lacus just above it. Aurorae Sinus is at upper centre with Mare Erythraeum extending across the upper left limb. The bright Tharsis region covers the right region of the planet.
Best regards, Clyde
¤•••••Subject: Saturn (November 20th.)
A late apparition image from the 20th. Seeing was fair. Probably my last one of this apparition.
Little activity but the polar hexagon is well seen along with the central polar spot.
(Selsey, WS, the
¤•••••Subject: Copernicus (November 6th.)
Here is an image obtained of Copernicus on Nov 6th. Seeing was fair but resolution is very good in places.
1m telescope with ASI174MM.
(Selsey, WS, the
¤•••••Subject: Plato (November 6th.)
Some reasonable seeing for a short time on Nov 6th. No planets were well placed so targeted our nearest neighbour. This view of Plato shows tiny craters down to ~250m in size in some places.
1m telescope with ASI174MM camera.
(Selsey, WS, the
¤•••••Subject: Transit of Mercury
Dear Drs. Murakami and Konnai (and cc: Drs Pasachoff and Schneider),
I managed to get a look at the Moon through the 8-in. reflector, before heading off to Big Bear Solar Observatory in Southern California, where I joined a team led by Jay Pasachoff of Williams College and Glenn Schneider of the University of Arizona to observe the transit of Mercury—especially egress—with the 1.6 meter Goode Solar Telescope. Though the atmospheric conditions were not as good as usual, according to the astronomers who regularly observe with the instrument, because of the adaptive optics of the mirror the images were reasonably sharp—and only a hint of the Black Drop was visible.
That is, of course, because the Black Drop is produced by
softening of the edges of an image owing to diffraction, poor seeing, and (to a
very small extent) limb darkening near the edge of the Sun. See the
diagram below, from Sheehan and Westfall, Transits of Venus (
The subsequent figures show images with the Goode telescope where the Black Drop is not entirely absent but very little in evidence as expected given the conditions of observation, together with an image of Mercury by the limb obtained by an amateur with an 80mm solar telescope, in poor seeing.
Incidentally, it was rather common to see, in books written before the 2004 transit of Venus, that the Black Drop was produced by the atmosphere of Venus, which of course is not the case, since Mercury, which has little atmosphere, also shows a Black Drop, as here. This is an example of how difficult it is to weed out incorrect information from the literature.
PS. I have many fond memories of my visit to
Bill SHEEHAN (
¤•••••Subject: Mars 7 November 2019 0346UT IR
Mars 2020. A rather inauspicious start to what should, hopefully, be another amazing apparition, with Mars growing to 22.6" later in 2020. Although moving north, it should be well placed from my location for me to comprehensively cover the apparition still. Mars will always remain special for me, as it was the planet that started me on my planetary imaging journey.
The IR capture was half an hour after sunrise this morning, at an altitude of 22 degrees in poor seeing, and with the planet at 3.7" in size. Syrtis Major can be made out at upper right and Utopia Planitia in the lower section of the planet.
¤•••••Subject: The reflector assembled
I succeeded in putting together the 8-in. Reflector this weekend, and am going to test it on the Moon as soon as tonight. I must admit that—as with Masatsugu’s observing books—this classic telescope hearkens back to an era that I remember well. It characterized my growing up years (the 1950s and 60s, which I have called the Golden Age of Amateur Astronomy), but many of those who have become involved in amateur astronomy more recently no longer remember any of it.
Stuart Williams, a librarian and archivist of the Society for the History of Astronomy who recently passed away, wrote in 2009: “The Chambers Dictionary defines the term ‘amateur’ as ‘an enthusiast or admirer’; ‘a person who practices something for the love of it, not as a profession;
I paraphrase his further words here: “Astronomy owes much to the amateur, whether they be the wealthy ‘grand amateurs’ of the nineteenth century before the science became a profession, or the ingenious and often quirky amateurs of more recent times. But we are now living in a time when there is a very real need to make the effort to preserve the disappearing world of amateur astronomy. One defined by remarkable ingenuity and the willingness to build complex equipment, especially telescopes, from scratch. A world endangered by a flood of cheap, good quality commercially made telescopes which, while opening astronomy to more people than ever before, offer no incentive to build and experiment.”
The telescope that is here with us now recalls those days when most amateurs
still tried their hand at building a telescope, and still spent time looking at
the detail on the Moon and planets that was just beyond the limit of clear
definition and had to be eked out sometimes with the imagination. There
was something addictive to that study and those who grow up now in the era of
spacecraft imagery, CCDs, and commercially made telescopes cannot know the joy
of it. Sometime I hope to write a history of that era—since I was
privileged to know many of those who were its ablest practitioners. None
contributed more to the classical era of Mars observations, however, than
Masatsugu Minami, who was “Mars-intoxicated” and probably holds the world
record for the most drawings of Mars made using the old visual methods of any
person in history. I am so glad that Lowell Observatory has agreed to
preserve his uniquely valuable records, and hope to include mention of them in
forthcoming works on Mars.
Bill SHEEHAN (
¤•••••Subject: Telescope assembled
Bill SHEEHAN (