Solar
& Planetary LtE Now in November 2019
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necessarily cited in the PDF’s CMO LtE
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¤•••••Subject: Early Mars
Images.
Received:
Hi All,
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
Received:
Hi all,
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.)
Received:
Hi all,
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.
http://www.damianpeach.com/sat19/s2019-11-20-0000_2-RGBdp.jpg
Best
wishes,
Damian PEACH
(Selsey, WS, the
¤•••••Subject: Copernicus
(November 6th.)
Received:
Hi all,
Here is
an image obtained of Copernicus on Nov 6th. Seeing was fair but resolution is
very good in places.
http://www.damianpeach.com/lunar19/copernicus_2019_11_06dp.jpg
1m telescope with ASI174MM.
Best wishes,
Damian PEACH
(Selsey, WS, the
¤•••••Subject: Plato
(November 6th.)
Received:
Hi all,
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.
http://www.damianpeach.com/lunar19/plato_2019_11_06dp.jpg
1m telescope with ASI174MM camera.
Best
wishes,
Damian PEACH
(Selsey, WS, the
¤•••••Subject: Transit of
Mercury
Received:
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.
Best,
Bill
PS. I have many fond memories of my visit to
Bill SHEEHAN (
¤•••••Subject: Mars 7
November 2019 0346UT IR
Received:
Hi all,
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.
Best
regards,
¤•••••Subject: The reflector
assembled
Received:
Dear
friends,
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.
Best, Bill
Bill SHEEHAN (
¤•••••Subject: Telescope
assembled
Received:
Bill SHEEHAN (