Solar
& Planetary LtE Now in April 2024
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¤••••• Subject
: Mars
30 April 0452UT RGB IR
Received:
Hi all,
I had
limited time this morning, and just ran a series of IR captures.
Conditions
were again fairly decent.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240430/CFs30Apr24.png
Best
regards,
¤••••• Subject
: Re: Mars 28 April 0454UT
RGB IR
Received:
Don't
be discouraged by the need to show an IR image only.
Your April
28th image shows an irregularity developing in the South Polar Cap -- it
extends slightly in the direction of Syrtis Major.
This is
consistent with the "Mountains of Mitchel", the first showing of them
this apparition.
Pretty
good for low altitude and only 4.7 arc seconds in diameter!
Roger
Roger VENABLE (
¤••••• Subject
: Mars
29 April 0443UT RGB IR
Received:
Hi all,
Another morning of some nice seeing conditions.
A
surprisingly difficult process, due to the brightness of the SPC and I wasn’t
totally successful in preventing saturation.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240429/CFs29Apr24.png
Best
regards,
¤••••• Subject
: The
colors of Saturn in 2023-22 (II) North-Souths scans
Received: 28 April 2024, 23:06 JST
Hi all here
are the next results of the Saturn study.
Polar
scans are scaled by calculating the albedo of the southern part of the
equatorial zone (same method than for Jupiter). I have calculated the scans for
2022 as well, and scaled them with the same value of albedo for the EZs, since
I think it may not have changed in just one year ; the method have its limits
but I did not made photometry in 2022.
With
the approach of the equinoxe, we expect to see the southern hemisphere
brighten, and the northen one dim. This is indeed what
can be seen in red light. However, in blue light, BOTH hemispheres have dimmed,
which explains why it lost its noticeable blue tint of 2021-2022. In the other
hand, the south hemisphere looks to have brightened noticeably in visible/green
light, which explains why the overall southern tint turned to a pale green in
2023!
More
suprising however are the results in infrared, that
may show a noticeable dimming of the north hemisphere in the I band, and a
dimming of the whole globe in CH4! This may be an uncorrect result due to the
fact that I did not make photometry in 2022, however, when I look at images I
do feel that it is true.
Do we
have more data about this from HST or other ?
For the
next set, I will introduce analysis of color indices, and I will talk about the
rings later.
Best
wishes,
Christophe
Christophe PELLIER (
Planetary astronomy and imaging
¤••••• Subject
: Mars
28 April 0454UT RGB IR
Received:
Hi all,
I had
just a short period of clearing between clouds this morning where I was able to
run a short IR series of captures. Seeing was not particularly good as the
cloud moved back in.
The image
is centred near Margaritifer S with M Erythraeum dominating towards upper
right.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240428/CFs28Apr24.png
Best
regards,
¤••••• Subject
: Mars
26 April 0508UT RGB IR
Received:
Hi all,
The
seeing conditions deteriorated dramatically towards the end of my Saturn
session, preventing any decent Mars RGB, and it was only just before closing
the observatory, that I had a short reasonable period of IR captures.
Looking down on M Erythraeum, with Aurorae S lower right of
centre and Solis L at upper right. Niliacus L is at lower centre, with
Nilokeras to its right. The western section of
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240426/CFs26Apr24.png
Best
regards,
¤••••• Subject
: Mars 25 April 0506UT RGB
IR
Received:
Hi all,
A difficult session this morning with generally poor to very
poor conditions with limited unusable data.
In the
circumstances the IR and R did not come out too badly.
Solis L
is at upper right and M Erythraeum and Argyre are at upper left.
Aurorae
S is just below centre, with Nilokeras at lower centre.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240425/CFs25Apr24.png
Best
regards,
¤••••• Subject
: Mars 24 April 0501UT RGB
IR
Received:
Hi all,
Seeing
varied dramatically from excellent to very poor this morning.
Unfortunately
the very poor conditions coincided with the G and B captures, so I had little
good data to work with.
M. Erythraeum
coming into view at upper left. Ophir,
to the right of Aurorae Sinus, shows as normally bright.
The
region to the upper left of AS shows as light, but I cannot say if this is
unusually so.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240424/CFs24Apr24.png
Best
regards,
¤••••• Subject
: Mars 23 April 0454UT RGB
IR
Received:
Hi all,
Conditions
were not as good this morning.
Solis
Lacus, Valles Marineris and Aurorae Sinus are again the main features.
The
planet appears fairly settled at this stage.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240423/CFs23Apr24.png
Best
regards,
¤••••• Subject
: Mars 22 April 0501UT RGB
IR
Received:
Hi all,
Another
very pleasant morning in the observatory, and although conditions did vary,
there were quite a few periods of very good seeing.
Solis
Lacus and Valles Marineris are the dominant features near centre, with Aurorae
Sinus noticeable to the left.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240422/CFs22Apr24.png
Best
regards,
¤••••• Subject : Mars 21 April
0458UT RGB IR
Received:
Hi all,
Image
set this morning, looking down on Solis Lacus and Valles Marineris. No obvious cloud over the Tharsis region.
It was
a pleasure to have Dr Christiaan Brinkerink of
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240421/CFs21Apr24.png
Best
regards,
¤••••• Subject : Mars 20 April
0502UT RGB IR
Received:
Hi all,
I again
had some decent seeing for Mars this morning after it had taken a dip during my
Saturn session.
Solis
Lacus shows nicely upper left of centre with Valles Marineris below it.
I have
been committing more time to the B captures (my thanks to Damian Peach…),
although I do not detect any cloud over the Tharsis Montes.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240420/CFs20Apr24.png
Best
regards,
¤••••• Subject : Mars 18 April
0509UT RGB IR
Received:
Hi all,
Catching up with my Mars images from yesterday morning, as I
had to go into
M
Sirenum is at upper right, with Solis Lacus at upper left and the Valles
Marineris complex extending in from centre left. Olympus Mons is at lower
right.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240418/CFs18Apr24.png
Best
regards,
¤••••• Subject : Mars 19 April
0511UT RGB IR
Received:
Hi all,
Seeing
recovered towards sunrise for this Mars image set.
M
Sirenum is at upper right , with Solis Lacus at upper
left and the Valles Marineris complex extending in from centre left. Olympus
Mons is at lower right.
The B
data was not bad, and I see no indication of any cloud over Arsia Mons.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240419/CFs19Apr24.png
Best
regards,
¤••••• Subject : Re: Mars 15 April
0507UT RGB IR
Received:
I agree with your interpretation of your April 15th image,
Clyde.
It will be interesting to see how these features persist in the coming months.
--
Roger
Roger VENABLE (ALPO:
¤••••• Subject EPSC2024 - submit your
abstract to the pro-am collaboration session!
Received:
Dears,
The European Planetary Science Congress 2024 full
hybrid conference will be held this year in
Please
consider submitting abstracts on any pro-am topic
in planetary science (planets, small bodies, exoplanets, ...) in the ODAA1 dedicated pro-am session before
May 15th, 13:00 CEST.
Please
note that there is an abstract submission fee of
50€ and
that you can apply to a bursary
Feel free
to circulate this message to all those who might be interested in this event.
Looking forward reading your abstracts,
M.
Delcroix, R. Hueso, F. Libotte, J. Rogers, E. Podlewa-Gaca
Marc DELCROIX (
¤••••• Subject : Mars 16 April
0502UT RGB IR
Received:
Hi all,
Image
set from this morning. Conditions had been very nice earlier for Saturn but did
deteriorate a bit for this session.
I did try
a technique recommended by Damian Peach for distant Mars captures, namely using
a synthetic G generated from the R and B images. Any failure in the application
of the technique is purely on my part!
M
Sirenum remains the dominant feature above centre.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240416/CFs16Apr24.png
Best
regards,
¤••••• Subject : Mars 15 April
0507UT RGB IR
Received:
Hi all,
I had a deterioration in seeing during
the Mars session this morning, with the G and B being particularly negatively
affected. I was limited to using the single best G and B for the RGB.
It is interesting
to compare (the R in particular) with the Adachi ALPO-Japan Maps around the M
Sirenum region, notably the “arm” (unnamed) extending above M Sirenum and
Sirenum D, with a dark feature at its end.
I also
think
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240415/CFs15Apr24.png
Best
regards,
¤••••• Subject : Re: The colors of Saturn in 2023 (1) Photometry and images
Received:
Thanks,
Christophe.
Best
regards and wishing you clear steady skies,
Julius
Julius
L. BENTON (
¤••••• Subject : Mars 14
April 0458UT RGB IR
Received:
Hi all,
A
rather rushed Mars session this morning as the sky was brightening.
I was
only able to capture single usable G and B’s, and I wasn’t particularly happy
with the RGB. The IR was best.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240414/CFs14Apr24.png
Best
regards,
¤••••• Subject : The colors
of Saturn in 2023 (1) Photometry and images
Received:
Hi all,
It's
been two years now that I am able to make a photometric study of Jupiter, and
here you will find my first one on Saturn :)
The
data has been obtained on two nights from last september
although I have also partially used the data gathered in August at the
AstroQueyras Observatory.
In
comparison with Jupiter, the difficulty of Saturn comes from the rings that
almost always partially mask the globe. I have dedicated much time to read some
scientific litterature in the hope of finding equations to deal with this
problem but I didn't find how to do this. However, since I am working on disk
resolved images, it is then possible to isolate the globe from the adjacent
rings, letting only the part that passes in front of the disk. This is not a
problem for the photometric calibration, in that case
the frontal rings are just considered as a particular "banding
domain". However, it make comparison with
historical references less accurate.
The
values found are none the less right on track of the expected values from U to
V. They are lower in R and IR, but this would easily comes from the fact that Saturn
is approaching equinox, and the globe is getting less red, and less bright,
during the process - values in R and IR are getting closer to the Karkoschka's
spectrum that has been made in 1995 right when Saturn was at equinox. The
albedo of 12% in CH4 is obviously affected by the bright rings.
I am
adding comparisons of images from 2022 but I did not make a photometric
calibration back then.
As for
Mars, the calibration of the B425 filter is obtained through homemade
magnitudes calculated from spectroscopy and looks also correct.
In the
second message (probably next week-end) I will send photometric profiles from
north to south, to evaluate some of the color changes from 2022 to 2023, and in
a third one we will talk about the rings themselves.
Have a
nice week-end,
Christophe
Christophe PELLIER (
Planetary astronomy and imaging
¤••••• Subject : Mars 11
April 0419UT RGB IR
Received:
Hi all,
If
nothing else, I am finding fairly consistent and reasonable seeing conditions
over the last few mornings.
M
Sirenum is above left of centre, and M Cimmerium above right of centre.
Phaethontis,
Electris and Eridania are above them.
Amazonis
dominates the lower section of the planet. Possibly a hint of
some cloud in the north.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240411/CFs11Apr24.png
Best
regards,
¤••••• Subject : Mars 10
April 0422UT RGB IR
Received:
Hi all,
Image
set from this morning. Jetstream was still strong, but again I found reasonable
seeing towards sunrise.
M
Cimmerium at upper right of centre and M Sirenum coming into view at upper left
of centre.
Amazonis
extends across the lower section of the planet.
In the
IR and R, I think I may have detected the rift in the SPC.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240410/CFs10Apr24.png
Best
regards,
¤••••• Subject : Mars 9
April 0425UT RGB IR
Received:
Hi all,
Given
that there was a strong Jetstream overhead, and a gusting 2-3m/s wind at the
observatory, conditions were surprisingly good this morning.
M
Cimmerium is the dominant feature, with Elysium at lower right, possibly with
some cloud?
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240409/CFs09Apr24.png
Best
regards,
¤••••• Subject : Mars
2024-04-08
Received:
Mars images on
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240408/Ak08Apr24.png
Best
regards,
Tomio AKUTSU (
¤••••• Subject : Saturn 2024-04-08
Received:
Saturn image on
Best
regards,
Tomio AKUTSU (
¤••••• Subject : Mars
2024-04-06
Received:
Mars image on
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240406/Ak06Apr24.png
Best
regards,
Tomio AKUTSU (
¤••••• Subject : Saturn 2024-04-06
Received:
Saturn image on
Best
regards,
Tomio AKUTSU (
¤••••• Subject : Mars 6
April 0424UT RGB IR
Received:
Hi all,
Conditions
improved somewhat towards sunrise to allow this set. I am noticing the
jetstream is starting to increase.
The
main features visible are M Cimmerium (L), Hesperia (light ,
centre) and M Tyrrhenum (R) .
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240406/CFs06Apr24.png
Best
regards,
¤••••• Subject : Saturn 2024-03-29
Received:
Saturn images on
Best
regards,
Tomio AKUTSU (
¤••••• Subject : Mars
10. 12. 15. 28 and 29 March 2024
Received:
Mars images on 10. 12. 15. 28
and 29 March 2024 UT.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240329/Ak29Mar24.png
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240328/Ak28Mar24.png
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240315/Ak15Mar24.png
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240312/Ak12Mar24.png
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240310/Ak10Mar24.png
Best
regards,
Tomio AKUTSU (
¤••••• Subject : Mars
observations - 21 and 26 March 2024
Received:
Good
morning, circulating my recent Mars captures from
Thanks
very much to Clyde Foster for sharing the above emails.
I
normally only publish on Facebook and AstroBin at Seb Lukas's gallery - AstroBin.
Hope
the work will be of interest to researchers.
Caption
for 21 March - Red Planet half an hour after sunrise on
The
image is centered on longitude 265 with Mare Tyrrhenum and Syrtis Minor
crossing the terminator. Syrtis Major is rising in the west,
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240321/SLk21Mar24.png
Caption
for 26 March - Mars in dawn sky on
Another capture of the Red Planet following sunrise. Elevation and angular size identical to the last image, background
slightly darker due to a longer night. This view is centered on
longitude 215 with Mare Cimmerium on the terminator, Mare Tyrrhenum immediately
to its west. Resolution is good enough to detect the
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240326/SLk26Mar24.png
Regards,
Seb
Lukas
Sebastian LUKAS (
Seb Lukas's gallery - AstroBin.
¤••••• Subject : Mars 2
April 0421UT RGB IR
Received:
Hi all,
A brief session on Mars this morning as I wanted to allocate
a bit more time to Saturn.
There
is maybe a hint of light cloud in the north that may extend over the
Perseverance rover region.
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240402/CFs02Apr24.png
Best
regards,
¤••••• Subject : Mars 1
April 0437UT RGB IR
Received:
Hi all,
A
rather soft image set from this morning, again looking down on Syrtis Major and
But
hopefully good enough to confirm that the atmosphere is fairly clear at this
point.
Maybe a bit of brightening in
https://www.kwasan.kyoto-u.ac.jp/~cmo/cmons/2024/240401/CFs01Apr24.png
Best
regards,