Last night had very good conditions, and I finished off the Carbon Star list using the 8-inch. I hate to say but this one seemed like a chore -- perhaps because its documentation requirements were more stringent than others? But the stars are very pretty, and I hope I'll remain sensitive to seeing them:
S Scuti: Beautiful orange, brightest in the field, but some in field are nearly as bright. Close double to SE. Rich field.
UX Draconis: Bright orange, brightest in a poor field; forms a triangle with other stars.
I needed to use the Vixen wide field binoculars to find both stars -- it helps reveal all a constellation's brighter stars so it looks closer to an atlas view for better orientation. UX Draconis by first finding Polaris, then Ursa Minor, then finding the odd trapezoid pattern of stars in the curve of the Dragon; from there it was an easy Quickfinder find to the correct field.
S Scuti was a little more effort. I knew it was nearby to M11 the Wild Duck Cluster, and I was going to wait until it had risen above the neighbor's tree. But then I saw Altair rising above the roof and I used the binoculars to follow Aquila's stars down to its lower three stars which form a swooping pattern toward M11. I moved the scope to the right spot in the yard to view and again, M11 was an easy find. It was a profusion of faint stars separated by gaps. A bright star in the eastern portion of the spray, with stars raining down from it toward the west. It looked like the tip of an arc welder with sparks spraying out and down from it, scattering and extinguishing in the sky. This was the first I've seen of M11 in a couple years and it was magnificent.
I had the usual views of Jupiter, Mars, and Saturn, all very satisfying. A good evening.
Monday, June 27, 2016
Sunday, June 26, 2016
a couple good nights
Thursday and Friday nights turned out very well. I observed with the 8-inch and gained some traction on the Stellar Evolution and Carbon Star lists -- a nice feeling to make progress.
Both nights featured views of Jupiter, Mars, and Saturn during the astronomical twilight. Thursday features a GRS transit of Jupiter; it seems to ride on the SWB. Saturn's Cassini division was well seen, along with four moons each night. Thursday was cut short by marine layer. Some scraps of it started to fly through Scorpius so I changed observe in Lyra and Hercules. I was just about to make my observation of AC Herculis after a long hop from Beta Lyrae, and after checking the chart looked back in the eyepiece and found it totally clouded out. Otherwise, very good conditions. All observations at 184x. I had a couple non-list observations, too:
Gliese 581 = HO Lib, red dwarf in Libra: Small, faint, slightly red. 20 light years away, a red dwarf with 4 or more planets, intensively studied for habitable planets. Has a debris disk providing 10x the comets as our system
18 Scorpius: Unremarkable yellow-white star. 45.3 light years distant, shares many characteristics with sun. Good candidate for hosting planets with life, but none yet discovered
Antares = Alpha Scorpius: Bright shimmering red-orange. No companion seen. Red giant; one of the largest and brightest observable stars; 883x radius of Sun.
Zeta Ophiuchi: Pretty, brilliant white star. Aged only 3m years, but will expand to red giant in a few million years and go supernova. It has high velocity and NASA has imaged it creating a bow shock in an interstellar dust cloud
Rasalgethi = Alpha Herculis: Beautiful orange yellow A with a closely split much fainter greenish B. A is a asymptotic giant branch star, with both helium and hydrogen shells around a degenerate carbon-oxygen core. 400x the sun, it is experiencing rapid mass loss. B has its own pair, not seen
Barnard's Star = HIP87937: ordinary, faint, slightly red. Low mass red dwarf 6 light years from earth. EE Barnard measured its proper motion as 10.3" per year. 7-12 billion light years old, among the oldest in the Milky Way.
Vega = Alpha Lyrae: Brilliant white; said to be a double. 25 light years away; was the northern pole star in 12,000 BC. 1/10th the age of the sun but will only live 1/10th the time; it will become a planetary nebula in about 500 million years.
RR Lyrae: ordinary, 8-9th magnitude, a little yellow-white. Brightest of its type of variable stars which serve as standard candles to measure stellar distances
Albireo = Beta Cygni: Astonishingly beautiful gold (A) and blue (B), in a rich field of stars. First view this season, wow. 430 light years distant; 35" separation; not known if physical pair. A has a confirmed 0.4" pair, too close to see.
Sigma Draconis: Pretty yellow-white. 18.8 light years away, has a high proper motion of 1.825" per year.
Altair = Alpha Aquilae: very bright brilliant white. 16.7 light years distant. Rotates very rapidly, more than half its break-up speed, bulging its equator. It is a multiple system with four components, two of which are gravitationally bound to A; I didn't notice any of them.
η Eta Aqlilae: Light yellow ordinary star. Cepheid variable, ranges from 3.5 to 4.3 over 7.17 days -- have to watch this one!
Epsilon Draconis: Very pretty bright yellow A and ~4 magnitudes fainter, close but split white B. Probably an optical pairing. 3.2" separation 4.0 mag A, 6.9 B
K Draconis: Bright white with a dim yellow B, large magnitude difference, well split.
V Ophiuchi: carbon star: Very red, fairly bright; seen in finder. Est. 8.0 C6 [AAVSO 7.5, C5-7]
TW Ophiuchi: carbon star: Very deep orange; makes a triangle with other stars but otherwise a star poor area. Est. 7.0, C5. AAVSO N/A C5
SZ Sagittarii, carbon star: Faint red-to-orange in a string of four stars -- also makes a triangle with other stars. Est. 8.5, C6. AAVSO N/A, C7
FO Serpentis, carbon star: Very faint, whitish yellow In a wide triangle of brighter stars. Est. 8.5, C2 [AAVSO N/A, 8.5-8.7, C4]
AC Herculis, carbon star: Very faint, white with a little orange. Est. 6.0 C1 [AAVSO 7.5 6/20/16, C0)
I thought I was finished with the carbon star list, but after sorting out my file today find I have two I thought I observed but for which I don't have the documentation. They are both up in the sky now, so I should be able to finish the list, maybe tonight.
Both nights featured views of Jupiter, Mars, and Saturn during the astronomical twilight. Thursday features a GRS transit of Jupiter; it seems to ride on the SWB. Saturn's Cassini division was well seen, along with four moons each night. Thursday was cut short by marine layer. Some scraps of it started to fly through Scorpius so I changed observe in Lyra and Hercules. I was just about to make my observation of AC Herculis after a long hop from Beta Lyrae, and after checking the chart looked back in the eyepiece and found it totally clouded out. Otherwise, very good conditions. All observations at 184x. I had a couple non-list observations, too:
Gliese 581 = HO Lib, red dwarf in Libra: Small, faint, slightly red. 20 light years away, a red dwarf with 4 or more planets, intensively studied for habitable planets. Has a debris disk providing 10x the comets as our system
18 Scorpius: Unremarkable yellow-white star. 45.3 light years distant, shares many characteristics with sun. Good candidate for hosting planets with life, but none yet discovered
Antares = Alpha Scorpius: Bright shimmering red-orange. No companion seen. Red giant; one of the largest and brightest observable stars; 883x radius of Sun.
Zeta Ophiuchi: Pretty, brilliant white star. Aged only 3m years, but will expand to red giant in a few million years and go supernova. It has high velocity and NASA has imaged it creating a bow shock in an interstellar dust cloud
Rasalgethi = Alpha Herculis: Beautiful orange yellow A with a closely split much fainter greenish B. A is a asymptotic giant branch star, with both helium and hydrogen shells around a degenerate carbon-oxygen core. 400x the sun, it is experiencing rapid mass loss. B has its own pair, not seen
Barnard's Star = HIP87937: ordinary, faint, slightly red. Low mass red dwarf 6 light years from earth. EE Barnard measured its proper motion as 10.3" per year. 7-12 billion light years old, among the oldest in the Milky Way.
Vega = Alpha Lyrae: Brilliant white; said to be a double. 25 light years away; was the northern pole star in 12,000 BC. 1/10th the age of the sun but will only live 1/10th the time; it will become a planetary nebula in about 500 million years.
RR Lyrae: ordinary, 8-9th magnitude, a little yellow-white. Brightest of its type of variable stars which serve as standard candles to measure stellar distances
Albireo = Beta Cygni: Astonishingly beautiful gold (A) and blue (B), in a rich field of stars. First view this season, wow. 430 light years distant; 35" separation; not known if physical pair. A has a confirmed 0.4" pair, too close to see.
Sigma Draconis: Pretty yellow-white. 18.8 light years away, has a high proper motion of 1.825" per year.
Altair = Alpha Aquilae: very bright brilliant white. 16.7 light years distant. Rotates very rapidly, more than half its break-up speed, bulging its equator. It is a multiple system with four components, two of which are gravitationally bound to A; I didn't notice any of them.
η Eta Aqlilae: Light yellow ordinary star. Cepheid variable, ranges from 3.5 to 4.3 over 7.17 days -- have to watch this one!
Epsilon Draconis: Very pretty bright yellow A and ~4 magnitudes fainter, close but split white B. Probably an optical pairing. 3.2" separation 4.0 mag A, 6.9 B
K Draconis: Bright white with a dim yellow B, large magnitude difference, well split.
V Ophiuchi: carbon star: Very red, fairly bright; seen in finder. Est. 8.0 C6 [AAVSO 7.5, C5-7]
TW Ophiuchi: carbon star: Very deep orange; makes a triangle with other stars but otherwise a star poor area. Est. 7.0, C5. AAVSO N/A C5
SZ Sagittarii, carbon star: Faint red-to-orange in a string of four stars -- also makes a triangle with other stars. Est. 8.5, C6. AAVSO N/A, C7
FO Serpentis, carbon star: Very faint, whitish yellow In a wide triangle of brighter stars. Est. 8.5, C2 [AAVSO N/A, 8.5-8.7, C4]
AC Herculis, carbon star: Very faint, white with a little orange. Est. 6.0 C1 [AAVSO 7.5 6/20/16, C0)
I thought I was finished with the carbon star list, but after sorting out my file today find I have two I thought I observed but for which I don't have the documentation. They are both up in the sky now, so I should be able to finish the list, maybe tonight.
Thursday, June 23, 2016
frustrating night
Last night was very frustrating. I had cooled the 12.5-inch as I usually do and started observing after dark. But the seeing was atrocious. I could not form clean images on anything, even as low as 170x. I started with Jupiter, then Mars. Through the murk and haze I was able to see Syrtis Major, Sinus Sabaeus, Sinus Meridiani, and so on. But it was very poor. I tried different solutions but only the apodising screen seemed to help, but little. There must've been some seriously bad roof currents, and general heat dissipation from the ground. At 9:40pm I turned my scope back to Jupiter to watch Io reemerge from the planet's shadow; the ephemeris or my watch may have been off since Io was already there -- it wasn't supposed to appear until 9:44pm. I thought perhaps the seeing would be better at zenith, so I tried Cor Caroli -- but it was horribly smeared. I checked the primary mirror to see if it was dewed, or if collimation had somehow gotten way off -- but nether was the case. So I packed it in early, and just had some simple naked eye viewing.
I suppose the only solution to suburban summer viewing is to get up early; it's the only chance for the local seeing to be somewhat settled. It was a frustrating night, but I'm not upset about it -- you just have to take what the sky gives you.
I suppose the only solution to suburban summer viewing is to get up early; it's the only chance for the local seeing to be somewhat settled. It was a frustrating night, but I'm not upset about it -- you just have to take what the sky gives you.
Wednesday, June 22, 2016
jupiter and mars
Had a session last night using the 12.5-inch, but was disappointed with the seeing. Very watery and difficult to hold detail. I think the upper atmosphere was fine, but near the ground there was a lot of turbulence due to the temperature swing from the 90s to the 60s after dark -- too much heat being released by houses, streets, and the ground. Tonight's forecast is much the same, with great transparency and good seeing -- it's not as hot today so perhaps it will be better.
I only made two observations, Jupiter and Mars. Io had just started a transit when I began a little after 9pm, but I could not see its disk despite being at 340x (and the planetary filter & apodising screen). Not like Fremont Peak last month with the 20-inch, where we tracked Io as long as we wanted. My sketch reveals some largish festoons in the central band, but nothing remarkable. I observed Mars for a while then turned back to Jupiter at around 10:15pm to see Io's shadow, a very small round black dot on the NEB. Always nice to see a shadow transit; Jupiter is getting pretty low so there won't be many chances.
Mars looked better, using the same set-up. Syrtis Major was a prominently dark triangle near the western limb. I also observed the lighter sweeps of Sinus Sabaeus, Sinus Meridiani, and the beginnings of Mare Acidalium. Arabia was a clean clear orange color, with Eden pointed directly at me from the center.
I only made two observations, Jupiter and Mars. Io had just started a transit when I began a little after 9pm, but I could not see its disk despite being at 340x (and the planetary filter & apodising screen). Not like Fremont Peak last month with the 20-inch, where we tracked Io as long as we wanted. My sketch reveals some largish festoons in the central band, but nothing remarkable. I observed Mars for a while then turned back to Jupiter at around 10:15pm to see Io's shadow, a very small round black dot on the NEB. Always nice to see a shadow transit; Jupiter is getting pretty low so there won't be many chances.
Mars looked better, using the same set-up. Syrtis Major was a prominently dark triangle near the western limb. I also observed the lighter sweeps of Sinus Sabaeus, Sinus Meridiani, and the beginnings of Mare Acidalium. Arabia was a clean clear orange color, with Eden pointed directly at me from the center.
Tuesday, June 21, 2016
full moon
Yesterday evening Carol asked when the moon was to rise. I pointed it out over the East Bay hills when we were driving home from a party Sunday night. She wanted to see it again. So we went for a walk out to a nearby levee trail which had clear views to the west. No moon, it was still too early. I promised I'd look at it at night.
While reclining on the couch reading before bedtime, the moon shown down through a gap in the window and reminded me of my promise. I stepped out onto the back patio and saw a wonderfully transparent night with some altocumulus bands illuminated silver by the moonlight. I grabbed my 7x35 binoculars for a closer look. Scoprius was standing on it's tail, with just the lower curve blocked by a neighbor's house. Mars and Antares were brilliant red. The clouds moved and changed shape imperceptibly: I'd look for a while tracing the glowing broken shoals, then coming back notice they had been transformed. One small cloud had a wavy pattern to it, like sand ribbed by slow shallow surf. That apparition lasted for about 10 minutes. The moon itself rode placidly above the scene.
I dutifully reported what I observed to Carol this morning, and she was very pleased by it.
While reclining on the couch reading before bedtime, the moon shown down through a gap in the window and reminded me of my promise. I stepped out onto the back patio and saw a wonderfully transparent night with some altocumulus bands illuminated silver by the moonlight. I grabbed my 7x35 binoculars for a closer look. Scoprius was standing on it's tail, with just the lower curve blocked by a neighbor's house. Mars and Antares were brilliant red. The clouds moved and changed shape imperceptibly: I'd look for a while tracing the glowing broken shoals, then coming back notice they had been transformed. One small cloud had a wavy pattern to it, like sand ribbed by slow shallow surf. That apparition lasted for about 10 minutes. The moon itself rode placidly above the scene.
I dutifully reported what I observed to Carol this morning, and she was very pleased by it.
Sunday, June 19, 2016
father's day eve observing
Last night I repeated some of the observations of Thursday night, but the seeing was rather worse. We were having a camp-out in the backyard so I was somewhat distracted, too.
Jupiter at 340x was a little mushy. The GRS was nearly midway through transit, and I could clearly see two thirds of the oval were darkened. There was a surprisingly dark medium size lenticular barge in the NEB nearly below the GRS's position. Preceding it was a bright oval on the northern edge of the belt.
I tried the same series of Virgo doubles as Thursday but without any more success. The moon was nearly full and the transparency spread its light across the sky -- so I had little hope of seeing the very faint pairs. I experimented with the 5-inch off-axis mask: it really helped steady the star images and made very nice tight Airy disks, but it also hurt resolution so that the fainter stars were more difficult. I suppose it is best used for tight pairs of similar magnitude.
I observed Mars for a while, at 340x with the apodising screen and planetary filter. By now the seeing was a little better and I saw about as much detail as Thursday, of the same features, but with the planet rotated a little to the east.
As I was staying out a little longer, past 11pm, Antares and Saturn cleared the tree. While the seeing was not great I gave Antares a try. The apodising screen steadied the seeing but the star was a little jumpy. I tried the off-axis mask and it helped to better steady the star; but still no companion star. Finally I used a blue filter with the off-axis mask, and all the diffraction disappeared. It was spooky how it did that. After a while I could discern a very faint concentration -- it wasn't really a stellar point -- to the WNW fairly close to the star. I suppose it was the "B", which is in 277 degree PA now and 2.59" separated. I'll call it a possible sighting, but I'm not particularly confident about it. However, I am impressed with off-axis masks and will make one for my 20-inch to play around with. With the 20-inch's focal ratio, an 8-inch mask will be f/14!
Finally I observed Saturn. It was best with the apodising screen and with my boundary layer fan on -- Cassini division and Enke's minima, and some darkening in the D ring. Lots of color in the planet.
I might not have the opportunity to observe tonight, but Monday is predicted to be above average for seeing and transparency, so I'm hopeful for better views to come.
Jupiter at 340x was a little mushy. The GRS was nearly midway through transit, and I could clearly see two thirds of the oval were darkened. There was a surprisingly dark medium size lenticular barge in the NEB nearly below the GRS's position. Preceding it was a bright oval on the northern edge of the belt.
I tried the same series of Virgo doubles as Thursday but without any more success. The moon was nearly full and the transparency spread its light across the sky -- so I had little hope of seeing the very faint pairs. I experimented with the 5-inch off-axis mask: it really helped steady the star images and made very nice tight Airy disks, but it also hurt resolution so that the fainter stars were more difficult. I suppose it is best used for tight pairs of similar magnitude.
I observed Mars for a while, at 340x with the apodising screen and planetary filter. By now the seeing was a little better and I saw about as much detail as Thursday, of the same features, but with the planet rotated a little to the east.
As I was staying out a little longer, past 11pm, Antares and Saturn cleared the tree. While the seeing was not great I gave Antares a try. The apodising screen steadied the seeing but the star was a little jumpy. I tried the off-axis mask and it helped to better steady the star; but still no companion star. Finally I used a blue filter with the off-axis mask, and all the diffraction disappeared. It was spooky how it did that. After a while I could discern a very faint concentration -- it wasn't really a stellar point -- to the WNW fairly close to the star. I suppose it was the "B", which is in 277 degree PA now and 2.59" separated. I'll call it a possible sighting, but I'm not particularly confident about it. However, I am impressed with off-axis masks and will make one for my 20-inch to play around with. With the 20-inch's focal ratio, an 8-inch mask will be f/14!
Finally I observed Saturn. It was best with the apodising screen and with my boundary layer fan on -- Cassini division and Enke's minima, and some darkening in the D ring. Lots of color in the planet.
I might not have the opportunity to observe tonight, but Monday is predicted to be above average for seeing and transparency, so I'm hopeful for better views to come.
Saturday, June 18, 2016
missed multiples, made up for with mars
Thursday night was predicted to have poor transparency, but fortunately that did not materialize. I started out observing Jupiter during the twilight. At 340x I saw the usual dark barges in the equatorial bands, the one in the southern very long and tapering at the tips like a lenticular galaxy. The GRS was nearly finished with its transit and there was a dark forking barge following it, along with two lighter ovals -- first time I recall seeing such a feature. The barge had swells in them as they extended under the GRS. There was even a barge in the SSTB -- though the whole South Temperate and South Polar region appeared uniform in color. The North Tropical zone was distinct from the Temperate and Polar zones, but these were also a mild uniform color. I'll have to look for separations in these zones in the time remaining this season.
While waiting for the moon and Mars to clear the neighbor's tree, I viewed some doubles in Virgo at 340x; seeing was about Pickering 7:
Rst 3829 / Sh 162: This is a quadruple system with three visible; but I only noted two stars, AB, a widely separated yellow A and orange B, 1 magnitude difference. The Aa Ab system is 0.6 separation, and the BC system has a wide magnitude difference (C is 13.34) which I didn't notice. That's what I get for randomly observing things without research beforehand...
86 Virginis; Stelle Doppie says this is also a quadruple system, and all four should be visible. Again I only noted two, a brighter A and very faint / almost averted vision B widely separated. What I saw was actually the AC pairing, with mag 5.66 A and 11.9 C, 27.3" separation. The AB is 1.2" separation and 5.66 A & 8.47 B. The CD pair is 11.90 and 13.10, 2.4" separation -- I should have noticed a nearby "double double" but did not. I will need to go back...
81 Virginis: I saw a well split close pair of yellow stars about equal magnitude (2.7" 7.79 A & 8.08 B). Unfortunately, this is a triple system with three visible! Missed again! I saw the AB pair but AC is quite widely separated at 137" and a much fainter C at 12.28.
72 Virginis: Bright A and very faint B, widely separated. Luckily this is correct; A 6.14 separated by 29" to 10.74 mag B
STF1775: The losing streak continued: I observed a pretty pairing of a bright orange A and a faint bluish B widely separated. This is probably the AB pair, 27.7" separated and 7.21 mag vs. 10.06. The AC, not noticed, is 38.6" and 14.16 mag.
STF1788: And I closed with a total failure: This is a quintuple system and all 5 are visible. I saw a bright pair of near equal magnitude, both yellow-while color. This is the AB pair. I give you the Stelle Doppie link so you can see how inattentive I was: http://stelledoppie.goaction.it/index2.php?iddoppia=58333
The double session was impromptu, so perhaps I shouldn't be so hard on myself. But, knowing what I can & should see I will retry them the next opportunity.
Mars was now clear of the tree. Seeing had become considerably better, Pickering 8 or 9 -- all the air around me had become still, and the usual loud white noise from the highway was greatly diminished. I pulled out all the stops, as it were: 553x, planetary filter, and apodising screen. It was my best view I've had through my own scope yet, and approaching the very brief look I had through the 36-inch Great Refractor at Lick Observatory about 15 years ago.
Sinus Miridion reached down in a triangular form, with Sinus Sabaeus as a dark barge to the east. The rest of Mare Erythraeum was a dark but somewhat greyish mass covering the rest of the hemisphere; could there have been clouds making the greyish color come out? I noticed two small bright ovals to the west of Margatitifer Sinus but can't account for what it was. Mare Acidalium was a large thick crescent, and I could see the bulge coming out of it to the east, along with some mottling in the brighter plain to the southeast. The southern rim was bright with what could be clouds.
I now understand why observers become so excited during a Mars opposition: with the planet so much closer it offers up a lot more detail. Lin came out for a look and said it looked like the moon -- all the mare visible. I had planned to observe the moon's terminator that night too, but with Mars the way it was I decided to stay on it until bedtime; I can see the moon any month, but not Mars.
While waiting for the moon and Mars to clear the neighbor's tree, I viewed some doubles in Virgo at 340x; seeing was about Pickering 7:
Rst 3829 / Sh 162: This is a quadruple system with three visible; but I only noted two stars, AB, a widely separated yellow A and orange B, 1 magnitude difference. The Aa Ab system is 0.6 separation, and the BC system has a wide magnitude difference (C is 13.34) which I didn't notice. That's what I get for randomly observing things without research beforehand...
86 Virginis; Stelle Doppie says this is also a quadruple system, and all four should be visible. Again I only noted two, a brighter A and very faint / almost averted vision B widely separated. What I saw was actually the AC pairing, with mag 5.66 A and 11.9 C, 27.3" separation. The AB is 1.2" separation and 5.66 A & 8.47 B. The CD pair is 11.90 and 13.10, 2.4" separation -- I should have noticed a nearby "double double" but did not. I will need to go back...
81 Virginis: I saw a well split close pair of yellow stars about equal magnitude (2.7" 7.79 A & 8.08 B). Unfortunately, this is a triple system with three visible! Missed again! I saw the AB pair but AC is quite widely separated at 137" and a much fainter C at 12.28.
72 Virginis: Bright A and very faint B, widely separated. Luckily this is correct; A 6.14 separated by 29" to 10.74 mag B
STF1775: The losing streak continued: I observed a pretty pairing of a bright orange A and a faint bluish B widely separated. This is probably the AB pair, 27.7" separated and 7.21 mag vs. 10.06. The AC, not noticed, is 38.6" and 14.16 mag.
STF1788: And I closed with a total failure: This is a quintuple system and all 5 are visible. I saw a bright pair of near equal magnitude, both yellow-while color. This is the AB pair. I give you the Stelle Doppie link so you can see how inattentive I was: http://stelledoppie.goaction.it/index2.php?iddoppia=58333
The double session was impromptu, so perhaps I shouldn't be so hard on myself. But, knowing what I can & should see I will retry them the next opportunity.
Mars was now clear of the tree. Seeing had become considerably better, Pickering 8 or 9 -- all the air around me had become still, and the usual loud white noise from the highway was greatly diminished. I pulled out all the stops, as it were: 553x, planetary filter, and apodising screen. It was my best view I've had through my own scope yet, and approaching the very brief look I had through the 36-inch Great Refractor at Lick Observatory about 15 years ago.
Sinus Miridion reached down in a triangular form, with Sinus Sabaeus as a dark barge to the east. The rest of Mare Erythraeum was a dark but somewhat greyish mass covering the rest of the hemisphere; could there have been clouds making the greyish color come out? I noticed two small bright ovals to the west of Margatitifer Sinus but can't account for what it was. Mare Acidalium was a large thick crescent, and I could see the bulge coming out of it to the east, along with some mottling in the brighter plain to the southeast. The southern rim was bright with what could be clouds.
I now understand why observers become so excited during a Mars opposition: with the planet so much closer it offers up a lot more detail. Lin came out for a look and said it looked like the moon -- all the mare visible. I had planned to observe the moon's terminator that night too, but with Mars the way it was I decided to stay on it until bedtime; I can see the moon any month, but not Mars.
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