ASTRO: Opus Returns (observing report, long)

The date on the observing report is not a typo--it really was in July,
at the last LAAS dark sky party but one. But it took me a while to get
around to typing it in, and I felt SAA can use as much honest content as
it can get. So here goes.

7:30 p.m. 14 July 2007 PDT (2007-07-15-0230 UT)

It's been a long time since I did some serious observing with Opus, my
C5+. Having warmed up a couple of weeks ago with a pair of familiar
objects (M4 and M51) back home, I decided to get back into the swing of
things with a trip to Lockwood, the dark sky site of the Los Angeles
Astronomical Society.

I pulled into the site's parking lot while it was still light out, but
only barely. I only had time to set up and wolf down a quick pastrami
sandwich before it was time for the group to get together for general
instructions. Nothing terribly new being said there, but they don't like
anyone to sit these things out. I did contribute a few bucks to the
general fund and went back to my pad.

It was still twilight, and there was still some serious clouds to the
south, which contributed to somewhat lower turnout; a few of the
neighboring observers mentioned that June had brought out maybe 50
observers--twice what had come out this month. So rather than get at the
eyepiece right away, I took out my IS binoculars and took a loook at
Venus and Saturn, close by Regulus.

There is something engaging about seeing Saturn by binoculars that just
barely show the rings, almost as though you were almost gleaning them by
the unaided eye. And the gold-on-gold of Saturn against the fading
twilight is appealing, too. Of course there is no question of seeing the
Cassini Division, or the faint striations of the cloud bands, or
anything like that, but yet, there's something about it that's quite
different from seeing it in a telescope. Maybe it's that in a scope, you
almost feel as though you're in a spaceship lingering just a few million
miles off, whereas with the binoculars, you get a visceral feel for just
how small even such a giant world is in our sky.

After a few minutes, the southern sky was still fairly cloudy, but there
was a break in the clouds for the only object bright enough to make much
of an impression to the unaided eye: Jupiter. Now I am not generally
impressed with the steadiness of the skies at Lockwood. They are of
course dark--reasonably dark for barely 60 miles outside of Los
Angeles--but the seeing there has historically been fairly forgettable.
But one of the nearby observers was watching Jupiter through his 8-inch
SCT, and rather enjoying the view, so I decided to walk over and have a
look.

Jupiter did look reasonably detailed, but not extraordinarily so. I
didn't think the seeing was very good in any absolute sense, though it
was certainly much better than was usual for Lockwood. Still, there was
not yet much else to look at in the sky (other than for the challenge of
seeing them while twilight was still bright), so I too pointed my scope
at the largest planet.

Well, as twilight deepened, the seeing just got better and better, until
after a half an hour or so, it truly was very good in an absolute sense.
Not the best I had ever experienced with Opus--I remember one evening on
the front lawn at Griffith Observatory, before it was renovated, when
the atmosphere seemed to magically part before us--but it was still
certainly very impressive. And since I had not bothered to look at
Jupiter all season with a telescope (binoculars yes, but no scope), I
had no idea what had happened since my last gander.

First and foremost, the equatorial band (EB) had apparently split in
two; at least, the part visible to us had. I'm sure this comes as no
surprise to many of you, but it was totally new to me. Even so, each
half was fairly broad, broader than I had seen the entire band on most
occasions. The northern hemisphere was more or less ordinary looking,
with a pair of festoons perhaps 30 degrees or so of longitude on either
side of the central meridian.

But the southern hemisphere was another story entirely. The south
equatorial belt (SEB) was weak looking, pale and thin. A shadow transit
was at the limb--Ganymede. Someone thought it might have been Ganymede
itself, but no, the black spot was a bit too dark and noticeably
elongated, whereas the satellite itself would have been round. And
PleiadAtlas showed the satellite to have been a Jovian radius off the
limb altogether. The final clincher was all four satellites in view, of
course!

Even beneath the SEB there was plenty of detail. What normally appears
as a vague, nebulous polar region in a small scope was a swirling mass,
waves of faint blue-grey mixed in a sea of ivory. There was a nodule
near the preceding edge of the SEB. I thought at first that it was the
Great Red Spot (GRS), but PleiadAtlas showed that to have rotated around
to the back side of Jupiter already. Does anyone know what that might
have been?

After a while, I figured it was time to take a look at objects that
wouldn't look substantially the same back home. I began with one of the
objects from my trial run at home, M4. This is a fantastic object for
small telescopes, since even a casual glance shows it to be different
from other globulars. Even at home, the north-south bar is fairly
straightforward to see, and from Lockwood, it was distinct, and began to
show some variation in thickness and even texture along its length. One
can verify, with an polar-aligned mount, that the bar is not quite north
and south, by twiddling the declination knob.

Next up was M22, except that I misidentified it from memory. If anything
shows you how rusty I was, that was it. A nice lady and her grandson
were out for a test run with his small refractor (a Celestron 60 mm, I
think--computerized, but they weren't using the computer) and were
asking about nice objects to look at. I pointed it at M22, going
northeast from the tip of the teapot of Sagittarius, past a trio of
sixth-magnitude stars, to a nice fuzzy patch, but I called it M25. No
sooner had I said it when I had a misgiving about its identity, but I
didn't say anything further. A quick check with PleiadAtlas a few
moments later revealed my error. (M25 is, in fact, an open cluster in
the same general region of the sky, but not particularly near M22.)

Incidentally, the last time I was at Lockwood, I was still using a Palm
m505, the next generation of my original Palm Vx. Both of those were
monochrome devices, which I darkened to acceptable levels with neutral
density sheeting (3 or 4 stops, I think). But the Treo 680 I use now has
a color display. PleiadAtlas has an option to turn the color display
red, so I used that, but unfortunately, the keyboard is also lit up, and
I had no sheeting for that. So before I head back up to Lockwood the
next time, I have to figure out a solution for that. For the rest of the
night, I resorted to the old-fashioned method of atlases and books, plus
the red flashlight.

For a while after the M25 impostor, I skimmed through the Barnard
nebulae in Sagittarius. I wasn't aiming at anything in particular, since
this is something I do more typically with the 10-inch dob sporting the
55 mm Plossl; I just wanted to gain a feel for the place. I did try
hunting down one thing, which I know by appearance but not by name. One
of the LAAS oldtimers who doesn't observe much more with the group had
directed me toward what he nicknamed the Inverse Ring Nebula. It is a
dark nebula in the shape of a donut, and it does rather resemble a
photo-negative version of the more famous Ring Nebula (M57). He showed
me where it was, and then I vaguely surprised him by being able to find
it again in a few seconds--which makes my inability to find it in the
years since all the more frustrating. No one else at the site,
experienced or otherwise, could figure out what I was searching for,
either. (Nonetheless, I'm not making this up!) If this description
sounds familiar at all to anyone, please let me know what it is I'm
looking for.

After some time, I gave up and began looking for easier stuff. M8 and
M20 are far less frustrating than hard-to-find dark nebulae through a
small scope; in fact, while I was hunting for the Dark Donut, I ran
across M20 by accident on no fewer than three occasions. Even from my
bright backyard, M8 is a good sight, but M20 suffers, of course. From
Lockwood, it is a delicate-looking thing, nothing like through the
10-inch, but still showing the three petals that give it its nickname,
the Trifid.

With that, it was time to try for some more serious stuff. First up was
vdB 126, a mixture of dark and reflection nebulae surrounding an
eighth-magnitude star in Vulpecula. Perhaps a few arcminutes across, it
is described as a challenge in a 6-inch from suburban skies, but even
from dark skies, I could make out no significant sign of it through the
5-inch.

Matters were improved, sort of, on my next target, Sharpless 2-82, a
combination of emission and reflection nebulae. I did get a feeling that
there was a glow to the side of the brightest star (not the star that
lights up the reflection nebula), but to be honest, I could also get
that feeling about half a dozen other stars in the field of view. It's
important to confirm observations that you particularly want to make!
The UltraBlock (Orion's narrowband filter) did seem to make the target
glow somewhat more prominent, relative to the others, but I could not
chalk it up as definitely seen. Probably seen, though.

IC 4996 is a small, sparsely-populated open cluster in Cygnus. It's
mostly made up of several ninth to eleventh-magnitude stars, with maybe
a layer or so of dimmer stars "underneath." Through the C5+, it's pretty
underwhelming, if at least distinctly visible. The undercurrent of
dimmer stars is not strongly detectable in such a small scope, since
such dimmer stars are visible everywhere throughout Cygnus, and they are
only somewhat denser within IC 4996 (if at all).

My last serious telescopic object was NGC 6871, another open cluster in
Cygnus. Fairly easily seen, and even though it's also fairly sparse, it
does at least have an appealing three-dimensional look to it, almost as
though the stars were highlighting the corners of some celestial
polyhedron. The brightest star of NGC 6871 is fifth-magnitude 27 Cygni
off to the north, not a true member, as it's an orangish K0 only about
80 light-years distant, whereas NGC 6871 is a few dozen times further.

I said my last serious target was NGC 6871, but not my last target. I
did aim Opus at NGC 7000, the North America Nebula, though not with any
particular expectation of seeing it (and I didn't). Nor did I find
anyone with a proper filter to use, although I did not try using the
UltraBlock, as I should have. Next time, perhaps.

It was about one in the morning by this time, so I packed up the scope
and put it back in the car. I must remember to either not turn on the
car lock next time (the beep bathed the field in a red glow) or figure
out a way to keep it from lighting up when I unlock it. I took the
binoculars out one last time to look at M31 rising in the east; M32 and
M110 were easily seen with it, of course. Something to remember for the
next time I come out to Lockwood--in September, I hope.

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

Thank you, Brian for a most astute and comprehensive report.

My observations have been limited to the bino because the
temperatures around here remain above 80dF most of the night
and I have trouble concentrating whien its that warm.

Then there's the mosquitoes....

Looks like you had a great outing.

Ben

There is something engaging about seeing Saturn by binoculars that just
barely show the rings, almost as though you were almost gleaning them by
the unaided eye. And the gold-on-gold of Saturn against the fading
twilight is appealing, too. Of course there is no question of seeing the
Cassini Division, or the faint striations of the cloud bands, or
anything like that, but yet, there's something about it that's quite
different from seeing it in a telescope. Maybe it's that in a scope, you
almost feel as though you're in a spaceship lingering just a few million
miles off, whereas with the binoculars, you get a visceral feel for just
how small even such a giant world is in our sky.


Thank you, Brian, for that wonderful report, especially the paragraph on
Saturn! Your description brought back memories of my first view of the
planet Saturn: it was an extremely cold night, so I was looking low out to
the west with a patio doors closed. My planetarium software said Saturn
should be there, and pointing 10 x 50 binoculars in the correct spot reveals
an elongated goldish dot. I believe later I look through either my Tele Vue
Pronto or C5+ reflector and saw Saturn as a ringed world for the first time.
I was always tempted to try for more magnification on Saturn in both the
scopes, but it always looks sharper and seemed more three dimensional using
less not more magnification.

If it ever stops raining in Chicago, I may have to drag out my C5 plus and
try for Saturn or Jupiter again. Thanks for the inspiration!

Steve

SZumbo wrote:
Thank you, Brian, for that wonderful report, especially the paragraph on
Saturn! Your description brought back memories of my first view of the
planet Saturn: it was an extremely cold night, so I was looking low out to
the west with a patio doors closed. My planetarium software said Saturn
should be there, and pointing 10 x 50 binoculars in the correct spot reveals
an elongated goldish dot. I believe later I look through either my Tele Vue
Pronto or C5+ reflector and saw Saturn as a ringed world for the first time.
I was always tempted to try for more magnification on Saturn in both the
scopes, but it always looks sharper and seemed more three dimensional using
less not more magnification.

It does, somewhat, but generally, the point of most detail is not the
same as the point of sharpest appearance. My eyes are pretty acute, so
the latter happens at about 15x to 20x per inch, but I find I see the
most detail--seeing permitting--at closer to 30x to 40x per inch.

If it ever stops raining in Chicago, I may have to drag out my C5 plus and
try for Saturn or Jupiter again. Thanks for the inspiration!

You're quite welcome. I'm still pondering taking the scope out myself
this evening, as late as it is...

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html

great post and ASTRO: header is a wise idea - all should do it -
it was suggested earlier. Thanks Brian. When push comes to shove we are all
together here. ....





Brian Tung wrote:

The date on the observing report is not a typo--it really was in July,
at the last LAAS dark sky party but one. But it took me a while to get
around to typing it in, and I felt SAA can use as much honest content as
it can get. So here goes.

7:30 p.m. 14 July 2007 PDT (2007-07-15-0230 UT)

It's been a long time since I did some serious observing with Opus, my
C5+. Having warmed up a couple of weeks ago with a pair of familiar
objects (M4 and M51) back home, I decided to get back into the swing of
things with a trip to Lockwood, the dark sky site of the Los Angeles
Astronomical Society.

I pulled into the site's parking lot while it was still light out, but
only barely. I only had time to set up and wolf down a quick pastrami
sandwich before it was time for the group to get together for general
instructions. Nothing terribly new being said there, but they don't like
anyone to sit these things out. I did contribute a few bucks to the
general fund and went back to my pad.

It was still twilight, and there was still some serious clouds to the
south, which contributed to somewhat lower turnout; a few of the
neighboring observers mentioned that June had brought out maybe 50
observers--twice what had come out this month. So rather than get at the
eyepiece right away, I took out my IS binoculars and took a loook at
Venus and Saturn, close by Regulus.

There is something engaging about seeing Saturn by binoculars that just
barely show the rings, almost as though you were almost gleaning them by
the unaided eye. And the gold-on-gold of Saturn against the fading
twilight is appealing, too. Of course there is no question of seeing the
Cassini Division, or the faint striations of the cloud bands, or
anything like that, but yet, there's something about it that's quite
different from seeing it in a telescope. Maybe it's that in a scope, you
almost feel as though you're in a spaceship lingering just a few million
miles off, whereas with the binoculars, you get a visceral feel for just
how small even such a giant world is in our sky.

After a few minutes, the southern sky was still fairly cloudy, but there
was a break in the clouds for the only object bright enough to make much
of an impression to the unaided eye: Jupiter. Now I am not generally
impressed with the steadiness of the skies at Lockwood. They are of
course dark--reasonably dark for barely 60 miles outside of Los
Angeles--but the seeing there has historically been fairly forgettable.
But one of the nearby observers was watching Jupiter through his 8-inch
SCT, and rather enjoying the view, so I decided to walk over and have a
look.

Jupiter did look reasonably detailed, but not extraordinarily so. I
didn't think the seeing was very good in any absolute sense, though it
was certainly much better than was usual for Lockwood. Still, there was
not yet much else to look at in the sky (other than for the challenge of
seeing them while twilight was still bright), so I too pointed my scope
at the largest planet.

Well, as twilight deepened, the seeing just got better and better, until
after a half an hour or so, it truly was very good in an absolute sense.
Not the best I had ever experienced with Opus--I remember one evening on
the front lawn at Griffith Observatory, before it was renovated, when
the atmosphere seemed to magically part before us--but it was still
certainly very impressive. And since I had not bothered to look at
Jupiter all season with a telescope (binoculars yes, but no scope), I
had no idea what had happened since my last gander.

First and foremost, the equatorial band (EB) had apparently split in
two; at least, the part visible to us had. I'm sure this comes as no
surprise to many of you, but it was totally new to me. Even so, each
half was fairly broad, broader than I had seen the entire band on most
occasions. The northern hemisphere was more or less ordinary looking,
with a pair of festoons perhaps 30 degrees or so of longitude on either
side of the central meridian.

But the southern hemisphere was another story entirely. The south
equatorial belt (SEB) was weak looking, pale and thin. A shadow transit
was at the limb--Ganymede. Someone thought it might have been Ganymede
itself, but no, the black spot was a bit too dark and noticeably
elongated, whereas the satellite itself would have been round. And
PleiadAtlas showed the satellite to have been a Jovian radius off the
limb altogether. The final clincher was all four satellites in view, of
course!

Even beneath the SEB there was plenty of detail. What normally appears
as a vague, nebulous polar region in a small scope was a swirling mass,
waves of faint blue-grey mixed in a sea of ivory. There was a nodule
near the preceding edge of the SEB. I thought at first that it was the
Great Red Spot (GRS), but PleiadAtlas showed that to have rotated around
to the back side of Jupiter already. Does anyone know what that might
have been?

After a while, I figured it was time to take a look at objects that
wouldn't look substantially the same back home. I began with one of the
objects from my trial run at home, M4. This is a fantastic object for
small telescopes, since even a casual glance shows it to be different
from other globulars. Even at home, the north-south bar is fairly
straightforward to see, and from Lockwood, it was distinct, and began to
show some variation in thickness and even texture along its length. One
can verify, with an polar-aligned mount, that the bar is not quite north
and south, by twiddling the declination knob.

Next up was M22, except that I misidentified it from memory. If anything
shows you how rusty I was, that was it. A nice lady and her grandson
were out for a test run with his small refractor (a Celestron 60 mm, I
think--computerized, but they weren't using the computer) and were
asking about nice objects to look at. I pointed it at M22, going
northeast from the tip of the teapot of Sagittarius, past a trio of
sixth-magnitude stars, to a nice fuzzy patch, but I called it M25. No
sooner had I said it when I had a misgiving about its identity, but I
didn't say anything further. A quick check with PleiadAtlas a few
moments later revealed my error. (M25 is, in fact, an open cluster in
the same general region of the sky, but not particularly near M22.)

Incidentally, the last time I was at Lockwood, I was still using a Palm
m505, the next generation of my original Palm Vx. Both of those were
monochrome devices, which I darkened to acceptable levels with neutral
density sheeting (3 or 4 stops, I think). But the Treo 680 I use now has
a color display. PleiadAtlas has an option to turn the color display
red, so I used that, but unfortunately, the keyboard is also lit up, and
I had no sheeting for that. So before I head back up to Lockwood the
next time, I have to figure out a solution for that. For the rest of the
night, I resorted to the old-fashioned method of atlases and books, plus
the red flashlight.

For a while after the M25 impostor, I skimmed through the Barnard
nebulae in Sagittarius. I wasn't aiming at anything in particular, since
this is something I do more typically with the 10-inch dob sporting the
55 mm Plossl; I just wanted to gain a feel for the place. I did try
hunting down one thing, which I know by appearance but not by name. One
of the LAAS oldtimers who doesn't observe much more with the group had
directed me toward what he nicknamed the Inverse Ring Nebula. It is a
dark nebula in the shape of a donut, and it does rather resemble a
photo-negative version of the more famous Ring Nebula (M57). He showed
me where it was, and then I vaguely surprised him by being able to find
it again in a few seconds--which makes my inability to find it in the
years since all the more frustrating. No one else at the site,
experienced or otherwise, could figure out what I was searching for,
either. (Nonetheless, I'm not making this up!) If this description
sounds familiar at all to anyone, please let me know what it is I'm
looking for.

After some time, I gave up and began looking for easier stuff. M8 and
M20 are far less frustrating than hard-to-find dark nebulae through a
small scope; in fact, while I was hunting for the Dark Donut, I ran
across M20 by accident on no fewer than three occasions. Even from my
bright backyard, M8 is a good sight, but M20 suffers, of course. From
Lockwood, it is a delicate-looking thing, nothing like through the
10-inch, but still showing the three petals that give it its nickname,
the Trifid.

With that, it was time to try for some more serious stuff. First up was
vdB 126, a mixture of dark and reflection nebulae surrounding an
eighth-magnitude star in Vulpecula. Perhaps a few arcminutes across, it
is described as a challenge in a 6-inch from suburban skies, but even
from dark skies, I could make out no significant sign of it through the
5-inch.

Matters were improved, sort of, on my next target, Sharpless 2-82, a
combination of emission and reflection nebulae. I did get a feeling that
there was a glow to the side of the brightest star (not the star that
lights up the reflection nebula), but to be honest, I could also get
that feeling about half a dozen other stars in the field of view. It's
important to confirm observations that you particularly want to make!
The UltraBlock (Orion's narrowband filter) did seem to make the target
glow somewhat more prominent, relative to the others, but I could not
chalk it up as definitely seen. Probably seen, though.

IC 4996 is a small, sparsely-populated open cluster in Cygnus. It's
mostly made up of several ninth to eleventh-magnitude stars, with maybe
a layer or so of dimmer stars "underneath." Through the C5+, it's pretty
underwhelming, if at least distinctly visible. The undercurrent of
dimmer stars is not strongly detectable in such a small scope, since
such dimmer stars are visible everywhere throughout Cygnus, and they are
only somewhat denser within IC 4996 (if at all).

My last serious telescopic object was NGC 6871, another open cluster in
Cygnus. Fairly easily seen, and even though it's also fairly sparse, it
does at least have an appealing three-dimensional look to it, almost as
though the stars were highlighting the corners of some celestial
polyhedron. The brightest star of NGC 6871 is fifth-magnitude 27 Cygni
off to the north, not a true member, as it's an orangish K0 only about
80 light-years distant, whereas NGC 6871 is a few dozen times further.

I said my last serious target was NGC 6871, but not my last target. I
did aim Opus at NGC 7000, the North America Nebula, though not with any
particular expectation of seeing it (and I didn't). Nor did I find
anyone with a proper filter to use, although I did not try using the
UltraBlock, as I should have. Next time, perhaps.

It was about one in the morning by this time, so I packed up the scope
and put it back in the car. I must remember to either not turn on the
car lock next time (the beep bathed the field in a red glow) or figure
out a way to keep it from lighting up when I unlock it. I took the
binoculars out one last time to look at M31 rising in the east; M32 and
M110 were easily seen with it, of course. Something to remember for the
next time I come out to Lockwood--in September, I hope.

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html