by David Kingsley
As expected, it was cold. Temps were below freezing most of the observing session, hovering around 28 most of night, with a brief warming up to about 39 around 10 or 11 pm. Fortunately, there was no real wind to speak of. Humidity was low enough that there was also no extensive problems with dewing, just occasional fogging of eyepieces near warm eyes and faces. I bundled up with a hat, gloves, 2 coats, snow pants,2 pairs of socks, and wool-lined boots. That kept me warm throughout the night, and made it possible to thoroughly enjoy some of the first clear skies I have seen with my 14.5 inch scope since the sub-arcsecond viewing session up at Montebello right before Thanksgiving.
The moon was already several days past new. The lunar crescent hanging in the sky encouraged me to spend the early part of the night looking at planets and bright objects. The Moon itself was beautiful. The Rupes Cauchy region of the Sea of Tranquility was well illuminated, with a huge black fault as prominent as the much more famous Straight Wall that is located much further west. Two pretty domes were visible south of Cauchy (Omega and Tau Cauchy), along with a wide long rille to the that runs roughly parallel to Rupes Cauchy further north. A great grouping of different kinds of lunar objects (see chart 36 in Rukl).
After using my left eye for the moon, I used my right eye for a quick star hop to comet T7 linear near M33. The comet was visble in the 9x50 finder scope as a small bright patch. In the telescope it clearly showed a brighter nucleus and an asymmetric tail. I asked Ray if he would like to take a look. He already knew the name and rough position of the comet, even though he has only been observing a couple of months. Ray is going through lots of objects for the first time with the help of Turn Left at Orion. This was one of the books I had also started with, and has an excellent selection of both objects, descriptions, and background information. Shortly afterwards, Ray was hunting M1, one of the Messier objects that really actually looks sort of like a comet. It was fun to go back and forth between a current comet in the sky, and the first object that Messier had seen while comet hunting that inspired him to begin a list of other nebulous objects in the sky.
After the comet and M1 I stopped in briefly at M103, on open cluster in Cas that I had recently heard described as resembling a Christmas Tree cluster. Sure enough the stars are are laid out in a nice triangular shape, with a brighter one at the top and some ornaments hanging on the side. I hadn't looked at this in years, but will make a habit of stopping back again around the holidays.
Mars was hanging bright in the sky, now nearly four months past opposition. I swung over to take a look, and could still see some detail on the shrinking disc. I made a sketch but suspect this will be the last of the large series I started way back in May, when I first saw Mars rising in the East near the end of an observing session up at Henry Coe. At nearly the same time I was sketching Mars at Fremont Peak, the big radio telescope at Stanford was scanning the surface of Mars trying to detect any signal from Beagle 2. After reading so much about Mars over the summer, I have really been looking forward to the new exploratory missions from both Europe and the US. It looks grim now for Beagle2, but I am keeping my fingers crossed for the two US probes arriving in January.
With the moon still casting obvious shadows throughout the parking lot, I decided to take a look at other bright targets. Saturn was absolutely beautiful last night at magnifications up to 450x The crepe ring was very obvious all around the planet, with lots of other structure and brightening in the A and B rings. Beautiful banding was also visible on globe. While soaking in the views, I was surprised to see two dark ears poking out behind the planet where Saturn's edge was superimposed over the ring behind it. Each small black ear almost identical in size. While looking at this, I thought it must be the shadow of the planet projected on the rings. However, a shadow could only produce symmetric black ears if Saturn was very near opposition. I subsequently checked Karkoschka's handy atlas, and sure enough Saturn last night was only a few days away from its opposition on December 31st, 2003. I have previously watched the shadows of Jupiter's moons switch from the preceeding to following side of the tiny moons as Earth caught up with and passed the king of planets near opposition (http://www.observers.org/reports/2000.11.27.html). Saturn's rings make it possible to see a similar effect with the shadow of an entire planet. The two symmetric black ears were an interesting bonus to a wonderful view. I suspect that by the time that I get a chance to look again, the shadow on the following side will start to grow as the earth pulls away from Saturn after opposition.
(for anyone who wants to see an image of the symmetric black ears
effect, there happened to be a post today by someone on the AP-user
Yahoo group who imaged Saturn imaged last night with an 8 inch F/15
AP. The views through both the 14.5 inch and 20 inch starmaster last
night at Fremont Peak, were actually somewhat sharper than what was
recorded in the image, but it gives you some idea of the detail
visible in moments of good seeing last night , and the two black
ears. Unfortunately, you may have to joint the yahoo group to see
the file
http://groups.yahoo.com/group/ap-ug/files/17Saturn12-27-03.jpg )
Some much higher resolution images can also be seen on Damian Peach's
public web site, covering the changing appearance of Saturn and its
ring shadows during the 2002 and 2003 opposition:
http://homepage.ntlworld.com/damian.peach/sat_02.htm
Ray was also hunting the Eskimo nebula (NGC 2392) in Gemini last night, located not too far away from Saturn. We played with different eyepieces and barlows in the Nexstar to vary the magnification, and then compared views as we stepped up in aperture. In the 8 inch Nexstar, the central star and planetary nebula was obvious, and an OIII filter and high magnification brought out hints of an inner shell with averted vision. In the 14.5 inch starmaster, some inner ring structure was clearly visible without an OIII filter, but usually looked discontinuous, with brightest part constantly visible, and the rest coming and going with seeing. Adding the OIII made it obvious there was a continuous inner shell, that could now be easily held constantly with direct vision. When we looked through Peter's 20 inch later in night, it was possible to hold the continuous ring easily without the OIII filter. Adding the OIII still helped (more than a lumicon UHC), mostly making the inner shell brighter and fatter. The improvement was not as big as in the 14.5 inch however, because the 20 inch already collected enough light to show most of the inner shell even in the unfiltered view. We later hunted this again in Peter's 80 mm Nighthawk. The difference between the nebula and nearby field stars was clear, but the nebula obviously did not show the the structure visible in the larger scopes. It was fun to play with a range of apertures, eyepieces, and filters on a single object. Thanks to everyone for the comparisons.
The moon was now low enough, and Orion was high enough, that I spent
the rest of the night going through an old Alan MacRobert tour of the
belt and sword of winter's best constellation (SkyTel January 1998).
I usually check out the great Orion nebula at least once every night
I set up in the winter. M42 is so spectacular that it is easy to
overlook all the other cool stuff nearby. I had a very enjoyable
time going through a nice set of double and multiple stars, emission
and reflection nebula, dark nebula, and clusters from the brilliant
belt star zeta Ori to the very interesting NGC 1999 nebula a the
bottom of the sword. MacRobert includes lots of interesting
information on unusual features of the stars themselves, including
spectra, distances, orbits, and enough diagrams that it was possible
to hop along easily through a huge range of objects (multiple stars
including zeta Ori, three nearby doubles, sigma Ori, struve 761, the
trapezium, iota Ori, Struve 747; unusual variables like KX, V901, and
V359 Ori; clusters like 1981; and lots of reflection, emission, and
dark nebula including IC431, IC432, NGC 2024 ( flame nebula),
NGC2023, IC435, IC434, the horsehead, NGC 1973, 1975, and 1977, M43,
M42, and NGC1999. Too bad so much of this stuff is overshadowed by
its brilliant neighbor. M43 would be a much more popular object in
its own right if it wasn't right next door to M42. NGC1999 was the
last thing on the tour, but an interesting mix of nebulosity
surrounding a star, and an obvious dark patch on one side. See
http://www.ne.jp/asahi/stellar/scenes/object_e/ngc1999.htm
for both an amateur and hubble telescope view of this very interesting region.
I had looked at many of these Orion objects before, mostly with a 7 inch Starmaster in a rush of excitement and discovery doing the Messier and Herschel 400 lists when I first got started with astronomy. It was great fun to go back and look again with the larger 14.5 inch scope. I also find I am learning more about the objects themselves on subsequent visits, rather than just enjoying the views. MacRobert is an excellent writer for bringing together both the science and beauty of the objects. I have also been picking up interesting astrophysical details about many eyepiece objects in the recently published book, Concise Catalog of Deep Sky Objects by W.H. Finlay. Finlay summarizes, ages, distances, sizes, galaxy position, and relevant scientific details from the research literature for 520 deep sky objects, including the entire Messier Catalog, the Herschel 400, and the RASC's finest 110 NGC objects. In his sections on many of the things I looked at last night, Finlay points out that the huge concentration of emission nebula, gas, dust, and new star clusters in the Orion/Monoceris region are part of an enormous molecular gas cloud that is positioned about 500 light years south of the disk of the Milky Way. The size, position, and properties of the cloud suggest it was likely produced by recent infall of a gargantuan gas clouds into the plane of our galaxy from below. Interestingly, the current issue of Scientific American has a long article on how our galaxy was likely built (and is still evolving) by the continual accumulation of infalling clouds of gas, dust, and nearby galaxies. The visual delights in Orion provide a great way to actually see the results of this process in the eyepiece. I learn something new almost every time I come back to this region with a telescope, each visit helping reveal new parts of a much larger picture of the universe.
By midnight, bands of clouds were starting to fill the western sky up to 45 degrees or so of altitude. Pete had torn down, and soon found that his car battery had been completely drained while providing power for his dew heaters and mount during the night. Ray came to the rescue with the cables from a telescope mount, and Pete got started before having to attempt any major surgery of swapping batteries in and out of his car. The rest of us also packed up soon after, after nearly 6 hours of observing.
Roads were frosty and slick in parts on the way down the mountain. One patch sparkled brightly with tiny ice crystals against the dark road, reminding me of of some of the beautiful sights I had seen in the eyepiece earlier in the night. I have never driven more slowly or carefully down from Fremont Peak, but was very happy I decided to make the observing trip, despite the cold.
Happy new year, and best wishes to both new and old observers in 2004.
