Wednesday, April 13, 2005

Emptying the Cup!

Last night my daughter Mimi, boyfriend Jeff and I joined Peter Natscher for a short night of observing on Coulter Row at Fremont Peak. It has been forever since I've observed from that location. I can report that the site is still quite good, and has seen some nice improvements since my last visit - new restrooms up at the overlook, and good pavement. I brought my 18" f/4.5 Obsession and 10" f/5.7 CPT, Mimi got to use the smaller scope to show her boyfriend some highlight objects. It was a short night for Mimi, as the cold got to her, and she was gone by eleven.

I decided to go to the Peak - my annual trip - and try Coulter as it is protected somewhat from the wind, has a very good southern horizon, and Peter was going. I had not seen him since Shingletown last year. I enjoyed the evening - Peter and I were swapping views - he had several nice galaxy groups during the night.

I was continuing my Herschel 2500 project. Man, what a task. My hat's off to folks like Gottlieb and Czerwinski, who've logged that many objects and (in Steve's case) more. I've been at this off and on for a very long time. Last night I went after objects in Crater, which was among the springtime constellations that are so difficult to get clear skies for. As noted in Peter's report, temps were chilly, dropping into the mid 30's, but other than my fingers, I was not cold.

Here are the objects I observed:

NGC 3081Galaxy type SAB, mag 12.85, SB 13.2, size 2.1'x1.6': I began hunting this target (actually in Hydra) in the late twilight, and found the location difficult. Using Alphard (Alpha Hydrae) and making a right angle with Lambda Hydrae, I ended up using the naked eye pair of stars SAO 177840 and SAO 177866, which are 23' apart, to hop via my 10x70 finder to the correct position. The galaxy was dim, but had a bright non-stellar core surrounded by a dim halo disk. It is located off a nice chain of six stars to its NE. There may be some elongation NNW/SSE.
NGC 3892Galaxy type SO, mag 11.5, SB 13.4, size 3.0'x2.2': I hopped from Alpha Crateris to Delta, and out NE to mag 6.2 SAO 156896, which made the position easy to locate. The galaxy is small, oval with some elongation E/W. It contains a bright core with a dim stellar point.
NGC 3956Galaxy type Sc, mag 12.1, SB 13.3, size 3.4'x1.0'. This one appeared as a dim slash ENE/WNW with even brightness throughout. There were two pair of stars of equal PA to the NNW that helped locate the galaxy. I found this one going form Delta to Gamma Corvi and down to mag 5.2 SAO 157042, and the galaxy was just beyond, barely inside Crater's border.
NGC 3962Galaxy type E2, mag 10.7, SB 12.6, size 2.6'x2.2'. This was one of the tougher locations, without a bright star nearby. I went from Gamma Corvi to mag 5 SAO 156998, then north, and hunted around a bit. There were two bright stars nearby to the S and SW that helped mark the location, but the galaxy itself was quite bright and obvious in the eyepiece. It had a stellar core with a bright inner disk that diffused abruptly out to a dim outer disk.
NGC 3981Galaxy type Sbc, mag 11.3, SB 13.8, size 5.2'x2.3'. Very near the location of NGC 3956, this very long galaxy had an even brightness and was in a WSW/ENE position.
NGC 3456Galaxy type SBc, mag 12.4, SB 12.9, size 1.9'x1.3'. Located at the western extreme of Crater, it is easy to locate star hopping from mag 3.1 Nu Hydrae. It is small, very dim and elongated E/W with a dim star just to its E. There was no detail. But, I do like sequential NGC numbers like this one (my favorite is NGC 6543).
NGC 3571Galaxy type Sa, mag 12.1, SB 13.2, size 3.0'x1.0'. In an easy position in Crater nearly mid-point between Alpha and Gamma. This appeared to be edge-on, had a bright core with a near stellar nucleus, and seemed quite elongated E/W 5x2.
NGC 3715Galaxy type SO, mag 13.9, SB 12.7, size 0.8'x0.5'. At first I thought I was just dyslexic and had transposed numbers with the prior object, but no, this was really the next on my list. It is located very close to NGC 3571, on the same line toward Alpha Crateris. Small, bright and round, with a stellar core.
NGC 3667Galaxy type Sbc, mag 12.7, SB 12.4, size 1.5'x1.0'. Very easy to locate going from Alpha to Delta, then another 1.5 degrees further. This galaxy appears oval and even brightness, elongated E/W. Bumping up the power brought out NGC 3667A, much dimmer, but about the same size as 3667 which is to its W. 3667A forms a right angle with 3667 and a close star. 3667A is elongated NE/SE and is separated by only 1'.
NGC 3955Galaxy type SO, mag 11.9, SB 12.9, size 2.9'x0.9'. I used mag 3 Epsilon Corvi and mag 4 Alpha Corvi (yes, you read those mags correctly) to form an isosceles triangle to locate this target. This was a nice view, very elongated N/S with a pronounced bright large central bulge. A very slight hint of a stellar core - the southern extent of the galaxy seemed to be disrupted, or perhaps it is a barred spiral - there seemed to be hints of arms curving back of the ends of the extensions.
NGC 3957Galaxy type SO, mag 11.8, SB 12.5, size 3.1'x0.7'. Nice! Bright, very elongated about 5X1 N/S, with a dark area in the S extension. In an easy position to locate, Delta to Gamma Corvi, to SAO 157042, and a bit west - three stars to the galaxy's NW help mark the field.
NGC 3732Galaxy type EO, mag 12.5, SB 12.8, size 1.2'x1.2'. Too easy to find, just off mag 4.7 Theta Crateris. It is small, round and has a stellar core in a bright nucleus. A bright star sits close to its W.
NGC 3508Galaxy type Sb, mag 13.2, SB 12.9, size 1.0'x0.9'. Located very close to a pair of naked-eye stars just N of Alpha Crateris. It appears irregular, elongated SSW/NNE, possibly larger on the SSW end. It has a star embedded in the NNE end. I wonder if this galaxy is disrupted?
NGC 3951Galaxy type SBO, mag 13.1, SB 13, size 1.3'x0.8'. Easy hop off of Delta Crateris, however, this proved a difficult object. It was odd that it was *just* visible in my 20 Nagler (100X), but not in the 12 or 7 Naglers. As such, the best description I can attach is, non-descript!
NGC 3661Galaxy type SO, mag 14, SB 14.2, size 1.7'x0.8'. Great location! Go from Alpha to Delta and just beyond - really easy. The galaxy is elongated SSE/NNW with a bright core containing a dim stellar point. I felt there was some mottling. An easy bright chain of three stars sits very close to the galaxy's south.
NGC 3734Galaxy type Sbc, mag 13.7, SB 13.9, size 1.4'x1.0'. I used Iota (24) Crateris as the jumping off point to hop to this target. It was extremely faint and yielded no detail. I could see it only in the 12 Nagler and even then, only by jiggling the telescope, which showed a round ghost coming in and out with averted vision.
NGC 3791Galaxy type SO, mag 13.7, SB 13.8, size 1.3'x1.0'. This was a fun target, and my last for the night. Alpha and Delta to hop to mag 4.7 Theta Crateris, then star hopped to the galaxy from there. The galaxy was small and round, averted vision showed a stellar core. It was easy to pick out a low power. Three other galaxies in a tight knot - NGC 3771, MCG 1-30-17 and MCG 1-30-18 break up nicely at high power (280X), although the two MCGs are very close together. One oddity was that NGC 3791seemed to have a double nucleus at high power.

That was it for the night. I had finished off the objects in Crater, emptied the cup of H2500 objects.

Before finishing, I will say, as I do each year, off of Highway 101 along 156 then up San Juan Canyon Road is one of the most beautiful I know of in spring. It is verdant green, there are wildflowers on the shoulders of the road, and cattle, horses, rabbit and wild turkey around the turns. The view of the coast from Fremont Peak is a treat.

I also found that it was not too bad observing galaxies with a 5+ day old moon. Earlier in the day I wrote Attilla Danko, ex-bay area resident (used to attend our Lassen Star Parties) asking him about an additional feature for the clear sky clocks. I wondered if there could be a way to quantify magnitude loss for various percentages of the moon - for its phase, and for certain degrees off the moon - and perhaps model in transparency as well. This would help tell observers if the targets they are interested in would be visible, or "mooned" out on a particular night. I did not mind having the moon up... I'll do it again. I might even go back to the Peak again before next year!

Saturday, April 9, 2005

Coe beats the odds

I started the day Saturday looking at the Clear Sky Clocks for Coe, Plettstone and other points south in the Sierra Foothills. Turned out that by mid-afternoon, Coe looked the best...

And, it exceeded our expectations. Conditions were cool, but not cold, dewy early on then drying out, calm winds that picked up around midnight, and reasonably steady seeing even for planetery observing. As usual, the drive up East Dunne Road through the green mountaintops and canyons was beautiful.

Three of us met there, all with 18" telescopes, two f/4.5s, the other must be an f/5. We had few visitors, just some day hikers at sunset, and then a group with headlamps on walking into the parking lot while we were observing - they quickly agreed to douse their lights and look through the telescopes. Its always fun to hear someone react to seeing Saturn the first time...

This was my second night at Coe in less than a week. I have been observing object in William Herschel's catalog, and continued in Coma Berenices, which is now quite a familiar constellation for me. While the transparency was better on Tuesday night, I had little trouble locating most targets last night. Here are my notes:

NGC 4919A - this galaxy is very faint, just a glint between NGCs 4919 and 4911. NGC 4911 is obvious, 4919 is more difficult but still direct vision. The only time 4919A was visible was with averted vision.

NGC 4927 sits inside the lip of a nice little Big Dipper asterism, and is "there" but difficult in my 20 Nagler. Bumping up the power with the 12 Nagler makes the galaxy much easier to observe - still - it is indistinct - a stellar core pops out with averted vision.

NGC 4983 - there is a nice "arrow" of four stars - very distinct - that point to this galaxy. Reminds me of the pointer that helps find M104. The galaxy is dim, medium size, but shows no detail. Much more obvious is nearby galaxy UGC 8229, which is elongated N/S.

NGC 4921 at first rated a "maybe"... in fact, I thought for quite a while (spent way to much time on this one) I thought it could be misplotted. It does not show up on The Sky, something I would run into off and on during the night, but the pointer would show the location it should occupy. Others were all around, this is a fun galaxy field. Showing up were NGCs 4022, 4023, 4015, 4016, 3987, 3997 and 4018. After carefully star hopping in the eyepiece (7 Nagler) 4021 finally showed itself, very near by a dim star and further away from the two pointer stars I thought it was equidistant from.

NGC 4074 was a dim but not difficult galaxy, with a dim star very near by to its west. This was another fun galaxy field, yielding NGCs 4070, 4066, 4065, 4061, 4076, 4086, 4090, 4093 and 4095.

NGC 4559 is a galaxy with designations of A, B and C. The galaxy was fun to view, after all the dim stuff, as it was large and bright. It is large, roundish and has three stars embedded in the southern half. There are two bright knots, which I take to be the B and C designations, in the northern section, the brighter one being more central, and the dimmer on on the northern extremity, and very dim. There is also a possible knot to the northeast.

NGC 4979 is an obvious N/S elongated galaxy that forms a right angle with the two brightest stars in the field.

NGC 5004B and C and IC 4210 were puzzling, at least the NGCs were - The Sky does not use letter designations consistently, sometimes it uses them, other times not. The NGCs were easy, there is a nice star pattern to work off of. The IC is very difficult, a dim star just to its E helps mark the location.

NGC 4035 is a possible elongated galaxy. Or perhaps its spiral arms give it an elongated appearance. I could only detect this detail at 280X. Getting there was a big problem... I was sure I was in the right field, all stars except the mag 9 one located dead on the galaxy were there... and I wasn't seeing the galaxy at low power. I finally realized The Sky had the star misplotted, badly, after looking at the thumbnail image. I went to the position, bumped up the power, and there was 4035.

My last object was NGC 4714 - nice, obvious. An easy, bright asterism makes the location simple. In the field also were NGCs 4722, 4723 and 4748.

I knew this would not be a long observing session, with things to do on Sunday. But I finished off Coma Berenices and started tackling the few remaining targets in Corvus. So, it was a good and productive evening.

Almost forgot one of the most interesting observations of the night. It was the first - a thin crescent moon in the murk to the west at twilight. There appeared to be a bright spot sitting right on the edge of the limb just north of the lunar equator. In the telescopes, there was no bight spot... but there was a large crater with a raised internal plain. Cool sight, I wonder if we were seeing that flat crater interior reflecting light brighter than the rest of the crescent. There was also a thought later at night that a supernova could have been picked out - a new one - the observer was using SkyMap and I was using The Sky, neither of our programs showed the bright star very close to this Herschel 400 galaxy...

Great night. Too bad more people weren't there. I was saying that even when it looks iffy, you stand a chance of getting in some observing, and certainly a chance of getting skunked. We got lucky and had a fun night. But, if you don't go, you are guaranteed to get skunked. And that stinks.

So, how were things at the Peak and other sites?

Tuesday, April 5, 2005

Wildflowers from Coe

Springtime has arrived at Henry Coe State Park. Wildflowers are beginning to appear - notably the California Poppy, sprouting up along the roadsides and paths, like clusters of galaxies in the spring sky...

It was an excellent night at Coe. Four observers were present bringing 20", 18", 15" and 10" Dob, and a nice pair of Vixen long focal ratio mounted binoculars. I arrived at 7:30 pm, in time to watch the sun set over the coastal peaks and get my equipment set up. The sky was very clear and the steadiness of Saturn gave us hope for good clean star images, which is how things turned out for most of the evening. The parking lot was dry and without dust, and there was no breeze at all until around midnight, and even then it was only slight. Transparency was excellent. In the 20" I viewed detail in the Ghost Of Jupiter (NGC 3242) that I've never seen before, and M51 that rivals the best views I've ever had. Too bad the next morning was a work day, or I'd just now be getting to sleep instead of writing this report.

The view of the night was the Ghost of Jupiter. M51 was amazing, but I've had views similar to last night's in the 30" at Fremont Peak, and at times at high elevation from Mount Lassen. The Ghost of Jupiter usually appears to me as a very bright large planetary disc with little detail. Just a bright ball. In the 20" at 280X there was tons of detail. A small central dark disc with the central star - a pinpoint - popping in and out. A bright ring around the dark disc, then a grey diffuse oval around the bright ring... and... further out, a large faint envelope of nebulosity. This was without a filter.

My personal observing program was to continue on the Herschel 2500 list. I went observing last night because springtime is the big "hole" in my list - the weather is usually so sucky, all I have left are springtime constellations - Coma Berenices, Virgo, some of Hydra and Corvus. Coma was already up decently in the east at astronomical dark. I also should note that this was my first night out since the trip to Chile. I think I prefer Orion and Leo upside down! ;-) And, while mentioning Chile, there was talk about a return trip next year with a 20" and 18" Dob. Is it unsightly to salivate while dreaming?

Coma Berenices has some very good stars to hop from. My 18" Obsession is equipped with a 10x70 Celestron finder and a Rigel Quickfinder. We were talking about setting circles, but so far I've resisted adding Sky Commander to my setup. The eyepieces I used were all Naglers, the 20, 12 and 7.

I am at the dim end of the list in Coma - I began with NGC 4923 - a magnitude 14.67 round galaxy with a close companion - NGCs 4921, 4919 and 4911 (there are many other galaxies in this rich area). The four galaxies were all very faint in the 20 and 12 Naglers. I compared the surface brightness (SB) of 4923 and 4921 - and the dimmer magnitude 4923 had about the same SB. This galaxy field is easy to find, just west of the naked eye pair of mag 4.5 stars 41 and 43 Comae Berenices, located between Arcturus and Berenices Hair.

NGC 5004A was next, and nearby. The scope only had to be moved slightly, to the west of 43 Comae Berenices. This galaxy is very faint and located very close to a mag 12 star. The galaxy is non-descript, except for an elongation NW to SE. NGC 5004 is in the same field of view (FOV). It is bright, has a noticeable central concentration with a stellar core that is at the edge of visibility. I enjoyed locating these galaxies as there were some nice finder stars to their NE that are at the edge of the FOV about 23 arcminutes away. NGC 5004 is mag 13.89 type SO, 5004A (designated 5004C in NED) is a mag 14.6 type SB.

Just under 2 arcminutes to the NW sits the nice pair of galaxies NGC 5056 and NGC 5057. My target was 5056. These are a pretty view, sitting just outside the short leg of an obvious right triangle of bright stars. Both objects seem extended N/S, and 5056 is significantly larger than 5057, and more extended. 5057 has a bright central region . 5056 is a mag 13.7 type Sc, 5057 is mag 14.04 and SO.

I was surprised that my next target went unnoticed, in the same FOV as 5056 and 5057. NGC 5065 is NE of the other pair, just outside one of the corner stars of the right triangle. Once I knew where to look, it was an obvious galaxy. Combined with the stars of the triangle and other galaxies, I found they created a nice visual arc. 5065 seemed to be oriented E/W and was the largest of the three galaxies in the FOV. It was hard to tell if it was round, as it seemed to have some internal darkening that caused me to guess it might be disrupted or a face-on spiral. There was a very faint star "in" the galaxy embedded its northern section. NGC 5065 is mag 14.20 and type Sd.

While observing, some lost campers drove by, sat with their car lights on at the entry gate, so we hid behind our trucks, waiting for them to make their move. Eventually they drove off, up to the campground. They would return later and get a sky tour in the 15" Dob. Two of the observers commented how little traffic there was at Coe... this was their first time observing from the site. Well, it was a Tuesday night, but yes, it is less trafficked than Fremont Peak (which is what it was being compared to). There were also comments that Coe is as dark as the Peak. Certainly the city lights to the NW are there, but positioning your vehicle properly and looking to the south and east, it can be pretty dark, especially when fog blankets the cities. I did a limiting magnitude count in the Bootes - Coma triangle - at 2 am. - I can safely say it was mag 6.6, and maybe mag 6.9. What was cool was the transparency!

Just a degree south of NGC 5065 is the bright roundish galaxy NGC 5089. In the same FOV is UGC 8377, obvious off a string of stars to its SW. 5089 is a type Sb at mag 14.02, UGC 8377 is a round type E at mag 14.62.

I next moved 14.5 degrees south, using Arcturus and Murphid (mag 2.6 Eta Bootis) to point me to NGC 5180 and NGC 5172. These galaxies are both bright (mags 13.96 SO and 12.63 SAB) and have a mag 7 star nearby. 5180 is kind of trippy, I had to call a couple of other observers over to peek at it... it looked like a dim globular rather than a galaxy, but it turned out there were three very dim stars in front of the galaxy, giving it the appearance of having stars visible in the object. The stars would blink in and out, so we began calling it the Blinking Galaxy. 5172 appeared to be a larger disrupted galaxy or face-on spiral. 5180 was a small amorphous haze amid the dim stats...

One of the happy accidents that occur star hopping, rather than using a goto or DSCs is running into unexpected objects. When hunting for NGC 4529 (this one took for-ever!) I found that 24 Comae Berenices is a beautiful double star - sapphire blue and a creamy ivory gold, nearly equal magnitude. Worth the trip!

I finally did find NGC 4529. Hopping in the Coma Cluster is tricky! There is a dim "V" of running E/W and N/S with its apex to the SE of the galaxy. The galaxy was extremely difficult, I could pick it up only about 20 percent of the time. It was nothing more than a very dim haze with several very faint stars nearby. This galaxy defines the term "lumpy darkness"... It is a small slash at mag 15.0, type Sc.

The next object was just over eight degrees to the NNE, back near where I started at 41 and 43 Comae Berenices. I was after NGC 4789A, aka UGC 8024 - a mag 13.94 type IB galaxy with a very low SB. NGC 4789 was quite easy to pick up to its SE. But the dimmer "A" galaxy was visible only as a large haze about 33 percent of the time, nicely tucked in between four dim stars. I had estimated its size as twice that of 4789 and elongated NE/SW. This one is a toughie!

45 arcminutes to the NE I found NGC 4816 - easy, bright, elongated 3x2 NNE/SSW. Visible in the same FOV was MCG5-31-13. 4816 is a mag 13.8 type SO, the MCG is mag 15.6! type E. Woohoo! A dim one!

By this time it was getting late and cold. I had spent way too much time hunting for 4529, a good lesson to kick such problems to the curb, move on, and try again another night. The breeze was just beginning to kick up and I thought of heading home. But, it was such a good night, I pressed on for a few more targets....

NGC 4840 was easy, and actually in the same FOV as 4816 (but at the very edge of the field). It was very near the brighter galaxy NGC 4839. I also saw NGC 4842A, but not the B component, both located just off 4839. I did pick up MCG5-31-37 in the same FOV. 4816 is a mag 14.7 type SAB, 4839 mag 13 type cD, 4842A mag 14.9 (no type designated) and the MCG mag 14.9 type SB.

A half degree to the NE was a real treat - I was going for NGC 4869 and discovered it is in a rich galaxy cluster. In my FOV I counted seven galaxies easily. I'm sure there would be more, but the breeze had begun to deteriorate the seeing, and stars were starting to look like small round galaxies or planetaries. Using The Sky I can see that with a mag 15 limit, there would be probably 30 galaxies in the 47 arcminute field of my 20 Nagler. This cluster will be on my list again in the future.

I was about to tear down and decided on one more object (this sure sounds kid-in-the-candy-store-ish!) It was a tough one. NGC 4911A was fortunately in the same FOV as the prior galaxy, so it was easy to get to. Seeing it was the hard part. This one is a mag 15.30 type SO and only 0.53 x 0.26 arcseconds (which helps increase its surface brightness). It appeared to be a small spike perpendicular to NGC 4911 to its S. There is a nice image of this small "spike" among many of the galaxies in the rich cluster I mentioned, at:

That was it for the night. It was 2 am when I pulled out of the lot. It was an easy drive home, and I was very satisfied after a great night of observing. I plan to take advantage of other mid-week opportunities during the spring. Wildflower season goes by too quickly.