Monthly Summary 2 (mid-April/mid May 2013)

     The clear sky gods were not around much this past month, though now that the moon is waxing they seem more abundant.  I have had a disappointing spring session, though I've tried to make the most of the few decent nights we did experience.  Most disappointing has been my initial season observing all of the NGC objects in Leo, along with a healthy selection of double stars and such.  And once Leo was too far west, I had hoped to get a good start on Bootes.  Oh well, at least the planning is done and next year I should be able to start right back in again with Leo.  There is still a chance that I can score a few more galaxy hits there near the end of this month.

     Here are the details.  All 16 new NGC objects logged this past month were galaxies.  15 of them were in Leo, and 1 was in Bootes.  A few were large and spectacular, some were reasonably bright and interesting, and several were so faint they could barely be seen with averted vision.  As it was last month, the highlight was the Leo Triplet, consisting of M 65, M 66, and eg 3628.  Last month I was able to sketch and log M 65, so this month M 66 and eg 3628 seem new, even though they have been observed many times before.  Until the sketch and notes of an object are entered into my observing logbook, I do not consider it as seen.  Two other galaxies within easy star hop of the triplet also provided highlights for the month.  Eg 3593 is large and bright, and lies within a notable star pattern, making it easy to find again once it has been located for the first time.  Eg 3596 is a bit north and considerably fainter, though also large.  The galaxy has become a marker for me for good seeing.  If this round object can be easily seen, then the hunt for much fainter galaxies is on.

     Another trio of galaxies provided me with a few nights of thrills.  This group marks my third triplet in Leo, even though I have barely begun my explorations there.  Egs 3607 and 3608 are a stunning and close pair, very bright and quite large in a 12".  Visually they are mag. 9.9 and 10.7, respectively.  3607 is considerably brighter, and has a bright inner core.  Its nearly circular shape is offset by a slightly oval 3608, an object that is also considerably smaller.  The third member is the smallest and faintest, but is fair game for an 8" mirror or higher.  Eg 3605 is just south preceding 3607, perhaps a bit more oval than 3608, though similar in shape.  An interesting group of faint stars is just south following eg 3607, including a close, faint double star.

eg 3605 is the smallest of these three galaxies in Leo.

eg 3607 is largest and brightest.  eg 3608 also fits

into my view at 150x.  South is at the top.

Image from http://www.astrosurf.com/benoit/ngc.html

     Most of the rest are very faint galaxies, showing little detail except perhaps shape.  These include the following:  egs 2913, 2919, 2923, 2928, 2933, 3805, 3592, and 3598.

     Only one galaxy was logged in Bootes.  Eg 5490 is visually mag. 12, with a much dimmer surface brightness due to its modest size (13.7 mag.).  I was pleased with finding this one from my back deck under a 6-day old moon.  I even saw an extremely faint 2nd galaxy directly north of it, though I cannot find a name for this object.  I had been searching for 5490C, but this was not it.  Nor was it "B".  Perhaps I shall call it 5490D.  Alas, what is life without little mysteries?

     Also this month I managed a few close looks at different parts of the lunar surface, as well as a few superb views of Saturn, mostly around midnight when the air had settled down.  I also viewed a whole slew of large, bright galaxies, double stars and the wonderful globular M3 as part of my scope's computer tours (see previous blog entry for details).

     In other news, the Astroscan 4" has been sent off to Edmund Scientific in NY.  Either they will be able to clean the mirror or they will replace it.  Deb and I look forward eagerly to its return, hopefully for the next dark moon phase.

Mapman Mike

The Leo Triplet of Galaxies

     There has not been a great sky for galaxies here since April 5th.  However, the upcoming early week forecast looks good.  There have been a few nights with lots of haze, including the last few nights.  Thursday was the full moon, and Deb and I went out on the deck to watch it rise.  We also brought out some binoculars, and made a good scan of the whole of Leo, something I had not yet done.  I usually focus on one small area at a time, and am prone to lose "the big picture" as a result. 

     On Friday night we had about 45 minutes of dark sky before moonrise.  We set up our 2nd scope, the 4 1/4" Edmund Astroscan rft.  Sadly the main mirror has deteriorated to the point where we will have to send it off to Edmund Scientific to be replaced.  They will put in a new mirror and collimate it for around $140.  We recently purchased a tripod for it, as well as a red dot finder-scope.  One of the first things we looked at on Friday was M44, the Beehive Cluster.  Too large to fit into the field of most telescopes, the Astroscan was made for just such a task.  With the 28 mm eyepiece giving 16x, the cluster was quite impressive even in twilight.  Next, we scooted around some of the brighter stars and doubles in Leo, easily splitting Gamma at 50x (18 mm eyepiece with 2x barlow).  Gamma is one of the finest doubles out there, mag. 2.6 and 3.8, separated by 4" of arc, with both stars appearing golden yellow.  In the 12" it looks like a pair of headlights approaching, but it is still lovely in the 4".

     Last night, with about 90 minutes of dark sky before moonrise, we set up both scopes.  The evening had plenty of hazy clouds.  They went away for awhile, but then returned.  Despite this I was able to officially log M66 and eg 3628.  I have observed the Leo Triplet nearly every clear night for the past month and a half, and I have yet to tire of any of the three objects.  Last night I was able to use 200x on M66 and M65, getting bright, crisp views whenever the haze would move on.  It was easy to hop back and forth, even at high power.  This remarkable pair of galaxies was not noticed by Messier when a comet passed through the field in 1773.  According to Mechain, who did log them, the comet was probably too bright.  Imagine a comet passing through this area that blotted out those two bright galaxies!

     Noting the differences between the two Messier objects makes for good observational training.  M65 is more elongated, not quite as bright, and has a barely visible (in the 12") dark lane down its east edge.  This is more an impression than an easily observable feature, but I have seen it more than once.  M66 is the brighter galaxy, slightly less elongated, and has a blazing core that lies not in the center, but just a bit to the north.  This galaxy will take any magnification and still appear bright.  They both fit into my 100x field, and I will continue returning to them throughout the season.

     NGC eg 3628 is probably, after M31, one of the largest galaxies I have ever seen.  It is viewed edge-on, and is extremely elongated.  Using averted vision and 100x or 120x, it just goes on and on and on.  Almost featureless in the 12", other than more brightening near the middle, it still makes a wonderful site.  The darker the sky, the better this one appears, but even through haze I was able to get decent views.  NB: In March 2014 I easily observed the dark lane running all across this galaxy.  It was a superior observing site and a very good sky.

     Two other smaller galaxies appear near the triplet, and one of them is very much worth seeking out.  Immediately preceding M65 and M66 are three brighter stars in a straight N/S line.  Star 73 is the one in the north, with two slightly fainter ones due south.  Eg 3593 immediately precedes the middle star, and should be easily visible in an 8" scope.  It is elongated E/W, and pops into view more readily than eg 3628.  It is about 1/3 the size of that galaxy, but is a very enjoyable sight in the 12", its bright core easily seen.  With averted vision and 100x, the full extant of the arms can be seen.  If I cannot see this galaxy on a given night, then I know the sky is a bad one.  Lately it is my first test for a quality galaxy sky. 

     A fifth galaxy is also nearby, and makes an excellent final test for good skies.  Eg 3596 is the faintest of the five, lying north of the three stars just used to find eg 3693.  It is south of Theta, also called star 70.  This, too, is a big galaxy, oval but much harder to see than the others.  If this one pops up right away at low power, I know I have an excellent night of galaxy hunting ahead.  Last night it only appeared as a threshold object at medium-high powers.

     I have yet to officially log these fourth and fifth galaxies, though I have sketched eg 3693.  They will both be logged on the next good night.  All five galaxies are an easy star hop from one another, and I now know my way around this area extremely well.  If you have not visited these galaxies yet, I can highly recommend them.  Telescopes of 8" or higher will offer rewarding views, especially if you go back often.  In the 12", even from suburban skies, they are quite stunning and unforgettable.

Mapman Mike