Saturday, 27 January 2018

#117: Winter 2018

 The beginning of a new year is usually a good time to both reflect on the past year and its achievements, and to look ahead and set some reasonable goals for the upcoming year.  In 2016, I made it my goal to get out and observe on every clear night I could.  For my galaxy observing I require nearly pristine, dry skies.  So to compensate for Essex County skies, I needed many different types of objects that could be observed at Hallam if under less than perfect conditions.  It was a good year for planets; I also did some remarkable double star work, and I even got back into lunar observing.  I managed to observe on 72 different nights in 2016.  By comparison, 2017 saw me under the stars only 34 times.  Had my goals changed?  Not by much.  I missed the April dark sky session because of travel plans, and ended up missing three good nights as a result.  Even so, the weather last year was often less than ideal for astronomers.  Was it just one of those years?  I hope so.  If I could make one wish upon a falling star, it would be for more frequent clear nights (not counting those beautifully clear nights around a full moon!).

While January is a great time to look back on the year’s notes, and to plan new observing goals, it is often a terrible time to be outside setting up a big scope.  The nights in deep winter are often more suitable for naked eye and binocular observing than for any telescopic work.  It is also a great time for some armchair astronomy.  I like pulling out my old Olcott book and glancing through it near a warm indoor wood fire.

William T. Olcott, in his Field Book of the Skies, divided the night sky into seasonal work.  His winter constellations include Taurus, Orion, Lepus, Canis Major, Monoceros, and Eridanus.  Using a telescope I have completed observations of   NGC and other deep sky objects in Taurus, Lepus, and Monoceros.  My clipboard is now prepared for Orion, and includes a grueling list of 178 winter objects.  However, before trying to navigate outside with freezing toes and fingers using my 12” Dob, it is always a good idea to explore some of the constellation with naked eye and 8 x 35 binoculars first. 

It is not surprising how many sky-watching novices think that stars are only white.  When colourful stars are presented, it can be an astonishing revelation for them.  Comparing Rigel and Betelgeuse with the unaided eye, a difference in colour is apparent.  However, using binoculars the difference is much more astounding.  If you are showing the orange and red star to a beginner, you might also make mention of Professor Michelson (1852-1931).  A number of interesting facts can be mentioned regarding this American physicist (born in modern-day Poland).  He was the first American to win a Nobel Prize in the sciences, for one thing.  His main work was in refining measurements of the speed of light.  However, it was his work in interferometry that brings his name into Olcott’s book, in conjunction with the star Betelgeuse.  This star became the first one, other than our Sun, to have its diameter measured (in 1920-21). Michelson’s interferometer design is still in use today at major observatories. Incidentally, Betelgeuse is 1.64 billion km in diameter. Our sun, by comparison, is 1.39 million km.  But wait, there’s more!   In popular culture, no less a man than Ben Cartwright helped Michelson get his career started.  In the “Look To The Stars” episode of Bonanza, broadcast in 1962, the 16 year old budding scientist (played by actor Douglas Lambert) is aided in his struggle for admission to the US Naval Academy by the Cartwrights.  Michelson did live in Nevada at that time in his life!  The episode can be watched on Youtube.

Now it’s time for a look at the Great Nebula.  Though it presents a distinctive mystery to the naked eye, in binoculars the mystery at least becomes a more beautiful one.  I have trouble with the trapezium star in hand-held binoculars, but with a steady hand the area makes for fun sweeping.  Olcott suggests that it was a Swiss Jesuit by the name of Cysatus, in 1618, who made the first report on the nebula.  His full name was Johann Baptist Cysat (c. 1587-1657), and his main interest as an astronomer was in observing comets.  He was one of the first to make astronomical and scientific use of a telescope.  Even in 1804 his descriptions of comets were still among the best available.  Here is Cysat’s brief description of the Great Nebula:

Another of these phenonmenon in the heavens is the congeries of stars at the last star of the Sword of Orion, for there one can find a similar congestion of some stars in a very narrow space, and all around and in between the stars themselves is a diffused light like a radiant white cloud.”

We actually suspect now that the first notated observation was in 1610, by Nicholas Peiresc, though he was silent on the nebula afterwards.  Surprisingly Galileo did not mention it in his early observations of 1609 and 1610, though he did map the stars of Orion.  Over the years hundreds of descriptions have come down to us.  I will leave this topic with Olcott’s own description:

“…The nebula is a stupendous mass of gas in a state of violent agitation, a gigantic whirlpool.  Even when viewed with an opera or field glass the star Theta Orionis appears to be enveloped in a haze which indicates the presence of the great nebula which is a glorious and wonderful sight in a large telescope.  Words fail to describe its beauty.”

Oddly enough Olcott goes on to describe the Horsehead Nebula in the unaided eye and field glass section of his Orion section.  The Belt stars, where we will finish up our cold winter’s night viewing, point in one direction towards Aldebaran in Taurus, and in the other down towards Sirius in Canis Major.  There is fine sweeping in those areas, too.  From bottom to top the belt stars are Alnitak, Alnilam, and Mintaka, all around 2nd magnitude.  These stars have attracted attention since the dawn of human sky gazing.  The Orion correlation theory holds that there is a correlation between the three largest Egyptian pyramids and the three belt stars in Orion.  That itself is worthy of some future Aurora article, and certainly worth a casual mention at a winter star party.

Wishing everyone clear skies in 2018!
Mapman Mike

Tuesday, 28 November 2017

#116 Hercules NGC Project Part 10: Uranometria Charts 35, 34

If you have been following my progress on the reporting of all the NGC objects in Hercules (along with a few IC galaxies, and objects from other catalogues), you can see that it was an enormous undertaking.  Consider that my temperate zone location amidst The Great Lakes of Canada and the USA means that clear nights are pretty rare.  In a good two-week session there might be 3 nights suitable for faint galaxy work.  I am just finishing up the November observing session, and it has been one of the worst in recent memory.  I've only had 3 hours of good skies, and managed a mere trickle of progress in Cetus.  This is the final report on Hercules.  I have finished observing Pegasus also, but at the moment I don't have the time or energy to report on it here.  But it will come.

Uranometria Chart 35 

eg I. 1144:  1' x 0'.6:  Vis. 13.5; SB 12.8:  This galaxy is at the east end of Bootes and west edge of Hercules.  Spotted at 136x, it was also observed at 187x and 250x.  It is small, pretty bright, and very oval.  Although easily visible it is a ghostly object, best seen with averted vision.  200x gives a decent view also.

eg 6013:  1'.3 x 0'.8:  Vis. 13.6; SB 13.5:  Spotted at 136x, it was large, faint, and elongated.  187x gives a good view of the oval haze.  It is pretty large.  250x shows a brighter center, but the rest is fading.

pn 6058:  40";  Vis. 12.9; SB 13.9:  Viewed previously with the 8" from the back deck at home in 1992!  It was not that impressive back then, and I did not have a Skyglow filter.  With the 12" I viewed it at 60x and on up to 375x.  Without the filter the central star is easily visible, but the nebula is not as impressive.  I had lovely views at 250x and 272x with the filter on.  It seems oval at high power, and somewhat mottled.  It is a very bright object, evenly lit except for the mottling effect.  This makes a nice change from faint galaxies.

eg 6154:  2'.1 x 2':  Vis. 12.7; SB 14.1:  Located at 100x using averted vision.  At 136x it is much easier to see.  It is pretty large.  187x gives a good view.  The center is now brighter, and averted vision begins to show its full size.  250x shows a stellar core amidst the bright central area.  Averted vision gives good glimpses of a much larger object than seen with direct vision.

eg 6155:  1'.3 x 0'.9:  Vis./SB 12.3:  Spotted at 60x.  At 100x it was oval and bright.  Located just north preceding double star Cbl 64.  At 136x the galaxy is very faint, very oval, and very close to the double (9.5-12.4/31").  At 187x 6155 becomes pretty bright, large, and oval.  At 250x and 272x views are still very good, especially with averted vision.  There is a stellar core.

eg 6159:  1'.4 x 1':  Vis. 14.2; SB 14.4:  Easily seen at 136x (it was a fine night), the galaxy was a large oval, not too faint.  At 187x it is pretty large, moderately bright, and shows a stellar core.  Views improve at 200x, with many faint stars in the field.  Afterwards it could be seen at 100x.

gc 6229:  4'.5; Vis. 9.4; Br. * mag. 15.5:  Spotted at 60x and 100x, it forms the apex of a stunning triangle with two bright white stars (Mag. 8, 8.5).  The texture of the globular cluster is mottled at 100x.  AT 187x a few outliers are resolved.  At 250x, 272x, and especially 375x, resolution is fair.  There are clumps and knots of stars near the uneven centre.  This is a very bright object, and pretty large.  A 16" scope would likely resolve it more fully.

eg 6239:  2'.6 x 1'.1:  Vis. 12.4; SB 13.4:  Spotted at 60x, it was large, very elongated, and ghostly.  100x and 136x give much better views, and it is now larger and brighter.  Averted vision shows the full extent of the galaxy.  At 187x and 200x it continues to be very bright, especially the central area.  250x gives the best view.  The elongation runs E/W.  There is a very faint star north.  In the 8" from Lake Penage, this was a tough object to locate.

eg 6241:  1' x 0'.8:  Vis. 16.2; SB 15.8 (elsewhere it's 15.2 and 14.8):  The first set of specs given came from Uranometria.  They are obviously wrong by a magnitude.  The 2nd set given in brackets comes from the now defunct website "Night Sky Atlas."  Celigman gives mag. 15; DSO gives 14.2.  Anyhoo, using a hand-drawn pinpoint map (using DSO Browser) this was an easy object at 136x, and very obvious at 187x.  It was round, pretty large, and an easy (!) object to locate.  It lies in a very dark region of the sky, with no nearby bright stars.  At 200x and 250x it is a ghostly but decent object to observe.

Uranometria Chart #34 

eg 6279:  1'.1 x 1'.1:  Vis./SB 13.6:  A near twin to 6283 (see just below), they make an interesting contrast with one another.  Spotted at 100x, even at 136x I needed averted vision to properly see it.  It is a bit fainter than 6283, no doubt because of the brighter star field.  Views are better at 187x.  The galaxy is located south preceding a pair of fairly bright stars.  250x shows a bright center, much smaller than the whole.

eg 6283:  1'.1 x 1'.1:  Vis./SB 13.5:  Spotted at 100x, it resembles a ghostly planetary nebula.  Views are good at 136x.  The galaxy is round, large and pretty bright.  At 187x views are much better, with a bright middle section showing clearly.  Views are still good at 250x.  A double star is south preceding, with a faint companion.

eg 6301:  1'.8 x 1'.1:  Vis. 13.3; SB 14:  Viewed at 100x, 136x, and 187x.  It precedes a star of mag. 11.5.  The galaxy is small and very ghostly, likely only the central area is seen.  The envelope is very faint, and even the 11 mag. star helps hide it.

eg 6311:  1'.1 x 1':  Vis. 13.5; SB 13.7:  The galaxy can be glimpsed at 100x, but it is much easier to see at 136x.  It sits between 2 bright stars just following an imaginary line between them.  187x shows it as round, pretty large, and still quite a good object for visual observation.

eg 6312:  0'.7 x 0'.7:  Vis. 14.2; SB 13.3:  I took a stab at this one and got lucky, spotting it at 136x.  It was pretty fair at 187x, but small and faint.  250x shows a stellar core, but the galaxy overall is still small and faint.

eg 6313:  1'.3 x 0'.4:  Vis. 13.9; SB 13:  Spotted at 136x, following a faint double star.  At 187x it is an obvious slash.  Views are very good at 250x.  However, the best view was at 272x!  Here it was bright, very extended, appearing as a long slash with a wider middle.

eg 6320:  1'.2 x 0'.8:  Vis. 13.9; SB 13.7:  This very faint, very oval galaxy was picked up at 136x.  A very faint star is on the south end.  Viewed at 187x, 200x, and 250x.  Though not small, it is somewhat tricky to spot.

eg 6323:  1'.1 x 0'.4:  Vis. 13.9; SB 12.9:  Spotted at 100x and 136x, it was a very ghostly, wide slash.  Observed well at 187x and 250x, it was faint but easy to view with averted vision.  It is just south following a faint star.  The galaxy is extended nicely, but more oval as opposed to a longer, skinny slash.  It is just north preceding eg 6329.

eg 6327:  0'.4 x 0'.4:  Vis. 14.9; SB 12.7:  29 was spotted at 100x, being large, round (though
eg 6329:  1'.8 x 1'.8:  Vis. 12.8; SB 14.1:  flaring), and pretty bright.  Up to 250x was used with good results, showing a bright  galaxy.  It has a bright central area.  27 was spotted at 136x with averted vision, between 2 faint stars.  Though tiny, it was easy to view at 187x and 250x.

eg 6332:  1'.6 x 0'.8:  Vis. 13.6; SB 13.7:  Noticed at 100x, it was oval and pretty faint.  136x and 187x provide very good views.  It is obvious, though fainter than eg 6329.  It is very elongated, pointing towards the brightest star in a nearby small framing asterism.  6329 is immediately preceding, and a tiny bit north.  Both can be seen together at high power.

eg 6336:  0'.9 x 0'.7:  Vis. 13.2; SB 12.9:  One of 5 NGC galaxies in the M 92 group.  It was spotted at 100x with averted vision, being faint, small and round.  It is much easier to see at 136x and 187x.  It is located just north of a mag. 10 star.  At 250x the galaxy is fading, though still quite visible.  It now appears slightly oval.

eg 6339:  2'.9 x 1'.7:  Vis. 12.7; SB 14.3:  Viewable at 100x and 136x, it is very large and very faint.  It is really faint at 200x, but large and oval, showing a somewhat brighter center.

gc 6341--Messier 92:  14';  Vis. 6.5; Br. star 12.1:  This is a fabulous cluster in an 8" scope.  Anything bigger is a wonderful bonus!  Way back in the day of my Tasco 4.5" mirror, I use to yearn for the capability to resolve globulars into tiny stars, trying to imagine what the effect would look like.  I could not have imagined it in my wildest dreams!  In the 12" at 60x stars were resolved all across the object.  At 100x, M 92 is not as large or rich as M 13, being about a third smaller and a magnitude fainter.  However, the brightest stars are almost as bright as in M 13.  Though there are fewer stars, and they are more scattered, 136x still offers a superb view of a breathtaking and rich object.  Many outliers are resolving, in addition to stars right in the core.  At 187x and 200x the outlier area is rich with resolved stars, especially to the north and south of center.  The effect is similar to wings on a moth with a very bright head.  250x gives an outstanding view, with core detail emerging.  At 272x I had really good views, especially of the wings.  At 375x the core has broken into two halves, north and south, and is mostly resolved.

eg 6343:  1'.1 x 1'.1:  Vis./Sb 13.9:  Though spotted at 100x, this galaxy was much better at 136x.  It is round and has a bright center.  At 187x is it now moderately faint, but still easy to see.  It lies south of 2 bright stars that point in its general direction.

eg 6348:  0'.7 x 0'.6:  Vis. 14.4; SB 13.3:  48 was spotted at 187x, south preceding 50.  It is very
eg 6350:  1' x 1':  Vis. 13.2; SB 13.3:   small, very faint, and round.  50 was an easy object at 100x, being round, bright, and pretty large.

eg 6363:  1'.1 x 0'.9:  Vis. 13.3; SB 13.2:  The final galaxy I saw in my comprehensive NGC study of Hercules!  It was a pretty "normal" galaxy, too.  Suspected at 100x, it was confirmed at 136x.  It is seen well at 187x, being oval now with a stellar core.  A faint star is south following.

I. 1262:  1'.2 x 0'.6:  Vis.13.7; SB 13.3:  Both galaxies were observed at 136x, 187x, and 250x.    
I. 1263:  1'.7 x 0'.7:  Vis. 13.7; SB 14.2:  They both fit into all three eyepiece fields.  They are both faint, but 62 appears both brighter and larger.  63 is a very faint and long oval, immediately preceding a pair of bright stars.  62 is located just south of 63.

I. 1265: 2' x 0'.9:  Vis. 12.3; SB 12.8:  Spotted at 100x and 136x, it is large, faint, and oval.  Seen well with averted vision, it seemed best at 187x.  Here it is quite large.  200x shows it steadily with direct vision, though faint.  It is beginning to fade in this range.

eg 6443:  1'.2 x 0'.5:  Vis. 13.8; SB 13.1:  Spotted at 100x and 136x with averted vision.  It is cigar shaped, an elongated but wide slash.  It is pretty faint.  At 187x views are considerably better, though still using averted vision.  250x shows the galaxy steadily with direct vision, though it is pretty faint.  It sits amidst a triangle of very faint stars.

eg 6524:  1'.3 x 1':  Vis. 12.8; SB 13:  Spotted at 100x, it was oval and bright at 136x.  187x increases the size and brightness.  The galaxy is preceding a group of stars in the form of a backwards check mark.  A bright center is noted.  250x provides good, steady views, now showing a stellar core, along with a bright middle.  It is also pretty large in this range.

eg 6560:  1'.2 x 0'.8:  Vis. 13.6; SB 13.4:  First spotted at 250x, south of a 10.4 mag. star with a bright companion.  It just precedes a bright asterism of stars.  Once located, views were also good at 187x and 200x.  It is oval, pretty large, and pretty faint (I only had fair transparency at this point of the night).  It was a poor object at 136x, after viewing it at high powers.

eg 6582:  0'.6 x 0'.6:  Vis. 13.9; SB 12.9:  Again this was located first at 250x, after a pretty good educated guess as to its exact location.  It was then observed at 187x, then lastly at 136x.  Though very small at lower power, it was not too small for observing at 187x and 250x.  It is round, very ghostly, and averted vision gives the best view.

This concludes my NGC observing notes for HerculesNext summer I will begin to view several pages of double stars here, as well as search for some UGC and IC objects.  Still to come in this series is the complete guide to Pegasus NGC objects, whenever I get the time and energy.  After that, I will likely be finished Auriga and will report on that.  In the Spring I will conclude observing the NGC objects in Bootes, and then report on those.  I hope you have enjoyed your visits.  If I have omitted an NGC object from the Uranometria charts, please drop me a line to let me know.

Clear skies!

Mapman Mike  

Monday, 20 November 2017

#115 Hercules NGC Project Part 9: Uranometria Charts 50, 49

Uranometria Chart #50

Note that the right hand side of the chart is dealt with on the Chart 51 page.

oc DoDz 6:  3'.5; 5 *s; Br. * mag.8.8:  Observed at 60x and 100x.  It is a 5-star asterism, and non too exciting.

eg 6255:  3'.6 x 1'.5:  Vis. 12.7; SB 14.4:  Far from being a showpiece object (and far from being visual mag. 12.7), this one is fun to locate anyway.  It seems closer to mag. 14, it's large size likely makes it too faint for smaller apertures.  In the 12" it was seen at 100x.  It is very large, very oval, and very faint.  At 136x the center is brighter, and it is even larger overall.  At 187x it is fading, but a few stars involved can now be seen.

eg 6257:  0'.8 x 0'.3:  Vis. 15.1; SB 13.4:  These really faint galaxies can wear you down if they are not spaced out with brighter objects.  This was my 2nd one of the night, after only 3 objects viewed.  Luckily, a pinpoint hand-drawn map got me right to the scene, with a northwest/southeast line of 4 stars pinpointing the location.  Glimpsed at times with averted vision at 250x and 272x.  It is very faint and elongated.

eg 6274:  0'.6; 0'.5:   Vis. 13.8; SB 12.3:  Using a detailed, hand-drawn map, the main galaxy was
eg 6274A:  0'.7 x 0'.2:  Vis./SB ??:   spotted at 136x.  It was round and not difficult to see.  Views were decent at 187x.  At 272x, 74A was glimpsed as a tiny add-on, non-stellar, with averted vision.  It seemed an extension to the south following end of the main galaxy.  I never would have noted this unless I knew exactly what I was looking for beforehand.

eg 6282:  0'.7 x 0'.5:  Vis. 14.4; SB 13.1:  Located south following eg 6274, I used the same detailed chart as above (I use dso-browser).  136x actually gave a pretty good view.  The galaxy is oval, faint, but distinct.  A very faint star is  following.

eg 6330:  1'.4 x 0'.5:  Vis. 14; SB 13.5:  Viewed at 136x and 187x, the galaxy is small, faint, and very oval.  I managed a sketch, though.

eg 6349:  0'.8 x 0'.2:  Vis. 14.3; SB 12.2:  After some searching I located 49 at 136x.  At 187x both
eg 6351:  0'.2 x 0'.2:  Vis. 15.2; SB 13.5:  galaxies can be seen!  At 200x and 250x a very small, faint slash can be seen, with the smaller haze just following, mingled with a faint star or two.


eg 6364:  1'.5 x 1'.2:  Vis. 12.9; SB13.4:  Viewed at 136x, 187x, and 250x.  The galaxy has a bright, stellar core.  The envelope of haze surrounding it is small and quite faint.  There is a nearby faint star, north.

eg 6367:  0'.8 x 0'.7:  Vis. 14.2; SB 13.5:  Conveniently located near a mag. 8 star, it was glimpsed at 100x and showing a stellar core.  Transparency was improving!  It was small but pretty bright at 136x.  187x shows a small, round, and pretty bright galaxy.  250x with averted vision shows it larger now, but fading a bit.

eg 6433:  2' x 0'.5:  Vis. 13.3; SB 13.1:  Another good guess showed this one as a long slash, and pretty faint.  At 136x it is still a weak object.  187x shows a large, very elongated galaxy with a brighter, wide middle.  250x gives very good views with averted vision.  At 272x the galaxy is long, though starting to fade.

eg 6446:  0'.7 x 0'.6:  Vis. 15.2; SB 14.1:  47 was spotted at 100x, being oval, housing a bright
eg 6447:  1'.6 x 0'.9:  Vis. 12.8; SB 13.1:  middle, and showing a stellar core.  187x gives a good view with averted vision, and 46 can now be glimpsed preceding the main galaxy.  It was quite small, faint, round with a stellar core.  Both objects were best at 200x.  A triple star system south following was noteworthy, but very faint.

eg 6485:  1'.5 x 1'.4:  Vis. 12.9; SB 13.6:  Spotted at 136x, south preceding a 9.5 mag. star.  187x shows a bright object, pretty large, with a stellar core.  Though listed as round, it appears to flare to oval with averted vision.  250x shows a very bright center.  It is large and now looking pretty round.
eg 6486:  0'.8 x 0'.8:  Vis. 14.3; SB 13.9:  87 is easy to spot at 100x, and 86 pops out at 136x.  Both
eg 6487:  1'.8 x 1'.8:  Vis. 11.9; SB 13.1:  galaxies are seen well at 187x and 250x.  There are stellar cores on both.  86 is noticeably smaller and fainter, but still quite easy to spot with averted vision, in the same field with 87.

UGC 11017:  1'.2 x 0'.7:  Vis. 13.9; SB 13.6:  Located without difficulty at 187x, it is large, oval, and pretty bright with averted vision.  It is located just following a mag. 10 star, and precedes eg 6486 and 6487.

eg 6504:  2'.2 x 0'.5:  Vis/SB 12.6:  Spotted at 60x!  There is a stellar core seen at 100x, and the galaxy is bright and elongated.  At 136x and 187x it is very large with averted vision.  It is very bright now.  It was viewed well at 250x and 272x, and even at 375x.  It is now very long, very extended, and still very bright.  Easy to locate, it lies along the base of a bright stellar triangle.  A nice catch in a 12" scope!

Uranometria Chart 49 

oc DoDz 9:   28'; 15*s:  At 60x this is a big and bright, very loose cluster, pretty rich in bright stars.  There is a milky haze in the background.  83x fills the eyepiece with bright stars, like a fireworks explosion!  This is a decent object in a 12", and likely in an 8" one, too.

eg I. 1277:  1'.2 x 0'.9:  Vis. 13.4; SB 13.3:  This galaxy is small and faint at 136x, and begins to fade away at 187x.  A pair of bright double stars separate it from eg 6575 (see below).

eg 6575:  1'.7 x 1'.3:  Vis. 12.4; SB 13.2:  The galaxy is round and bright at 136x, and very easy to see.  2 faint stars zigzag from it, pretty close.  At 187x views are very good, and the galaxy appears slightly oval.  250x also gives good views.

eg I. 1279:  2'.6 x 0'.6:  Vis. 13.5; SB 13.8:  Seen at 136x and confirmed at 187x, it appeared as a faint, large oval.  It precedes 3 stars that curve around it.  200x and 250x give occasional glimpses of a very long, faint needle galaxy.

eg 6585:  1'.9 x 0'.4:  Vis. 12.9; SB 12.5:  Located not far from Vega, which is 24' following and just a bit south.  The central oval of this galaxy was glimpsed at 100x, and appears more elongated at 136x.  Views were good at 187x, showing a bright middle and much fainter elongation.  The galaxy is located in the north preceding end of a bright north/south stellar asterism, and just south preceding a 4-star diamond pattern.

Mapman Mike


Wednesday, 15 November 2017

#114 Hercules NGC Project Part 8: Uranometria Chart 51

The Hercules NGC project kept me busy for three summers, but finally ended in 2017.  Later in the year I also completed the Pegasus observing program, which will entail another massive blog effort to report everything seen on that NGC list.  My autumn observing program now solely consists of the NGC objects in Cetus, and double stars in Cassiopeia.  I am preparing Orion objects for winter observing, and hope to continue with Leo in the early spring, and Bootes in the late spring.  I am using an Orion 12" push-to Dob.

Hercules:  Uranometria Chart # 51

eg 6161:  0'.7 x 0'.3:  Vis. 14.7; Surf. Br. 12.9:  62 shows up at 136x, being oval and pretty bright. 
eg 6162:  0'.9 x 0'.7:  Vis. 13.6: Surf. Br. 13:  up at 136x and 187x.  It is very elongated, located
eg 6163:  0'.8 x 0'.5:  Vis. 14.4; Surf. Br.  13.2:  south of 62, and further from it than 63.  63 is seen at 187x,appearing like a smaller, fainter version of 62, and immediately following (but separate).  It's like an after image.  Star 26, mag. 6.5, makes finding 61 tricky, as it is closest to that star.

eg 6177:  1'.7 x 1'.2:  Vis. 13.6; SB 14.2:  77 was seen at 136x.  It was very large, oval, pretty
eg 7179:  0'.4 x 0'.4:  Vis. 15.5; SB 13.4:  bright, and immediately preceding a bright star.  Viewed at 187x, 200x, and 250x, a stellar core is noted, plus 2 stars in the envelope, all in a line through the centre of the elongations.  A bright star north hampers views of 79, which appears stellar even at high power.

eg 6185:  1'.2 x 0'.9:  Vis/SB 13.4:  Spotted at 100x, it resembled a faint, fuzzy stellar companion to a bright star, north.  At 136x it is big and pretty bright.  At 187x and 250x it is pretty big, very oval, and the middle is much brighter.  It reaches nearly to the bright star, north.

eg 6194:  1' x 0'.8:  Vis. 13.8; SB 13.4:  Spotted at 100x, it is tiny, round and bright.  At 136x it is larger, with a very bright centre.  At 187x and 250x the galaxy shows a stellar core.  It is slightly oval, remarkably bright, but not too large.

eg 6196:  2' x 1'.2:  Vis. 12.9; SB 13.7:  My second triple group of the evening!  96 was seen at
eg 6197:  1'.3 x 0'.5:  Vis. 14.6; SB 14:  100x, and on up to 200x.  It is very bright, oval, and
eg I. 4614:  0'.8 x 0'.6:  Vis. 14.3; SB 13.4:  considerably smaller than its given size.  97 was spotted at 136x, and also viewed at 187x and 200x.  It is just north of a bright star, but only its oval centre could be seen.  The extensions were too faint.  The IC galaxy was very faint, appearing round at 187x and 200x.  These galaxies are all just south preceding Messier 13.
I. 4614 is in the north.

gc 6205/Messier 13:  20'; Vis. 5.8; Br. * mag. 11.9:  Though viewed many times previously, this was the official observation with the 12" Dob.  At 60x the globular cluster is already resolving all across its huge, bright surface.  The cluster is framed by 2 bright stars, with the north one coloured a rich yellow, and the fainter, south one white.  M 13, the 2 stars, and nearby bright galaxy 6207 (see below) all fit into the field of view!  At 100x the outer areas resolve into lines and curls of stars, giving the impression of rotation.  There are 2 notable extensions towards the white star, south, and another one towards eg 6207, north.  At 136x the massive core is breaking up, with many stars resolving at the very centre.  187x gives a superb view, nearly filling the eyepiece with stars.  The centre is dense and complex.  At 200x and 250x there are now dark spaces in the very core.  A "Z" line of resolved stars is at the very enter.  At 272x and 375x the dark lanes throughout the cluster are as interesting as the resolved stars.  A truly amazing and wonderful object!!
Can you spot eg 6207 north following??

 eg 6207:  3' x 1'.3"  Vis. 11.6; SB 13:  Undoubtedly the showpiece galaxy in Hercules.  It can be seen at 60x along with M 13 in the same field.  Though bright and large, it still appears rather insignificant next to the globular cluster.  100x shows significant elongation and a stellar core.  At 136x a few very faint stars can be seen just south.  The galaxy is seen steadier now, and larger and longer.  At 187x and 200x more galaxy shows preceding the core area than following it.  At 250x and 272x a very faint star follows the core, with another just north following it.  The preceding area of elongation appears clumpy.

eg 6195:  1'.5 x 1':  Vis. 13; SB 13.4:  Spotted at 136x, the galaxy is very conspicuous between 2 faint stars.  At 187x it shows a bright centre, with fainter parts flaring oval towards the framing stars.  At 250x it is still pretty bright and pretty large.

eg 6212:  0'.7 x 0'.4:  Vis. 14.2; SB 12.6:  Glimpsed at 187x, then again at 200x and 250x.  It was small, faint, oval, with a stellar core.  Best seen at 250x with averted vision.  It sits south of a conspicuous triangle of stars.  I used a hand-drawn detailed map to locate and identify the galaxy, based on Deep Sky Objects Browser.

Mapman Mike