Welcome to this Month’s Observing Challenge and I hope you get clear skies.
Please post your observations and or sketches of these objects in this thread. Good luck hunting down these objects.
NGC 2808: Apparent Magnitude: 6.3 Apparent Diameter: 13.8 (arc minutes)
NGC 2808 is a globular cluster in the constellation Carina. The cluster belongs to the Milky Way, and is one of our home galaxy's most massive clusters, containing more than a million stars. It is estimated to be 12.5-billion years old.
Star Generations
It had been thought that NGC 2808 - like typical globular clusters - contains only one generation of stars \formed simultaneously from the same material. In 2007, a team of astronomers led by G. Piotto of the University of Padua in Italy investigated Hubble Space Telescope images of NGC 2808 taken in 2005 and 2006 with Hubble's Advanced Camera for Surveys. Unexpectedly, they found that this cluster is composed of three generations of stars, all born within 200 million years of the formation of the cluster. Astronomers have argued that globular clusters can produce only one generation of stars, because the radiation from first generation stars would drive the residual gas not consumed in the first star generation phase out of the cluster. However, the great mass of a cluster such as NGC 2808 may suffice to gravitationally counteract the loss of gaseous matter. Thus, a second and a third generation of stars may form. An alternative explanation for the three star generations of NGC 2808 is that it may actually be the remnant of a dwarf galaxy that collided with the Milky Way. I hope you find this very interesting I did.
M1-(also known as the crab nebula) Apparent magnitude:+8.4 Apparent size:6 arcminutes.
Have you ever seen the remains of a star in its old age? If not, take out your scope on a clear night and point it towards the constellation Taurus. Locate the 2nd- magnitude star Zeta Tauri, and from here move your telescope one degree northwest. M1, the famous crab nebula will be right in the centre of your eyepiece's field.
The nebula is all that is left of a supernova that erupted nearly one thousand years ago. Ancient Chinese records indicate that the supernova exploded on July 4, 1054. For several weeks it shone far brighter than Venus and was even visible in daylight. This spectacular event was also recorded by Anasazi Indians, in pictographs on the rock walls of canyons in Navaho and White Mesa (Arizona).
This is the second of four periodic comets discovered by Paul wild from the astronomical institute of Berne. It was first noticed on photographs taken in January 1978.comet wild 2 is noted for being a relatively ‘fresh’ comet in the inner solar system. A close encounter (0.2 AU) with Jupiter in 1974 (four years before the comets discovery) moved the comet into its current orbit. Prior to 1974,the comet is calculated to have come no closer than 5 AU,with a period of nearly 40 years. In January 2004,Nasa’s stardust probe flew past the comet.
Regulus Double star And Gamma leonis
Regulus is a double star (mg 1.4 & 7.7) with it’s companion being 177’’ away and is visible, even in binoculars. Gamma Leonis or Algeiba is a double star (mg 2.2 & 3.5), described by Burnham as one of the finest double stars in the sky. They are both yellow in color but the pair is very close and difficult for low power telescopes to resolve.
Ngc 3242 pn in hydra (ghost of Jupiter):Magnitude: 8.60 Size: 25"
The ghost of Jupiter is considered to be one of the finest pne for any sized scope. This object was discovered by William Herschel in 1785.
In a small telescope it appears as small, oval disk that bears a close resemblance to Jupiter hence the name. Like most bright pne it appears pale blue or green to the eyes of most observers.
For those with access to larger-aperture telescopes, ngc3242 has an abundance of delightful detail in store.
Ngc 1532 gx in Eridanus Apparent magnitude-10.7 Apparent size 12’.6 x 3’.3
NGC 1532 is an edge-on barred spiral galaxy in the constellation Eridanus.
NGC 1532 is one of many edge-on spiral galaxies that possesses a box-shaped bulge. This is an indication that the bulge is actually a bar. Such bars are easy to detect in face-on galaxies, where the structures can be identified visually. In inclined galaxies such as this one, however, careful analyses are needed to distinguish between bulges and bar structures.
NGC 1532 may possess several dwarf companion galaxies. The galaxy is clearly interacting with one of these galaxies, the amorphous dwarf galaxy NGC 1531. The tidal forces from this interaction have created unusual plumes above the disk of NGC 1532.
Ngc 1888 and 1889 gx in lepus (challenge for big scopes) Vmag-12.1 and 13.1 respectively.
I couldn’t find any info on these galaxies. These ought to be a good challenge for everyone.
Ngc 3201 Glob in Vela Apparent magnitude-6.8 Size (arc min): 18.2
I couldn’t find any info on this glob does anyone have any?
Hope you have fun doing the challenge
regards orestis
ps-i'll post some charts on most of the objects later.
Nice targets Orestis, something for everyone! NGC 3201 is a nice bright glob, but has low central condensation. Looks good even in a small scope. The galaxies NGC 1888 & 1889 are in Lepus, not Lupus, but good targets at the moment anyway. 1888 is a very elongated galaxy - 1889 is a much smaller elliptical that virtually sits on 1888 as we see it.
It's radial velocity and galactic position show that NGC 3201 is orbiting the Galactic centre in a unique retrograde direction to that of the rotation of the Milky Way Galaxy. This has resulted in a belief that it is a captured globular though its similar age to other standard Milky Way halo globulars tends to refute this thinking. The much younger globulars like Pal 12 etc which indeed may be captures have lower abundances than most halo globulars.
Summarised from The Astronomical Journal 1998 August: Elemental Abundances In Giants In NGC 3201, A Globular Cluster With A Retrograde Orbit - Guillermo Gonzalez & George Wallerstein.
Comet 81p/wild 2 - A very interesting object indeed... The star dust mission actually captured particles from the comet and returned them to earth! The probe now sits in the smithsonian!
My notes of NGC 3242 from December 29 2009 using the 12" dob.
NGC 3242 Ghost of Jupiter
PNe, Hydra, Size = 45x36", Nag V = 7.8
Another favourite. Intensely blue. The eye shape and surrounding halo + the central star was clear at 283x. Increasing power to 566x provided a fantastic view, the rim of the eye was beautifully sharp, the corners of the 'eye' were distinctly thicker than the rim, (like the stylised graphical impressions you usually find of the human eye). The central star was nice and pinpoint. The outer halo was well defined and uneven in surface brightness, particulary at each "end", where the brightness seemed to drop off.
My notes of NGC 3242 from December 29 2009 using the 12" dob.
NGC 3242 Ghost of Jupiter
PNe, Hydra, Size = 45x36", Nag V = 7.8
Another favourite. Intensely blue. The eye shape and surrounding halo + the central star was clear at 283x. Increasing power to 566x provided a fantastic view, the rim of the eye was beautifully sharp, the corners of the 'eye' were distinctly thicker than the rim, (like the stylised graphical impressions you usually find of the human eye). The central star was nice and pinpoint. The outer halo was well defined and uneven in surface brightness, particulary at each "end", where the brightness seemed to drop off.
Very nice description Sab,
Can't wait to observe this pne haven't seen it yet.
Orestis
Ps-Oh and here are the charts.Sorry don't know what degree field it is.
Can't wait to observe this pne haven't seen it yet.
Orestis
Ps-Oh and here are the charts.Sorry don't know what degree field it is.
Thanks mate. I think you'll like NGC 3242, it is one of the most richly coloured DSOs out there, not to mention its bright, brighter than M57 and as far as PNe's go, a real winner.
Thanks Orestis for posting this selection of varied objects.
Just as an aide on the NGC 1888 (also Arp 123) & NGC 1889 pair of eg, here are some notes that may be of assistance as a guide. NGC 1888 is in the Arp catalogue and (photographically) has a distinctly warped disc probably as a result of interaction with NGC 1889 that has a very similar R.V and therefore presumably a very likely similar distance. It is probably that peculiarity that brought to to Halton Arp's attention.
25cm x86 in 1996 suburban location (NGC 1888 only):
"Mag 19 Size 2.9'. Very LSB patch appearing just slightly off round in PA 30??. Rising only very slightly to centre. A.V very necessary. Lots of scattered mag 11 *s in the field. "L" shaped asterism to the S + another mag 11 * very slightly to centre."
NGC 1889 & 1888 are in a close pair. NGC 1888 is the major partner of this pair. It is a nice elongated edge on type spiral, maybe 2' x 10" in PA 150. It shows a pretty easily seen brightening to the axis near centre but no readily apparent core or nucleus. Just N of the nucleus -- just adjacent and appended is NGC 1889 which at first glance could be mistaken for a faint star, but it does have a very small, perhaps 15" diameter halo that rises sharply to the centre where there is a faint *ar nucleus.
And most importantly (Da-da-da daaaa) , well done to Mr PGC (§AB) on his 1000th post (immediately above this post). Excellent contribution !!
Hi Orestis & PGC,
And most importantly (Da-da-da daaaa) , well done to Mr PGC (§AB) on his 1000th post (immediately above this post). Excellent contribution !!
Well I've got the Ghost of Jupiter (NGC 3242) Hoping for a clear night on Saturday as I am heading up to dark skies at Heathcot for a night of observing.
Hope to get a few more there!
Well, I made a start on the list tonight with the 4.5" & 21mm EP, battling cloud that was making & breaking across the sky. Only time I had good transparency was briefly in the Vela/Carina area and the two globs came up really well. NGC 2808 was wonderful - bright & centrally condensed. NGC 3201 was larger but much duller, and in averted imagination I thought I could make out two faint fuzzy lines of stars going into it, making a "V".
Regulus double was fine, big separation, but didn't even bother going for Algieba at 4.6"! Lovely yellow 'star' anyway! M1 never came out of cloud. PN NGC 3242 was a shock - such a lovely small bright thing! Only had the briefest of views between clouds & will return to it with higher powers. Must have seen it before, but honestly can't remember it.
Galaxy NGC 1532 never really came out properly from the murk, but I did get tantalising glimpses of it. Long time since I've seen it, and definitely one for a better night. Don't have a realistic shot at galaxy NGC 1888 at mag 12.8, but found the field & position anyway. Just for a lark I might give it a go if I get a stunner of a night.
Comet 81P never really came out of the murk either, and despite spending more time on it than the rest put together, I only got a couple of the vaguest hints of something there. At times I couldn't see the mag 10 star it was near. I was battling to see nearby 74 Virginis naked eye, at mag 4.65!
Here are my notes on the objects in the challenge. Haven't got to the double in Leo or the comet yet.
It was very enjoyable to tour through the list - thanks for putting it together Orestis.
Telescope 400mm f4.9 tri-dob reflector
Eyepieces 28mm UWAN, 17,13,9 mm Naglers, Paracorr
Guiding: Night Sky Observer’s Guide (NSOG)
Seeing and transparency excellent
Messier 1 SNR Crab Nebula 175x Bright nebula, seems about 7’x5’, appears roughly oval shaped on first glance. Closer inspection shows the eastern and southern edges look more ragged with brighter areas to the south and east encompassing a darker patch of nebula. The nebula looks slightly pointed toward the north and there is a notch of darkness at the northwestern edge. The nebula seems to bulge a bit to the west. There is a N-S bar of brightness UHC filter in the middle of the nebula. The whole thing brightens under UHC filter at 175x and the central bar shaped area does so in particular. The dark patch to the southeast becomes more distinct. The nebula looks more mottled with UHC. Much fainter with OIII, rounder in shape and more mottled still throughout.
NGC 1532/1531 interacting galaxies in Eridanus 175x 1531 to the West of 1532 which is an edge on spiral oriented N-S. 1532 seems about 8’-10’ long and about 2’ wide with bright nucleus apparent. 1531 seems to be heading into the larger galaxy a little to north of the nucleus. 1532 has some bright patches along the disc especially towards the south. I have an impression of dust lanes again more to the south of the nucleus. 1531 is much smaller and rounder and looks about 1’ away from 1532. I have the impression of some haze between the two galaxies. 250x shows much more structure in 1532, with quite a bright patch halfway between the nucleus and the southern edge of the disc and other scattered bright patches along the northern part of the disc. Dark dust lanes are visible on the disc.1531 is quite bright and somewhat grainy looking. 350x shows even more detail and texture
NGC 1888/1889 Arp 123interacting galaxies in Lepus 250x A pair of small faint galaxies 1888 an edge on spiral oriented roughly NW-SE and very close to the SE is 1889. Some central brightness in 1888 but not what I’d call a distinct nucleus. 1888 looks a little fatter and distorted at the SE end.
NGC 2808 GC in Vela 175x Quite bright central core and a very concentrated cluster with a number of strands distracted from the main body. Some resolvable stars but mostly a grainy haze. Strand to the west associated with a bright star, another strand to the southwest, and a third wide strand to the north which spreads out more as it gets 5-6’ from the cluster itself. Another strand to the northeast. The cluster itself looks a little squashed, longer in SE-NW axis. I can’t tell whether it is actually squashed, or just looks that way because of the strands of stars and haze. The brightness fades evenly from the core to the edge of the cluster.
NGC 3201 GC in Vela 135x A very spread out cluster with no obvious core. Many resolvable stars scattered right across the GC with some strands of haze and scattered stars. A wonderful contrast to 2808.
NGC3242 PN in Hydra the “Ghost of Jupiter” 175x Very bright PN I have a very distinct impression of 2 shells. Central shell is bright and firm-edged and central star is apparent. The inner shell covers about 2/3 of the dia. of the nebula. The SE side of inner shell seems a little brighter than the rest of this shell. UHC filter diminishes outer shell – it is still apparent but less distinct, the firm edges of the inner core soften and it appears to meld into the outer shell. The brightness of the SE edge is enhanced and there appears to be a dark curve on the NW edge. 250x some detail lost as wind is increasing and seeing deteriorates.
Well I got out again tonight, under great skies! Just using the 4.5" reflector & 21mm EP (47x). The toughies - no way I'm going to split Algieba, but at least it looked oblong when I zoomed up to 112x. Seeing was pretty woeful as usual.
BUT... I spent a lot of time on NGC 1888/9. Field is easy to pick with a couple of distinctive lines of stars. Position is about halfway between the dim fourth star of a row of four, and a brighter star about 9' away. Took me ages, especially as I was losing dark adaptation every time I checked charts etc. But I did see something! And while very, very faint it wasn't weak, and in the end with good adaptation I could hold it quite well, jiggling the scope around. It was a very small roundish patch - I would reckon less than 1' diam. Maybe the core of 1888 or reinforced 1889. Not the slightest sign of any extension of the edge-on, whatever I did. Rapt, that's really dim!
For the rest, saw the two globs - with better conditions, much brighter & larger extent, but not much to add to what I posted before. Lovely targets! Galaxy NGC 1532, instead of a fleeting ghost, was quite strong. I could see the thin core, bright for about 4' length, and with averted vision the galaxy appeared to extend for about 10'. M1 was quite nice, a strong grey oval. Even though it was pretty low, it had to be one of my best views ever - there even appeared to be some slight mottling at times but it was hard to pin down. Comet 81P was quite easy to pick, but never more than a faint flickering ghost and no sign of the tail. Might have been better if it was in the clear (and higher!), but it was quite close to a small star. Pleased nonetheless because a mag 10 comet like that is no easy target in a small scope! NGC 3242 was very bright. Tried it at 112x and while it stayed nice and bright, I couldn't see any detail.
So assuming TYC833-134-1 is Regulus' companion, that's pretty much it!
Thanks Rob. I am always amazed at what you achieve with your 4 1/2 scope. You demonstrate the power of careful observation. There's no way I would have thought you'd get to see NGC1888/9. I dips me lid to ya.
Thanks Rob. I am always amazed at what you achieve with your 4 1/2 scope. You demonstrate the power of careful observation. There's no way I would have thought you'd get to see NGC1888/9. I dips me lid to ya.
Thanks Patrick! Re 1888/9, a real buzz getting something in terms of the challenge but not a meaningful observation in my book (other than great practice), and dim galaxies like these I'm more than happy to leave to the "big boys"! And I'm glad you realise it's all down to the quality brand of the scope pgc!
Any other reports, anyone? How did you go on Saturday Malcolm?
Sorry Rob, Saturday was a washout, up to midday the skies were lovely, forecast looked OK so I headed off. As I drove, more and more cl;ouds formed, socked in by time I got there.
Bit sad but there you go!
Haven't had the chance to do the full Challenge yet, as I wanted to do more in Puppis. Now we have all that tropical rubbish cloud and rain. Grumble grizzle.
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NGC 3201 is a nice bright glob, but has low central condensation. Looks good even in a small scope. The galaxies NGC 1888 & 1889 are in Lepus, not Lupus, but good targets at the moment anyway. 1888 is a very elongated galaxy - 1889 is a much smaller elliptical that virtually sits on 1888 as we see it.
Seeing was pretty woeful as usual. 
