Author: Jeremy Perez

The Fetus in Cygnus

NGC 7008

NGC 7008
Sketch and Details by Ferenc Lovró

NGC 7008 (planetary nebula)
Date/time: 2008.09.02 23:00 UT
Equipment: 12″ f/5 Newtonian
FOV: 12′ Mag: 250x
Seeing: 6/10 Transparency: 4/5

A very large planetary nebula in the Cygnus constellation, also known as the Fetus nebula. Its naming perfectly suits its look, which is very conspicuous. It’s an asymmetrical shell with widely varying brightness and an enormously shiny area to the NE. The central star is 13.2 magnitude, easily detectable because it is surrounded by dark areas. To the east, you may notice another star of the similar colour and luminosity. I cannot see any hint of colour throughout the planetary. It’s a nice object even at low powers of around 100x thanks to its relatively high surface brightness, therefore it may be a reachable target for small telescopes too. I’ve tried using my UHC filter, but the results were worse than without it.

Solar Awakening

H-Alpha Sun

Solar Prominences
Sketch and Details by Les Cowley

After weeks of inactivity the sun stirred at the end of September ’08. The 28th saw a huge but faint prominence on the Southeast limb and the next morning revealed two large and bright prominences almost diametrically opposite each other on the SE and Northern limbs. They are pictured here as viewed from England through a Coronado 60mm H-Alpha single-stacked telescope at 50 and 80X. The sketches were made at the eyepiece with Derwent Studio, Watercolour (dry) and Drawing pencils on black Canford paper. A black hood blocked out extraneous light. Each had to be finished within 10 minutes because the prominences, particularly the southern one, were evolving quickly.

Eclipse’s Delicate Blossom

2008 Eclipse

Total Solar Eclipse – August 2, 2008
Sketch by Serge Vieillard

Serge Vieillard made this sketch of the total solar eclipse of 2008 from the Gobi Desert in China. In the minutes leading up to totality, clouds threatened to hide the event from his eyes. He raced 1000 meters from his initial location to find a clear spot, only to have the clouds drift there as well. In the final moments however, the clouds broke and he was able to spend an ecstatic 2 minutes drawing the view through his Kowa TSN-2 77 mm spotting scope at 20X. As the seconds passed and his eyes adapted, he crafted the increasingly complex, asymmetrical contours of the Solar corona and noted a bright star in Cancer. During the final few seconds of totality, the pink bloom of a prominence emerged and topped off an exciting and memorable observation.

Holmes’ Mega Coma

Comet 17P/Holmes

Comet 17P/Holmes
Sketch and details by Martin Mc Kenna

Nov 3/4 18.20 – 20.00 local time.

Tonight 17P/ Holmes was a spectacular object to those lucky enough to have dark skies. This was a night of revelation for me. In the 8.5″ F/7 reflector I measured the brighter inner coma at 15′ in dia. It was a bright lemon colour with beautiful segmented ring around the perimeter like a horse shoe with bright enhancements and dark obscurations. The N side described a beautiful curve with the S section soft and broken in profile. At centre was a very faint and soft false nucleus which looks more like a well defined smudge rather than stellar in the 32mm eyepiece. The dust fan was still bright and elongated to the south where it merged into a vague void of complexity where all the finer action was taking place. Surrounding the FN was 3 dark wedge-shaped holes or pits in the region between the FN and inner coma. By sweeping the telescope back and forth I could see the green transparent outer coma for 30′ either side of the inner coma. Since this central region was 15′ across I got a total diameter for the outer coma at 75′ or 2.5 times the apparent size of the Moon. The other coma has a very sharp edge with obvious cut off point where the coma ended and the background sky began. It was a disk-like shape very much like a CD. This effect was enhanced by the stunning dark ‘lip’ which surrounded the inner coma like a jet black scarf much like what is now being picked up on CCD images. This dark collar was very well defined and by letting the comet drift across the field I could see its passage with ease as it first entered then drifted in transit across the 1 degree FOV. The shape of this feature reminded me of an ‘Arcus’ or ‘Shelf Cloud’ which marks the gust front of a thunderstorm. I observed two long Ion tails, the first to the S and the second to the SE with the first being 1 degree in length. A nice fan of multiple fine streamers spread across the void between these two long linear features where the inner and outer coma meet.

My 10x50mm binoculars have a FOV of 5 degrees. Using these I was astounded to see the coma taking up much of the field which I estimated at 3 degrees in dia or 6 full Moon diameters!!. I couldn’t believe what I was seeing and was reserving severe doubts about the whole thing until I saw it easily again with well defined edge which flirted with the eastern most stars within the large open cluster between Alpha and Delta Persei. The entire sharp dark green outer coma looked like a smaller version of the Gegenschein during the times when it can be seen as an oval glow. Further more the ‘disk’ was not a perfect circle. The southern end looked ‘missing’ as if a wedge shaped section had been cut from the coma with scissors. I recently recall one observer describing this outer coma as shaped like a Jelly Fish and this was more or less what I could see also. Extending from the void in the southern section was a long linear ray of light approx 2 degree long. I do not know if this was a long ion tail or just an enhancement along the inner edge of the coma. Confused by the whole thing I decided to delay this observation until I could confirm it myself.

Tonight (Nov 4/5) the sky was stunning and very dark. In the 10x50s I could see the same size of coma and shape as observed on the night before. However even more astonishing was the view with the naked eye on this grand night. Using my finger tips held at arm’s length I could see the entire coma extending for approx 5 degrees in dia (10 Moon diameters) with the naked eye!!!.

I now believe that any future visual mag estimates and D.C estimates will be almost impossible with any degree of accuracy but for what it is worth I will stick to my last estimate of +2.5 at D.C:7

The Falls of Camelopardalis

Kemble’s Cascade

Kemble’s Cascade
Sketch and Details by Kiminori Ikebe

Kemble’s Cascade Cam
a line of stars

NGC 1502 Cam
open cluster

1999.12.31 01:02
10X42 Binoculars

A fine line of stars. Five to 10th magnitude stars are lined up in a straight line over a distance of about 2.5°. As it is large, 10×42 binoculars are most suitable. It is visible in a 3cm finderscope but looks partly nebulous. It stretches from the southeast to the northwest. The southeastern end of this stretch splits into two. Maybe this is where the base of the water falls is. Near the eastern end there is a bright star. With a careful look the star looks smudged at the edge. It is the open cluster NGC 1502. Near the middle of the line of the stars is the brightest star (5th magnitude); other stars are mainly of 8th magnitude. More than 20 stars are seen as a whole.

More of the Southern Highlands

Southern Highlands

Lunar Southern Highlands
Sketch and Details by Frank McCabe

I have always found the southern highlands an interesting region of the moon to examine along the terminator. At the times of low sun the craters here take on more unique and individual identities than at higher illumination. On this observing and sketching night, I managed to examine and sketch five notable craters. From south to north along the terminator are Boguslawsky (98km.), crater Boussingault E ( 98km.) and Boussingault B (54km.). All over the southern highlands are numerous, ancient, worn, soft looking craters between 10 and 90 kilometers in diameter. Some of the craters in this region pre-date the formation of the major lunar basins. These craters look soft and dusty with smooth terraces and regolith slumping to the crater floors. Lunar geologist Donald Wilhelms speculated that the appearance of the craters here is caused mostly by fluidized ejecta and debris tumbling down the crater walls to the floor. He also believes that the craters in the region of the sketch are sitting on an ancient 650 kilometer basin that is all but destroyed save for pieces of rim here and there. The two craters further west from the terminator from south to north are Manzinus (98 km.) and Mutus (78 km.). Craters B and A, both about 16 km. in size, can be seen on the floor of Mutus.
As a target the moon proved to be a very enjoyable subject on this evening of observation and sketching.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper 10”x 8.5”, white and black Conte’ pastel pencils and a blending stump. After scanning, Brightness was decreased (-2) and contrast increased (+2) using Microsoft Office Picture Manager.

Telescope: 10 inch f/ 5.7 Dobsonian and 9 mm eyepiece 161x
Date: 9-18-2008, 4:05 – 5:30 UT
Temperature: 15° C (60° F)
clear, calm
Seeing: Antoniadi III
Colongitude 129.5 °
Lunation 18.4 days
Illumination 90 %

Frank McCabe

A Swarm within a Swarm

NGC 1502

NGC 1502 and Struve 485
Sketch and Details by Eric Graff

NGC 1502 and STF 485
Open Cluster and Multiple Star in Camelopardalis
Parks Astrolight EQ6 • 6″ f/6 Newtonian Reflector
7.5mm Parks Gold Series Plössl • 120x
Field of View 26′
31 December 2007 • 03:30-04:30 UT

Dangling off the southern end of Kemble’s Cascade, one the sky’s better-known asterisms, you will find the open cluster catalogued as NGC 1502. Easily visible, even at low magnifications, as an unmistakable glittering mass of stars, the cluster is dominated by a brilliant pair of 7th-magnitude snow-white suns separated by 18″ of arc in position angle 305°. These two are the principal members of the multiple star STF 485 (ADS 2984; CCDM 04078+6220).

Increasing the magnification brings better definition and resolution to NGC 1502. A 7.5mm G.S-5 Plössl yielding 120x provided the most pleasing view in my scope, and this was used in the sketch presented here. All of the cluster stars appear to be pure white (or nearly so). The brightest stars in the cluster are concentrated into a narrow east-west band of stars spanning the cluster’s 8′ diameter. Most of these are members of the STF 485 system.

The Catalogue of Components of Double and Multiple Stars (CCDM) lists 16 members for STF 485 with magnitudes ranging from 7 to 14; these are designated (A-P) as indicated on the inset. Components C, E, F, G and M are very challenging due to faintness (mags 11.9-14.1) and proximity to A and B; the remaining members are quite easy by comparison. Component B is also a variable star, designated SZ Camelopardalis. It is a Beta Lyrae-type eclipsing variable with a period of just under 2.7 days and a magnitude range from 7.00 to 7.29. While component A might seem like a convenient comparison star for making magnitude estimates of SZ, it is suspected of being variable as well, with an observed amplitude of about 0.1 magnitude. Components H, I and J are also catalogued separately as STF 484 (ADS 2982); components K and L are catalogued separately as Holmes 3 (ADS 2989).

William Herschel discovered NGC 1502 on November 3, 1787 with his 18.7-inch reflector. It is sometimes called the Golden Harp Cluster; it contains 63 member stars and lies 2,650 light years away in the direction of Camelopardalis. Its age is estimated at 5 million years.