A Wink of Color

NGC 6826

NGC 6826
Sketch and Details by Jeremy Perez

Observation Notes:

NGC 6826, also known as the Blinking Planetary, was pleasantly bright when I tracked it down at low power. It exhaled a blue-green color at all levels of magnification. At 240X, it displayed a shelled structure with an outer shell that appeared circular while the inner shell was elongated at a PA of about 135 degrees. This inner shell was bright enough to make the central star appear to almost blend into it. I did not notice a blinking effect on the nebula, but detail was lost to direct vision. I estimated its diameter to be about 40 arc seconds. This estimate turned out to be fairly poor, as the actual diameter is 27 x 24 arc minutes. If you’re in the area enjoying M27 and M57, reward yourself a look at this beautiful planetary nebula too.

Object Information:

NGC 6826 was discovered by F.W. Herschel in 1793. High resolution photographs reveal an elliptical nebula with an eye-like appearance. Between the inner and outer shells, along the long axis, two red “FLIERS” can be seen. The cause of these structures is yet to be determined, but Hubble telescope images seem to indicate that these FLIERS are stationary while ejected stellar material flows past them–sculpting them in the process. NGC 6826 is also catalogued as PK83+12.1, H IV-73, h 2050, GC 4514.

Subject NGC 6826
Classification Planetary Nebula (3a(2))
Position Cygnus [RA: 19:44:48.17 / Dec: +50:31:30.4]*
Size* 27″ x 24″
Brightness* 8.8 vMag / 9.8 bMag (Central Star 10.4 mag.)
Date/Time August 13, 2007 – 01:30 AM MST (August 13, 2007 – 08:30 UT)
Observing Loc. Flagstaff, AZ – Home
Instrument Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag. 10 mm Sirius Plössl + 2X Barlow (240X)
Conditions Mostly clear, calm
Seeing 4/10 Pickering
Transparency ~ Mag 5.8 NELM
*References NGC/IC Project, Bruce Balick, University of Washington

Planet Number Six

Saturn

Saturn
Sketch and Details by Frank McCabe

This was my first attempt at sketching the planet Saturn while using white Conte’ crayons on black paper. Over a period of 3 hours I made 4 drawings of Saturn. The first 3 made during the first two hours looked terrible but the third one, although rough and grainy looking, came out recognizable as a ringed planet. I have nothing but the highest respect for those sketchers that regularly and beautifully draw this planet.
I could clearly see the dark planet shadow on the A and B rings. I could not hold the C ring constantly visible and so I did not include it in the drawing. The Cassini division was clearly visible but not the Encke division. Contrast between the brighter equatorial zone and the southern equatorial belt above it were easily seen. Four of Saturn’s moons were easily seen when the high thin clouds moved on. Clockwise starting above the planet in the drawing is Titan (mag.8.8), then Tethys (mag.10.7), next Rhea (mag.10.2) and finally Dione (mag.10.8). Mimas and Enceladus were in the field of view but hidden by the planets glare.
Saturn and its moon make wonderful targets for a clear night at the eyepiece of a telescope. Sketching the view just simply adds to the enjoyment.

Sketching:

For this sketch I used: black Strathmore 400 Artagain paper, 8”x 11”, white and black Conte’pastel crayons, an eraser shield, and a blending stump. Brightness was slightly decreased (-5) and contrast increased (+3) after scanning using Microsoft Office Picture Manager.

Telescope: 10 inch f/5.7 Dobsonian and 6mm eyepiece 241x
Date: 5-5-2008 4:00 – 5:00 UT
Temperature: 13°C (56°F)
high clouds, calm
Seeing: Pickering 6.5

Pen and Ink Petavius

Petavius Crater

Petavius Crater
Sketch by Michal Repik

Michal Repik is a seventeen year old amateur astronomer from the Czech Republic. He has been sketching his astronomical observations for the last three years.

Information about the observation:
Date: May 5, 2008
Time (UT): 21:10
Telescope: Maksutov
Aperture: 127 mm
Focal Length: 1500 mm
Magnification: 200x
Observation place: Prague
Lunar colongitudo: 312.6°
Seeing: 2/5 (ant.)

A Splinter in Virgo

NGC 5170

NGC 5170
Sketch and Details by Kiminori Ikebe

NGC 5170 Vir galaxy
2000.04.09 01:35
32cm at 150x

A good contrast with the face-one galaxy NGC 5247 located 1.7 degrees to the east. Not very bright but a fine sight with a very long and narrow shape. No bulging at the center. A long and narrow central condensation with a gradual fading towards the ends.

The Sun, Pencils or Camera?

H-Alpha Sun

H-Alpha Sun
Sketch and Details by Les Cowley
Comparison Photos by Pete Lawrence

The Sun is an ever-changing target. In H-alpha light, prominences light and
dim, shift and change literally by the minute. Fascinating to watch and
sketch but just how accurate are drawings grabbed in a few minutes during
variable seeing and under a black hood?

May 7th was an opportunity to find out when Cloudy Nights held an
“International Day of the Sun”. Expert UK photographers Peter Lawrence and
Nick Howes suggested imaging or sketching a prominence every 30 minutes on
the hour and half hour!

The day dawned clear and after breakfast the selected prominence was viewed.
It was the ugliest assortment of filaments, clouds and loops that you could
imagine with parts changing and dancing about even as you watched. The
‘scope was a Coronado Solarmax60 mounted on a manual altazimuth. Seeing
started fairly good so I used an 8mm Radian, I need eyeglasses to sketch and
the Radian gives enough eye relief. The drawings were on A4 black Canford
paper filling half the sheet per sketch with Derwent Watercolour pencils
used sharp and dry.

Serious observing started about 8 minutes before each time mark with the
main proportions starting to be put in 5 minutes before the mark. Then finer
and finer details were quickly added, not in any order just wherever good
seeing happened to show them. This quickly brought the time to the mark and
then the whole view was assessed for accuracy. It was changing so fast!
Finally 3-5 minutes after the mark were spent getting the relative
intensities right and generally tidying up.

By 09:45 there were frequent periods of superlative seeing and I changed to
a 5mm Radian and clutched the dark hood around close to shield the daylight.
For long periods (but never, ever during the allocated 10 minute slots!) the
visible structures were exquisitely resolved into delicate stacked filaments
with even those sometimes doubling and breaking into knots – you would need
an hour or hours to capture all that! After 10:30 the seeing deteriorated
and that combined with not a little fatigue ended the sketching run.

Pete Lawrence was imaging some 150 miles to the south with about the same
seeing conditions. He used a Solarscope SF-70, a Rolls-Royce of H-alpha
filters. His images for the same times are on a reduced scale at the base
but you need to see the originals (http://www.digitalsky.org.uk/ and Cloudy
Nights) to really appreciate their superlative quality.

So can sketching such ephemeral objects ever be accurate? I’m still
deciding. There is maybe a tremendous amount to be leaned from a careful
comparison of sketch fragments with simultaneous photographs about how the
eye-brain interprets fine details and tends to join others into spurious
larger structures. If some of that can be understood then hopefully it might
improve the sketching accuracy.

Les Cowley, England

Down a Jagged Path

Meteor

The Meteor of July 27, 1894
Illustration by Chauncey M. St. John

THE METEOR OF JULY 27, 1894, 7h 30m P. S. T.
By EDWARD S. HOLDEN.

A great number of observations of this splendid meteor were received at the LICK Observatory, either directly, or through the kind offices of Hon. A. S. TOWNE, Hon. C. F. CROCKER, Hon. R. THOMPSON and others. Some of the best were not available till the middle of October. Very complete observations of the meteor’s position and appearance were made at Mount Hamilton by seven observers. Professor AITKEN of the University of the Pacific sent the only complete observation received here, viz., the altitude and azimuth of the meteor when it exploded, and the same co-ordinates of the point where it disappeared. Many good determinations of the point of explosion were received, the best being those of Professor FRIEND (Carson), Mr. CARLETON and Mr. BURCKHALTER (CHABOT Observatory), Mr. GEORGE BRAY (Santa Clara), Mr. W. B. JOHNSON and Mr. STONEROAD (Merced), Mr. HERROLD and Mr. HERRING (San José). Drawings of the brilliant cloud left by the explosion were received from Professor SCHAEBERLE (Mount Hamilton), Mr. JOHNSON (Merced), Mr. STEWART (Visalia); and excellent accounts of this cloud from Dr. O’BRIEN (Merced) and others. A beautiful and artistic water-color drawing of the phenomenon has been presented to the Observatory by Mr. CHAUNCEY M. ST. JOHN, which represents the general appearance in a most satisfactory way. The determinations of the place where the meteor disappeared were not so satisfactory, the reasons being, no doubt, that everyone’s attention was riveted on the cloud left by the explosion, and because the meteor divided into two portions near the end of its course.

When the last reports were received it was possible to fix with considerable precision the point where the meteor exploded. This point is in the zenith of a place about half a mile south and about half a mile west of the N. E. corner of T. II E., R. 8 S., M. D. B. and M. The explosion took place when the meteor was a trifle over 28 miles above the Earth’s surface.

It is not so easy to fix the place where the meteor fell. Bakersfield, Hollister, Los Gatos, Madera. Merced, Minturn (two observers), Mount Hamilton ( E. S. H.), San José (two observers), report that the meteor moved north as it fell.

College Park and Mount Hamilton (R. H. T. and A. F. P.) report that it moved south in falling.

Borden, Carson, Crow’s Landing, Fresno, Livermore, Los Baños, Oakland (CHABOT Observatory), Riverside, San Andreas, Santa Clara, Vallejo, Visalia, report. th.e direction of its’fall as substantially vertical; and, in default of more accurate data, I have assumed this to represent the facts.

The meteor disappeared before it reached the Earth. The fragments produced by the explosion were probably volatilized by the time they reached a height of some 6 miles above the Earth’s surface. It is hardly likely that any large fragments reached the Earth. If so, they should be sought for within a circle of some 12 miles in diameter, whose centre is the point previously described. If the observations of the point where the meteor disappeared had been more accurate, the place of the fall would have been better determined.

The meteor was seen by several observers long before it exploded—probably when its height was over 70 miles. The position of the radiant-point is R. A. 16h 0m, Declination +34°.5.

With these data I have calculated the orbit of the meteor. As the data are (in general) not very precise the elements of the orbit are but approximate. The orbit is assumed to be a parabola. The elements are:

Pi = 130°,
Omega = 125°,
i = 20°,
q = 1.016.

The meteor was then a little nearer the Sun than the Earth it was near perihelion, and moving in an orbit inclined some 20° to the ecliptic.

The Regents of the University have authorized the printing of a pamphlet on this subject, which will (in due time) be sent to our correspondents. This pamphlet will also contain the observations of the August meteors of 1894 made by Professor SCHAEBERLE at Monte Diablo, and by Messrs. COLTON, PERRINE and POOLE, at Mount Hamilton.

From The Publications of the Astronomical Society of the Pacific, Volume VI, 1894, pages 268-270 at Google Books

Hydra’s Fleeting Visitor

C/2007 W1 (Boattini)

C/2007 W1 (Boattini)
Sketch and details by Eric Graff

Here is my sketch of comet C/2007 W1 (Boattini) on it leisurely coarse through the starfields of western Hydra. The coma has an overall diameter of at least 12′ and an apparent visual magnitude in the 7.5-8.0 range. The soft, diffuse glow brightens gradually to the center, with occasional glimpses of a smaller, more intense concentration at the core. The whole seems to have a slight aqua tint, but that impression of color tended to be fleeting at best.

May 4, 2008 Solar Collage

Sun

H-Alpha Sun
Sketch and Details by Erika Rix

PCW Memorial Observatory, Zanesville, Ohio, USA, Lat: 40.01 / Long: -81.56

Erika Rix

Temp: 54.0°F / 12.2 °C
Winds: 5.8 mph NW, clear turning to partly cloudy
Humidity: 53%
Seeing: very poor 2/6
Transparency: 4/6

Equipment:
Internally double stacked Maxscope 60mm, LXD75, 40mm ProOptic Plossl, 21-7mm Zhumell, ETX70AT, 8mm TV Plossl

Sketch Media:
H-alpha – Black Strathmore Artagain paper, white Conte’ and Prang pencils, white vinyl eraser.

White light pores created in Photoshop.

New active region in the ESE quadrant was visible with two crescent shaped plage facing each other during the h-alpha observing session. In white light, seeing was very poor making it invisible at first glance. Eventually my eyes were able to see two dark specks in the AR, appearing to be only umbrae, with the more easterly one slightly darker and thicker.

No faculae were noted in white light.

Of the prominence activity in h-alpha, the long line of southern prominences had filament reaching out over the disk on the far western edge. The large eastern edged prom in this line was leaning at a crook to the east (right) in my FOV. It was also the faintest of the four more prominent prominences around the Sun’s limb.