Star – Page 16 – Astronomy Sketch of the Day

Three’s Company

12 Lyncis – Triple Star
By Wade V. Corbei

This is an interesting triple star in the constellation Lynx, and required a good bit of magnification to resolve into 3 seperate stars. In the 27mm, it just looked like an elongated star, and in the 15mm, I could just discern that there was more than one star. When I barlowed the 15mm, I could easily see that this was a multiple star system, but I could not split the two eastern stars.

I plopped in my 6mm and barlowed that and there it was…a nice split of all 3 stars in the same FOV. Wonderful!

I don’t really know what the primary star would be with this trio as all 3 appear to be of the same (or close to the same) magnitude. It does appear as if the two stars on the eastern end are brighter and appear as white with just a hint of a blueish tint. The third star that is well seperated and to the west appeared as having an orange or burnt-brown coloration.

A nice triple star system that can be a challenge, but once found makes for an interesting and neat sight in the ol’ EP.

Wolf-Rayet in Vela

Gamma Velorum
By Rogerio Eirado

The brilliant Gamma Velorum system is composed of at least 6 stars. The primary star of this system is actually a spectroscopic binary that has been dubbed the Spectral Gem of the Southern Skies because its exotic spectrum is dominated by bright emission lines rather than dark absorption lines. It is composed of an O9 blue giant and a massive Wolf-Rayet star that are separated by 1 AU and orbit with a period of 78.5 days. The Wolf-Rayet star probably started its life at around 40 solar masses, but has blown most of that mass away and is now probably closer to 10 solar masses. Both stars in this pair have extremely powerful winds, and as these winds collide they produce X-Ray emissions. The Wolf-Rayet star is likely in the last stages of its path toward exploding as a Supernova. It’s companion will eventually follow suit. The B component seen in Rogerio’s sketch is a B-class subgiant and the C and D components (lined up above the A and B components in the sketch) are white A-class stars. The D component itself has a much fainter and challenging 13th magnitude companion separated from it by 1.8 arc seconds (the 6th star in the system).

Rogerio sketched this beautiful multiple star using pencil on white paper. The sketch was then scanned, inverted to a positive image, and digital methods were used to enhance and add observed color to the stars. His sketch gallery can be found here: A vida, o universo e tudo o mais.

Sources: Burnham’s Celestial Handbook, Jim Kaler’s ‘Regor’, Wikipedia

Eta Carinae from Haleakala

Eta Carinae Complex and NGC 3293
By Jeremy Perez

Move mouse over image to see labels. Click for larger image.

The observing highlight of an evening atop the summit of Haleakala in Maui was gazing through my binoculars at the rich starscape in the vicinity of Eta Carinae. I had not done any homework on the area beforehand, so I approached it with unexpecting eyes. The mottled depths of the surrounding Milky Way, the smattering of intensely bright foreground stars, the abundance of open clusters of all shapes, sizes and intensities, and the stunning patches of glowing nebulosity made the whole region a delicious feast for the eyes. One incredible open cluster to the northeast, nearly took my breath away, but I did not have time to even attempt a sketch of it. Instead, I chose to render the region bracketed by the Eta Carinae complex and a much more manageable cluster, NGC 3293.

Eta Carinae was a brilliant orange star that surrounded itself in a plush comfort of nebulosity. This misty region ended abruptly to the south and then emerged again to surround a trio of bright stars. The observation and sketch were done more hastily than I would have liked and I know there was more detail to be extracted from this bright nebula, but I took what I could get. The northwest side of the view was punctuated by the small, bright open cluster, NGC 3293. Four bright stars announced themselves within its glowing boundary of unresolved starlight.

This section of the sky is still beckoning me, and I know I will have to return to it again with more time to spare. Even if I only have binoculars again the next time, it will still offer more than I can possibly absorb.

The sketch was created on Strathmore sketch paper with 2H and HB pencils. Nebulosity was shaded with a blending stump loaded with graphite. Color was added to Eta Carina in Photoshop.

Object Information

Eta Carinae is one of the most massive stars in the universe and is likely greater than 100 solar masses. It is about 4 million times more luminous than the sun, but radiates 99% of this energy in the infrared. Due to its extreme mass, it is expected to go supernova within the next few hundred thousand years. In the meantime, as it rapidly sheds matter, it goes through sporadic, violent outbursts. The most recent outburst peaked in 1843 when Eta Carinae became a magnitude -1 star, second only to Sirius. This eruption generated a rapidly expanding plume of gas that now forms a fascinating dumbell shape.

Colorful Witness to Tombaugh’s Discovery

Delta Geminorum

By Wade V. Corbei

This is an interesting double star (in all actuallity a Binary star) found in the constellation Gemini (as noted by the name). The Primary star is much larger than the companion star, and appears as a yellowish-white, while the companion appears as a nice contasting purple. Delta Geminorum also holds a historic significance as well, as in 1930 Clyde Tombaugh discovered the planet Pluto 1/2° east of this star.

A unique star with an equally interesting history.

Second Take

394 ARI – Struve 394

394 ARI is a nice sight and contians a primary and secondary of almost equal size and magnitude with a primary with an obvious yellow tint and a secondary with an equally noticeable blue tint. This double stands fairly alone in the FOV at this magnification, but it is a very nice and easily observed double residing in Aries.

Dance of the Dwarfs

Krueger 60 A and B

I began observing and recording the position angle of Krueger 60 A and B also
called ADS15972 during the fall of 1978. In another 15.5 years I will have
observed these close orbiting red dwarf binary stars through one complete orbit.
This pair of stars also demonstrates an annual proper motion westward of nearly a
second of arc. Both of these stars are M class and are among the 40 nearest stars
to earth at just 13.1 light years. The current separation between the pair is 2.3”
of arc. In actual measurement the components are 9.2 AU apart which is about the
distance between the Sun and Saturn. The smaller component B is less than 10% the
mass of our sun and is famous for its irregular flare outbursts which can last for
10 minutes as the brightness doubles. The A component star is magnitude 9.8 and
the B component glows at magnitude 11.3. Both stars are in the constellation of
Cepheus about 45 minutes of arc from Delta Cephei which is famous as the prototype
for all Cepheid
variable stars.

Sketching:

Date and Time: 9-23-2007, 5:10-5:45 UT
Scope: 10” f/5.7 Dobsonian. 12mm eyepiece 121x
8”x12” white sketching paper, B, 2B graphite pencils, scanned and inverted, star
brightness adjustments using Paint
Averted vision was a very useful aid in this sketch.
Seeing: Pickering 8/10
Transparency: above average 4/5
Nelm: 4.8

Frank McCabe

Albireo under a blazing full Moon

I’ve never tried sketching doubles before. But the sunset was so pure that I wanted
to enjoy the night outdoors. Sketching Albireo seemed a nice plan under a moonlit
sky. While the full moon was rising from the East, I was covered by the shadow of
our house. I did not expect much to see in the field of view, only a little double
star. But much to my surprise the field was full of little sparks. I guess my
telescopic LM was about mag 11.5 at x63. The nelm was about mag 4.5 under a dark
blue sky. Even the telescopic sky appeared blue to me. I tried not to overdo the
colors. I have a hard time detecting colors in stars. So here is my little sketch of
Albireo. I hope you like it. (edit: the sketch has been reworked, once Sheliak was
finished. This to adapt the relation in brightness a bit.)

Date : August 29, 2007
Time : 21.00UT
Scope : Skywatcher 102/500
Vixen LV zoom at 8mm
Power : x62
FOV: 50′
Filter : none
Seeing : 3.5/5
Transp. : 2/5
Nelm : 4.5
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.
Rony De Laet

http://www.geocities.com/rodelaet

The Other Double Double in Lyra

Last evening I was out observing with a telescope and thinking about how another
summer is ending and the fall season is upon us. With the exception of the month
of August which was mostly cloudy and rainy, the summer here was a good one for
observing. The first three weeks of September has been a welcome return to the
good observing nights like I experienced in June and July. At a public open
viewing night this past Friday I was showing the attendees the famous double
double ( Epsilon 1and 2 Lyrae). At the end of the evening I realized I had
forgotten to show them the other double double in eastern Lyra with the wider
separation and nearly parallel components rather than perpendicular as with
epsilon 1 and 2. I have never sketched this combination of double stars so I
decided to do just that and maybe next time I won’t forget to point out this view.
I am not a binocular observer but these stars would I am sure look great and split
nicely in a pair of astronomical binoculars. The northern pair of stars are designated
Struve 2470 they are both white stars at magnitudes 6.6 and 8.6 at a position angle
of 271°. The separation of this pair is 13.4” of arc. The other double pair 11 minutes
to the south is Struve 2474; this pair of pale yellow stars glow at magnitude 6.7 and 8.7.
they are separated by 16” of arc and are in position angle 262°. This is the way they
looked to me at the telescope eyepiece. These stars are about 19hrs. 9min.
Right Ascensionand +34° 40min Declination. Both pair fit nicely in one field of
view and are easy to split.

Sketching:

Date and Time: 9-20-2007, 2:25-2:50 UT
Scope: 10” f/5.7 Dobsonian. 21mm eyepiece 70x
8”x12” white sketching paper, B, 2B graphite pencils, scanned and inverted, star
brightness adjustment using Paint
Seeing: Pickering 7/10
Transparency: above average 3/5
Nelm: 4.5

Frank McCabe

Two in the midst of hundreds

Delta Lyrae, Stephenson 1

A drawing of a double star that was supposed to be a walk in the park turned out to
be a lot more challenging. This moonless night was filled with plenty of stars. So
was the field of view around Delta Lyrae. Countless milkyway stars were scattered
like pinpricks in the sky. Leaving them out of the sketch was no option. I also read
that Delta Lyrae is part of a sparse little cluster called Stephenson 1. I had a
hard time to recognise the grouping as a cluster. Here is the sketch.

Date : September 4, 2007
Time : 21.00UT
Scope : Skywatcher 102/500
Meade 4000 SP 26mm
Power : x20
FOV: 150′
Filter : none
Seeing : 3.5/5
Transp. : 3/5
Nelm : 5.3
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.
Rony De Laet

http://www.geocities.com/rodelaet

Ice Blue Vega

Here is a simple sketch of the dazzling light from Vega. A mag zero star fills the
field with a radiant glow. It sure ruins my night vision, making it hard and almost
painfull to look for faint companions. It is my impression that 3 little stars
suround Vega. It’s a daunting task to find a sweet spot on my retina for the fainter
stars, while Vega tries to burn a hole in my eye. I could not resist but to hold my
hand against my head to darken the eyepiece as if a streetlight was interfering with
my observation. Useless of course. I also tried to show the secondary spectrum of
the (achromatic) Skywatcher around Vega. I hope it makes sense.
Date : September 4, 2007
Time : 22.00UT
Scope : Skywatcher 102/500
Vixen LV Zoom at 8mm
Power : x63
FOV: 48′
Filter : none
Seeing : 3.5/5
Transp. : 3/5
Nelm : 5.3
Sketch Orientation : N up, W right.
Digital sketch made with PhotoPaint, based on a raw pencil sketch.
Rony De Laet

http://www.geocities.com/rodelaet