Double Star Category

Photograph of Winter Milky Way over Sunset Craterwith sketches of deep sky objects in the area. Move mouse over sketch above to see where each deep sky object resides.Click image for larger version. Click here for larger version without call-out lines.. . . . . Other Print Versions: Vertical...

2 Comae Berenices (Struve 1596)

Sketch of 2 Comae Berenices / Struve 1596Click image to view larger version. Observation Notes: The color in this pair reminded me of Gamma Leporis with a white primary and dull orange-yellow companion. Sissy Haas sees yellow-white/green-white. Others see the secondary as "rosey" (Webb), "lilac tinted" (Smyth), "deep yellow" (Hartung)...

3 Centauri

Observation Notes: This bluish pair gave the appearance of sky blue for the primary and blue-gray for the secondary. My estimate for PA was 115°. Seeing was very poor in the area, and made the diffraction rings impossible to see clearly. My best guess was 5-10 arc seconds. Actual...

4 Centauri (Herschel 51)

Observation Notes: After a blustery evening attempting to observe at Cinder Hills Overlook (Sunset Crater National Monument), I gave 4 Centauri a try. At low power, this double appeared to have a cream colored primary and a blue-gray secondary. At 240X however, the color of the primary appeared to...

8 Lacertae (Struve 2922)

Observation Notes: There was a lot of color in this beautiful star-filled view. The primary took on a green color with a blue secondary. Further to the south was a faint, possibly red-orange component. At the west end of the view was another, brighter blue star. Subject8 Lacertae (STF...

12 Lyncis (Struve 948)

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Sketch of 12 Lyncis (Struve 948) Observation Notes: 12 Lyncis was a great triple star system. Color contrast was very nice--the primary appeared pale yellow, with a pale blue secondary hugging it. The tertiary appeared to be dull orange. They made for a very striking sight at 120X and...

19 Lyncis (Struve 1062)

Sketch of 19 Lyncis (Struve 1062) Observation Notes: The two main stars in this attractive multiple provided me with another unusual color contrast. The primary appeared yellow next to a rich blue secondary. Both stars are B class, so the appearance of the primary is illusory. I made measurements...
The June issue of Astronomy Now is now available. This month's column features the colorful double, Struve 2259 in Hercules. Subject:Struve 2259 Issue:June 2009 Astronomy Now Basic Media:White ink marker, white pastel and colored pastel pencil on black paper. Featured Technique:Using white ink along with white and colored pastel to...

24 Comae Berenices (Struve 1657)

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Click above image for larger version Observation Notes: This widely spaced double in Coma Berenices is a real showpiece, particularly when seeing conditions are good. The primary is a deep yellow-orange in color with a rich blue secondary hovering to the west. The steadily shimmering diffraction rings made them look...

32 Camelopardalis (Struve 1694)

Observation Notes: This was a little fun to line up, so near the celestial pole. Once I got there, I sighted a wide pair of pale blue stars of nearly equal magnitude. I marked them about 45 arcseconds apart with a PA of 305 degrees. Actual values are 22...

35 Sextantis (Struve 1466)

Sketch of 35 Sextantis (Struve 1466)Click image to view larger version. Observation Notes: This nice yellow-orange/pale blue binary was also seen as citrus-orange/blended-blue-green (Haas) and topaz-yellow/smalt-blue (Smyth). The faint C star showed to the southwest, but I didn't realize it was a component, so I didn't measure it. Subject35 Sextantis...

36 Andromedae (Struve 73)

Click image for larger version Observation Notes: This double emitted a warm yellow light and was closely spaced. Seeing was not great, so I had some trouble estimating the separation of the two stars. There was clearly a black gap between the two, and the best I could tell, the...

38 Lyncis (Struve 1334)

Click image for larger version Observation Notes: My first attempt at measuring this double star on April 10th was foiled by a sudden deterioration in seeing. So I hit it again on the 12th when I was able to enjoy the interesting color contrast of this close double under more...

40, 41 Draconis (Struve 2308)

Observation Notes: During a trip to Oklahoma, I brought the telescope along in hopes of doing some observing. But with clouds and constant wind, I got very little done. This was the one observation I was able to sketch and present. The A and B stars of this multiple...

49 Leonis (Struve 1450 / TX LEO)

Sketch of 49 Leonis / Struve 1450 / TX LEOClick image to view larger version. Observation Notes: Seeing conditions weren't the greatest this evening, so I couldn't snag this one until it approached culmination. I was able to finally spot the speck of the secondary emerging from the primary's diffraction...

54 Leonis (Struve 1487)

Observation Notes: 54 Leonis showed a beautiful color combination to my eye. The primary appeared as a pale blue-green next to a deep blue secondary. Once again, I'm seeing a greenish contrast effect on a primary instead of the secondary. What can I say? I'm still trying to figure...

61 Cygni (Struve 2758)

Observation Notes: This is one of seven double star sketches I submitted to Sky and Telescope for an article in the September 2006 issue, More of My Favorite Double Stars by James Mullaney. I had already observed five of them, but 61 Cygni was a fresh observation. It was...

65 Piscium (Struve 61)

Click image for larger version Observation Notes: This double star pair is of equal brightness, and in my 15 cm reflector, appeared to be separated by the radii of about 3 diffraction rings, or about 3.7 arc seconds. I measured PA at 292 or 112 degrees (depending on which star...

83 Leonis (Struve 1540)

Sketch of 83 Leonis / Struve 1540Click image to view larger version. Observation Notes: This yellow and red-orange pair consists of a G7V primary and K4V secondary. Sissy Haas sees them as yellow-white and gray. They make a striking, low-power, double-double with nearby Tau Leonis. Subject83 Leonis (Struve 1540 /...

88 Leonis (Struve 1547)

Sketch of 88 Leonis / Struve 1547Click image to view larger version. Observation Notes: 88 Leonis is a high proper motion pair (378 mas/yr) with a coppery orange primary next to a colorless secondary. Sissy Haas sees it as bright white paired with a tiny speck. Smyth saw topaz yellow...

90 Leonis (Struve 1552)

Sketch of 90 Leonis (Struve 1552)Click image to view larger version. Observation Notes: The trio of 90 Leonis appeared sky blue, cream, and dull orange. Sissy Haas sees yellow, yellow, gray and Smyth saw silvery-white, purplish, pale-red. Subject90 Leonis (STF 1552 / ADS 8220) ClassificationMultiple Star Position (J2000)*Sextans [RA: 11...

94 Aquarii (Struve 2998)

October 9, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: The primary star in this double is orange-yellow, with what is probably a white secondary. But the secondary appears dirty gray-violet in...

95 Herculis (Struve 2264)

Sketch of 95 Herculis (Struve 2264)Click image to view larger version. Observation Notes: 95 Herculis/Struve 2264 is another beautiful, bright pair in Hercules. The primary was sky blue with a hint of green and it's companion was a rich, golden yellow. The diffraction pattern looked great. Rings buzzed out to...

AG 342 (TYC1978-179-1&2)

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Sketch of AG 342Click image to view larger version. Observation Notes: AG 342 is an orange-yellow/dull-orange pair, located at the thruster end of a star-destroyer asterism. The diffraction pattern was faint and difficult to pin down. This is a high proper motion pair (190 mas/yr) of K3V stars. SubjectAG 342...

Alpha Canum Venaticorum (Struve 1692)

Observation Notes: This double consists of a pale blue primary with an elusively colored companion. The secondary appeared slightly yellow-orange. SubjectAlpha Canum Venaticorum (âˆ'1692) ClassificationDouble Star Position (J2000)Canes Venatici [RA: 12:56:02 / Dec: +38:19:05]* Position Angle*228° (1822) Separation*19.3" (1984) Magnitudes*2.9/5.6 Spectral Types*A0/F0 Date/TimeSEP 03, 2006 - 09:00 PM MST...

Alpha Capricorni (Struve 51)

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October 9, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: This doubly was very close to a brilliant star. The primary is orange. The secondary is white. PA appears to be 240°...
Click image for larger version Observation Notes: The fussy seeing provided a beautiful view of this brilliant double. The diffraction patterns shimmered and danced, adding a bit of challenge to viewing the pair, but also providing a mesmerizing, speckled light show. The primary of Castor appeared bright white while its...
Sketch of Alpha Herculis (Rasalgethi/Struve 2140)Click image to view larger version. Observation Notes: Rasalgethi is a fantastic, colorful double. The bright primary shone a yellowish orange with--get ready for it--a sage green secondary. The diffraction pattern was captivating in better than normal seeing. SubjectAlpha Herculis (Rasalgethi / STF 2140 /...

Alpha Leonis (Regulus / Struve 6)

Observation Notes: Regulus makes for a wide double with a brilliant blue-white primary that gave a reddish purple appearance to its G-type secondary star. Separation appeared to be 1/3 of the field of view, or about 240 arc seconds. The actual value is 178 arc seconds (or about 1/4...

Alpha Librae (SHJ 186)

Observation Notes: This is a very wide double and looks great at low power. The primary was pale blue with a dull orange secondary. SubjectAlpha Librae (SHJ 186) ClassificationDouble Star Position (J2000)Libra [RA: 14:50:52.6 / Dec: -16:02:30]* Position Angle*314° (1823) Separation*231" (1823) Magnitudes*2.75 / 5.15 Spectral Types*A3IV / F4IV...

Alpha Piscium (Struve 202)

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Click image for larger version Observation Notes: The first diffraction ring on the primary of this close double appeared to fall just short of bisecting the center of its companion. I estimated a separation of 1.4 arc seconds; however, Brian Workman's Double Star Calculator gives 1.78 arc seconds. My PA...

Alpha Scorpii (Antares / GNT 1)

Click image for larger version. Observation Notes: The goal of splitting the double star, Antares, has been tempting me for a while. I never have the sort of seeing conditions that would make it a nice clean observation. So I gave it a try on this less-than-perfect evening, and was...
Click image for larger version Observation Notes: Just because I've known Polaris was a double star all along doesn't mean I've taken the opportunity to point my telescope at it. Until now. And it turned out to be a nice one. The difference in magnitude as fairly large, but because...

Beta Capricorni (Struve 52)

Click image for larger version. Observation Notes - May 12, 2008 Before submitting the sketch of this double for an upcoming observing article, I noticed an obvious error in the orientation of the entire field. Whenever the alignment of the double is very close to north, south, east or...
Digital Illustration of Albireo (Beta Cygni / Struve-A 43)Click image to view larger version. Observation Notes - October 15/16, 2011: Albireo gets its startling beauty not only from its striking color contrast, but also from the rich star field that surrounds it. I wanted to make an updated sketch that...

Beta Lyrae (Struve 39 and Burnham 293)

Observation Notes: Although I was originally looking for a double here, there are two additional stars to the north of the primary that are included as part of Burnham 293. The primary, for some reason, appeared brilliant green in color--emerald green in fact. The secondary to the south was...

Beta Monocerotis (Struve 919)

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Sketch of Beta Monocerotis (Struve 919)Click image to view larger version. Observation Notes: Beta Monocerotis is a great multiple star. At low power, it appears to be a double star, but bumping up the magnification shows the eastern component to be a close double itself. Despite all three components being...
Move mouse over upper image for labels. Click here for a large (51K) version of this sketch. Observation Notes This was a surprisingly beautiful comet! The coma was bright and strongly condensed. I did not detect a pseudo-nucleus however. The slender gauze of an ion tail flowed toward the...

C/2006 W3 (Christensen) - OCT 25, 2008

Move mouse over sketch above to view labels. Click image for larger version. Observation Notes: Comet 2006 W3 was discovered on November 18, 2006 by E. J. Christensen with the Catalina Sky Survey. It has been corkscrewing its way along the northern Milky Way since then, heading for a...

Delta Boötis (Struve 27)

Observation Notes: The constellation of Boötes is chock full of bright, colorful double stars. Delta Boötis is a wide double that presented me with an interesting color scheme. PA appeared to be about 78 degrees, and separation about 144 arcseconds. Actual values are 78 degrees (Yes!) and 104.9 arcseconds....

Delta Corvi

Observation Notes: Have you ever seen a brownish-gray star? Probably not if it wasn't plunked down right next to a bright, colorful companion. This pair featured a pale sky blue primary with a secondary that appeared brownish-gray by comparison. According to the Catalog of Stellar Spectral Classifications (Skiff, 2005),...

Delta Geminorum (Struve 1066)

Click image for larger version Observation Notes: This double provided a great contrast in magnitude. The secondary was far enough away to not be heavily overpowered by the primary. The 3.5 magnitude primary appeared pale yellow, and the 8.5 magnitude secondary hinted at a dull red color. Since my measurements...

Delta Orionis (Struve 14)

October 12, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: This is a wide double with a bright, blue, southern component. SubjectDelta Orionis (Mintaka / 34 Ori / Struve 14) ClassificationMultiple Star...

Delta Serpentis (Struve 1954)

Sketch of Delta Serpentis (Struve 1954) Observation Notes: Over the last couple hundred years, the stars in this binary system have been moving clockwise in relation to one another by about 50 degrees. The WDS 1782 measurement was 227 degrees at 2.5 arcseconds. I measured 183 degrees with a...

Double Star Sketch Update

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I haven't been able to get out for any observing recently. But I have been up to something. In case you hadn't noticed--and I know you have--I'm working on a double star project right now. In the process, I felt the need to come up with a consistent method for...
Table of Contents Introduction Step 1 - The Observation Step 2 - Sketching The View Step 3 - Scanning, Inverting and Cleaning Up the Sketch Step 4 - Softening Star Edges Step 5 - Adjusting contrast Step 6 - Adjusting White Star Cores Step 7 - Adding Color Step 8...
Step 4 - Softening Star Edges To lay the groundwork for adding color to the stars, I like to soften their edges a bit. The coloring method I use causes color to adhere to varying shades of gray, but leaves the white areas alone. If the star has a pretty...
Step 7 - Adding Color Now comes the fun part--aw heck, it's all fun, right? Anyway it's time to colorize the stars as you described them in your sketch or notes. Grab a soft paint brush that is slightly larger than the star, set the paint brush to "color" mode,...
Step 8 - Adding Additional Glow This last step is a bit of a personal preference. I like to add an additional soft glow around brighter stars to enhance the sense of brilliance. To do this, select a soft brush that is 2 to 3 times the diameter of the...
Observation Notes - June 10, 2012: I made a new observation of Izar tonight and confirmed what I suspected: this is my favorite double. The six-inch scope does a perfect job showing off the amazing diffraction pattern. The blue secondary buzzing in the midst of the orange-yellow pattern is...

Epsilon Hydrae (Struve 1273)

Observation Notes: This was a great double to observe. The primary is a bright, third magnitude pale yellow star with a much fainter seventh magnitude, blue-gray companion resting right up against it. When the seeing was choppy, this secondary disappeared into the overpowering wash of yellow. I thought it...
The 2006 sketch has gotten a lot of mileage and I really needed to re-observe, redraw and measure the double double. I had some confusion when comparing my measurements with the WDS later. I measured 172 degrees PA for AB-CD. However, the WDS listed 182 degrees for 2010 and...

Epsilon Monocerotis (Struve 900)

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Sketch of Epsilon Monocerotis (Struve 900)Click image to view larger version. Observation Notes: Epsilon Monocerotis resides in a populous star field. Color was subtle, and it seemed that the A8 primary was pale yellow while the F5 secondary appeared steel blue-gray. Other observers see the colors as follows: Smythe: Golden...

Epsilon Pegasi (South 798)

October 17, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: The primary star was a brilliant yellow with a tinge of orange. The secondary color was either white or blue. It was...

Eta Cassiopeiae (Struve 60)

Sketch Refinement Above is the cleaned up sketch that was submitted to Sky and Telescope for the September 2006 issue. August 1, 2005 Observation Observation Notes: This was a nice close double. The bright primary was on the southeast side with a deep orange secondary on the northwest side....

Eta Persei (Struve 307)

October 18, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: The primary star was a brilliant orange, with a blue-white secondary that picked up a hint of violet from the contrast. The...

Gamma Andromedae (Struve 205)

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Sketch Refinement Above is the cleaned up sketch that was submitted to Sky and Telescope for the September 2006 issue. August 2, 2005 Observation Observation Notes: This beautiful, close double star had a bright yellow primary and deep blue secondary. The contrast almost made the secondary look violet. My...

Gamma Arietis (Struve 180)

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Sketch Refinement Above is the cleaned up sketch that was submitted to Sky and Telescope for the September 2006 issue. August 7, 2005 Observation Observation Notes: This was a stunning pair. They were so close in magnitude, I couldn't tell the primary. At low power, both looked light blue....

Gamma Ceti (Struve 299)

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Click image for larger version Observation Notes: At the neck of the circlet of Cetus lies a close double star with a noticeable difference in magnitude. The primary star is about 9 times as bright as its companion and appeared white to me. Its spectral class of A2 agrees fairly...

Gamma Delphini (Struve 2727)

Sketch Refinement Above is the cleaned up sketch that was submitted to Sky and Telescope for the September 2006 issue. December 12, 2005 Observation Observation Notes: This was a beautiful yellow/white combo. The yellow star was the primary. PA appeared to be 280° with a separation about 9 diffraction...

Gamma Leonis (Algieba / Struve 1424)

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Observation Notes: This was a stunning, pair of close orange-yellow stars. Their color reminded me of our own sun's hue during a clear, warm sunset. PA appeared to be about 130 degrees, which compares with the 1990 value of 123 degrees from the WDS Catalog. The stars were separated...

Gamma Leporis (Herschel 40)

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October 18, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: This is a beautiful trio. The middle star is a deep orange. The stars look best with the 32 mm eyepiece--very brilliant,...

Gamma Velorum (Dunlop 65)

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Binocular Observation - February 26, 2007: Click above image for larger version (20K). I made this binocular observation from my front doorstep with moonlight strongly lighting up the field. The primary of Gamma Velorum was the brightest star in the murky view near the horizon, and gave off a blue...
Move mouse over sketch above to see comparison detail illustration from January 2007. Click the image for a larger version. About 38 light years away in the constellation Virgo, this pair of twin stars orbit one another once every 169 years. When I last observed them in January 2007,...

Iota Bootis (Struve 26)

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Click image for larger version Observation Notes: I think Boötes is my favorite constellation for doubles. Iota Boötis is not one of the showstoppers, but it's still an enjoyable color tester. At low power, I saw the primary as yellow with a dull blue secondary. At high power, the colors...

Iota Cancri (Struve 1268)

Observation Notes: Iota Cancri was a wide double with a brilliant yellow primary and a rich blue secondary. The PA appeared to be 315° (actual WDS value is 307°). Separation looked like about 55 arc seconds, but the WDS value is actually 30.4 arc seconds. SubjectIota Cancri (STF 1268)...

Iota Leonis (Struve 1536)

Sketch of Iota Leonis (Struve 1536)Click image to view larger version. Observation Notes: Iota Leonis was ridiculously difficult in poor seeing--only resolving for moments as a dim fuzzball that was fainter than the primary's flickering diffraction pattern. They both appeared colorless. Smyth saw pale yellow and light blue while Hartung...

Iota Orionis (Struve 752)

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October 18, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: Main component is quite bright and blue. The other two members are to the southeast and east. The closest one is much...

Iota Trianguli (Struve 227)

October 17, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: This little booger took me by surprise. At low power, it looked like a single star and I thought maybe I was...

Kappa Boötis (Struve 1821)

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Observation Notes: This was a subtle and uneven pair. The PA appeared to be 225° with a separation that was obout 1/36 of the 12 arc minute FOV--which works out to about 20 arc seconds. Actual values are 236° and 13.4 arc seconds. The primary appeared pale yellow with...

Lambda Arietis (Herschel 12)

October 18, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: The primary star was yellowish with a blueish secondary. They made a good pair at low power (38X). The 240X view wasn't...

Lambda Orionis (Struve 738)

October 12, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: While finding in the 32 mm EP, the double didn't show up. Meissa sits at the north end of a trio of...

Messier 40

Observation Notes: I wasn't planning on doing a full-blown observation and sketch of M40 when I did. Which is to say: at the All Arizona Messier Marathon. I hadn't done any research on it before heading 250 miles south to Arizona City. When the time came to find it,...

Measuring Double Stars - Page 1 of 3

A few months ago, I invested in a Meade 12 mm Astrometric Eyepiece that I could use in measuring double stars. I calibrated the eyepiece scale in June, and have used a few times since them. I'm definitely at the novice stage of using this eyepiece to measure doubles, but...
7) Insert the barlow through the hole in the protractor disc to check for fit. The fit should be snug and some twisting and wiggling may be needed to insert it the first time. If it is too snug, use your knife to evenly trim out a bit more material...
Calibrating the separation scale 1) Pick several stars from a list of calibration doubles. The table on page 3 of Ronald Charles Tanguay's article "Observing Double Stars for Fun and Science" is an excellent resource. Look for wider doubles to help reduce estimating errors. 2) Rotate the eyepiece so that...

Mu Bootis (Struve 28 / 1938)

Click image for larger version. Observation Notes: I wasn't prepared for what a pleasant surprise this 'double' star was at high magnification when the B star turned out to be a close double itself. The yellow primary appeared to be separated from the BC combo by about 120 arcseconds. The...

Mu Crucis (DUN 126)

Observation Notes: While enjoying the view from the summit of Haleakala on Maui, I was able to make a binocular observation of the wide double, Mu Crucis. This wide double was a nice binocular target and was only difficult to split when the wind was shaking my lightweight tripod....

N Hydrae

Observation Notes: I was unable to tell which star was the primary, so the PA appeared to be either 203° or 157°. Separation seemed to be about 10 arc seconds. WDS values from 1783 are 210° and 9.3 arc seconds. That's a pretty old measurement, and I'm not sure...

NGC 1502 and Struve 485

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Click on image above for larger version (86K). Observation Notes: This little knot of stars was a stop I made while cruising through Perseus, Cassiopeia and Camelopardalis. As I navigated to the area, I ran into Kemble's Cascade. It was a pleasant surprise--I'm not very familiar with the area...

NGC 2169 and Struve 848

Sketch of NGC 2169 (The 37 Cluster) and Struve 848 Move mouse over image to view label.Click for larger version. Observation Notes So many old sketches, so little time--this one is over a year old. NGC 2169 really did look like an upside-down, angular #37. I plotted 19 stars...

NGC 7008 (Fetus Nebula) and HJ 1606

Observation Notes: This fascinating planetary nebula was pleasantly large, and easy to spot with my low power eyepiece at 37.5X. I could see no color in the nebula, but there was some color right next to it in the double star HJ 1606. The primary of this double was...

Otto Struve 525

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October 17, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: This pair exhibited beautiful color at low power. The brighter southern star was yellow-orange, while the norther was blue. It was a...

Pi Boötis (Struve 1864)

Observation Notes: This appeared as a pale blue primary with a subtly colored secondary that seemed to be off-white in color. The were separated by about 5 1st-diffraction-ring radii. SubjectPi Bootis (âˆ'1864) ClassificationDouble Star Position (J2000)Bootes [RA: 14:40:43.5 / Dec: +16:25:06]* Position Angle*109° (1988) Separation*5.6" (1988) Magnitudes*5.0 / 5.9...

Pi Lupi (HJ 4728)

Click above image for larger version Observation Notes: If you live near 35 degrees North Latitude, and enjoy overcoming the adversity of observing far southern objects, you may want to give the double star Pi Lupi a try. This pair rises no more than 8 degrees above the horizon where...

Psi-1 Piscium (Struve 88)

Observation Notes: Color was pretty subtle here. The southern star was pale blue and the northern star picked up a greenish yellow appearance. Magnitudes of the two brightest stars were too similar to tell apart. A third fainter star appeared toward the east southeast. SubjectPsi-1 Piscium (STF 88) ClassificationMultiple...

Rigel (Beta Orionis / Struve 668)

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Sketch of Rigel (Beta Orionis / Struve 668)Click image to view larger version. Observation Notes: Rigel really makes a beautiful pair. The effect of the brilliant primary glaring across its subdued companion is striking. The secondary does hold its own though, and even though the diffraction spikes cut straight across...

Sigma Cassiopeiae (Struve 3049)

October 18, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: This is the closest AL Double I've observed so far. Both stars were white. The secondary appeared to sit at 330° PA,...

Sigma Coronae Borealis (Struve 2032)

Click image for larger version. Observation Notes: Sigma Coronae Borealis was a beautiful multiple star. The primary was a rich yellow with a reddish purple secondary right next to it. A third component (the D star) lingered to the east. The two closest stars, A and B, were separated by...

Sigma Orionis (Struve 762)

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October 12, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: A neat multiple star area. There was a triple star at center with a blue component on the west side. The northeast...

Struve 331

October 18, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: The seeing was poor in this part of the sky and the color of the stars hard to determine. If anything, the...

Struve 747

October 18, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: These 2 stars appear blue and are the brightest in the field. SubjectStruve 747 (ADS 4182) ClassificationDouble Star PositionOrion [RA: 05 35...

Struve 1369

Sketch of Struve 1369Click image to view larger version. Observation Notes: Color in Struve 1369 appeared best at 120X. The primary was yellow, with a dull red-orange component to the south-southeast, and a dull gray-orange component further to the north-northwest. SubjectSTF 1369 (DI Lyncis / ADS 7438) ClassificationMultiple Star Position...

Struve 1374

Sketch of Struve 1374Click image to view larger version. Observation Notes: The primary in Struve 1374 glows a pale yellow next to a dull blue secondary. A wide pair of stars lies about 7 arc minutes to the southwest. SubjectSTF 1374 ClassificationMultiple Star Position (J2000)*Leo Minor [RA: 09 41 21.9...

Struve 1521

Sketch of Struve 1521Click image to view larger version. Observation Notes: The diffraction patterns were subtle, and color elusive. The primary appeared palest blue, and I couldn't shake the impression of a dull orange secondary. SubjectStruve 1521 (STF 1521 / ADS 8105) ClassificationDouble Star Position (J2000)*Leo [RA: 11 15 21...

Struve 1575

Sketch of Struve 1575Click image to view larger version. Observation Notes: This attractive yellow-orange and blue-gray double (K0/F5V) was recorded as white/white by Phillips and orange/white by Harshaw. SubjectStruve 1575 (STF 1575; ADS 8327) ClassificationDouble Star Position (J2000)*Leo [RA: 11 51 57.6 / Dec: +08 49 48] Position AngleAB: 211°...

Struve 1604

Digital Illustration of Struve 1604 Move mouse over image to view labelsClick for larger version. Observation Notes: I observed this triple star nearly a year ago for Sue French's May 2009 Deep Sky Wonders column. I was out at Sunset Crater National Monument so I could get a good...

Struve 1659 - The Stargate

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Move mouse over sketch above to view labels. Click image for larger version. Observation Notes: While making my way to M104 last week, I ran across this startling multiple star. I had read about "The Stargate", but wasn't counting on seeing it that night. The nearly symmetrical arrangement of...

Struve 1669

Observation Notes: About a degree and a half south of the Sombrero Galaxy, M104, you'll find the multiple star, Struve 1669. The main attraction here is a pair of 6th magnitude F class stars. When observing them, don't forget to take in a third, tenth-magnitude star 1 arc minute...

Struve 1835

Observation Notes: This close double had a primary that was very slightly blue, with a secondary that appeared purplish gray. They appeared to be separated by 5 to 6 first-diffraction-ring radii. SubjectStruve 1835 (âˆ'1835) ClassificationDouble Star Position (J2000)Bootes [RA: 14:23:23 / Dec: +08:26:47]* Position Angle*193° (1989) Separation*6.2" (1989) Magnitudes*5.1/6.9...

Struve 2194

Sketch of Struve 2194Click image to view larger version. Observation Notes: Struve 2194 consists of a 6.5/9.3 magnitude pair separated by 16 arc seconds at 8°PA. I measured this pair at 18 arc seconds and 7°. There is also another 9th magnitude C star further south that I plotted, but...

Struve 2259

Sketch of Struve 2259Click image to view larger version. Observation Notes: Struve 2259 hit the top of my double star favorites the moment it came into view. It is a beautiful gold/blue pair at the heart of a starry bow-tie dominated by the brilliant white Nu Herculis. It looked best...

Struve 2306

Click image for larger version Observation Notes: Nestled in the rich star fields between the Eagle and Swan Nebulae lies a fascinating multiple star. Struve 2306 was surprisingly colorful for a trio of 8th and 9th magnitude stars. The primary was a strong yellow with a rich blue companion to...

Struve 2404

Observation Notes: This was a very subtle pair. Seeing was poor and the reddish-orange primary seemed to rub its color off on the secondary. SubjectSTF 2404 ClassificationDouble Star Position (J2000)Aquila: [RA: 18:50:45.5 / Dec: +10:58:35]* Position Angle*183° (1822) Separation*3.6" (1822) Magnitudes*6.9/8.0 Spectral Types*K5III/K3III Date/TimeSEP 04, 2006 - 1:10 AM...

Struve 3053

Observation Notes: This is one of seven double star sketches I submitted to Sky and Telescope for an article in the September 2006 issue, More of My Favorite Double Stars by James Mullaney. I had already observed five of them, but Struve 3053 was a new observation. It was...

Tau Leonis (Struve-A 19)

Sketch of Tau Leonis / Struve-A 19Click image to view larger version. Observation Notes: I saw this widely spaced, colorful double as Orange-yellow and blue. Despite a G8 primary and G5 secondary, other observers also pick up the blue color contrast in the companion: 33 Doubles - Tau LEO. Sissy...
Sketch of Tau and 83 Leonis / Struve-A 19 and Struve 1540Click image to view larger version. Observation Notes: This striking double double consists of widely spaced, colorful Tau Leonis (orange-yellow and blue) and 83 Leonis (yellow and red-orange). Subject Tau Leonis (84 LEO / Struve-A 19 / STFA 19)...

Tau-1 Hydrae (HJ 1167)

Observation Notes: This double star presented an interesting color contrast compared to the actual spectra. The primary appeared pale yellow, with a fainter blue-gray companion. The primary is F6V, which is believable, but according to the 13th General Catalogue of MK Spectral Classification (Buscombe 1998), the secondary is a...
October 18, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: Even in poor seeing, the trapezium is spectacular. The A-D stars were simple to spot, with the C star being the brightest....

Theta 2 Orionis (Struve 16)

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October 18, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: These 3 stars near the trapezium are widely spaced, and appear as bright or brighter than the trapezium's C star. SubjectTheta 2...

Theta Serpentis (Struve 2417)

Observation Notes: Poor seeing chopped the view up a bit on this double. The primary appeared light blue with a subtly yellow secondary. Both stars are A5V however. PA appeared to be 110° with a separation about 30 arc seconds. Actual values are 104° and 22.3 arc seconds. SubjectTheta...

V Hydrae (Burnham 1428)

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Click image for larger version Observation Notes: I unexpectedly ran across this beautiful double while tracking comet C/2007 W1 (Boattini). The rich, red carbon star primary jumped out at me and I couldn't resist giving it a closer look. The primary was a rich, red--almost like seeing a 'hot pixel'...

Xi Bootis (Struve 1888)

Observation Notes: This was a pale yellow primary with a dull red-orange secondary. They appeared to be separated by about 5 1st-diffraction ring radii. SubjectXi Bootis (âˆ'1888) ClassificationDouble Star Position (J2000)Bootes [RA: 14:51:23.4 / Dec: +19:06:01]* Position Angle*321° (1997) Separation*6.7" (1997) Magnitudes*4.7 / 7.0 Spectral Types*- Date/TimeSEP 03, 2006...
Sketch of Xi Scorpii (Struve 1998) and Struve 1999Click image to view larger version. Observation Notes: There are a number of double-doubles scattered across the sky. Although Epsilon Lyrae may be the best known, there's really some great competition out there. Xi Scorpii/Struve 1998 and its southern counterpart, Struve 1999,...

Xi Ursae Majoris (Struve 1523)

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Observation Notes: This close double consisted of two yellow-orange stars very close in brightness. The northeast component was brightest, and both stars were close to riding each other's first diffraction rings. That would put their separation somewhere between one and two arcseconds. PA was about 235 degrees. Roughly extrapolating...
Observation Notes: The low power (37.5X) view of Mizar and Alcor provides a nice scale of wide and closely spaced doubles mixed with several field stars. The primary of Zeta UMA appeared brilliant blue with what appeared to be a purplish-blue secondary. 80 UMA took on a cyanish blue...

Zeta Aquarii (Struve 2909)

Sketch Refinement Above is the cleaned up sketch that was submitted to Sky and Telescope for the September 2006 issue. September 12, 2005 Observation Observation Notes: These two were so very close and perfectly similar, it was a very cool double. The PA is either 360° or 175°, depending...

Zeta Boötis (Struve 1865)

Observation Notes: This is the closest double I've observed yet. It appeared as a single, slightly elongated star that points west-northwest/east-southeast. PA appears to be either 120° or 300°, depending on which star is the primary. According to notes in the WVDSC, the pair has a 123 year period....

Zeta Cancri (Struve 1196)

Observation Notes: This was a great triple star. The central diffraction discs of the A and B components appeared to just touch at a position angle of about 68 degrees, which works out to a separation of about .9 arc seconds. These 2 stars were pale yellow in color...

Zeta Coronae Borealis (Struve 1965)

Click image for larger version. Observation Notes: This bright double in Corona Borealis provided me with a huge challenge when it came to determining the color of the primary star. At first it appeared cyan, then white, then lime green, before settling at what seemed like pale yellow. Seeing was...

Zeta Lyrae (Struve 38)

Observation Notes: This double was fairly wide--about 60 arc seconds by my estimate. The WDS value from 1835 is 43.7 arc seconds. PA appeared to be about 155° which compares to 150° from the WDS. Color was a bit elusive, but if anything, the primary appeared light yellow with...

Zeta Orionis (Struve 774)

October 12, 2006: To help provide a consistent style for my double star sketches, the above sketch is a digital update to the original sketch. Observation Notes: My first impression was of a wide double with a blue southern component that was much brighter than its southern counterpart. I...

Zeta Piscium (Struve 100)

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Click image for larger version Observation Notes: I had a very difficult time determining color on this double. At low power, the primary appeared pale yellow with a white secondary. At 240X, the color appearance switched from blue/yellow to white/yellow to yellow/blue. I decided to go with the low power...

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