May 12, 2008
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 west, any slop in position angle becomes pretty obvious. So I headed out early this morning for another look and put the astrometric eyepiece on it. The corrected PA and separation can be seen in the illustration above, and the info in the table below. I'm convinced that getting up at 4 in the morning is unhealthy, but the strikingly beautiful color in this double made up for it. It's very wide and definitely appears best at low power. Be sure to look it up with binoculars or a low power eyepiece when Capricornus makes its way into a more agreeable time slot later this summer.
| Subject | Beta Capricorni (STF 52) |
| Classification | Multiple Star |
| Position (J2000) | Capricornus [RA: 20:21:00 / Dec: -14:47]* |
| Position Angle* | A-B: 267°; A-C: 133° [my measurement 2008]
A-B: 267°; A-C: 134° [WDS 1835; 1912] |
| Separation* | A-B: 198"; A-C: 224" [my measurement 2008]
A-B: 205.3"; A-C: 226.6" [WDS 1835; 1912] |
| Magnitudes* | A = 3.4; B = 6.2; C = 9.0 |
| Spectral Types* | A = G9II + B8p; B = A2V; C = F8 |
| Date/Time | MAY 12, 2008 - 04:15 AM (MAY 12, 2008 - 11:15 UT] |
| Observing Loc. | Flagstaff, AZ - Home |
| Instrument | Orion XT8 Dobsonian (203 mm dia./1200 mm F/L) |
| Eyepieces/Mag. | 12 mm Meade Astrometric + 2X Barlow (200X) |
| Conditions | Clear, breezy |
| Seeing | 4/10 Pickering |
| Transparency | NELM Mag 5.0 |
| *References | The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996); Catalogue of Stellar Spectral Classifications (Skiff, 2007); Visual Double Stars in Hipparcos (Dommanget+, 2000); Starry Night Pro Plus 5.8 |
Original Observation Notes:
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.
I'm not sure if this is a triple or not. The primary is brilliant yellow-orange. The secondary is deep blue (PA 265°, Sep. 4'). The tertiary (if that's what it is) is orange (PA 160°, Sep. 5'). All elements were widely spread. The actual listed value of 267° PA/206" (3'26") sep closely matches the measure to the blue secondary.
| Position Angle* | A-B: 265°; A-C: 160° [my estimate 2005] |
| Separation* | A-B: 240"; A-C: 300" [my estimate 2005] |
| Date/Time | SEP 13, 2005 - 12:15 AM MST (SEP 13, 2005 - 07:15 UT) |
| Observing Loc. | Flagstaff, AZ - Home |
| Instrument | Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L) |
| Eyepieces/Mag. | 10 mm Sirius Plossl + 2X Barlow (240X) |
| Conditions | Clear, breezy, 55°F |
| Seeing | 4/10 Pickering |
| Transparency | NELM Mag 4.8 |
Posted by Jeremy at 10:15 PM
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May 2, 2008
C/2007 W1 (Boattini) - MAY 02, 2008
Move mouse over sketch above to view labels. Click image for larger version.
Observation Notes:
Conditions for viewing the comet were much better tonight. Little wind, and improved transparency. As a result, the comet was easier to spot. It was still very soft, but its apparent diameter was closer to 11 arc minutes (compared to 7 arc minutes visible last night). The central condensation was a bit more noticeable as well. Still no suggestion of elongation or a tail. It still fit in the same low power view as V Hydrae, although it was not as nicely placed as the night before. The comet had moved about 50 arc minutes west-southwest since my earlier observation 24.25 hours ago.
| Subject | C/2007 W1 (Boattini) |
| Classification | Comet |
| Position* | 04:40 UT - Hydra: [RA: 10:48:01 / Dec: -21:43:06] |
| Size | Coma: 11 arc minutes diameter |
| Brightness* | ~ 8.0 vMag |
| Date/Time | May 1, 2008, 9:40 PM
(May 2, 2008, 04:40 UT) |
| Observing Loc. | Flagstaff, AZ - Home |
| Instrument | Orion SkyQuest XT8 Dobsonian |
| Eyepieces/Mag. | 32 mm Sirius Plossl (37.5X) |
| Conditions | Clear, calm |
| Seeing | 4/10 Pickering |
| Transparency | Mag 5.0 NELM |
| *Sources | Aerith.net; Starry Night Pro Plus 5.8 | |
*Based on published data.
Posted by Jeremy at 12:25 AM
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May 1, 2008
C/2007 W1 (Boattini) - MAY 01, 2008
Move mouse over sketch above to view labels. Click image for larger version.
Observation Notes:
Although this comet would have benefited from a trip outside of town to get away from the low altitude light pollution, I was still able to find it from my front yard. The comet showed up as a very gradual brightening with a very subtle concentration at the core. It is a slow mover, so I was only able to track about 2 arc minutes worth of movement over the 45 minute span I noted its position. After that, it had sunk too far into the southwestern light pollution to observe further. The best part of the observation was the beautifully red carbon star that shared the low power field with the comet. I couldn't resist researching its identity (V Hydrae) and sketching what turned out to be a double star with a carbon star as its primary: V HYA (BU 1428).
| Subject | C/2007 W1 (Boattini) |
| Classification | Comet |
| Position* | 05:25 UT - Hydra: [RA: 10:51:43.8 / Dec: -21:34:29]
06:10 UT - Hydra [RA: 10:51:36.5 / Dec: -21:34:45] |
| Size | Coma: 7 arc minutes diameter |
| Brightness* | ~ 8.0 vMag |
| Date/Time | April 30, 2008, 9:25 - 10:10 PM
(May 1, 2008, 04:25 - 05:10 UT) |
| Observing Loc. | Flagstaff, AZ - Home |
| Instrument | Orion SkyQuest XT8 Dobsonian |
| Eyepieces/Mag. | 32 mm Sirius Plossl (37.5X) |
| Conditions | Clear, gusty winds |
| Seeing | 4/10 Pickering |
| Transparency | Mag 4.5 NELM |
| *Sources | Aerith.net; Starry Night Pro Plus 5.8 | |
*Based on published data.
Posted by Jeremy at 2:48 AM
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V Hydrae (Burnham 1428)
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' burning in the eyepiece. The secondary is a K0 star, but I didn't detect any color there. Measuring with the Astrometric eyepiece attached to the Dobsonian is a pain, but I came up with a PA of 185 degrees, and a separation of 47 degrees. CCDM (1991) values are 185.7 degrees and 46.8 arc seconds. I'm not sure how widely the carbon star varies in brightness, but since it appeared brighter than nearby 8th magnitude HIP 53050, it seemed to be 7th magnitude this evening. If you like carbon stars or colorful doubles, be sure to give this beauty a look!
Object Information
V Hydrae ranks up there with T Lyrae and Hind's Crimson Star as the reddest stars in the sky with a B-V value of +5.5. It is a variable star, and has two overlapping cycles. The short term cycle varies by about 1.5 magnitudes over a period of 533 days so that it can often be found cycling from 7 to 8.5 magnitude. The second cycle introduces a deep minima every 6500 days that can drop the star's brightness to 12th magnitude (Journal of the Royal Astronomical Society of Canada, Vol. 59, p.245-6). It appears that this star, at the end of its life, is just now ejecting high speed jets that will soon form a planetary nebula. Because this process is so short-lived, V Hydrae offers a unique opportunity for astronomers to gather data on the early phases of the formation of a planetary nebula. Further information about these findings can be seen here.
| Subject | V Hydrae (BU 1428) |
| Classification | Multiple Star, Variable Star, Carbon Star |
| Position (J2000) | Hydra [RA: 10:51:37.2 / Dec: -21:15:00]* |
| Position Angle* | 185° [2008.3 my measurement]
185.7° [1991 CCDM] |
| Separation* | 47" [2008.3 my measurement]
46.8" [1991 CCDM] |
| Magnitudes* | 7.5 / 11.5 |
| Spectral Types* | C6.5 / K0III |
| Date/Time | APR 30, 2008 - 10:30 PM MST (MAY 1, 2008 - 06:30 UT) |
| Observing Loc. | Flagstaff, AZ - Home |
| Instrument | Orion XT8 (203 mm dia./1200 mm F/L) |
| Eyepieces/Mag. | 10 mm Sirius Plössl + 2X Barlow (240X)
12 mm Meade Astrometric EP + 2X Barlow (200X) |
| Conditions | Clear, gusty winds |
| Seeing | 4/10 Pickering |
| Transparency | NELM Mag ~4.0 |
| *References | The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996); CCDM (Catalog of Components of Double & Multiple stars (Dommanget+ 2002); Catalogue of Stellar Spectral Classifications (Skiff, 2007); Starry Night Pro Plus 5.8 |
Posted by Jeremy at 2:27 AM
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April 30, 2008
Identifying Members of Hickson 70
If you are a galaxy cluster chaser, you've probably been rummaging through the Hickson clusters on a regular basis. I am not a seasoned Hickson observer--not even close. The only one I've tracked down is Hickson 92: Stephan's Quintet...and even then, I wasn't able to see all 5 members.
An interesting thing you'll find about the individual galaxies within these clusters is that determining their official designations can sometimes get tricky. Hickson 92 is a relatively bright and well-travelled cluster, and each of its members has an NGC designation. However, other galaxy clusters contain members that are not catalogued with an NGC or IC number. These fainter galaxies need to be referenced by other catalogues, such as PGC, MCG or UGC.
| MCG - Morphological Catalog of Galaxies |
| Details: HyperSky MCG Details |
Contains 30,642 galaxies.
Based on examination of copy prints of Palomar Sky Survey plates down to 15th magnitude. (increasing limit to 16th magnitude was not possible because increase in number of galaxies would be "catastrophic" according to the authors.)
ID takes form of AA-BB-CCC.
AA = Palomar Survey declination zone (+15 = North pole, 0 = equator, -7 = -42°)
BB = Field survey zone (60 divisions at equator, less divisions further from equator)
CCC = Arbitrary ID for each galaxy within the AA-BB field |
| PGC - Principal Galaxy Catalog |
| Details: NASA HEASARC PGC Details |
Cotains about 1 million galaxies.
Consists of confirmed galaxies brighter than b-magnitude 18. Data contains precise (±2 arcsec) coordinates, diameters, axis-ratios, and position angles. (Based on HYPERLEDA database after 2003--was LEDA prior to 2003) |
| UGC - Uppsala Galaxy Catalog |
| HyperSky UGC Details |
Contains nearly 13,000 galaxies.
Based on Palomar Sky Survey. Designed to be complete down to a diameter of 1 arc minute or magnitude of 14.5 on blue plates. |
Because the individual galaxies in these clusters can be so tightly packed and there are so many of them in total, there are times when their identities get swapped or duplicated--even in the most reliable online databases and software.
When preparing the April 29, 2008, post for ASOD, I was trying to apply labels to the seven galaxies visible in Bill Ferris' excellent drawing of Hickson 70. When I got to the galaxy on the east side of the cluster known simply as Hickson 70c, there was a discrepancy in its MCG designation. Several lists at Vizier pointed to a designation of MCG+06-31-065. However, the data at NED that Bill kindly pointed me to, listed the galaxy as MCG+06-31-064. Not a big deal right? Yeah, probably not. But if you're trying to prepare a resource for others to use, and if you're a little bit pedantic, it's hard to let go of a nagging inconsistency once it catches your eye. I'm not an expert at mining these deep databases, so I figured I was probably doing something wrong.
Because Brian Skiff is amazing at being able to see what's going on with problems like this, I fired off an email asking for his thoughts. In less than 45 minutes, I had a reply email--he had pulled out a copy of the MCG prints, and found that indeed, the NED database had incorrectly assigned MCG+06-31-064 to that galaxy, and that it should actually be MCG+06-31-065. As several of the Vizier lists had indicated, the 064 galaxy actually referred to a smaller, fainter galaxy dangling off the northeast edge of its larger, brighter neighbor. Brian fired off a correction notice to the NED administrator, and I was able to re-label Bill's image at ASOD.
Here is a DSS image showing the cluster, and the two galaxies that got confused (see the left--east--side of the cluster). If you're a faint galaxy hunter, you know there's nothing unusual about this. With databases containing tens of thousands of entries, swapped IDs and typos are a digital fact of life. It's a great big universe out there.
Image provided by Aladin Sky Atlas
Posted by Jeremy at 6:19 PM
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April 29, 2008
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 were made with the XT8 Dobsonian, they are not as accurate as I would like. I measured a PA of 231° which compares to a calculated value of 226.7° for 2008.2. Separation was worse. I measured 9.5 arc seconds with the astrometric eyepiece while the spacing of the diffraction rings indicated 4.5 arc seconds. Not too hot. The calculated value for 2008.2 works out to 5.6 arc seconds. I guess if I averaged my two completely different measurement methods I'd be closer, huh?
| Subject | Delta Geminorum (STF 1066) |
| Classification | Multiple Star |
| Position (J2000) | Gemini [RA: 07:20:07.3 / Dec: +21:58:56]* |
| Position Angle* | 231° [2008.2 my measurement]
227° [2008.2 Brian Workman's DS Calculator]
224° [1997 Alzner]
220° [1990 WDS] |
| Separation* | 4.5" [2008.2 my measurement]
5.6" [2008.2 Brian Workman's DS Calculator]
5.88" [1997 Alzner]
5.8" [1990 WDS] |
| Magnitudes* | 3.5 / 8.5 |
| Spectral Types* | F0 / K6V |
| Date/Time | MAR 19, 2008 - 11:10 PM MST (MAR 20, 2008 - 06:10 UT) |
| Observing Loc. | Phoenix, AZ |
| Instrument | Orion XT8 (203 mm dia./1200 mm F/L) |
| Eyepieces/Mag. | 10 mm Sirius Plössl + 2X Barlow (240X)
12 mm Meade Astrometric EP + 2X Barlow (200X) |
| Conditions | Partly Cloudy (cirrus), Gibbous Moon |
| Seeing | 3/10 Pickering |
| Transparency | NELM Mag ~4.0 |
| *References | The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996); CCDM (Catalog of Components of Double & Multiple stars (Dommanget+ 2002); Double stars measurements (Alzner 1998); Catalogue of Stellar Spectral Classifications (Skiff, 2007); Brian Workman Double Star Calculator; Starry Night Pro Plus 5.8 |
Posted by Jeremy at 2:24 AM
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April 13, 2008
Gamma Virginis (Porrima / Struve 1670)
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, they appeared as a single, elongated, pill-shaped star. Last week, April 10, 2008, the diffraction discs were now clearly separated into two distinct stars with no overlap. Position angle had also proceeded about twenty degrees clockwise since my last look.
During my January 2007 observation, I estimated a position angle of 60 degrees. However, the data in Brian Workman's Double Star calculator indicated they should have been 49 degrees. I thought this was strange at the time, since I would probably have guessed 45 degrees if that were the case. Recently, I had a look at some more refined data provided by Brian Skiff. Plugging that into the calculator led to January 2007 value of 58 degrees--much closer to my estimate at the time.
For the April 10, 2008 observation, I was able to put the astrometric eyepiece to use on the pair, and arrived at a position angle of 36 degrees. Skiff's data points to a value of 37.9 degrees. Based on diffraction discs that are not quite touching, I estimated a separation of .92 arc seconds. Skiff's data comes out to .993 arc seconds.
I was excited to see such a pronounced difference since last year. What a privilege to watch the slow dance of this stellar couple.
| Subject | Gamma Virginis (Porrima / STF 1670) |
| Classification | Double Star |
| Position (J2000) | Virgo [RA: 12:41:39.9 / Dec: -01:26:58]* |
| Position Angle* | 36° [My measurement 2008.27]
37.9° [Skiff Data interpolated 2008.27] |
| Separation* | 0.92" [My measurement 2008.27]
0.993" [Skiff Data interpolated 2008.27] |
| Magnitudes* | 3.6; 3.7 |
| Spectral Types* | - |
| Date/Time | APR 10, 2008 - 10:30 PM MST (APR 11, 2008 - 05:30 UT) |
| Observing Loc. | Flagstaff, AZ - Home |
| Instrument | Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L) |
| Eyepieces/Mag. | 12 mm Meade Astrometric Eyepiece+ 2X Barlow (200X) |
| Conditions | Clear, calm, first quarter moon |
| Seeing | 6/10 Pickering |
| Transparency | NELM Mag ~5.0 |
| References | The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996); Brian Workman's Double Star Calculator (Using orbital elements supplied by Brian Skiff) |
*Based on published data.
JANUARY 26, 2007 Observation
Click above image for larger version
Observation Notes:
You'll be taking a dose of your stellar medicine if you observe Gamma Virginis with a 15 cm scope. This close double star appeared pill shaped in my 6 inch reflector. The seeing was great, and the clear, buzzing diffraction rings made for a beautiful impression of this elongated pair. I didn't see any indentation or peanut shape. Coloration was a subtle ivory. The axis elongation appeared to have a position angle of either 60 or 240 degrees depending on which star was the primary. Running the double star's orbital data through Brian Workman's Double Star Calculator gives a PA for January 2007 of 49 degrees with a separation of .75 arc seconds.
The sketch here is a bit different than usual. I have the normal eyepiece circle view, which in this case doesn't serve much purpose other than consistency with my other double sketches. I also include the detail sketch on the lower right that indicates the elongated shape with typified diffraction ring position. What I've added that is new, is a 'frozen' detail sketch in the lower left that gives a snapshot impression of what the diffraction rings and diffraction disc looked like to my eye. You may want to click the image for a larger version to better see this.
| Position Angle* | 60° [My estimate 2007.07]
58° [Skiff ephemeris 2007.07] |
| Separation* | 0.67" [Skiff ephemeris 2007.07] |
| Date/Time | JAN 26, 2007 - 06:00 AM MST (JAN 26, 2007 - 13:00 UT) |
| Observing Loc. | Flagstaff, AZ - Home |
| Instrument | Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L) |
| Eyepieces/Mag. | 10 mm + 2X Barlow (240X) |
| Conditions | Clear, calm, 18° F |
| Seeing | 6/10 Pickering |
| Transparency | NELM Mag ~5.8 |
| References | The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996); Brian Workman's Double Star Calculator (Sixth Catalog of Orbits of Visual Binary Stars by William I. Hartkopf & Brian D. Mason) |
*Based on published data.
Posted by Jeremy at 11:12 PM
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April 7, 2008
110 Messier Objects with 15 x 70 Binoculars
I've had my 15 x 70 Oberwerk binoculars for nearly a year now and have really enjoyed observing with them. In September, I started putting them to use on the Messier catalog. My goal was to see if I could observe all 110 objects from home, with as little fuss as possible. That is: no tripod, very little dark adaptation, and only the most rudimentary sketches. I wanted it to be a fun little blitz, to see how far the binoculars could take me. My main advantage is a very clear sky. So, even though glaring light from nearby industry is reflecting off of every nearby structure, the sky clarity makes up for it if you can shield your eyes for just a few minutes.
When I started last September, the bright, feisty objects in the Summer Milky Way made for easy pickings. By the time spring rolled around though, my binoculars faced an imposing load of galaxies. But they gave way bit by bit. Finally, on April 2nd, I finished a tour of the Virgo Cluster and tracked down my last binocular Messier object: M100.
Several of the objects were very difficult, and would have benefitted from a tripod rather than a reclined lawn chair. I was fooled by unresolved groups of stars a couple times too and had to run back out to re-observe those areas. But with close comparison to the star field and comparison to Starry Night software, I was able to verify all the tough ones. The most difficult objects I noted on my list were: M74, M76, M91, M96, M102, M108, and M109.
Now that I've done it, I hope to attempt a Binocular Messier Marathon one day.
My observing notes are in the table at the end of this entry.
If you want to see the handwritten notes with those rudimentary sketches I mentioned, they can be found in this PDF: Binocular Messier Observation Notes
I have also prepared a blank observing record, in case you would like to use it:
Binocular Messier Observation Form (Letter Size)
Binocular Messier Observation Form (A4 Size)
| ID | Type | AL Rating | Date | Time | Description |
| M1 | SNR | Challenge | 16-Sep-07 | 02:55 AM | Small, soft patch, to NW of Zeta TAU. Actually midway between Mars and Zeta TAU on this night. Great sight! |
| M2 | GC | Easy | 17-Sep-07 | 10:05 PM | Bright, moderately condensed. Lies just north of an arcing group of stars. |
| M3 | GC | Easy | 17-Sep-07 | 08:20 PM | Large, strongly condensed. Forms one corner of a downward pointing long isosceles triangle with 2 other stars. |
| M4 | GC | Easy | 17-Sep-07 | 08:10 PM | First quarter moon was 2 degrees from M4, fun challenge. M4 was a large, soft glow, barely discernible over the background sky/moonglow |
| M5 | GC | Easy | 17-Sep-07 | 08:50 PM | Large, strong condensation. Bright star and a tweaked 'X' shaped asterism were just southwest of it. |
| M6 | OC | Easy | 16-Sep-07 | 09:25 PM | Bright, fully resolved. Parallelogram formed by bright stars, looks much like a small Lyra, including handle. Orange star at east corner. |
| M7 | OC | Easy | 16-Sep-07 | 09:25 PM | Large, fully resolved, fairly condensed. About 20 bright members over about 3 dozen fainter members. Orange star marks sw side of core. |
| M8 | DN+OC | Challenge | 16-Sep-07 | 09:35 PM | Majestic, bright nebula surrounding fully resolved star cluster. Nebula has 2 bright southern patches and a fainter north patch. |
| M9 | GC | Easy | 17-Sep-07 | 09:10 PM | Small, faint, strongly condensed. |
| M10 | GC | Easy | 16-Sep-07 | 09:55 PM | Soft, moderately condensed. |
| M11 | OC | Easy | 16-Sep-07 | 09:30 PM | Looks just like a globular cluster. Strongly condensed and round. Bright. |
| M12 | GC | Easy | 16-Sep-07 | 09:15 PM | Soft, not well condensed. |
| M13 | GC | Easy | 16-Sep-07 | 09:35 PM | Bright, large, broadly condensed core. Forms apex of isosceles triangle with 2 other bright stars. |
| M14 | GC | Tougher | 16-Sep-07 | 10:05 PM | Small, soft, moderately condensed. Forms right angle with a line of three stars to its north. |
| M15 | GC | Easy | 16-Sep-07 | 03:40 AM | Strongly condensed, circular. Sits along side of triangular asterism. |
| M16 | OC+EN | Easy | 16-Sep-07 | 10:30 PM | Grainy star cluster with several brighter members resting over soft, nebulous backdrop. Elongated east to west. 2 bright stars to the south make it look larger. |
| M17 | OC+EN | Easy | 16-Sep-07 | 10:20 PM | Elongated checkmark shaped nebula with east to west alignment and swoosh pointing south on the west end. |
| M18 | OC | Easy | 16-Sep-07 | 10:25 PM | Small circular, partially resolved with some distinct stars lying over soft haze behind. |
| M19 | GC | Tougher | 17-Sep-07 | 09:00 PM | Soft, moderately condensed. Sits beneath a trio of wide doubles that seem to point toward it. Neat context. |
| M20 | N+OC | - | 16-Sep-07 | 09:40 PM | Two-lobed nebulosity. Southern lobe is brightest. Both are centered on bright stars. |
| M21 | OC | - | 16-Sep-07 | 09:45 PM | Grainy cluster, enmeshed in Milky Way field. Strongly condensed core. |
| M22 | GC | Easy | 16-Sep-07 | 09:00 PM | Bright, soft, circular with broad bright core. Sits just east of a triangular asterism with an orange apex star. |
| M23 | OC | Easy | 16-Sep-07 | 09:50 PM | Beautiful, large, finely grained cluster. Bright star rests outside the northwest edge. Not concentrated. |
| M24 | SC+OC | Easy | 16-Sep-07 | 10:00 PM | Huge, sparkling cloud of stars. Oblong with many bright stars over a fine grained backdrop. |
| M25 | OC | Easy | 16-Sep-07 | 10:15 PM | Bright, irregular, nicely resolved with grainy background. Fairly condensed core. |
| M26 | OC | Challenge | 16-Sep-07 | 10:35 PM | Small , circular, not resolved except for 1 star on southwest portion of core. Appears moderately condensed. Forms east apex of right-triangle with 2 bright stars. |
| M27 | PN | Easy | 17-Sep-07 | 09:20 PM | Bright, circular. Two-lobed structure just barely visible. |
| M28 | GC | Tougher | 16-Sep-07 | 09:05 PM | Small, soft with strongly condensed core. |
| M29 | OC | Easy | 16-Sep-07 | 02:40 AM | Small, grainy and condensed. Same field as Sadr. |
| M30 | GC | Tougher | 17-Sep-07 | 10:00 PM | Small, moderately condensed. Paired with a star of similar magnitude just to its west side. Much brighter star lies a bit further to its east. |
| M31 | Gal | Easy | 16-Sep-07 | 01:40 AM | Beautiful, elongated. Northwest edge sharper. Super condensed core. |
| M32 | Gal | Challenge | 16-Sep-07 | 01:40 AM | Soft, small disc outside south edge of visible portion of M31. |
| M33 | Gal | Tougher | 16-Sep-07 | 02:05 AM | Soft, oval, with broad central condensation. Sits within diamond asterism. |
| M34 | OC | Easy | 16-Sep-07 | 02:50 AM | Sparse, fairly resolved. Lies at the heart of a rhombus asterism like a heart in a chest. |
| M35 | OC | Easy | 16-Sep-07 | 02:50 AM | Large, soft and grainy with about 10 brighter stars involved. Nice curving string of stars peels away to the south. |
| M36 | OC | Easy | 16-Sep-07 | 01:55 AM | Grainy, concentrated, shaped like an “A”. |
| M37 | OC | Easy | 16-Sep-07 | 01:55 AM | Soft, lumpy, concentrated. |
| M38 | OC | Easy | 16-Sep-07 | 01:55 AM | Grainy, irregular, loose. Sits just north of Cheshire Cat Asterism. |
| M39 | OC | Easy | 16-Sep-07 | 02:45 AM | Large, fully resolved, loose, about 2 dozen stars apparent. Crooked peace symbol shape. |
| M40 | Dbl | Tougher | 17-Sep-07 | 08:40 PM | Needed to memorize the star field carefully. It showed up northeast of 70 Umaj. Couldn't resolve into 2 stars though. |
| M41 | OC | Easy | 26-Jan-08 | 09:40 PM | Large (3 to 4 degrees) with bright well-resolved stars over a foam of fainter stars. X-shaped. Right central star appears yellow-orange. |
| M42 | OC+EN | Easy | 16-Sep-07 | 03:05 AM | Beautiful, bow/fan shape with loads of bright stars all around in linear sweep. |
| M43 | EN | - | 16-Sep-07 | 03:05 AM | Tough to distinguish from M42. Centered on bright star north of the trapezium. |
| M44 | OC | Easy | 26-Jan-08 | 10:20 PM | Huge with bright stars. About a dozen bright members with a couple dozen more faint members. Has an almost rectangular appearance. |
| M45 | OC | Easy | 16-Sep-07 | 01:50 AM | Brilliant, loose collection of bright blue stars. Wonderful streamer of stars hanging off. |
| M46 | OC | Easy | 26-Jan-08 | 09:55 PM | Very soft, round haze with a grain of about 8 stars emerging above the background. Beautiful pair with M47. About .5 degree in size. |
| M47 | OC | Easy | 26-Jan-08 | 09:55 PM | Appears fully resolved with a couple dozen stars. Elongated northeast to southwest and about .75 degree wide in that direction. |
| M48 | OC | Easy | 26-Jan-08 | 10:10 PM | Large, grainy with more than a couple dozen stars resolving. Elongated northwest to southeast. Great binocular OC. |
| M49 | Gal | Tougher | 30-Mar-08 | 11:00 PM | Soft, non-descript patch, nearly midway between 2 bright stars in the “back” of a lawn chair shaped asterism. |
| M50 | OC | Easy | 26-Jan-08 | 10:00 PM | Full range of resolution, soft, round haze with overlying grain and about 8 or so more distinct stars. Two brighter stars north and south give an oval appearance. |
| M51 | Gal | Challenge | 17-Sep-07 | 08:25 PM | Soft, moderately condensed, appears to be elongated...indicating detection of NGC 5195 in the combined light. |
| M52 | OC | Easy | 16-Sep-07 | 02:40 AM | Soft, round, mostly unresolved. One bright star superimposed. |
| M53 | GC | Tougher | 30-Mar-08 | 10:50 PM | Bright, round, with a broad, robust core. Situated between diadem and a rough streamer of stars. |
| M54 | GC | Challenge | 16-Sep-07 | 09:10 PM | Small, but strongly condensed core. |
| M55 | GC | Easy | 17-Sep-07 | 09:35 PM | Huge, bright, only slightly condensed. Circular. |
| M56 | GC | Challenge | 16-Sep-07 | 10:40 PM | Soft, moderately condensed. Possibly overlapping star makes it look like a double-core aligned northwest to southeast. |
| M57 | PN | - | 16-Sep-07 | 10:35 PM | Actually nicely visible. Almost stellar. Forms apex of a flat isosceles triangle of stars that is also connected to another triangle. |
| M58 | Gal | - | 02-Apr-08 | 09:35 PM | A bit difficult, just below a bright star. Somewhat condensed. |
| M59 | Gal | - | 02-Apr-08 | 09:20 PM | Difficult. Near M60. Just a soft patch of haze. |
| M60 | Gal | - | 02-Apr-08 | 09:20 PM | Rather easy. Soft patch. Good concentration at center. |
| M61 | Gal | - | 30-Mar-08 | 11:10 PM | Soft patch in a bright, starry field. |
| M62 | GC | Tougher | 17-Sep-07 | 08:55 PM | Tough sighting with moon in this part of the sky. Strongly condensed. |
| M63 | Gal | Tougher | 17-Sep-07 | 08:35 PM | Tough sighting in this part of the sky. Very subtle. Elongated 2:1. |
| M64 | Gal | Tougher | 30-Mar-08 | 10:50 PM | Slightly oval, soft with gradual brightness profile. Sits below the base of a wide isosceles triangle of stars. |
| M65 | Gal | Challenge | 30-Mar-08 | 10:35 PM | Relatively easy to spot. Round. Forms a right triangle with M66 and a bright star. |
| M66 | Gal | Challenge | 30-Mar-08 | 10:35 PM | Large and easy to see. Highly elongated with a bright core, situated between two bright stars and elongated in their direction. |
| M67 | OC | Easy | 26-Jan-08 | 10:20 PM | Soft ellipse aligned southwest to northeast. A hint of granularity, with 1 bright star on the northeast edge. |
| M68 | GC | Challenge | 02-Apr-08 | 09:05 PM | Soft, unresolved spot. Only slight condensation with averted vision. Easy to confuse with nearby group of stars. |
| M69 | GC | - | 16-Sep-07 | 09:15 PM | Small, faint, soft patch with a notable star just north of it. Mildly condensed. |
| M70 | GC | - | 16-Sep-07 | 09:20 PM | Soft, faint patch, mildly condensed. Rests north of two angled star groups. |
| M71 | GC | Challenge | 16-Sep-07 | 10:45 PM | Faint, soft, barely condensed. Wants to hide in the lumpy Milky Way. |
| M72 | GC | - | 17-Sep-07 | 09:50 PM | Very faint and small. Located next to a star in the lower left corner of a rhomboid asterism. |
| M73 | Ast | - | 17-Sep-07 | 09:55 PM | Faint, and nearly stellar. Part of a line of 3 other stars. |
| M74 | Gal | - | 16-Sep-07 | 03:25 AM | Extremely difficult. Midway from Eta PSC to star pair with a mag 10.5 star .25 degree to the east. Appears as a small, faint glow. |
| M75 | GC | Challenge | 17-Sep-07 | 09:45 PM | Small, faint, moderately condensed. |
| M76 | PN | - | 16-Sep-07 | 02:15 AM | Very difficult. Small, faint, soft patch .25 degree north of 6.6 mag star in Perseus. |
| M77 | Gal | - | 16-Sep-07 | 03:15 AM | Nearly 1 degree east-southeast of Delta CET. Small, soft, faint spot at end of star chain. |
| M78 | RN | Tougher | 16-Sep-07 | 03:00 AM | Small, soft patch at right angle with Orion belt stars. |
| M79 | GC | Tougher | 21-Sep-07 | 03:00 AM | Small, faint, fairly condensed. Notable companion star just to its south. |
| M80 | GC | Tougher | 17-Sep-07 | 08:15 PM | Small, moderately condensed. Sports a close neighbor star on its northeast side. First quarter moon 4 degrees away. Still showed up nicely. |
| M81 | Gal | Tougher | 16-Sep-07 | 03:30 AM | Soft, oval with condensed core, just south of M82 for great pair. Sits at north apex of triangle formed with 2 stars. |
| M82 | Gal | Tougher | 16-Sep-07 | 03:30 AM | Soft, highly elongated. Bright axis running along its core, but fainter than M81 to the south. |
| M83 | Gal | Tougher | 02-Apr-08 | 11:15 PM | Large! Softly circular, with mildly condensed core. |
| M84 | Gal | - | 02-Apr-08 | 10:45 PM | Fairly easy, right next to M86. Round and condensed. (NGC 4435 and 4438 combo also visible on other side of M86.) |
| M85 | Gal | - | 02-Apr-08 | 11:10 PM | Situated right next to a star of similar magnitude. The well-condensed core forms a “double” with that star. Circular. |
| M86 | Gal | - | 02-Apr-08 | 10:45 PM | An easy catch, fairly condensed and slightly elongated. Right next to M84 and NGC 4435/4438 on either side. |
| M87 | Gal | - | 02-Apr-08 | 10:40 PM | Fairly easy, large, well-condensed. |
| M88 | Gal | - | 02-Apr-08 | 10:30 PM | Not too difficult. Soft, relatively large. |
| M89 | Gal | - | 02-Apr-08 | 10:20 PM | Difficult. Almost stellar, but still soft with a well-condensed core. |
| M90 | Gal | - | 02-Apr-08 | 10:20 PM | Difficult, larger than M89, couldn't detect condensation. |
| M91 | Gal | - | 02-Apr-08 | 10:35 PM | Very difficult. I think only the core was showing. Looks like a faint star on the left corner of a triangle of other stars. |
| M92 | GC | Easy | 16-Sep-07 | 09:35 PM | Bright, soft, strongly condensed core. |
| M93 | OC | Easy | 26-Jan-08 | 09:45 PM | Soft elongated (east-west) glow with 4 or 5 stars starting to resolve out of the mist. |
| M94 | Gal | Tougher | 02-Feb-08 | 11:25 PM | Bright. Round and sharply condensed. |
| M95 | Gal | - | 30-Mar-08 | 10:25 PM | Very difficult. Forms shorter edge of right triangle with M96 and a brighter star. It also sits just east of another faint star. |
| M96 | Gal | - | 02-Feb-08 | 11:35 PM | Soft, formless patch. |
| M97 | PN | Challenge | 02-Feb-08 | 10:55 PM | Not easy, but much easier than nearby M108. A faint soft star-like object. |
| M98 | Gal | - | 02-Apr-08 | 11:00 PM | Pretty difficult. Elongated and no condensation that I could see. |
| M99 | Gal | - | 02-Apr-08 | 10:55 PM | Fairly easy, round, moderately condensed. |
| M100 | Gal | - | 02-Apr-08 | 10:55 PM | Fairly easy, round, larger than M99 and moderately condensed. |
| M101 | Gal | Challenge | 17-Sep-07 | 08:45 PM | Large! Very softly defined. Slightest hint of condensation and elongated northeast-southwest slightly. |
| M102 | Gal | - | 17-Sep-07 | 09:30 PM | Required lots of effort. Very small. Moderately condensed. Needed to compare closely to star field. |
| M103 | OC | Easy | 16-Sep-07 | 02:35 AM | Linear shape, grainy, three prominent linear stars. North star brightest. |
| M104 | Gal | Challenge | 02-Apr-08 | 09:10 PM | Fairly straightforward to see near a couple nice binocular doubles. Is easy to see elongation pointing toward brighter double. |
| M105 | Gal | - | 30-Mar-08 | 10:10 PM | Almost stellar, with slight diffuseness. Forms right triangle with 2 nearby stars. Ended up spotting NGC 3384 right next to it! |
| M106 | Gal | Challenge | 02-Feb-08 | 11:20 PM | Relatively easy. Elongated and brighter towards the middle. Rests along one edge of right triangle of stars. |
| M107 | GC | - | 17-Sep-07 | 09:10 PM | Extremely difficult with light pollution and low altitude. Appeared as slightest sky brightening with no detail to see at all. |
| M108 | Gal | - | 02-Feb-08 | 11:00 PM | Very difficult and intermittent. But at right position at end of an arc of stars. Very soft, but elongated. |
| M109 | Gal | - | 02-Feb-08 | 11:15 PM | Very difficult. Right next to a 9th magnitude star. Appears as a soft glow hanging off this star. |
| M110 | Gal | - | 16-Sep-07 | 01:40 AM | Very faint patch brightening sky northwest of M31 and perpendicular to M31's axis. |
Posted by Jeremy at 10:26 PM
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April 3, 2008
Saturn, The Deep Sky and My Daughter
Last Sunday night, my daughter asked if we could bring out the telescope and do some stargazing. Boy was that the kick in the caboose I needed! (As you can see by the M64 sketch I managed later that night.) As I brought the Dob out the front door, I noticed that she had her clipboard, paper and pencil ready: "I wanna sketch something..." she said as I crouched to keep the scope from banging into the door frame.
So awesome!
We started with Saturn, and I suggested that she try to draw the position of the moons so that we could check and see which ones she spotted. She saw Titan right away, and with a little more time, and urging from Dad, she picked up Rhea and Tethys too. After she finished her sketch, I had a look and grabbed a quick sketch myself--she made sure to complete my drawing with a sketch circle =D
Move mouse over sketch above to view labels.
Next we had a look at M35 and she insisted on trying to sketch it. I let her have a go at it, but she got lost in all the stars so we moved right along for a quick look at Mizar and Alcor, and then on to a couple bright galaxies.
M81 and M82 were nicely placed in the sky, and after discussing what she was seeing, she got busy with the drawing. We didn't have any other sketching supplies with us, so she used the pencil eraser to fuzz the galaxies up a bit, and that seemed to do the trick!
Move mouse over sketch above to view labels.
The air got chillier, and it was a school night, so we went inside and pulled up some photos of the galaxies she had just sketched. By that time, my son joined us, and we oohed & ahhed at some of the great shots Google brought up while discussing what was going on in those distant galaxies. My son was struck by the thought that near-collisions between them is what got M82 all stirred up and crazy looking. --speaking of 'looking'-- I'm looking forward to the warmer nights, and doing that together some more as summer approaches.
Posted by Jeremy at 2:02 AM
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March 31, 2008
M64
Click image for larger version.
Observation Notes:
Home is not the best place to soak in galactic light, but I've got to take what I can get! After scooping up a variety of galaxies with my 15 x 70 binoculars, I decided to take a closer look at M64 with the 8-inch Dob. The galaxy was elongated from east to west, with a core that was bright and appeared stellar. It dropped sharply in brightness on the north side of the core, suggesting a dust band. The galaxy appeared brightest across the southwest quadrant. The northern outer perimeter also had a sharper boundary.
Object Information:
This fascinating galaxy is well know for it's prominent dust lane that has earned it the name "Blackeye Galaxy". The galaxy has two counter-rotating discs of gas, dust and stars. It may be the reason vigorous star formation is observed and noticeable in the dust lane. It is also thought that this condition was caused by a former companion galaxy that has merged with, but not yet settled into the orbital plane. It's distance is not well determined, and has been estimated from 16 to 44 million light years. A recent press release from the Space Telescope Science Institute gives a value of 19 million light years. At this distance, the galaxy's diameter would be 51,000 light years. M64 was discovered by Edward Pigott in 1779. It is also catalogued as NGC 4826, UGC 8062, MCG+04-31-001, h 1486, GC 3321,CGCG 130.001, KARA 559, IRAS 12542+2157, PGC 44182.
| Subject | M64 / NGC 4826 |
| Classification | Spiral Galaxy (Sb) |
| Position | Coma Berenices [RA: 12:56:44.2 / Dec: +21:40:58]* |
| Size* | 10' x 5.4' |
| Brightness* | 8.4 vMag / 9.1 bMag |
| Date/Time | September 13, 2007 - 11:30 PM MST (September 14, 2007 - 06:30 UT) |
| Observing Loc. | Flagstaff, AZ - Home |
| Instrument | Orion SkyQuest XT8 (203 mm dia./1200 mm F/L) |
| Eyepieces/Mag. | 10 mm Sirius Plössl (120X) |
| Conditions | Mostly Clear, breezy |
| Seeing | 4/10 Pickering |
| Transparency | ~ Mag 5.8 NELM |
| *References | NGC/IC Project; SEDS |
Posted by Jeremy at 3:12 AM
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March 25, 2008
Alpha Geminorum (Castor / Struve 1110)
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 companion hinted at a subtle blue.
Measuring this duo using the Dobsonian scope was very challenging. I was attempting the PA measurement without my external dial, and although it was very tough to get the primary to drift through the exact center of the eyepiece, the measurement worked out fairly well--differing from Workman's calculated 2008.2 value by only .8 degrees. The separation estimate was worse though, since I couldn't track and allow the stars to hover over the scale. (My estimate of 6.9 arc seconds was a bit over compared to the calculated value of 4.5 arc seconds).
| Subject | Alpha Geminorum (Castor / STF 1110) |
| Classification | Multiple Star |
| Position (J2000) | Gemini [RA: 07:34:35.7 / Dec: +31:53:16]* |
| Position Angle* | 59° [2008.2 my measurement]
58.2° [2008.2 Brian Workman's DS Calculator] |
| Separation* | 6.9" [2008.2 my measurement]
4.5" [2008.2 Brian Workman's DS Calculator] |
| Magnitudes* | 2.0 / 2.9 |
| Spectral Types* | A1V / A2Vm |
| Date/Time | MAR 19, 2008 - 10:45 PM MST (MAR 20, 2008 - 05:45 UT) |
| Observing Loc. | Phoenix, AZ |
| Instrument | Orion XT8 (203 mm dia./1200 mm F/L) |
| Eyepieces/Mag. | 10 mm Sirius Plössl + 2X Barlow (240X)
12 mm Meade Astrometric EP + 2X Barlow (200X) |
| Conditions | Mostly Clear, Gibbous Moon |
| Seeing | 3-4/10 Pickering |
| Transparency | NELM Mag ~4.0 |
| *References | The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996); Starry Night Pro Plus 5.8 |
Posted by Jeremy at 12:12 AM
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