Additional scales used for observations
Seeing
1 - Turbulent, unsteady
2 - Few moments of stability, higher power useless
3 - Average
4 - Above average, high power tolerated well
5 - Exceptional seeing permitting power 50x objective
Transparency
1 - Hazy or foggy, only brightest stars visible
2 - Thin clouds, losing at least 1-2 magnitudes
3 - Average
4 - Above average with slight gain in limiting magnitude. Blinding sunset.
5 - Exceptional, gain of nearly a full magnitude over average night.
Saturday, January 13, 2007
Object Rating Scale
Rating of objects is a sum of these attributes
Targeting
How easily can you locate the object?
0 No significant nearby guide stars, only chance is by sweeping areas. Over 10 minutes to find.
1 Several degrees from bright stars but fainter stars in finder can guide. Found in under 10 minutes.
2 Bright stars in area to triangulate from. Found in 1-2 minutes.
3 Near bright star or directly visible. Found in less than a minute.
Visibility
How easy is the object to see - its brightness
0 Object needs confirmation by star chart
1 Subtle, needs averted vision
2 Visible but enhanced by averted vision
3 No averted vision really needed
Wow Factor
Subjective impression on the observer
0 Is there something there?
1 Object is distinct from the field stars
2 Object is above average and one you'll want to revisit
3 A memorable classic that you frequent
Interest
Does the object have some background history of interest
0 No realy historical or scientific background to the object
1 Object has historical or scientific significance
Maximum Score: 10
Targeting
How easily can you locate the object?
0 No significant nearby guide stars, only chance is by sweeping areas. Over 10 minutes to find.
1 Several degrees from bright stars but fainter stars in finder can guide. Found in under 10 minutes.
2 Bright stars in area to triangulate from. Found in 1-2 minutes.
3 Near bright star or directly visible. Found in less than a minute.
Visibility
How easy is the object to see - its brightness
0 Object needs confirmation by star chart
1 Subtle, needs averted vision
2 Visible but enhanced by averted vision
3 No averted vision really needed
Wow Factor
Subjective impression on the observer
0 Is there something there?
1 Object is distinct from the field stars
2 Object is above average and one you'll want to revisit
3 A memorable classic that you frequent
Interest
Does the object have some background history of interest
0 No realy historical or scientific background to the object
1 Object has historical or scientific significance
Maximum Score: 10
Sunday, January 7, 2007
Eta Cassiopeia
Object: Eta Cassiopeia
Constellation: Cas
Type: Double Star
Date and Time: Jan 6, 2007 00:30 UT
Conditions: Partly cloudy, 60°, light winds
Instrumentation: 60mm refractor, 10mm (80x)
Rating
Targeting: 3
Visibility: 2
Wow: 0
Interest: 1
Total rating: 6
Comments: This double is easy to locate near Alpha Cassiopeiae and is fairly obvious as a double at 80x. The secondary is a good deal fainter (7.5) and colorless compared to the significantly brighter primary (3.4) which appears to have a bit of a yellowish – orange tone. PA guesstimate was 330°, actual is 307°. Sparse field stars accompany it. This primary is apparently pretty similar to Sol and so offers you the perspective of what our own star would look like ~19 light years away.
Sketch:
Genesis
Those of you who subscribe to the Delmarva StarGazers Yahoo group are aware of Don’s challenge to rekindle some of the passion that most of us have for this crazy hobby. To one degree or another we all succumb to other obligations and distractions that reduce our astronomy activity to little more than occasionally visiting APOD or spending 15 minutes skimming Sky and Telescope or Astronomy. And then there’s the issue of venues – many suburban members face the combination of a limiting skyline and abundant sky glow on the home front that quickly infuse one with a sense of futility in setting up a telescope. Yes, countering the influences and carving out that time at the eyepieces will likely be a bit of a battle.
Step one for me is to join the DSG even though I’ll likely be in absentia at meetings given my Baltimore County residence. But really my attendance does not matter much given that electronic communication today allows me to be a “virtual” member, plus I’ll hopefully still rub elbows with the membership at Tuckahoe occasionally.
Second, I’m going to need some focus for the observing in order for it to be satisfying. Don’t get me wrong, there’s immense pleasure in just kicking back and soaking in the grandeur of the night sky in an unstructured approach – just not from my backyard. From attempting to accurately time the transit of a Jovian feature to bagging another faint fuzzy from the Herschel list, purpose serves as catalyst for getting out there. Pragmatism will also be important to reclaiming an active observing status. If the prospect of wrestling the 10” to the porch and awaiting it to cool on a winter’s evening is too off-setting then the 7 x 50 binoculars for a short 20 minute sortie will serve the purpose.
So what will this series be about? For the moment the project that captures my imagination is revisiting the AL’s Urban List and assessing it. A few years ago at a yard sale to raise funds for my sons’ scout troop there was a 60mm refractor for sale. Not a typical Tasco fiasco, but one with a surprisingly nice GEM. So when there were no takers I acquired it for $15 (the hard part was convincing my better half that I needed yet another, smaller scope to add to the stable). I upgraded the two eyepieces and tacked on a red-spot finder to make it more functional, and it resides covered on the porch, ready to go at a moment’s notice. So my question is just how realistic is the Urban list for a 60mm refractor in limiting magnitude 4 skies? What may have been overlooked from the list – and what should have never made the cut?
Step one for me is to join the DSG even though I’ll likely be in absentia at meetings given my Baltimore County residence. But really my attendance does not matter much given that electronic communication today allows me to be a “virtual” member, plus I’ll hopefully still rub elbows with the membership at Tuckahoe occasionally.
Second, I’m going to need some focus for the observing in order for it to be satisfying. Don’t get me wrong, there’s immense pleasure in just kicking back and soaking in the grandeur of the night sky in an unstructured approach – just not from my backyard. From attempting to accurately time the transit of a Jovian feature to bagging another faint fuzzy from the Herschel list, purpose serves as catalyst for getting out there. Pragmatism will also be important to reclaiming an active observing status. If the prospect of wrestling the 10” to the porch and awaiting it to cool on a winter’s evening is too off-setting then the 7 x 50 binoculars for a short 20 minute sortie will serve the purpose.
So what will this series be about? For the moment the project that captures my imagination is revisiting the AL’s Urban List and assessing it. A few years ago at a yard sale to raise funds for my sons’ scout troop there was a 60mm refractor for sale. Not a typical Tasco fiasco, but one with a surprisingly nice GEM. So when there were no takers I acquired it for $15 (the hard part was convincing my better half that I needed yet another, smaller scope to add to the stable). I upgraded the two eyepieces and tacked on a red-spot finder to make it more functional, and it resides covered on the porch, ready to go at a moment’s notice. So my question is just how realistic is the Urban list for a 60mm refractor in limiting magnitude 4 skies? What may have been overlooked from the list – and what should have never made the cut?
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