33 Doubles Observing Projects: Otto Struve 417

Otto Struve 417

Dave Jenkins				dave.jenkins@arkona.com
Star: Otto Struve 417 Date & Time: 8 July, 2004 Seeing: 6 <1-10 Seeing Scale (10 best)>. Transparency: 3 out of 4 Location of site: Orem, Utah Lat. 40.28 Long. 111.70 Site classification: Bright Suburban Sky darkness: <Limiting magnitude> Telescope: C11, TV85 Eyepieces: 7mm Magnification: 400x				I’m surprised. This double was not cleanly split but I was able to see to distinct whitish balls. Used an inexpensive GTO 7-21mm zoom set at 7. This is a handy little eyepiece for double star work.

Steve Bodin				sdbodin@hotmail.com
Star: Otto Struve 417 Date & Time: 26 July 2004, 11 pm to 1 am local Seeing: 6-7 <1-10 Seeing Scale (10 best)>. Transparency: poor Location of site: Silverdale WA, USA 47N 123W Site classification: suburb-rural Conditions: temp 60F, dry Sky darkness: 4.5 <Limiting magnitude> Telescope: Celestron C8 Eyepieces: not used Additional: DX-8263SL video camera at 3x Magnification: app. 1000x				A bit fainter and more difficult than 16 Vul. Both stars a blue-white color and nearly equal in brightness. There is a fainter third component to the east, but not seen this time. Measurement: 0.98 sec at 028.8 deg PA.

Morgan Spangle				msfainc@earthlink.net
Star: Otto Struve 417 Date & Time: 29 July 2004; 3 August 2004 Seeing: 8 <1-10 Seeing Scale (10 best)> Transparency: 4-6 <1-10 Scale (10 best)> Location of site: `Purchase, New York` Site classification: Bright Suburban Sky darkness: <Limiting magnitude> `Conditions:` 75 degrees F, falling, dewy Telescope: `Borg 101ED refractor Mount: VixenGP-DX mount, Sky Sensor 2000PC, Palmdevice running Planetarium software` Eyepieces: `Takahashi Orthos: 18mm, 9mm, 5mm, 2.8mm, mounted in a Borg turret eyepiece holder` Magnification: 35x, 71x, 128x, 228x				super dim wide pair, best at 128x for contrast

Ilario Melandri

morinipa@PAOLOMORINI.191.it

Star: Otto Struve 417
Date & Time: 29/07/2004
20:00-24:00 UT
Seeing: 7<1-10 Seeing Scale (10 best)>
Transparency: ---
Location of Site: S. Romualdo, Ravenna, Italy
Site classification: Rural
Temperature: around 19ºC
Sky darkness: -- <Limiting magnitude>
Telescope: 150mm f/15 refractor
Eyepieces: 16mm and 6mm Plossl, 9mm ortho
Magnification: 140x, 250x, 375x

The kind of double to stress the “power” of refractors.

Bob Hogeveen				bob.hogeveen@hetnet.nl
Star: Otto Struve 417 Date & Time: 3 August 2004, 23.00 pm to 00.30 am LT Seeing: 8-9 <1-10 Seeing Scale (10 best)> Transparency: <1-10 Scale (10 best)> Location of site: Site classification: Village-backyard Sky darkness: 4 <Limiting magnitude> `Conditions:` bright moon low in the southeast Telescope: Celestron C11 Eyepieces: Pentax SMC XL 40mm, TV plossl 20mm, China plossl 10mm Magnification: 70x, 140x, 280x				With a separation of 0.9" and almost equal brightness of the components, not too bright, not too faint, this is an easy "nutcracker" for the C11. At 280x the split is wide and easy (wide means here: almost the same size as the starimages...). Only for short moments the image is spoiled by lesser seeing. Rating 3 on the Harshawscale (1-5, 1 best)