Schudel Family - Astronomy Log

• Who: Daniel, Abigail, Bennetts, Meldrums, Sousas
• Time: 20:30 EDT
• Temperature: 80 degrees F
• Location: Medoc Mountain State Park - Group Campsite Field
• Equipment: Astroscan with 21.5mm RKE
• Viewing Plans
  • Venus, M44, Saturn, Cor Caroli (Alpha Canum Venaticorum), M81/M82, M3, Mizar/Alcor, Polaris
  • Previously Seen - M3, M44, M51, M94
  • Comet C/2009 R1 (McNaught)
  • Stellar - SS Virginis, Iota Cancri, Mizar/Alcor, Polaris, Gamma Leonis, Cor Caroli (Alpha Canum Venaticorum)
  • Easy - M3, M5, M51, M64, M83, M101, M104
  • Difficult - M63, M84, M86, M87, M102, M106,  NGC4449, NGC4565, Mel 111, NGC 5566, NGC 5585, NGC 5689, NGC 5746, NGC 5813, NGC 5838, NGC 5907
• Viewing Results
  • Venus, Saturn, Acturus, Cor Caroli, M13, M3
  • Seeing conditions were quite poor.  There was a large amount of dew and condensation.  A very bright light on the group campsite bathhouse bathed the entire field in light.  A way to temporarily shield this light is needed for next time.

• Who: Daniel, Allen D., Mark S.
• Time: 22:30 EDT
• Temperature: 80 degrees F
• Location: Medoc Mountain State Park - Five Acre Field
• Equipment: Allen's 20" f/5 Obsession
• Viewing Results
  • Very impressive!
  • M57 - Ring Nebula
  • NGC 6543 - Cats Eye - I could see the central star
  • M20 - Triffid Nebula
  • M8 - Lagoon Nebula
  • Veil Nebula (NGC6960, 6992, 6995) with an OIII filter - was very impressive and very large.  52 Cygni, near NGC6960, was an electric blue due to the OIII filter.
  • Flashing Nebula - can't find any references to this name
  • A few globulars that I lost track of

• Who: Daniel, Vickie, Abigail, Adah, and the Krebs Family
• Time: 20:30 EDT
• Temperature: 80 degrees F
• Location: Krebs'
• Equipment: Astroscan with 21.5mm RKE
• Viewing Plans
  
  • Sky view - star clusters on / off
  • Venus, M44, Saturn, Cor Caroli (Alpha Canum Venaticorum), M81/M82, M3, Mizar/Alcor, Polaris
  • Previously Seen - M3, M44, M51, M94
    
  • New and Reasonable - M53, M64, M83, M104, NGC 3242
    
  • New and Challenging - M63, M65, M66, M84, M86, M87, M95, M96, M97, M105, M106, M108, M109, NGC 3115, NGC 3628, NGC 4449, NGC 4565
  • Stellar - SS Virginis, Iota Cancri, Mizar/Alcor, Polaris, Gamma Leonis, Cor Caroli (Alpha Canum Venaticorum)
• Viewed
  • Venus

Definitions

• Lights - Frames that include the subject matter.
  
• Offset/Bias frame - A calibration image taken with little to no exposure time.  Corrects for the noise inherent in the CCD.  Can be taken anytime and are considered viable for long periods of time.
  
• Dark frame - A calibration image taken with the same exposure time as the "Lights" frames.  Corrects for thermal and electro-luminescent noise that accumulates over long exposures.  Should be taken near to the same time as the lights so that temperature conditions are nearly identical.
• Flat frame - A calibration image taken of a uniformly bright, white screen.  Corrects for optical problems with the CCD and telescope.  Note that the focus point used on the subject must used when taking the flat frame.
• Cosmetic file - A file specific to IRIS that identifies hot, or warm, pixels on the CCD.  Derived from the dark frame.
  

Hints

• Take several (7-9) exposures of each of the calibration frames.  Then use IRIS to combine them.
• 2:1- lights to darks

GUI Procedures for IRIS

• Preprocssing->"Make an offset..." - Save the resulting master offset image.
  
• Preprocssing->"Make a dark..." - Save the resulting master dark image.
  
• Preprocssing->"Make a flat-field..." - Save the resulting master flat-field image.
• Load the master dark image and run "find_hot cosm X".  Vary X until 100-200 hot pixels are identified.  Result is in cosm.lst.
• Preprocessing->"Automatic preprocessing(1)..." or Preprocessing->"Automatic preprocessing(2)..."

CLI Procedures for IRIS

The above has been adapted from http://astro.ai-software.com/articles/dslr_iris/dslr_iris.html and http://www.saratogaskies.com/articles/cookbook/index.html

• Who: Daniel, Vickie, and Dad
• Time: 21:00 EDT
• Temperature: ~55 degrees F
• Location: Leeward Court
• Equipment: Astroscan with 21.5mm RKE
• Viewed
  
  • Mars
• Notes
  • We just sneaked a peak at Mars before the clouds took over

Info

• NGC4567 and NGC4568
• Siamese Twins or the Butterfly Galaxies

Original Imaging Info

• Images captured with the 0.81 meter telescope at TCO by Dr. Danford at 2010-04-16 at 02:30:37 (UT)
• 1024x1024 Apogee CCD
• Three 200 second exposures with "zip 5" filter

Image Post Processing - Method 2

• I used IRIS v5.58 to align/register the three images. It appears the RA/DEC was shifted slightly for each image.  This shift is apparent in "Method 1" as the true stars are slightly elongated.
• The three images were stacked with "add_mean".
• A crop was applied to remove the artificial border introduced by the registration.
• Then "skypoint/poly 3/synthe" to identify the circular gradient surrounding the two galaxies.
• The resulting gradient was removed from the image stack with "sub sky 500".
• The intensity levels were adjusted to be logarithmic and the result was exported with "saveppm".
• The exported Netpbm/PPM image was imported into GIMP.
• I further adjusted the black/white levels to contrast the galaxies against the background. 
• Then an aggressive removal of lone "hot-pixels".
• Followed by an aggressive application of the "Destripe" filter to remove the horizontal stripes.

Click image for a larger view.

Image Post Processing - Method 1

• I used IRIS v5.58 to stack the three images using the "add_mean" command. 
• Then "Remove Gradient (Polynomial Fit)" with medium/medium parameters.
• The resulting sky was removed from the image stack with "sub sky 500".
• The final FITS image was imported into GIMP where I adjusted the black/white levels to contrast the galaxies against the background.  Then removed lone "hot-pixels".

Click image for a larger view.

Ideas For Improvement

• The white speckles appear to be stuck pixels in the CCD.  There are also, less noticeably, stuck black pixels.  A light image, and a dark image, should identify the culprits and allow them to be removed prior to registration.  This may also help in removing the gradient.
• The horizontal stripes could further be eliminated with more images that vary the RA/DEC.

Here is a digital sky survey image of a slightly larger area.

Info

• Saturn

Original Imaging Info

• Images captured with the 0.81 meter telescope at TCO by Dr. Danford on 2010-04-17 at 03:34:33 (UT)
• 1024x1024 Apogee CCD
• Three 1/2 second exposures with "zip 5" filter

Image Post Processing

• I used IRIS v5.58 to stack the three images using the "add_mean" command. 
• The final FITS image was imported into GIMP where I adjusted the black/white levels and used the "Unsharp Mask" filter.

Info

• Who: Daniel
• Session Moderator: Dr. Steve Danford of UNCG
• Time: 20:30 EDT
• Location: TCO
• Equipment: TCO - 32 inch f/13.5 reflector
• Sky View: Cluster PDF / Galaxy PDF (created with XEphem)

Would Like To See

• Leo Triplet - M65, M66, NGC3628
• Owl Nebula M97, and M108
• Barred spiral galaxy M109
• Planetary nebula NGC3242
• Edge-on galaxy NGC3628
• Eskimo Nebula NGC2392
• NGC4565
• M81 and M82
• M51

Visual Observing

• Castor - Visual binary star system.  Castor is actually a quadruple star system.
• Mars - Very difficult to make out any detail of the disk.
• NGC2392 - Clown Face/Eskimo Nebula - I could see the structure of the concentric layers of this nebula.
• Saturn - Very beautiful - with faint spears of rings on either side.  The shadow of the rings was noticeable.
• M82 - I was able to see and discern the dust lanes.
• M81 - I was unable to make out any spiral structure - but did recognize the component of the galaxy outside of the galaxy core.
• Two satellites - at 22:36 localtime, two satellites passed overhead, one following the other and slightly offset.  The dimmest was "Cosmos 2360 Rocket".  The other was very bright at first, then dropped sharply in magnitude.  At its brightest - it rivaled Venus.  This second object remains unidentified.
• M3 - Absolutely stunning.  The cluster occupied about 75% of the eyepiece FOV.  Hundreds of individual stars were discernible.  What was also amazing was seeing the "ripple" and "wave" motion of the atmosphere and how it affected the view of this cluster.
• Vesta - Actually viewed through the Astroscan.  Vesta has dropped off in magnitude noticeably since I started tracking it.

CCD Work

• Gamma Leonis - The binary star system was used to adjust the focus of the telescope.
• Saturn - Dr. Danford snapped hundreds of images of Saturn in an attempt to capture one at a point with cooperative atmosphere.  The photos were for a student that was studying the motions of Saturn's moons.

Notes

• I arrived at 20:20 for the 20:30 observing session.  The observatory was already packed full, with about 12 people still after me.  Early arrival is not necessary because everyone does get a chance to view every object.
• The strategy I used that worked well was to be the last person to view an object - then go outside and view through my scope.  I then reenter when the remaining line is short for the next object.

• Who: Daniel
• Time: 21:30 EDT
• Temperature: ~64 degrees F
• Location: Farrington Boat Ramp - western ramp
• Equipment: Astroscan with 21.5mm RKE
• Viewed
  • M44 - Beehive: Mediocre early in the night - better around 22:00.
  • Saturn
  • Vesta: It was possible to view Vesta and Algenubi (Epsilon Leonis) in the same FOV.
  • M67
  • M81 and M82: Viewing of the pair seemed to be better than 2010/03/19 session.
  • M51
  • M94
  • Cor Caroli (Alpha Canum Venaticorum): I could easily split the two stars.  The magnitude difference was very apparent.
  • M3: Very beautiful with a radial symmetry.  There was a well-defined center with a graceful drop of density/intensity.
• Notes
  • Robert N. and Jon S.T. from CHAOS were observing also.
  • Light from vehicles made observing tonight very tough and frustrating.  The warm night, and holiday weekend, brought out a lot of boat ramp traffic.

• Who: Daniel, Abigail, and Vickie
• Time: 20:00 EDT
• Temperature: ~66 degrees F
• Location: Leeward Court
• Equipment: Astroscan with 21.5mm RKE
• Viewed
  • Betelgeuse
  • Mars
  • M45 - Pleiades: The moon was passing very near to M45.  The cluster and the moon were all visible in the same FOV.  Clouds that rolled in prevented viewing an occultation.
  • M42 - Orion Nebula
• Notes
  • Abigail recognized the color similarity between Betelgeuse and Mars.

• Who: Daniel
• Time: 21:30 EDT
• Temperature: ~50 degrees F
• Location: Farrington Boat Ramp - eastern ramp
• Equipment: Astroscan with 21.5mm RKE
• Viewed
  • M37: Very blue - could discern one non-blue (perhaps orange) star in the center.
  • M38: About a dozen of the brightest stars are visible with faint blue around it.
  • M36: More compact than M38.
  • NGC2392: Did not find.
  • M35: Scattered, wide, low density.
  • M44 - Beehive: Impressive - as always.
  • Saturn: The rings were just visible - appearing as tiny spikes on opposite side of Saturn.  There is a lot of glare/flare emanating from the planet itself.  This could be the RKE or the AstroScan - I need to try other eyepieces to figure it out.  There were two moons to the left with the brightest the furthest out.  Virgo 10, on the right, was aligned and could have been mistaken for a moon.
  • Vesta: 23:31 localtime: In the FOV were about 7 bright objects.  Correlating this with XEphem puts the star limiting magnitude around 10.  Use "Stars Lim Mag" = 10 and "Mag Dot Step" = 1.
  • M81: This was the larger, brighter, fuzzier of the pair.  Both seemed to be washed out due to city lights to the north.
  • M82: Thin streak.  The pair were about a 1/2 FOV apart.
  • M51: Extremely dim and faint.  This is about at the limit for this scope.
• Notes
  • Kumar P. was observing also.
  • Viewed M44 in the AstroScan using a 22m Vixen Lanthanum Wide LVW Eyepiece (borrowed from Kumar).  The field of view was effectively wider due to significantly less distortion away from the center.