Astronomical Observations: 13 July 2011

Observing Location

TotL

Observational Period

1600-1700 EDT

Atmospheric Conditions

Cloud Cover	Clear
Temperature	84° F
Wind	Gentle Breeze
Wind Chill Effect Heat Index	84° F
Humidity	46%
Barometric Pressure	29.73" Hg 7
KNYC METAR	131951Z AUTO 26007KT 220V300 10SM SCT055 29/16 A2975 RMK AO2 SLP065 T02890161 TSNO
Feels Like	very hot

Transparency	Excellent
Seeing	I

Instruments

Celestron 70mm Mini Mak - Charlie

Celestron 25x-75x zoom eyepiece (stock with the Mini Mak)
Kendrick #6004 filter cell with Baader Astro Solar visual filter film
FAR Laboratories Helio-Pod finder
Empire Magnetic POLYCAST Protractor

Observing Party

Charlie Ridgway

Session Objectives	to finally get the Sun into the eyepiece of the Mini Mak - achieved, to figure out where the Sun's image should be on the Helio-Pod when it is in the eyepiece - achieved, to perform a sunspot count - achieved, and to observe the ISS with Shuttle attached pass across the disk of the Sun - not observed.

I used Sly Safari v2.1.2 to determine the altitude of the sun which I set on my protractor. I held the protractor on top of the scope barrel and aligned the plumb bob with the appropriate index mark. The sun wasn't there when I swung the scope across the sky but at one point there was a flash of light on the bottom edge of the mirror so I scanned down at that location until I found the sun.

The scope is going to be good for what I got it for, grab-and-go solar observing. At 25x the view was crisp and easy to focus. I saw all the major spots although one of then I interpreted as one spot when it resolved into two at 50x. The view is a little softer at 50x but still good enough to resolve additional detail. 75x is nearly worthless. It is soft and hard to achieve critical focus.

I had the Helio-Pod mounted on the left side of the scope near the eyepiece and found that when the Sun was centered in the eyepiece its image was offset high and to the left on the bulseye but just outside of the central target. I could reliably get the Sun into the eyepiece using the Helio-Pod knowing this.

Target

Sunspots

Constellation

Gem

Category

Solar

Time
yyyymmdd.hhmm

20110713.1610 EDT

Distance Light Time	1.02 AU 8^m 27^s
Angular Size	31' 31.1"
Altitude	46° 18'
Heliographic Latitude (B₀)	4.17°
Heliographic Longitude (L₀)	216.60°
Parallactic Angle (P)	2.93°
Carrington rotation number (CR)	2112

Comments

At low power I saw Group 2050 in the SE quadrant composed of three spots and Group 2051 in the NE quadrant composed of a single spot. At medium power the easternmost trailing spot of group 2050 resolved into two smaller spots.