Sangamon Astronomical Society

Beta Lyrae

Where is Beta Lyrae in the sky?

• On summer evenings, the bright star Vega shines nearly overhead. (It the fall, Vega lies high in the northwest.) It is the primary star of the small constellation Lyra. (It is also 0.75º wnw of M57, the Ring Nebula.)
• Stretching from Vega's southeast are four dim stars in the shape of a parallelogram.
• Beta Lyrae is the star at the parallelogram's southwest vertex.

Your Observing Project

• Viewing through binoculars helps greatly.
• Closely examine the brightness of Beta Lyrae each night for up to two weeks. Try not to miss a night. (Yes, weather is always a problem!)
• Determine its estimated magnitude by interpolating the stated magnitudes for Delta, Gamma, and Zeta.
• Construct a graph showing the brightness of Beta over the two week period.

What you are seeing

• Beta Lyrae A consists of two stars, A1 & A2, of unequal brightness and size. They are so tightly separated that a telescope can not split them.
• When the dimmer but larger star, A2, is off to either side of the brighter, A1, the system appears at its maximum brightness of 3.4 magnitude. (Positions 1, 3)
• As the dimmer star orbits in front of the brighter, their total magnitude drops to the deep minimum, because the dimmer star is partially blocking the brighter one. (2)
• Again, when the dimmer star is off to the other side, the system is at maximum brightness. (3)
• When the dimmer star passes behind the brighter one, it is partially blocked causing the system's brightness to reach its secondary (shallow) minimum at 4.3 magnitude. (Position 4)

ALPO Webinar Demystifying Wavelets This webinar explains what wavelets are and how they sharpen planet...

The other night, I (Jeff Bryant) took a 1 hour exposure of a small area of the constellation Draco to see if I could get a set of 3 galaxies known as the Draco Trio (NGC 5982, NGC 5981 and NGC 5985). These are the bright galaxies near center of the annotated version of my original image shown. But upon close examination of the picture there are a bunch of little smudges in the background that are far more obscure and faint galaxies. Some of these are magnitude 18 (that's really faint)! And I picked them up from my backyard in southwest Champaign with my Seestar S50 with a 1 hour exposure! These galaxies are mostly in a more obscure galaxy catalog called the PGC catalog (Principle Galaxy Catalog).

Mark your calendars now for NCRAL 2027, next year's regional "event of the year" hosted by the Milwaukee Astronomical Society.

Circumpolar Stars
Some stars never set, others never rise

Stars between the celestial equator and the Zenith are above the horizon for more than 12 hours.
Stars on the celestial equator are above the horizon for 12 hours.
Stars between the celestial equator and the declination at geographic south are above the horizon for less than 12 hours.
Stars farther south than "90º minus your latitude" are circumpolar south and never rise.

Declination of the zenith equals your latitude

Stars farther north than your latitude (i.e., zenith declination) are circumpolar north and never set.

Polaris' altitude in degrees equals your latitude

Binocular Double Star Observing Program

https://www.astroleague.org/binocular-double-star-observing-program/

Effective Binocular Observing ...
Binoculars must be precisely focused.
Binoculars must be held steady. Mounted on a tripod is best.
Adequate dark adaption is needed. Wait at least 15 minutes in the dark before meaningful observing begins. 30 minutes is better.
Glare from a bright primary interferes with spotting a dim secondary. The greater the magnitude difference, the greater the difficulty splitting them.
Steady atmospheric seeing is desired.
Best observed when the double star has an altitude higher than 30º.

Coma Berenices Open Cluster
aka Melotte 111

Easily visible in the early evening from mid March through July.

The two-dimensional celestial dome is deceiving in regard to the true spacing of stars in three-dimensional space.

Melotte 111 is thought to have over 40 stellar members, most being below naked eye visibility down to 9th and 10th magnitude.

The galaxies shown are typically 150,000 times farther than the Coma Bernices Open Cluster (Melotte 111).

Gamma, the brightest member, is not a true member of the cluster, but a foreground star.

The brighter stars of the cluster are on the order of 10-20 light-years apart from each other.

The volume is filled with 5 times as many stars as shown, but most of those are fainter than 8th magnitude.

B35: A Deep, Dark Nebulae
Test your observing skill at low magnification

Appearing as a dark hole in the winter's sky, B35 is a dark nebulae with relatively high opacity.

How to find B35:
1. Look for the bright star Betelgeuse in the northeast corner of Orion.
2. 6º northwest of Betelgeuse is 3.4 magnitude Lambda Orionis, primary star of the "Orion's Head Nebula," also known as Collinder 69.
3. Midway between Betelgeuse and Lambda hides B 35.

How to view B35:
• Use a low magnification.
• Transparent, dark skies are a must.
• Must be able to distinguish small differences in contrast.
• View when no moon is present.
• Best seen near culmination.