Las Cruces Clear Sky Clock

Speaker: Fred Pilcher
Topic: "Yarkovsky and YORP, or How Lowly Photons Control the Destiny of Planets"

Location: Dona Ana Community College
(Main Branch)
Room 77 (map)

Contact the Club President for additional information

Upcoming Observing Opportunities:

ASLC MoonGaze
(Int'l Delights Cafe)
Sat, January 29th (dusk)

Monthly Dark Sky Viewing
(Upham Site)
Sat, January 21st (dusk)

   Quick Links

• Home Page
• Telescope Basics
• Monthly Observing Highlights
• Request a Star Party for your Group or School
• Request a Educationl Visit by an Astronomer to Your Club or School
• This Month's Sky Map
• Observing Sites (maps)
• The Science of ASLC
  • Asteroid LightCurves
  • Minor Planet Discovery
  • Variable Stars
  • Occultation Timing
• Telescope Making
• Light Pollution Facts
• Club By-Laws
• ASLC's Observatory
• Upcoming Clinics
• Astronomical Glossary
• Classified Ads
• Join ASLC

Welcome!

Greetings from the professional and amateur astronomers who comprise the Astronomical Society of Las Cruces (ASLC). The club was formed in 1951 by a group of dedicated astronomers including Clyde Tombaugh, who had discovered Pluto just 21 years earlier. For nearly 60 years, we've been sharing a little bit of the universe with our community under our beautiful Southern New Mexico skies.

The club has a variety of ongoing observing, education and public outreach programs. We host a public Moongaze each month, offer beginning astronomy courses and support countless star parties for schools, scouts and various organizations. We also hold a meeting each month which includes a featured presentation.

To learn more about our society, please click here or select from the tabs above or the 'Quick Links' on the left.

 

---

January Meeting

The monthy ASLC meeting will be held on Friday, January 27th at 7:30PM. Club Member Fred Pilcher will be giving a talk titled "Yarkovsky and YORP, or How Lowly Photons Control the Destiny of Planets".

All objects with temperature above absolute zero, that is of course all objects, radiate electromagnetic radiation. By the De Broglie relation the photons of this radiation carry momentum. Radiation from a surface is therefore analogous to rocket exhaust, and the radiating object recoils like the rocket body. The recoil is very small, of course, and completely negligible for larger bodies. For objects of 60 kilometers and smaller the net effect over the lifetime of the solar system can be large. Bodies of these sizes can move toward or away from the Sun, or be deflected into orbits crossing the major planets. The rotation periods can increase or decrease, sometimes by large amounts, the axes of rotation can reorient in space, and a piece can detach to become an orbiting satellite or in some cases move away to become an independent Sun orbiting object. The Yarkovsky effect has a major role in delivering killer asteroids to the Earth.

---

NMSU Astronomy Open House January 27th

The NMSU Department of Astronomy will hold an Observatory Open House at 7 p.m. Friday, Jan. 27, at the NMSU campus observatory. Everyone is welcome to come and spend an evening of stargazing. Admission is free and children are especially welcome to attend. Astronomy personnel on hand will be Nicole Vogt, and graduate assistants Kenza Arraki, Kyle DeGrave and Kyle Uckert. Professor Nicole Vogt will present a short astronomical film. Sky viewing through telescopes will include the crescent Moon, the planets Venus, Mars and Jupiter, Orion the Hunter and the Gemini Twins Castor and Pollux.

For more information call 646-4438 or visit the NMSU Astronomy Department website.

 

---

ASLC Photo of the Week - M46 by Chuck Sterling

Open Cluster M46 is in constellation Puppis. M46 is about 5,500 light-years away with an estimated age on the order of several hundred million years. The planetary nebula NGC 2438 appears to lie within the cluster near its northern edge (the faint doughnut at the right center of the cluster). NGC 2438 is most likely unrelated since it does not share the cluster's radial velocity, and just happens to be in the same field of view.

The image was acquired from his back yard in Las Cruces, NM, using Images Plus Camera Control 2.0 with a Canon 350d camera on an Astro Tech 8" f/4 imaging newtonian, with an IDAS LPS-P1 light pollution filter and a Baader MPCC (multi-purpose coma corrector). The mount is a Celestron CGE, autoguided by PHDGuide 1.12.3 and a ShoeString Astronomy GPUSB with a Meade DSI-Pro-1 camera on an Orion 80ED f/7.5 refractor.

Clicking on the image will take you to a larger version on Chuck's website.

  
The Astronomical Society of Las Cruces is a proud member of the Astronomical League