13 MOON
Colorado Astronomical Events Calendar
2025
Now in its 6th year of production, this 13 Moon Colorado Astro Events Calendar is much more than a normal calendar, it is a piece of time-art that helps you stay connected to the wonders of the night sky and provides a sense of time based on the natural lunar cycles.
Sky Mesa Temple of Heaven Observatory, located on the south slopes of the Grand Mesa outside of Paonia, Colorado, was founded in 2018 and continues to provide a connection to the celestial realms of the horizon and sky, especially at night.
Also available in-store at the following amazing retailers:
Latest
Phenomenal Airglow
Phenomenal outbreak of emerald green airglow on the night of May 27-28, 2024.
For a mid latitude aurora chaser, bright airglow is often brighter than most aurora encounters, and offer an exhilarating sight to behold and experience. It seems right now in 2023 and 2024, there is almost a monthly occurrence of naked eye visible glow. Space weather research shows that there is a 40% increase in airglow during solar maximum, which is where we are now, so now is a great time to try to catch the phenomenon.
The glow is often visible to the dark-adapted eye as bright ripples or streaks, or even sometimes as an amorphous green glow. The color can be detected as a very faint green or blueish green hue. I liken it to picking out a planetary nebula in a field of stars. One can just tell that it is different! Although it often is mistaken for light pollution or thin high clouds, a long exposure photo will reveal the emerald green glow.
More emerald green airglow from the night of May 27-28, 2024.
Some common characteristics of airglow ripples, rays and banding as seen from locations in west Colorado:
In every instance of ripples or banding that I have seen, the alignment is such that the bands, rays, or spokes stretch out along an east-west line, and tend to be much brighter towards the east, and less bright towards the west.
Also, in every instance, the ripples or rays flow from south towards the north. Timelapse video reveals the direction of travel.
Sometimes the individual rays will appear to pile up towards the north or south, creating thicker and brighter areas in those directions.
Usually lightning is visible towards the east, though not always. However, the lightning seems to enhance or brighten the rays significantly. The series of bright outbreaks that I witnessed in June-July 2023 accompanied intense lighting from sustained super-storm cells over the plains 200 miles to the east. This occurred to the point that I could predict the airglow based on thunderstorm forecasts for the Colorado plains.
Looking east - Intense airglow ripples accompanied by powerful super-storms on June 23 2023.
Another way to tune in is using the handy Sky Quality Meter (SQM) to measure the level of sky darkness. In my experience, strong airglow can brighten the readings by over 0.5 MPSAS compared to a night without airglow. Many, if not most, nights seem to have small amounts of airglow, barely detectable, but can still knock back the SQM reading by 0.1 -0.2 MPSAS.
One proposed theory is that water vapor is the culprit of the diminished darkness as it would back scatter artificial light, however, I have found that a high level of atmospheric water vapor does not necessarily significantly impact sky quality readings, with some of my darkest reading taken just after or between wet storms when there is plenty of water vapor in the air column as seen on NOAA GOES imagery.
Another indicator of airglow is intense lightning. I have witnessed the most intense airglow ripples while also seeing intense lightning out over the eastern plains of Colorado over 200 miles away. I wonder seriously if there is a correlation, in that the upward lightning in the form of sprites, elves, and their associated electric fields stir up the ionosphere and create an impulse that then ripples out. Some say the gravity waves ripple like a stone dropped into a pond, with the storm at the center and concentric circles rippling out, but in my experience, the ripples form instead like spokes on a wheel extending out from the storm at the hub. This leads me to believe that the ripples may form along electric and magnetic field lines created by the intense lightning. Its not just physical gravity waves, there are electric and magnetic fields involved. This has not been confirmed scientifically, though evidence is mounting.
Amorphous green glow - November 2023.
Collage of three different 2023 airglow events with lightning-induced ripples.
Chasing airglow is in my opinion as exciting and rewarding as chasing aurora, if not more so for a mid latitude observer where the pink aurora only occasionally laps at the northern horizon. Once per month encounters can be experienced, at least during solar maximum. The ripples and bands move and cross the Milky Way, making for stunning sights and photographs.
Email skiesalive13@gmail.com if you would like to talk more about airglow.
Read more about the airglow phenomenon:
Photographer Captures Beautiful Aurora-Like ‘Airglow’ in the Night Sky
June 2, 2024
