2026 January 9

Ice Halos by Moonlight and Sunlight
* Image Credit & Copyright: Antonella Cicala

Explanation:
Both Moon and Sun create beautiful ice halos in planet Earth's sky. In fact, the two brightest celestial beacons are each surrounded by a complex of ice halos in these photos of the sky above Chamonix-Mont-Blanc in France. The panels were recorded one night (left) and the following day at the end of December 2025. Similar ice halos appear in moonlight and sunlight because they are all formed through the geometry of flat, hexagonal ice crystals. The ice crystals reflect and refract light as they flutter in the cold atmosphere above the mountain resort. In the pictures both Moon and Sun are surrounded by a more commonly seen 22 degree circular halo. Bright and sometimes colorful patches at the intersections of the 22 degree circular halos with the indicated parselenic and parhelic arcs are also known as Moon dogs and Sun dogs.
https://apod.nasa.gov/apod/ap241225.html
https://en.wikipedia.org/wiki/Halo_(optical_phenomenon)
https://ui.adsabs.harvard.edu/abs/2022JQSRT.29008313M/abstract
https://cloudatlas.wmo.int/en/parhelic-circle.html
https://apod.nasa.gov/apod/ap160321.html
https://apod.nasa.gov/apod/ap250215.html

https://apod.nasa.gov/apod/ap260109.html

#space #earth #Halo #astrophotography #photography #NASA #science #physics #nature #education

2026 March 25

The Guardians of Rapa Nui beneath the Milky Way
* Image Credit and Copyright: Rositsa Dimitrova
http://instagram.com/tripswithrosie
* Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II)
https://kerockcliffe.com/

Explanation:
In the words of today's astrophotographer, Rositsa Dimitrova, "What have these silent sentinels watched pass across the sky?" The volcanic mo'ai (meaning statue) of Ahu Tongariki stand guard over Rapa Nui (Isla de Pascua, Easter Island), a Polynesian island (annexed by Chile in 1888) located thousands of kilometers off the coast of South America in the Pacific Ocean. Due to the island's remoteness, the mo'ai, with their backs to the dark ocean, are able to gaze upon a clear and vibrant night sky. Pictured, these larger-than-life statues stare at the bright band of the Milky Way, partly obscured by interstellar dust and blurred by Earth's clouds. Under such clear night skies, the Rapa Nui created observatories and used astronomical observations for navigation, calendar calibration, celebrations, and more. Images like this one remind us of the importance of dark skies, protecting the land underneath them, and preserving the culture that they inspire.
https://www.pbs.org/wgbh/nova/easter/civilization/giants.html
https://rapanuitravelguide.com/sightseeing-in-rapa-nui/ahu-tongariki/
https://nativeplanet.tv/episode/respecting-the-moai/
https://smarthistory.org/easter-island-moai/
https://apod.nasa.gov/apod/ap241105.html
https://apod.nasa.gov/apod/ap091012.html
https://science.nasa.gov/mission/webb/science-overview/science-explainers/is-the-milky-way-unique/
https://astronomy.swin.edu.au/cosmos/D/Dust+Grain
https://www.maajournal.com/index.php/maa/article/view/678/614
https://www.americantrails.org/resources/public-lands-preserving-and-protecting-night-skies
https://www.nps.gov/subjects/nightskies/cultural.htm

https://apod.nasa.gov/apod/ap260325.html

#space #earth #milkyway #astrophotography #photography #science #nature #education #apod