Blue Moon

Blue moon

A blue moon refers to the presence of a second full moon in a calendar month, the third full moon in a season containing four, or a moon that appears blue due to atmospheric effects.

Blue Moon (spacecraft)

Blue Moon is a family of lunar landers and their associated infrastructure, intended to carry humans and cargo to the Moon, under development by a consortium led by Blue Origin and including Lockheed Martin, Draper, Boeing, Astrobotic, and Honeybee Robotics. Two versions of Blue Moon are under development: a robotic lander originally planned to land on the Moon in 2024 and delayed to 2026, and a larger human lander planned to land a crew of four astronauts on the lunar surface for NASA's Artemis program.

Moon

The Moon is the only natural satellite of Earth. It orbits Earth in an elliptical path, at a distance that varies over the year, averaging around 378,000 kilometers (235,000 mi). It completes an orbit in relation to Earth and the Sun (synodically) every 29.5 days. The Moon and Earth are bound by gravitational attraction, which is stronger on the sides facing each other. The resulting tidal forces are the main driver of Earth's tides, and have pulled the Moon to always face Earth with the same near side. This tidal locking effectively synchronizes the Moon's rotation period to its orbital period.

Blue

Blue is one of the three primary colours in the RGB (additive) colour model, as well as in the RYB colour model. It lies between violet and cyan on the spectrum of visible light. The term blue generally describes colours perceived by humans observing light with a dominant wavelength between approximately 450 and 495 nanometres. The clear daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering. An optical effect called the Tyndall effect explains blue eyes. Distant objects appear more blue because of another optical effect called aerial perspective.

blue moon

Noun

1. An extra full moon that appears in a subdivision of a year, namely.