The Alpha Centaurid Meteors are visible in the Southern Hemisphere (but
not the Northern Hemisphere) between 28 January and 21 February each
year, peaking on 8 February, with best viewing at about 5.00 am local
time wherever you are, with about 1 meteor per hour appearing to radiate
from a point close to the star Alpha Centuari (the radiant point). The
Alpha Centaurids can be difficult to spot, not just because of their low
density, but because they are among the fastest meteors, crossing the
sky and disappearing very quickly; in 2020 this will not be helped by
the waxing Moon, which will be full on 9 February, making meteor viewing difficult over this time.
The radiant point (point from which the meteors appear to radiate) of the Alpha Centaurid Meteors. The Sky Live.
Metoer showers are thought to be largely composed of material from the
tails of comets. Comets are composed largely of ice (mostly water and
carbon
dioxide), and when they fall into the inner Solar System the outer
layers of this boil away, forming a visible tail (which always points
away from the Sun, not in the direction the comet is coming from, as our
Earth-bound experience would lead us to expect). Particles of rock and
dust from within the comet are freed by this melting (strictly
sublimation) of the comet into the tail and continue to orbit in the
same path as the comet, falling behind over time. The parent body of the
Alpha Centaurids is not known, though the path which the meteors follow
is; this follows an elliptical path tilted at 105° to the plane of the
Solar System, with its perihelion (closest point to the Sun) at about 1
AU (i.e. the same distance from the Sun as the Earth) and an average
distance from the Sun of 2.5 AU (about 2.5 times as far from the Sun as
the Earth.
The Earth passing through a stream of comet dust, resulting in a meteor shower. Not to scale. Astro Bob.
See also...
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