Earlier this month the Geminid meteor showers were visible to us and the Ursid meteor showers peaked at the solstice. I wrote last week about the theory that the Christmas Star of Bethlehem may have been a comet. Our 2016/2017 New Year comet visitor is the periodic comet 45p (AKA Honda-Mrkos-Pajdušáková).
I doubt that you and I will catch sight of Comet 45P. It will be up there in the heavens now along with a crescent Moon. Being a periodic comet, it appears every 5.25 years. It is expected to reach maximum brightness and be closest to Earth in February 2017, but I have read online that it should be binocular and telescope visible to we amateurs sometimes from January through February 2017.
The comet will reach perihelion (closest to the Sun) tonight, December 29, 2016, which will increase its head and tail. It passes just 7.4 million miles from the Earth on February 11th at 14:44 UT.
A comet is an icy body that releases gas or dust. They are often compared to “dirty snowballs,” though recent research has led some scientists to call them snowy dirtballs. Comets contain dust, ice, carbon dioxide, ammonia, methane and more.
When passing close to the Sun, a comet warms and begins to evolve gasses. This “outgassing” produces a visible atmosphere (coma) and sometimes also a tail.
Is a comet a “shooting star?” No, and a shooting (or falling) star has nothing to do with stars. Those streaks of light you can sometimes see in the night sky are caused by tiny bits of dust and rock called meteoroids falling into the Earth’s atmosphere and burning up. The short-lived trail of light the burning meteoroid produces is called a meteor. If any part of the meteoroid survives burning up and actually hits the Earth, that remaining bit is then called a meteorite.
A comet is a celestial body moving about the sun and it will not enter Earth’s atmosphere. They usually have a pretty eccentric orbit.
Comet 45P is towards the center of the Milky Way Galaxy in Sagittarius. At its brightest, it will be passing through the constellation Hercules during closest approach on February 11th. During the second week of February, the comet is visible in the dawn sky 82 degrees west of the sun at maximum brightness. This view will be best in the northern hemisphere.