What Are Comets?

Where you can enjoy learning about space.

What Are Comets?

A comet is a small mass in the solar system composed of particles of dust, rock, and ice. Comet appearances are in comparison to "dirty snowballs" of gases, dust, and rock. Each comet is a small system within a larger system.

Orbits of Comets

Comets orbit the Sun, their orbits can be long ellipses, or elongated circles depending on what they are made out of and where they come from. One full orbit of a comet takes hundreds to even thousands of years to complete so we only see them for a few weeks when they are close to the Sun. An interesting fact is that comets speed up when they are close to the Sun, and slow down when they are in the far outreaches of space.

Fun Fact!

Did you know that comets can vary from sizes of small towns to the sizes of a mountain on Earth?

Anatomy of a Comet

Due to high temperatures and nuclear fusions in the center of the solar system, when the comet's orbit reaches the Sun, it's layer of ices melts and leaves a trail of dust and ice, also known as the tail. The gas and dust form an outer layer called the coma, which makes up the comet's brightest part, the head. If a comet were to hit a planet or moon, they would leave behind gigantic craters, almost the size of Earth itself but we are safe of that happening anytime soon.

Did you know that comet tails always point away from the Sun?

What are Comets?

Tails of a Comet

The particles that make up an ion tail stretch away from the Sun and change direction a lot. I wonder whether the changing of direction is caused by the comet's orbital path. Comet tails can be seen from Earth and add very little mass to the overall comet's weight, so they can easily be blown away by solar winds.

Orbital Periods

Periodics: This term means that a comet can be visual at fixed dates, equal intervals apart. For example, the Encke's Comet can be seen every 1,206 days.

First Comet Sighting

In 1781, German-born musician and astronomer William Herschel was one of the first people to spot a comet through his HOMEMADE TELESCOPE!! Interesting!

Halley's Comet

This famous comet was named after an English astronomer, Edmond Halley. It was sighted in 1835 when the comet was in the sky, and again in 1910 on it's next visit. It is predicted to be spotted with a periodic of 76 years, when the comet's orbit reaches the Sun.

Is It Worth Watching A Comet In The Night Sky?

Definitely! A comet is one of the most spectacular things you can see in the night sky. Few comets pass Earth, so you are lucky if you see a comet last for maybe days, weeks, or even months!