Comets

No, comets do not always maintain the same mass. As they approach the Sun, comets can lose mass through sublimation of ice and dust particles, creating the characteristic glowing coma and tail. This loss of mass can impact a comet's appearance and trajectory over time.

The rocky, gritty material in a cometary nucleus is probably much like a solid asteroid in chemical profile. But most asteroids are solid, barren rock - the comet has a large percentage of ices in it.

This is because it is the center of our solar system. Many items orbit around the sun.

Also, it is unmistakable and almost always visible from some point on the Earth.

There are no other objects in the sky with such a large impact on the Earth.... unless an object from the sky impacts the Earth (like an asteroid).

A space debris that is a mix of rock and ice is typically referred to as a "comet". Comets are celestial objects that orbit the Sun and release gas and dust to form a visible coma or tail when they are close to the Sun. They are considered remnants from the early formation of the solar system.

We expect the only Halley's Comet there is to return to the inner solar system

in 2061. That means it'll get close enough to the sun so that we can see it, but

we can't tell yet exactly how close to earth it's likely to get.

A "vomit comet" is an aeroplane that briefly achieves zero G, allowing people and prospective astronauts to experience weightlessness.

In general, 65 seconds of flight will achieve 25 seconds of weightlessness.

Weightlessness produces nausea and sickness (vomit) in two out of three people and thus the aeroplane earns it's nickname.

Zero Gravity Corporation in the US, will allow you - for a fee (Probably including a cleaning change) - to experience this.

See related link for more information

Halley's Comet is most probably a collection of ice, dust and rocks; a "dirty snowball" may be the most apt description. I'm not sure that "land" would fit the description.

Usually after the people they were spotted by.

The odor-eater insoles contain super activated charcoal that absorbs wetness and bad smells.

Halley's comet got its name from Sir Edmund Halley who, using Newton's laws of motion, predicted that the comet seen in 1531, 1607, and 1682 would return in 1758. Unfortunately, Halley died before seeing the comet return, but when it returned just as he had predicted, the comet was named in his honour by French astronomer Nicolas Louis de Lacaille in 1759.
Halley's Comet was named for Edmond Halley, the English astronomer who identified it as a periodic comet.