2012
Comet Encke has an orbital period of about 3.3 years, so it will next be visible from Earth in 2024. However, it may not always be visible to the naked eye depending on its position in the sky and proximity to the Earth.
The next notable comet scheduled to pass by Earth is Comet Leonard, which is expected to be visible in December 2021. It will be the brightest comet of the year and should be observable with binoculars or a small telescope from dark sky locations. Keep an eye out for updates from astronomers as the date approaches for the best viewing opportunities.
Isaac Newton
Comet Encke's density is estimated to be very low, around 0.6 grams per cubic centimeter. This low density is due to its composition of ice, dust, and rocky material, which is less dense compared to solid rock.
Not all comets have their orbits calculated so it is impossible to say.
comet 99947 (zorton 47) is coming in 2016
It's unclear what you mean by "hades comet." If you are referring to a comet named Hades, there is no specific comet with that name. If you meant Halley's Comet, it will next be visible from Earth in 2061.
The next visible comet that is expected to be visible to the naked eye is Comet Leonard in late 2021.
Comets have a stream of gas and dust coming off them.
around 2061
The next notable comet expected to be visible in the northern hemisphere is Comet Leonard (C/2021 A1) in December 2021. This comet is predicted to be visible to the naked eye and is anticipated to be a significant event for skywatchers.
The next comet will be Comet Ison which will pass by the earth in 2013. It will be visible with lenses during late summer and will be visible to the naked eye by approximately November.