"The surface of the Earth is the shore of the cosmic ocean... Recently, we've managed to wade a little way out, and the water seems inviting." - Carl Sagan
Comets could arise closer to Earth, study suggests
There’s a potential “cometary graveyard” of inactive comets in our solar system wandering between Mars and Jupiter, a new Colombian research paper says. This contradicts a long-standing view that comets originate on the fringes of the solar system, in the Oort Cloud.
Mysteriously, however, 12 active comets have been seen in and around the asteroid belt. The astronomers theorize there must be a number of inactive comets in this region that flare up when a stray gravitational force from Jupiter nudges the comets so that they receive more energy from the Sun.
The researchers examined comets originating from the main asteroid belt between Mars and Jupiter, a spot where it is believed there are only asteroids (small bodies made up mostly of rock). Comets, by contrast, are a mixture of rocks and ice. The ice melts when the comet gets close to the sun, and can form spectacular tails visible from Earth.
“Imagine all these asteroids going around the Sun for aeons, with no hint of activity,” stated Ignacio Ferrín, who led the research and is a part of the University of Antioquia in Colombia.
“We have found that some of these are not dead rocks after all, but are dormant comets that may yet come back to life if the energy that they receive from the Sun increases by a few per cent.”
Image credit: NASA