C/2022 E3 (ZTF), informally called the “Green Comet”, recently made its
closest approach to the Sun, after having traveled tens of thousands of
years from the far fringes of the solar system. It’s forecast to be
brightest around January 31, 2023 and February 1, 2023 at just slightly
brighter than 6th magnitude when the comet is at its closest point to
Earth. But don’t worry. As you are gazing at this cosmic fuzzball,
there’s no threat of it crashing into Earth, as it will be 26 million
miles away from us at its closest approach.
Around 6th magnitude is the faintest an object can be seen without
optical aid in a very clear, very dark sky. A comet that dim won’t look
like popular photos of comets. It will be more like a faint, fuzzy glow
or smear of light. Under a city or suburban sky, you’ll need
binoculars or a small telescope to actually see this comet. Even far
from city lights, you’ll likely need binoculars, too, because when the
comet is brightest, the bright Moon will be in the sky at the same time
This comet is considered a long-period comet, which means its orbit
extends very far out into our solar system from a place that we have
not actually ever observed. The Oort Cloud has only been theoretically
predicted due to the existence of comets like Comet C/2022 E3 (ZTF).
For context, the Oort Cloud is 2000x further from the Sun than the
Earth is to the Sun and Voyager 1 won’t reach the Oort Cloud’s edge for
another 300 years. That’s pretty far away!The last time the Green Comet was visible from Earth would have been
50,000 years ago during the last ice age. Since it came so close to the
Sun during perihelion on January 6, 2023, it is predicted that this
comet will not visit the inner solar system again for at least a
million years. Or it potentially will leave our solar system entirely
This comet is nicknamed the “Green Comet” because of the outgassing of
diatomic carbon that occurs when any comet gets close enough to the Sun
to be heated and then release its trapped gas.
Shot with my Orion EON ED80 & ZWO ASI 071MC PRO One Shot Color Camera.