The curious the northern hemisphere will have the chance to spot a solar system comet as the celestial object hurtles through space very close to Earth for the first time in 50,000 years.
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Look up at the sky Wednesday night through Thursday as the comet called C/2022 E3 (ZTF) was visible to the naked eye nearly 50,000 years ago, around the time of Neanderthal man. If you miss it this time, you probably won’t get another chance.
Haven’t you seen the green comet ZTF in the last few weeks? Tonight is the perfect moment because on February 2, 2023, the historic comet will make its closest approach to our planet.
A relative closeness, of course, since it happens just over 42 million kilometers from Earth. At its closest position, the comet will be less than 16 million miles away, according to the Adler Planetarium.
The closer it got to Earth, the brighter and more visible the comet became. This Wednesday, it orbits the Sun at a speed of 207,000 km/h between the orbits of Earth and Mars.
It has been observable without a scientific instrument since January 19, and by Wednesday evening it will be bright enough to be seen through telescopes and binoculars.
Comets can be difficult to spot in the night sky, but the cosmic intruder has steadily brightened with its movements, which NASA says should help people spot it.
Astronomers estimate that the comet has a nucleus 1.6 km in diameter and its tails stretch for millions of kilometers. The green comet poses no threat to the planet.
C/2022 E3 (ZTF) was discovered in March 2022 by astronomers using the surveillance camera at the Zwicky Transient Facility north of San Diego in California, USA.
Comets are fairly common to scientists as they are icy remnants of the solar system’s formation 4.5 billion years ago.
Comet C/2022 E3 (ZTF) has a long orbit that will take it thousands of years to travel around the sun and deep into the vast solar system.
how to see it
To watch the passage of the green comet, you need to look at the right stars. It is advisable to observe the sky in a north-easterly direction from a very dark place and look for a spot in the sky, or in the hours before dawn after the moon has fallen below the horizon.
According to EarthSky.org, the comet will pass under Polaris, the North Star at the tip of Ursa Minor, and will be visible near the star. And on February 10, the comet will come very close to the planet Mars. If you can locate Mars bright in the sky, look around for the comet.
Maps are available online to help you locate reference points like Hercules, Polaris, and Mars in the night sky. You can also try your hand at stargazing apps that will make it easier for you.
why is it green
With binoculars, the comet appears as a faint green glow in the sky. It also has “a short, broad dust tail and a long, faint ion tail,” according to NASA.
Its emerald hues come from the presence of diatomic carbon in the gas cloud that surrounds its core and interacts with sunlight, according to astronomy experts.
When diatomic carbon, an unstable gaseous form of the element in which carbon atoms are bonded in pairs, is excited by ultraviolet rays, it emits light and causes the green cloud seen around the comet’s nucleus.
However, ultraviolet light can also cause diatomic carbon to break down. This explains why the comet’s tail is not green but white.
For those unable to see the Green Comet in person, real-time images will be webcast from robotic telescopes in Italy and Spain.