Stargazers should be in for a pleasant treat if they look up to the night skies on Sunday. As it would seem, a comet commonly referred to as the ‘Christmas Comet’ is expected to present itself as it makes one of its closest approaches to Earth in centuries.
Image Credit: NASA
While it might sound intimidating to think about how an icy space rock is about to make a close approach to Earth, you can calm your nerves. This particular comet will be more than 7.1 million miles away at the time of its closest approach, which equates to approximately 30 lunar distances.
As you might come to expect, this so-called ‘Christmas Comet’ sports a scientific name; astronomers call it 46P/Wirtanen, a name derived from its discoverer, a famed astronomer named Carl Wirtanen. As the comet follows its normal trajectory, it orbits the Sun only once every 5.4 years.
"This will be the closest comet Wirtanen has come to Earth for centuries and the closest it will come to Earth for centuries," explained Paul Chodas from NASA’s Center for Near-Earth Object Studies. "This could be one of the brightest comets in years, offering astronomers an important opportunity to study a comet up close with ground-based telescopes, both optical and radar."
Astronomers have already started spying on 46P/Wirtanen with ground-based telescopes to understand the object in its entirety, but the spying will continue as the comet passes Earth and long after it does.
Observations have already encompassed both optical and radar-based telescopes, which will uncover surface features in more detail. But perhaps one of the most important mysteries astronomers hope to understand better is why the comet ejects so much water given the smaller size of its nucleus.
Although professional astronomers are bringing out the big telescopes to make their observations, NASA notes that you probably won’t need a telescope to observe 46P/Wirtanen for yourself when it makes its closest approach to Earth. Instead, it could be visible with the naked eye or with a simple pair of binoculars.
The best time to search for the comet is around 9 P.M. when the Sun dips far enough below the horizon to eliminate atmospheric light pollution. At that time, you should search in the constellation Taurus near the Pleiades for a bright and hazy gray/green object – this is 46P/Wirtanen.