A brilliant, bright-green comet with an incredible 11-million-mile long tail makes its once-in-11,597 year trip over planet Earth.

This newly-discovered green-tailed comet from outer space recently made its grand journey through the inner solar system.

The comet soared past Earth before getting closer to the Sun and heading off back through the solar system.

While you didn't need a telescope to see this comet, using binoculars gave us a clear glimpse of the phenomenon.

The massive comet is named Comet Swan or C/2020 F8, and Australian astronomer Michael Mattiazzo discovered it last April.

This comet gets its green tinge from water vapor its icy core releases into space when heated by the Sun.

The vapor then forms 'a cloud of hydrogen that surrounds the comet, giving off a bright spot of Lyman-alpha light.'

The comet ejects more material as it warms up on its way towards the Sun, becoming even brighter.

Astronomers predicted that the snowball would come closest to Earth on May 27, 2020, if it were to survive.

However, comets are fragile bodies. It's challenging to predict the behavior of comets that closely approach the Sun.

According to the European Space Agency (ESA), comets tend to fall apart as they come closer to the Sun. This phenomenon is common in our solar system.

The ESA wrote:

"The comet's [vigor] could be significant for observers on Earth. The more material ejected from the comet, the more sunlight it reflects. And the more visible it becomes."

"Currently moving from the southern to the northern skies, it is just faintly visible to the naked eye. But current estimates suggest that, by the end of May, it could be significantly brighter – if it survives that long."

"…Stargazers on Earth should look for it near the bright star Capella in the constellation of Auriga, the Charioteer."

Amateur astronomer David Blanchflower also gave us tips on how to view Comet Swan. However, he advised it might not be as easy as looking up to the night sky.

He told the Express:

"From the UK, it will be low on the eastern horizon before sunrise. Won't be easy to spot. Binoculars rather than the naked eye would give someone the best chance of seeing it."

"Into next month [June] it will have a better elevation but not predicted to be very bright. So again, binoculars or a small telescope would be needed."

This phenomenon was almost the only time Comet Swan was visible in our lifetimes.

Estimates aren't yet precise, but the comet's orbital period is measured in thousands or even millions of years.

For Comet Swan, it's visible from Earth once in every 11,597 years.