The comet – which is currently also visible to the naked eye from the Netherlands – is spectacular in several respects.

The comet NEOWISE, discovered in March 2020, keeps the world busy. Because after the comet survived a meeting with our mother star last weekend, it is currently highly visible from the Earth’s surface. And in the Netherlands you can also spot the comet with the naked eye – if you are willing to stay up a little longer.

Parker Solar Probe
But not only interested amateur astronomers are on the edge of their seats. Astronomers are also keeping a close eye on comet NEOWISE. And they use all the tools at their disposal for this, including the Parker Solar Probe, a probe designed to study the sun.

In addition to spectacular photos of NEOWISE, it also provides new information about the comet. For example, cautious indications have now been found that the comet has as many as three tails.

The comet tail
It is without a doubt the most characteristic part of a comet: the comet tail. The tail is created when a comet – which, in short, consists of ice, gas and dust – ventures near the sun and begins to warm up. The ice sublimes (evaporates) and rushes away from the comet, accompanied by dust. This gives the comet a dust tail. In addition, comets also develop an ion tail in such a situation. This tail consists of gas left by the comet, which has been ionized by ultraviolet light from the sun.

NEOWISE, on a photo taken by the Parker Solar Probe. Image: NASA / Johns Hopkins APL / Naval Research Lab / Parker Solar Probe / Brendan Gallagher.

Comet NEOWISE clearly has an ion tail and dust tail. Both are quite visible from Earth. In the case of the dust tail, it is because the dust particles that make up it reflect sunlight. And the ion tail can be seen because the ionized gases glow.

Not two, but three tails
But images taken by the Parker Solar Probe now suggest cautiously that NEOWISE has not two, but three pigtails. It seems that there is a kind of separation in the ion tail. It could mean that the comet has two ion tails next to the dust tail. However, more observations are needed to confirm that.

Here you can see the two clearly visible tails of NEOWISE. The somewhat thicker tail (bottom) is the dust tail. Above you see the ion tail. And now cautious indications have been found that the latter tail actually consists of two parts. Image: NASA / Johns Hopkins APL / Naval Research Lab / Parker Solar Probe / Guillermo Stenborg.

Researchers are watching the comet closely anyway. For example, they want to use the Parker Solar Probe to find out how large the dust particles that NEOWISE shakes off. And at what rate the comet loses dust.

While scientists are addressing these issues, we do well to glance up at the end of the evening or early night and make an effort to spot NEOWISE. Because very often it does not happen that a comet can be seen with the naked eye. And we will never see NEOWISE again anyway; with an orbital period of just under 7,000 years, it no longer ventures near the sun during our lives – or that of the next generations.