Comet ‘green’ will be more visible from this Saturday; know how to see

The passage of comet C/2022 E3 (ZTF) can be followed from this weekend in Brazil. With favorable conditions and some techniques, it will even be possible to see the celestial body with the naked eye, although its brightness is at the limit of what the human eye can capture.

To facilitate observation, it is possible to use binoculars, amateur telescopes and even cell phone photos, if the device offers the option of long exposure.

The body has been called a ‘green comet’ because of the predominance of a type of gas in its nucleus.

Its official name, however, is C/2022 E3 (ZTF), because it was discovered in March 2022, in the orbit of Jupiter, by the Zwicky Transient Facility (ZTF) program at the Palomar Observatory in the United States. Find out how to keep up with what may be your last visit.

WHY IS THE COMET GREEN?

According to Filipe Ribeiro, an astronomer and postdoctoral fellow at the National Observatory, the color of comets varies according to the predominant gases in their nucleus. When these gas molecules interact with solar radiation, they produce different types of fluorescence. In the case of the visitor,

WILL IT BE POSSIBLE TO FOLLOW THE COMET?

Ribeiro explains that it will be possible to see the comet from all regions of Brazil. “It started to be visible between the 1st and 2nd of February, but it was very low”, says the astronomer. On Saturday (4) and Sunday (5), visibility increases, because it should appear higher in the sky. Between February 10th and 12th, the comet will be high and close to Mars.

HOW TO SEE THE GREEN COMET?

It is possible to see the comet with the naked eye, but binoculars or amateur telescopes help a lot. On nights this weekend, you need to face north, which can be helped with a compass app, and look for the Capela star at a height of about 30 degrees, according to Ribeiro.

In the following days, the comet will be seen higher and higher and with more visibility. You have to, looking north, look up to a height of 50 degrees or 60 degrees and look for the planet Mars. By locating the red dot, it is possible to search for and identify the comet. The astronomer says that the best period is between 7 pm and 11 pm.

WHAT IF THERE IS NO TELESCOPE OR BINOCULARS NEARBY?

When pinpointing the comet’s location, another tool can help. “You can use a camera, it can be a cell phone, which has the capacity to take long exposure photographs”, says Ribeiro.

With exposures of ten, 15 or 30 seconds, it is possible to identify the comet in the final image, but it is important to keep the cell phone still during the capture.

If the observation fails, there will be a broadcast from the National Observatory on February 11, on the institution’s YouTube channel.

DOES IT PASS NEAR THE EARTH AGAIN?

With orbits classified as eccentric, different from that of planet Earth, for example, comets take time to return to places where they have already passed. If the ‘green’ comet ever passed close to our planet, it is estimated that it must have been around 50,000 years ago. For that very reason, this may be the last visit, as it may already be outside the sun’s orbit.

WHAT IS A COMET MADE OF?

Comets are masses of ice and rock that, when approaching the Sun, produce a tail, with the sublimation of volatile material on their surface. According to Ribeiro, our solar system has a kind of comet reservoir, which is the star Oort, located probably 1.87 light-years from Earth.