SAS astronomers are helping to clarify the orbit of the planet Apophis
These days, planet Apophis, which has been the focus of astronomers around the world since its discovery in 2004, misses the Earth. The first calculations after its discovery showed a 2.7 per cent risk of colliding with the Earth in 2029. Although research from the following years had ruled out a collision with the Earth, this pass will be extremely close. Astronomers from the Slovak Academy of Sciences have been observing and studying the planet from the workstation at Skalnaté pleso for several nights now.
The planet Apophis was named after an ancient Egyptian god from the dark underworld of Apep, who tries to devour the ship of the sun god Ra and deprive people of light.
The object has a surface mainly covered with silicates, a markedly oval shape and an estimated size of 450 meters in the longest and 170 meters in the shortest axis. "Either it is a very elongated single body or two smaller ones connected to each other by a kind of neck,” Marek Husárik from the Astronomical Institute SAS described the observed object and added: "From the first nights we see the effect of the rotation of this considerably elongated ellipsoid, where its brightness changes fluctuating with each observed night."
With their measurements, astronomers from the SAS want to contribute to the clarification of the orbit, which changes not only by the gravitational influences of the Earth and the Moon, but also by the influence of the so-called thermal Yarkovsky effect, when there is a small change in trajectory and a measurable change in the rotation of the body. They also want to specify some of its physical parameters.
On Friday, March 5, 2021, the planet Apophis will be 17 million kilometres from Earth. At the time of the closest pass, which was calculated to be on April 13, 2029, it will be located only 31,200 kilometres from the Earth's surface. "It's amazingly close, because geostationary satellites orbit the Earth at a slightly greater distance of 36,000 kilometres," emphasised the astronomer. From Slovakia, we will be able to observe this extraordinary celestial phenomenon about an hour before midnight in the constellation of Cancer, even with the naked eye.
Spracovala: Katarína Gáliková
Foto: Marek Husárik, Astronomický ústav SAV