Meteors on Venus Fall Noticeably Brighter, More Frequent, and Faster than on Earth, Physicists Find Out

11:15, June 25, 2024

Scientists have proposed a way to observe meteor phenomena in the atmosphere of Venus

Physicists have calculated how meteoroids fall on Venus. According to the scientists' calculations, meteors in the atmosphere of Venus should be visible earlier than on Earth (the glow occurs higher in the atmosphere), they are brighter, fall faster, and the visible trail is shorter. Description and results of the model of the formation of meteor glow when meteoroids enter the atmosphere of Venus researchers published in the journal Icarus. The work was supported by the Academy of Finland, the Finnish Institute of Geospatial Research (project no. 325806), and the Priority 2030 development program.

"Using a physical model of meteoroid glow formation during meteoroid ablation, we have shown that Venusian meteors fall brighter, shorter, and higher in the atmosphere than terrestrial meteors. The main reason for these differences is the Venusian atmosphere, which is about 100 times denser than the Earth's atmosphere", said Apostolos Christou, co-author of the paper and Research Astronomer at Armagh Observatory and Planetarium in Northern Ireland, UK.

As a meteoroid enters the atmosphere, it collects more and more air in its path, scientists explain. At some point, the meteor body and the hot air plasma surrounding it begin to glow, and the so-called luminous trajectory of the bolide's fall becomes visible.

"All other things being equal, meteors on Venus will begin to glow higher than on Earth. Because of the higher atmospheric density, the bolide will glow brighter and will experience higher loads. For this reason, the number of meteors observed by a camera orbiting Venus will be 1.5-2.5 times higher than the number of meteors observed by an Earth satellite in the same configuration", explains Maria Gritsevich, co-author of the work, Adjunct Professor at the University of Helsinki and Senior Researcher at the Ural Federal University.

Observations can confirm or correct the calculations of physicists. Scientists believe that all the conditions for this are in place - the European Space Agency is preparing for the Venus orbital mission EnVision, where a suitable camera could be adapted for observations. As an example, scientists cite the Mini-Euso camera, which has been operating on the International Space Station since 2019 and has collected an impressive amount of data. As the physicists explain, it would be easier to record bolides on Venus (since they enter the atmosphere earlier) from a satellite than on Earth. The only difficulty lies in transmitting a large amount of data to Earth, but even for this task, scientists have solutions. 

The scientists add that traditional optical observations using the sky recorder or video recorders from the surface of Venus would be impossible.

"The atmosphere of Venus is known for its high density and turbidity, which makes clear optical observations from the planet's surface much more difficult. Observations from orbit are therefore preferable and easier. Instruments orbiting Venus can operate more efficiently, bypass the influence of dense atmospheric layers and clouds, and provide reliable observations of meteors and other atmospheric phenomena", notes Maria Gritsevich.

Several factors, including Venus' relative accessibility compared to other planets in the solar system and its dense atmosphere, make the planet an ideal location for the first extraterrestrial meteor surveys, physicists believe.

"The observations will allow us to estimate the number of meteoroids colliding with Venus and will bring us closer to understanding the overall distribution of meteoroids in the Solar System: their velocities, orbits, sizes, and compositions. This will greatly increase the chances of detecting interstellar and intergalactic meteoroids entering our Solar System from a distance. This approach also contributes to a deeper understanding of the formation and evolution of our Solar System, including important aspects of its chemical and physical evolution", says Maria Gritsevich.

Christou and Gritsevich hope to one day have cameras aboard the orbiter to observe the spectacular meteor showers caused by previously unknown streams of comets crossing Venus' orbit.

Reference

Venus is the second from the sun and the sixth largest planet. It is the hottest planet in our solar system: the temperature on Venus is about 475 degrees Celsius. It orbits the Sun at a distance of 0.72 astronomical units (almost 108 million kilometers). The atmosphere of Venus consists of carbon dioxide - 96.5%, nitrogen - 3.3%, and small impurities: CO, SO2, Ar, H2O, and others. Oxygen has not been detected in significant amounts.

The surface of the planet is always covered by clouds consisting of droplets of 75-80% sulfuric acid solution. The three main cloud layers are between 75 and 49 km high. They differ in the concentration of the droplets - acid aerosols - and some variation in their size, from one to five microns. Particles of solid sulfur are also present in the lowest layer of clouds. Clouds represent a light mist, but because of their long vertical extent, they completely shield the planet's surface from observation in all ranges of the electromagnetic radiation spectrum except radio waves.

Venus is similar in size to Earth: the diameter of the equator of the first planet is 12,104 kilometers, and the diameter of the equator of the second planet is 12,756 kilometers. One "day" on Venus lasts 243 Earth days, one year (one orbit around the Sun) - 225 Earth days. The Venera probes sent by the USSR from 1961 to 1984 took photographs of the surface of Venus, which show - a barren, dull, and rocky landscape, and the sky is probably a shade of sulfur yellow.

Anna Marinovich

The news article was translated by UrFU International Marketing Office.
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