“Venera-D”: Russian scientists proposed to land the apparatus on the Venusian volcano Idunn

As we know, Roscosmos plans to launch its mission to Venus by 2029-2031, for the first time in modern Russian history. The scientific part of the Venera-D, which is the responsibility of scientists from the Space Research Institute of the Russian Academy of Sciences, began to be actively worked out last year – from 2024 it is planned to start creating a draft design of the device itself, for which NPO named after N.I. Lavochkin. But before turning to the scientific goals of the project, let us briefly recall the results of previous studies.

Venus is very similar in size and mass to the Earth and, most likely, at an early stage evolved according to the same scenario as our planet. Unraveling its mystery would mean unraveling our future. The Soviet Union was the first country to land its apparatus on a hot planet. Starting from 1961, 19 (!) devices were sent to a distance of up to 40 million kilometers. 8 Venus and 2 Vega managed to land on the planet, and they transmitted a lot of valuable data to Earth.

The contribution of Soviet scientists

Thanks to the Soviet “Venus”, people learned that the temperature on the surface of the planet reaches 470 degrees Celsius, the pressure is 92 atmospheres, and the clouds do not consist of water and ice, like ours, but of droplets of sulfuric acid. Our instruments have for the first time measured the level of illumination of the planet under a dense layer of clouds. It turned out that up to 10% of the sun’s rays reach it, which is why deep twilight is observed there even during the day, and pitch darkness at night, because Venus does not have a bright satellite like our Moon. Thanks to “Venus”, mankind has learned that the surface of the planet of the same name has a reddish tint, and the sky is orange. For the first time, panoramas were transmitted from the surface of the planet – first in black and white, and then (from Venera-13 and Venera-14) and color, which made it possible to see its unusual landscape and draw certain conclusions about the geological past. And finally, it was thanks to Soviet scientists that the first maps of the surface of Venus were obtained for the first time – they were made with the help of radars from space orbiters. Until 1985, two Soviet vehicles Vega-1 and Vega-2 were also sent to Venus. They conducted a study of the soil of Venus and for the first time studied the Venusian atmosphere with the help of balloons separated from them: this was the first experience of aeronautics through an extraterrestrial atmosphere in history.

International and foreign missions

In the 1960s and 70s, the American orbital interplanetary stations Mariner, Pioneer Venus (Pioneer Venus), and Magellan flew up to Venus. The last few years of work (from 1989 to 1994) managed to carry out a more in-depth mapping of the planet compared to ours and take the most detailed pictures of the entire surface.

Eleven years after Magellan, in 2005, the European Venera Express station set off for Venus for the first time, and in 2010, the Japanese Akatsuki spacecraft, which still flies. We asked Dmitry GORINOV, leader of the development of the scientific program of the complex of scientific equipment of the Venera-D space complex from the Research Institute of the Russian Academy of Sciences, to tell us about the fact that they managed to explore something new, unlike the Soviet Venus and Veg.

“One of the discoveries of Venera Express was molecular glows in the planet’s mesosphere, which were an important indicator of how other dynamic processes take place in the upper atmosphere,” the scientist says. – A polar orbit was chosen for Venera Express, thanks to which we first saw the pole of Venus with its characteristic dipole vortex. In addition, one of the brightest discoveries was the uneven distribution of the thermal glow of the planet’s surface in the infrared range – certain areas of Venus glow brighter than others. Correlating them with a map of the planet, we realized that the detected thermal anomalies could be a sign of active volcanoes from which lava erupts.

As for the Akatsuki apparatus, in 2015 it was put into a highly elongated elliptical orbit around Venus, in which it still flies. On the Japanese apparatus of the devices – only cameras. So the one that shoots in the far infrared “saw” an unusual phenomenon: a stationary thermal feature above the equatorial hill, which is called Aphrodite’s Land. This feature is located at an altitude of about 70 km above the surface.

– What is this phenomenon, how did you manage to understand it?

“To do this, I must first describe to you the atmosphere of Venus. Near its surface, the air is very dense, about 1/10 of the density of water, this is a supercritical state of air that occurs at the highest temperature and pressure. This massive, very heavy atmosphere, moving horizontally, always in the same direction, suddenly collides with a hill, a mountain range. From this interaction, a stationary gravitational wave arises, propagating upwards towards the cloud layer. This process gives rise to a region darkened in the infrared range at the height of the upper boundary of the clouds. At the same time, it should be noted that at an altitude of 70 kilometers, the Venusian wind blows at a tremendous speed (about 100 m / s), bending around the entire planet in 4 days. And this “feature” stands at the equator, surrounded by a powerful atmospheric flow and does not move anywhere.

Help “MK” Venusian days (243 Earth days) last longer than a year (225 Earth days), that is, the planet rotates faster around the Sun than around its axis. And the atmosphere of Venus rotates faster than the planet itself, 60 (!) Times.

According to Gorinov, there is evidence that a similar effect of the surface on the circulation of the atmosphere exists not only above the Earth of Aphrodite, but also in other places on the planet where significant elevations are present.

Future plans

These and many other assumptions will have to be tested by the new Venera-D station. Experts are already discussing a landing site for him. In particular, there is an idea to land the apparatus on the slope of the young and most likely active Idunn volcano.

– If we sat down on Idunn (from the Earth volcano Etna is the most similar to it), we could explore fresh (by geological standards) samples of the bowels of Venus, which erupted and flowed down the slope relatively recently, maybe even just a few years ago , says my interlocutor.

What if it’s an active volcano?

– Maybe so, there is a certain risk of losing the apparatus, but Idunn does not erupt 24 hours a day, 7 days a week. Like terrestrial volcanoes, it most likely erupts lava much less frequently. But, of course, this idea has one more significant disadvantage even without a volcanic eruption. For example, the device will not be too comfortable to land on its sloping slope (although the design in theory can withstand a 15-30-degree slope). Therefore, the flat regional plains of Venus, containing a representative, common type of soil, are still recognized as the most rational place for landing “Venus-D”. The program of scientific research includes its collection and research.

“But after all, many years ago, our Soviet scientists already planted devices on the plain and took away the soil …

– Yes, there were landings earlier, but not aimed, but blindly: both on the plains and on the slopes, however, these were not volcanoes.

– So what new should the new mission bring?

– Our lander, according to the plan, should work for about 2 hours. The soil, after sampling from a 3-cm depth, will be analyzed using the most modern instruments: they will determine both the chemical and mineralogical compositions, and the isotope ratios of elements orders of magnitude more accurately than was done before. In the new project, we will again have balloons for a longer and more in-depth study of the atmosphere, composition and parameters of clouds. We will seriously look for biomarkers like phosphine – this is a sensational topic widely discussed by researchers around the world.

Help “MK”. Phosphine, hydrogen fluoride, was detected on the upper edge of the clouds of Venus in 2020 using the James Clark Maxwell Telescope in Hawaii and the Atacama Large Millimeter-Wave Array in Chile. It is known that phosphine is produced by microorganisms, but it can also have another, for example, volcanic, origin. Recent studies, moreover, have shown that “Venusian phosphine” in its spectral features is close to sulfur dioxide, which calls into question the fact of its presence in the atmosphere.

– The Venera-D project was originally planned as a joint project with the United States, but the cooperation eventually fell apart. What will the scientific program lose because of this collapse?

– Together with the Americans, we planned to send long-lived landing stations to Venus that could work up to 30-60 days. These vehicles were to be built with high-temperature electronics capable of withstanding the harsh conditions of Venus. Such a period of operation of the equipment would make it possible for the first time to study the seismic activity of the planet.

– But the Americans and Europeans are preparing their missions to Venus, on which they could realize their plans.

– Long-lived landing stations, unfortunately, were not included in any of the projects they are currently developing. The missions planned by NASA and ESA mostly consist of only orbiters. However, the Americans in their project DAVINCI (“Da Vinci”) have a descent vehicle, but it does not involve a soft landing, its main purpose will be to conduct atmospheric measurements during the descent in the atmosphere.

In general, we need to wait another six or eight years, and we will see if our scientists and designers will be able to regain their former technological advantage in research on the “Russian” planet Venus, which was most favorable to us in the past.