The second-closest planet to the sun is more geologically active than we thought and could have more than 17,000 venusquakes a year.
There could be thousands of quakes on Venus each year, and we might be able to detect them using balloons floating high above the planet’s surface.
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| Venus may have regular quakes linked to the activity of volcanoes like the giant Maat Mons, which towers nearly 5 kilometres above the surrounding plains NASA/JPL |
Recent observations of volcanic features on Venus, such as vents and lava streams, have shown the planet is much more geologically active than we thought. This makes it more likely that there is also seismic activity, or quakes, on Venus, Iris van Zelst at the German Aerospace Center told the Europlanet Science Congress in Berlin on 13 September.
To work out how frequently and where these venusquakes might occur, Zelst and her colleagues used Earth’s linked geologic and seismic record as a guide, because Earth and Venus are the most similar planets in terms of their size, mass and composition.
The researchers looked at the relationship between Earth’s geological features, such as where tectonic plates and ridges are, and how frequently quakes occur, and then used a similar map of Venus’s tectonic features, consisting of large rings called coronae and tectonic plate-like ridges, to predict where and how many of these quakes might happen. “If we assume some of these [features] might be active, what is the kind of seismicity we would get?” said Zelst.
They found that a seismically active Venus could have at least 1161 quakes per Earth year that are above a magnitude 4, which would feel relatively weak on Earth, and as many as 17,773 above that level if Venus is extremely seismically active.
Detecting quakes on Venus’s surface could be harder than it is on Earth or Mars because of the hot temperatures. These average 464°C (867°F), potentially making it difficult for spacecraft to land and operate, but it might be feasible to make ground-based measurements.
It might also be possible to take seismic measurements in the air. Venus’s atmosphere is so thick that quakes on the ground could propagate upwards through the dense gas, and be detectable by a kind of weather balloon, says Aymeric Spiga at Sorbonne University in Paris, France. “It’s pretty exciting because you have not only one method, but two so that you can compare between them,” he says.