A couple of weeks ago, Radiolab aired an episode about a puzzling object on a children’s poster of the solar system: a Venusian moon called Zoozve. Venus doesn’t have any moons and “Zoozve” didn’t show up on Google at all, so co-host Latif Nasser went on a bit of a mission to find out what the heck this object was. He talked to someone at NASA, the poster’s designer, and various astronomers and physicists, including the person who had discovered Zoozve (aka 2002 VE68).
So begins a tiny mystery that leads to a newly discovered kind of object in our solar system, one that is simultaneously a moon, but also not a moon, and one that waltzes its way into asking one of the most profound questions about our universe: How predictable is it, really? And what does that mean for our place in it?
The astronomers, who reported the finding on Monday in a pair of papers, have not collected specimens of Venusian microbes, nor have they snapped any pictures of them. But with powerful telescopes, they have detected a chemical — phosphine — in the thick Venus atmosphere. After much analysis, the scientists assert that something now alive is the only explanation for the chemical’s source.
Some researchers question this hypothesis, and they suggest instead that the gas could result from unexplained atmospheric or geologic processes on a planet that remains mysterious. But the finding will also encourage some planetary scientists to ask whether humanity has overlooked a planet that may have once been more Earthlike than any other world in our solar system.
“This is an astonishing and ‘out of the blue’ finding,” said Sara Seager, a planetary scientist at the Massachusetts Institute of Technology and an author of the papers (one published in Nature Astronomy and another submitted to the journal Astrobiology). “It will definitely fuel more research into the possibilities for life in Venus’s atmosphere.”
If you look at the orbits of the planets adjacent to the Earth’s orbit (Venus & Mars), you’ll see that Venus’s orbit is closest to our own. That is, at its closest approach, Venus gets closer to Earth than any other planet. But what about the average distance?
According to this article in Physics Today by Tom Stockman, Gabriel Monroe, and Samuel Cordner, if you run a simulation and do a proper calculation, you’ll find that Mercury, and not Venus or Mars, is Earth’s closest neighbor on average (and spends more time as Earth’s closest neighbor than any other planet):
Although it feels intuitive that the average distance between every point on two concentric ellipses would be the difference in their radii, in reality that difference determines only the average distance of the ellipses’ closest points. Indeed, when Earth and Venus are at their closest approach, their separation is roughly 0.28 AU — no other planet gets nearer to Earth. But just as often, the two planets are at their most distant, when Venus is on the side of the Sun opposite Earth, 1.72 AU away. We can improve the flawed calculation by averaging the distances of closest and farthest approach (resulting in an average distance of 1 AU between Earth and Venus), but finding the true solution requires a bit more effort.
What the calculation also shows is that Mercury is the closest planetary neighbor to every planet, on average. Also, the authors of the paper don’t explicitly mention this, but the Sun (at 1 AU) is closer on average to the Earth than even Mercury (1.04 AU).
Last year, Eleanor Lutz made a medieval-style map of Mars. As a follow-up, she’s made a topographical map of Venus. The features on Venus are named for female mythological figures & notable women and Lutz provides a small biography for each one on the map. Among those featured on the map are:
Anne Frank
Selu (Cherokee Corn Goddess)
Kali (Hindu Goddess, Mother of Death)
Virginia Woolf
Sedna (Eskimo Whose Fingers Became Seals and Whales)
Ubastet (Egyptian Cat Goddess)
Beatrix Potter
Edith Piaf
Venus passed in front of the Sun yesterday for the last time until 2117. The transit took almost seven hours but this NASA video shows it in under a minute.
Stay Connected