Sometimes these incremental  steps are small and seemingly inconsequential. For instance, yesterday CalTech announced the discovery of the first asteroid discovered to have an orbit that is totally contained within Venus’ orbit. This Sun-hugging rock falls into a theorized class of objects called Vatira asteroids. Because objects in this small of an orbit never get very far from the Sun’s position in the sky, they can’t be detected in most surveys, which keep their telescopes away from the horizon. This means that failure to see them in the past wasn’t really surprising, but their are they / aren’t they their unobserved nature was a curiosity. Now, thanks to observations by the Zwick Transient Factory and its twilight observing project, we know there is at least 1 Vatira  asteroid. This object was discovered on January 4 and followup observations allowed a rapid measurement of its orbit. Named 2020 AV2, this object is 1 to 3 km in diameter and orbits the sun every 151 days. It’s orbit isn’t round, but rather swings out near Venus’ orbit before plunging in close to Mercury’s orbit. This isn’t the most stable way for a large rock to orbit, and scientists suspect that gravitational tugs from Mercury and Venus will eventually send this object careening into one of these two dead surfaces. In fact, this could be the fate for most objects that end up in this kind of an object… so now the questions are, how many of these objects are out there, and how cool would it be to get to see a 1-3 km object smack into an unoccupied inner planet.

You can read the press release at:

First Asteroid Found Inside Orbit of Venus (Caltech)