The White Bunny

On February 2, 2004, JPL released a panoramic image of the martian surface as seen by Opportunity. It's a remarkable image, showing a rock outcropping, the dusty surface, the imprints of the airbags, and other interesting features.

If you download the medium or big image, and look about halfway down and two-thirds of the way to the right, you'll see an unusual-looking object sitting on its own, several meters from anything else. It's whitish, and clearly not a rock. It has two prongs sticking up, looking very much like a rabbit head.

I'll admit this is a pretty weird thing. But when the pseudoscientist community got a hold of it, speculation ran rampant. The object was quickly dubbed "the bunny", and people wondered if it could be a fossil, an animal, or an artifact.

A few days later, the Opportunity rover left its lander and started roving across Mars. In images returned after that, it looked like Opportunity had run over the "bunny"! Worse, Opportunity had made a little side excursion while moving, making it look like NASA had run over the object on purpose. Was NASA trying to cover up the existence of an alien?

Hoagland, of course, had to pipe up about this, so he put up a picture on his site claiming that the object was "optically removed" by NASA from later images, and the "bunny" had been run over twice by the rover.

Given that I am making a case that people are letting themselves get carried away with too little information, you can imagine I am not as easily swayed that this is evidence of an alien, and a NASA coverup. So what's really going on?

Luckily, cooler (and more rational) heads at JPL looked into this. They found that the bunny is most likely a piece of the lander that broke off on impact. The object appears to move in a light wind, so it's not rock or metal, and must be soft. There are lots of soft materials on the lander, including the airbags used to protect the lander while it bounced to a stop on the surface of Mars. The JPL crew looked at the object in images showing different colors, and the color of the object looks much more like something from the lander than from the surface of Mars itself (most things sitting on the surface of Mars are covered in dust). Remember too that it was sitting all by itself in the middle of undisturbed ground, while rocks tend to cluster together in images.

The people analyzing the images at JPL also noticed that the object appears to move in the wind. That is consistent with it being something lightweight, like an airbag (note that the shadow doesn't appear to move in those images when one of the "ears" is twitching, but it looks to me that the "ear" is moving toward and away from the Sun, so the shadow wouldn't move much).

But then why is the "bunny" gone in later images? Did the rover run over it, crushing it, or did NASA digitally remove it, as Hoagland claims?

First, I have looked at the images, and I'd say that when the rover moved off the lander, it does look to me like it moved toward where the "bunny" was sitting. The images of the rover tracks do also show a white spot under the tread marks as well. But this does not mean the rover ran over the "bunny"!

The bright spot under the treads looks far more like what is called a "specular reflection" to me. Compacted sand reflects light differently than loose sand. You've probably seen this on the beach yourself; if you look at the shadow of your head in the sand, it appears to have a bright glow or halo around it. This is called "heiligenschein", which is German for "halo". This is a pretty common effect, and can even be seen in Apollo images of the Moon!

On the Bad Astronomy Bulletin Board, regular poster Ian Goddard notes this, and also points out several other images showing this reflection in rover tread marks. So tread marks with whitish glow does not mean they run over an object.

Furthermore, remember that the object was lightweight, and could be moved by a light wind. This would then simply explain why it isn't in later images. Instead of being digitally removed, as Hoagland claims, it is far more likely it simply blew away in the martian wind. In fact, the JPL folks may have spotted it underneath the lander, blown there by the wind. I cannot tell if that is the "bunny" for sure or not, but it was not in earlier images, and it's about the right size. Either way, it's a far more likely explanation than a fuzzy alien bunny (well, metaphorically) hopping around Mars.

Also remember that, as usual, conspiracy theories generally collapse under their own weight. In this case, why would NASA run over the "bunny" after it had been spotted, when NASA knows the images are made public immediately? If they would go to the trouble to digitally remove it from later images, then why didn't they remove it from the first one before it was released? Remember, Hoagland claims that NASA has been covering up evidence of aliens for years; it seems logical that if he were right, NASA would be scrutinizing every picture before they release it. This is a huge self-contradiction in Hoagland's claims.

And, if NASA were removing the "bunny" from the images digitally, why crush it with the rover? That makes it harder to remove, since the treadmarks make a more complicated background than the smooth martian surface.

So typically, if you spend a moment thinking about Hoagland's claims, you'll realize they're pretty silly. I find it remarkable that so many people would jump to the conclusion that the "bunny" was some sort of evidence of alien life. After all, the only sign of intelligent life there on Mars is... the rover itself! So it seems far more likely that anything really weird and out-of-place on the martian surface would come from the one thing we know is out-of-place there: the rover.