The instant I saw the avalanche image from the HiRISE camera on-board MRO orbiting Mars, I knew I would have a contender for my Top Ten Astronomy Pictures of 2008.
But then they released this one at the same time:
Yeah, that’s us. That’s home. We were 192 million kilometers (115 million miles) from Mars when HiRISE turned around and took this picture. Right away I could tell that was South America’s west coastline… which is incredible. I also was just starting to wonder about the Moon in the image when I read that it had been brightened artificially to make it easier to see; in general the Earth is 3-4 times more reflective than the Moon, so it’s a lot brighter.
The Mars-Earth-Sun angle was just about 90 degrees when this was taken, which is why the Earth and Moon are half-full. Note that in reality, the Moon is about 30 Earth-diameters away from the Earth, so we’re seeing some perspective here. The Moon was a day before third quarter when this was taken, so it was actually a bit closer to Mars than the Earth was when HiRISE snapped this picture.
Beautiful.
Cool find. Considering the fact that only 20 years ago such technological advances would never have been thought to be achieved so early. Nice work.
ReplyDelete