I’m on the Space Weather News mailing list. One message per day brings news of what’s going on in our corner of the universe. Today the website has images from Mars brought by NASA’s six-wheeled rover Spirit. It also tells us:
Earth’s orbit around the sun isn’t a perfect circle, it’s an ellipse. One side is closer to the sun (147.5 million km) than the other (152.6 million km). Today, January 4th, we’re at the closest point, known to astronomers as perihelion. The sun looks a bit bigger than average and sunlight falling on Earth is a few percent more intense.