As seen from the Americas tomorrow morning – Sunday, September 1 – the waning crescent moon will shine approximately midway between the planets Jupiter and Mars. Also, as seen from this part of the world, the moon will sit in between the Gemini stars, Castor and Pollux, and the Little Dog star, Procyon. Before dawn on September 1 in Europe, Africa, Asia, Australia and New Zealand, the waning crescent moon will shine somewhat closer to Jupiter and farther away from Mars.
From anywhere worldwide, Jupiter will be easy to see in the glow of dawn. That’s because this dazzling world is the second-brightest celestial body to light up the morning sky, after the moon. But you’ll probably have to get up before dawn, or perhaps as much as 90 minutes before sunrise, to spot the fainter planet Mars. At present, the king planet Jupiter beams a whopping 30 times more brilliantly than Mars does.
From anywhere worldwide, you can star-hop to Mars by way of the Gemini stars, Castor and Pollux. Castor more or less makes a right angle with Jupiter and Mars.
Jupiter is now about 2.5 times Mars’ distance from Earth. Nonetheless, Jupiter easily outshines Mars in Earth’s sky. As seen from Earth, Jupiter’s angular diameter spans 8 times that of Mars. Moreover, Jupiter’s cloud cover more effectively reflects sunlight than does the stark landscape of Mars. Jupiter reflects over 50% of the sunlight that hits its surface while Mars only reflects about 15%. All things considered, that makes Jupiter the brighter of these two worlds.
By the way, the Asteroid Belt lies in between the orbits of Mars and Jupiter. Mars, the fourth planet outward from the sun, is the most distant of the four terrestrial or rocky planets. In their order going outward from the sun, the inner rocky planets are Mercury, Venus, Earth and Mars. Jupiter, on the other hand, is the closest of the four outer gas giant planets: Jupiter, Saturn, Uranus and Neptune. Sometimes Uranus and Neptune are referred to as ice giants.
Bottom line: On the morning of September 1, 2013, use the waning crescent moon to find Mars, the outermost inner planet, and Jupiter, the innermost outer planet!