The Moon’s orbit (its circular path around the Earth) is indeed getting larger, at a rate of about 3.8 centimeters per year. (The Moon’s orbit has a radius of 384,000 km.) The reason for the increase is that the Moon raises tides on the Earth. Because the side of the Earth that faces the Moon [...]
As you probably know, our Sun is just a star. It’s our closest, most familiar star, but it’s still just a star. With a great big Universe out there, populated with countless stars, astronomers have been able to see examples of stars in all shapes, sizes, metal content and ages.According to their system of classification, [...]
The picture at left is the Scutum region seen in the summer sky. Click on the image to see at a larger size. The pinkish and brownish areas are the Milky Way, the edge of our galaxy. Scutum is a constellation. A constellation is a pattern of stars. When you look in the night sky [...]
The Great Orion Nebula in the sword of Orion is pictured at left. Stars are being formed in the cloud of gas and dust. Click on the image to see a larger version.
Gas, dust and debris from star explosions and around star forming regions are called nebulae. A nebula can reflect light (Reflection Nebulae) or [...]
