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Editors of EarthSky

Large and Small Magellanic Clouds shine in southern skies

Have you seen the Magellanic Clouds? These 2 satellite galaxies of the Milky Way are noticeable features in the skies of the Southern Hemisphere.

How high up are meteors when they begin to glow?

How high up are meteors when they begin to glow? Meteors begin to glow almost as soon as they hit Earth's atmosphere, but vaporize at varying altitudes.

Are Humberto and Imelda undergoing the Fujiwhara effect?

Humberto and Imelda are “crowding” the Atlantic basin. They are relatively near each other. Humberto appears to be exerting a “pull” on Imelda.

October birthstone: Colorful opal and tourmaline

Take your pick: the October birthstone is either the striking iridescent opal or the many-colored tourmaline. Learn the lore of these pretty gemstones here.

How many stars can you see on a moonless night?

Have you ever wondered how many stars are visible on a given night? It all depends on how dark your sky is, what your age is, and other limiting factors.

We have 4 seasons each year, but why?

Some assume our planet's changing distance from the sun causes the 4 seasons. But it's actually the tilt of the Earth's axis.

Radiant point of meteor showers: All you need to know

Meteors enter Earth's atmosphere on parallel paths. So, you'll see meteors appear to come from a single point in the sky: the radiant point!

Cassiopeia the Queen ascends in September and October

Cassiopeia the Queen is an easy-to-find constellation. It has the shape of a W or M. Look in the north-northeast sky on September and October evenings.
Astronomy Essentials

Saturn’s rings: Top tips for beginners

If you want to see Saturn's rings, September 2025 is a great time to look. Grab a telescope, find a dark sky and read the tips found here!

Sapphire: September birthstone comes in many colors

Sapphire, the September birthstone, is typically blue, the color caused by small amounts of titanium and iron in the crystal structure.

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