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Mercury and the moon get close on the morning of September 29! They’re easiest to see from the Northern Hemisphere or southern tropics.

September 28 is also the day of Mercury’s greatest elongation, when the planet will be 18 degrees west of the sun on our sky’s dome. Look shortly before sunup.

Everyone around the world can see the moon and Regulus these next 2 mornings. From the Northern Hemisphere, you might also see Mercury.

Many use the constellation Cassiopedia – which is easy to find, shaped like an M or W – as a jumping off point for locating the Andromeda galaxy.

Enjoy the moon and Gemini stars, Castor and Pollux, as the moon makes its monthly journey through the zodiacal constellation Gemini the Twins over the next few days.

It’s often said that – at each equinox – the sun rises due east and sets due west. And that’s true. But why? How can you conceptualize this?

At tomorrow’s equinox, the midday sun will be straight overhead seen from Earth’s equator. The sun will be crossing the sky’s equator, going north to south.

Use the waning moon to find Aldebaran, brightest star in Taurus, and the Pleiades star cluster. Plus info on the occultation of Aldebaran by the moon.

The sun sinks below the horizon faster around the September and March equinoxes than at any other time.

Go outside around mid-evening – and learn to keep the loneliest star company.

Although we’re past full moon now, the moon is still big and bright. Also, watch each morning in the west for a pale daytime moon floating against a blue sky.