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Bruce McClure

Know the Big and Little Dippers

The Big Dipper is easy. And, once you find it, you can find the Little Dipper, too. Plus … learn how the stars of the Big Dipper are moving in space.

A mysterious star called Epsilon Aurigae

Epsilon Aurigae’s light dims for a period of about 2 years, in a 27-year cycle. The star’s last dimming was from 2009 to 2011.

Venus after sunset and before sunrise!

The planet Venus is now appearing in the west after sunset and in the east before sunrise. Don’t believe it? Astronomer Bruce McClure reports on his observation.

What is stellar magnitude?

Brightest stars to the eye are 1st magnitude, and dimmest stars to the naked eye are 6th magnitude. How the magnitude scale works in astronomy and why it’s useful.

Is Sirius the most luminous star?

To astronomers, the word “luminous” refers to a star’s intrinsic brightness. Sirius is our sky’s brightest star, but only because it’s relatively nearby at 8.6 light-years away.

Arcturus, a northern springtime star

Orange Arcturus is the constellation Bootes the Herdsman’s brightest star. Look for it in the east around nightfall.

Watch the sun’s shift on your horizon

Here’s a fun activity for the coming months. Note how far the sun moves on your horizon each day, as spring shifts toward summer (or autumn towards winter).

Equinox sun rises due east, sets due west

How can the sun rise due east and set due west – for all of us – on the day of the March equinox? Explanation, charts, diagrams, here.

Equal day and night on equinox?

The sun is a disk, not a point of light. Plus Earth’s atmosphere refracts sunlight. For both reasons, we have more than 12 hours of daylight on the day of an equinox.

Fastest sunsets near equinoxes

We’re talking about the amount of time needed for the body of the sun to sink below the horizon. It’s true. The sun actually sets faster around the time of an equinox.