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Bruce McClure

Moon and star Regulus before dawn

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


Use Cassiopeia to find Andromeda galaxy

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.

Skywatcher, by Predrag Agatonovic.

Late September-October planet guide

Use the moon to catch Mercury before dawn in late September, 2016. Then watch as Jupiter pairs with Mercury in the picturesque glow of dawn on October 11.


Moon, Castor and Pollux before dawn

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.

Where does the celestial equator intersect your horizon?  No matter what you latitude is, it intersects your horizon at points due east and due west.  Read more about how an observer's latitude affects your visible sky.

Equinox sun rises due east, sets due west

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?

The day arc of the Sun, every hour, during the equinoxes as seen on the celestial dome, from the equator. Also showing 'twilight suns' down to -18° altitude. Note the Sun in the zenith at noon and that the tree's shadow is cast straight down, i.e. it stands in the center of its own shadow.  Image via Tau?olunga at Wikimedia Commons

Sun over Earth’s equator at equinox

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.

Relative to the backdrop stars of the zodiac, the moon moves an average 13o eastward per day. The green line depicts the ecliptic - the sun's annual path and the moon's approximate monthly path through the constellations.

Moon sweeps through Taurus the Bull

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.

Sunrise over Red Sea by Graham Telford

Year’s fastest sunsets around equinoxes

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

January 1, 2015 sunset by Helio de Carvalho Vital.  Shot 3 of 6.

Day and night exactly equal at equinoxes?

On the day of the equinox, the center of the sun would set about 12 hours after rising – given a level horizon, as at sea, and no atmospheric refraction.


How to find Fomalhaut, the loneliest star

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