The Sky Tonight: Mercury at Greatest Western Elongation

mercury at greatest western elongation

The planet Mercury reaches greatest western elongation of 27 degrees from the Sun. This is the best time to view Mercury since it will be at its highest point above the horizon in the morning sky. Look for the planet low in the eastern sky just before sunrise.

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It’s the First Day of Spring

march equinox

The March equinox occurs at 16:15 UTC. The Sun will shine directly on the equator and there will be nearly equal amounts of day and night throughout the world. This is also the first day of spring (vernal equinox) in the Northern Hemisphere and the first day of fall (autumnal equinox) in the Southern Hemisphere.

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The First Confirmed Extragalactic Planets


On January 9 1992, two planets orbiting the pulsar PSR 1257+12 had been confirmed.  This is generally considered to be the first definitive detection of planets beyond our own solar system.  And now, as of February 1 2018, planets beyond our own galaxy have been confirmed. 

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The Sky Tonight Update: Full Moon, Super Moon, Blue Moon

full moon, super moon, blue moon

This January 31st, the Moon will be located on the opposite side of the Earth as the Sun and its face will be will be fully illuminated.  Since this is the second full moon in the same month, it is sometimes referred to as a blue moon. This is also the last of two supermoons for 2018. The Moon will be at its closest approach to the Earth and may look slightly larger and brighter than usual.