2017, Late March: Venus as a Morning and an Evening Star

This is likely visible only with optical assistance, such as through binoculars or a small telescope.  WARNING!  NEVER POINT BINOCULARS OR TELESCOPE DIRECTLY AT THE SUN!   Such activity can cause permanent damage to your vision and/or the optical device.

As Venus rapidly disappears into the sun’s brightness during the next few weeks of March, it is visible in the morning sky and evening sky with optical assistance.  (Not to be redundant, but heed the warning above.)

Venus reaches inferior conjunction on March 25, 2017.  At this time Venus moves between the Earth and the sun.  Because the orbits  of the planets line nearly in a plane, but not a perfect one, Venus does not move directly across the face of the sun.  It either passes above or below the sun.

At this conjunction, Venus is about 8 degrees above or north of the sun.  When an object is north of the sun, it can appear in both the morning and evening sky.  The Big Dipper is far north of the sun.  In March, during the early evening from mid-northern latitudes, the Big Dipper appears to stand on its handle high in the northeast.  In the predawn hours, it appears to be dipping down from the northwestern sky.  The Big Dipper is an extreme case of the concept.  But is shows that anything north of the sun can be both seen in the morning sky and in the evening sky,

The chart above (click the image to see it larger), shows Venus’ invisible orbit at noon on inferior conjunction day.  With appropriate shading, the planet is visible with optical assistance.  It is north of the sun.

Starting at mid-March and until inferior conjunction, Venus rises just ahead of the sun in the morning and sets just after it in the evening, during bright twilight, and so the need for optical assistance.  The optimum date is March 22 when Venus rises about 30 minutes before the sun and sets 30 minutes after.

At 6:45 a.m. CDT in the Chicago are (check your local sunrise time for other locations), about 10 minutes before sunrise, Venus stands 4 degrees above the the horizon and about 11 degrees from the sunrise point.  A crescent moon is in the southeast, over 70 degrees from Venus and not much help with its identification.

That evening, about 15 minutes after sunset (7:10 p.m. CDT in the Chicago area), Venus is 4 degrees above the horizon and 8 degrees from the sunset point.  Dimmer Mercury is about 13 degrees to the upper left of Venus.

While not easily seen, it is possible to see Venus as both a morning and evening star.

For more information about current sky events, see these articles: