Earth Sky News for Jan. 17th:

Venus, brightest of four morning planets

The planet Venus, the most brilliant star-like object in all the heavens, lights up the southeast sky in the wee morning hours. Get up at least 75 minutes before sunrise – or better yet, 90 minutes before. Then you can use Venus to find the great line-up of planets stringing across in the January 2016 morning sky. The other three visible planets are found to the west of Venus in this order: Saturn, Mars and Jupiter.

Saturn is by far the closest planet to Venus right now. You can distinguish Saturn from the nearby star Antares by color. Saturn, the brighter of the two star-like lights, exhibits a golden hue while Antares displays a ruddy complexion. If you have difficulty distinguishing color, try binoculars.

Once you have Venus and Saturn firmly identified, go on from there to locate Mars and Jupiter. All the planets line up very nicely, forming a well-defined arc across the sky. That’s because the planets are always found on or near the ecliptic – the Earth’s orbital plane projected outward onto the constellations of the Zodiac.

Possibly, you could mistake the star Spica for Mars. As with Saturn and Antares, you can tell the difference between Spica and Mars by color. Spica radiates blue-white while Mars glowers red.

Later on this month, the planet Mercury will climb high enough from the glare of sunrise to join this parade of planets. Eagle-eyed observers might see Mercury as early as January 20. However, Mercury will be quite dim, and at mid-northern latitudes, only rising an hour or so before sunrise on that date.

More realistically, most people will probably first see Mercury, the innermost planet of the solar system, around January 25, when Mercury will be both brighter and rising earlier (about 80 minutes before sunrise). Remember to draw an imaginary line from Saturn through Venus to locate Mercury near the sunrise point on the horizon.

Bottom line: Let Venus and Saturn escort you to Mars and Jupiter for a good month to come. Then let Saturn and Venus also guide you to Mercury, the solar system’s innermost planet, during the last week of January and the first few weeks of February.

 

Author

Bruce McClure