Skywatcher’s guide all the planets set summer’s stage – longmont times-call electric utility companies charge customers for


The top story is the arrival of the Summer Solstice at 4:07 a.m. June 21 (MDT), the moment when the sun is farthest north in the celestial sphere. That day is 15 hours, 1 minute in duration, the longest day. Because of the Earth’s 23 ½-degree axis tilt, the earliest sunrise is at 5:31 a.m. June 14, the latest sunset 8:34 p.m. June 27.

Although the days are technically getting shorter after the 21st, most of the daylight’s loss is on the morning side before 6 a.m. The halcyon days and warm evenings are long; we lose only about 6 minutes on the sunset side by July 15, and only 40 minutes of total daylight by the 31st. The solstice isn’t to blame for cutting short your youth and summer fun; better to check the hot, desiccated pockets of August for the theft of more than 70 minutes of daylength.

Summer’s arrival is ballyhooed by a balustrade of all the officially recognized planets of the solar system, the moon and a naked eye asteroid. Planets were to the Ancient Greeks deities and "planetes," or "wanderers" because they often do not move in concert with the other stars in the sky.

Even before the sun sets, Venus is high in the west-northwest in Constellation Gemini, "the twins Castor and Pollux," brightening to magnitude -4.1 as a prominent evening star all month. Standing at nearly 28 degrees above the horizon, the highest of the year for sunset viewers, the carbon dioxide-shrouded orb sets more than 2½ hours after nightfall. On nights of June 19 to 20, watch for Venus to move within shouting distance of the Beehive Cluster in the dim Constellation Cancer, "the scarab" to the Ancient Egyptians of 2000 B.C.

Jupiter, coming off its May opposition, is also already high above the horizon — albeit in the east — drifting nightly into Constellation Libra, "the scales of justice," as night enshrouds the land. This June offers premium Jupiter viewing as it reaches its highest point at 11 p.m. at the beginning of the month, hitting the meridian as early as 9 p.m. on the 30th. Impressive on its own without optical aid in a verdant, quiet field, the Jovian giant’s four Galilean moons — Ganymede, Io, Callisto and Europa — are visible with even the smallest of astronomical instruments.

This month is also a prime month for viewing Saturn, which reaches opposition overnight June 26 to 27. The gas giant is not only at its closest, biggest in telescopes and brightest for the year, but also is so positioned that its rings are tilted at 27 degree open, nearly the maximum possible from our line of sight. Witness the full moon and Saturn to come within 1 degree of one another June 26 to 28.

This is a great time to examine the rings, their gaps, the 62 named moons and the nine more awaiting designation, the polar caps, etc. Keep in mind, however, that this Saturnian opposition finds Chronos dwelling low in the southern comfort of the Teapot of Sagittarius, where the laminae of the atmosphere offers more turbulent seeing.

If you’ve never seen an asteroid, now is your chance. Vesta 4 reflects sunlight at magnitude 5.3, so it is comfortably bright enough to see with the naked eye in reasonably dark skies. Vesta 4, a 326-diameter rock designated as a minor planet, is the brightest and second-most massive object in the asteroid belt that lies between the orbits of Mars and Jupiter. It is uniquely differentiated among its brethren, that is to say, it has a crust, mantle and core more like earth than other asteroids. Given its low position, best views are through a telescope.