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Star Trak: July 2020

For immediate release: July 1, 2020

BLOOMINGTON, Ind. -- Jupiter and Saturn will offer fine views from dusk to dawn during July. Both giant planets will be opposite the sun in our sky, rising in the southeast within an hour of sunset.

In early July, Jupiter and Saturn will be highest in the south at 2:00 a.m. and 2:30 a.m. local daylight time, respectively, and around 11:45 p.m. and 12:15 a.m. at month's end. By late July the two planets will set well before sunrise.

Jupiter will reach opposition on July 14, appearing in the eastern part of the constellation Sagittarius. The planet will be a fine sight in telescopes, and its four Galilean moons will shine at their brightest.

Bright yellow Saturn will be at opposition on July 20. The planet's rings will be tilted 21 degrees toward us. Its largest moon, Titan, will be visible with any telescope. Titan will be due north of Saturn on July 15 and 31 and due south on July 7 and 23.

Mars will dramatically increase in brightness during July. It will rise around 12:30 a.m. local daylight time at the start of the month and shortly after 11 p.m. by month's end. It will appear larger as the distance between Earth and Mars decreases.

Venus will shoot upward from morning twilight during July for observers at mid-northern latitudes. The planet's sunrise altitude will leap from 21 degrees to 35 degrees above the eastern horizon, the biggest monthly increase in its eight-year cycle of appearances. Its brilliance will make it easy to see with the naked eye at sunrise. An hour before sunrise on July 12, Venus will pass 1 degree north of the bright orange star Aldebaran in the constellation Taurus.

Mercury will emerge from the solar glare into the dawn sky around July 17, when it will rise about an hour before the sun. Its visibility will improve as the month passes, and on July 31 it will form a triangle with the bright stars Pollux and Castor in the constellation Gemini above the east-northeastern horizon.

Meteor Shower

The Delta Aquariid meteor shower will peak before dawn on July 29. In a dark sky observers may see as many as 20 meteors per hour. Some meteors will appear from mid-July to mid-August. The long bright streaks will seem to come from a point in the constellation Aquarius in the southern sky.

Aphelion

On July 4, Earth will reach its greatest distance from the sun for the year, called aphelion. Those sweltering in summer heat in the Northern Hemisphere may find it hard to believe they are about 3 percent farther from the sun than they were in January. But the actual cause of the high temperatures is the tilt of Earth's axis. The part of the planet tilted toward the sun (in this case the Northern Hemisphere) is much warmer than the part tilted away, because more sunlight reaches the ground instead of being absorbed by the atmosphere.

Full MoonFull Moon
Photo Credit: JPL NASA

Moon phases

The moon will be full on July 5, at third quarter on July 12, new on July 20 and at first quarter on July 27.

Author: Hal Kibbey Email: hkibbey [at] gmail.com

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