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Star Trak: July 2018

For Immediate Release Jun 29, 2018

BLOOMINGTON, Ind. – This summer will be the best time to view Mars. The Red Planet won’t be as well placed again for observers until 2035.

In early July, Mars will rise about two hours after sunset and be highest in the south around 3 a.m., brighter than any other object except the moon and Venus. Mars will reach opposition on the night of July 26-27 and come closest to Earth on July 30-31. By month’s end it will rise around sunset and peak in the south shortly before 1 a.m. Mars will spend the month among the stars of the constellation Capricornus, more than 100 times brighter than any of those stars and almost twice as bright as Jupiter.

Jupiter will appear high in the south soon after sunset in early July. The giant planet will fade somewhat as the month passes, but it will continue to be a fine sight in telescopes of all sizes.

This summer will be the best time to view Mars until 2035.Photo courtesy of NASA/USGS

Saturn will shine less brightly than Jupiter during July. At the start of the month it will be visible from dusk to dawn in the constellation Sagittarius. Saturn’s rings will be tilted 26 degrees to our line of sight, nearly their greatest possible tilt. The planet’s largest moon, Titan, will be visible with any telescope.

Venus will gleam fairly low in the west at nightfall in July, much brighter than Mars. About 45 minutes after sunset on July 9, the brilliant white planet will be joined by the bright white star Regulus about 1 degree to its lower left (south).

Mercury will come into view low in the west during evening twilight at the start of July. It will be about 15 degrees to the lower right (north) of Venus for the first half of the month, rapidly fading into the glow of twilight after that. On July 3 and 4, Mercury will be within 1 degree of the Beehive star cluster 45 minutes after sunset.

Lunar eclipse

Observers in most of Europe, Asia, Africa and Australia will see a total eclipse of the full moon on July 27. Totality will last 103 minutes, the longest since 2000.

Meteor shower

The Delta Aquarid meteor shower will peak before dawn on July 30, just three days after the full moon. In a dark sky, observers could expect to see about 25 meteors per hour, but this time they may have a better view before July 25.

The 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.


On July 6, 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.

Moon phases

The moon will be at third quarter on July 6, new on July 13, at first quarter on July 19 and full on July 27.

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