Last modified: Thursday, June 28, 2007
STAR TRAK
Venus and Saturn start July together, then move apart
Photo by: NASA
Venus
FOR IMMEDIATE RELEASE
June 28, 2007
BLOOMINGTON, Ind. -- The planets Venus and Saturn will be very close in the western sky as darkness falls on July 1, with Saturn slightly higher. The bright star Regulus in the constellation Leo the Lion will be nearby to the left (south).
Venus will be so much brighter than either Saturn or Regulus that at first you may see only one brilliant white object completely dominating the sky in the west. Venus will be 100 times brighter than Saturn, which in turn will be twice as bright as Regulus. Binoculars will give a spectacular view of all three.
Venus has been outshining everything except the moon since February, but its long evening show is about to end. Each night during July it will appear lower in the sky and set earlier.
Saturn will fall even faster, pulling away from Venus as Venus approaches Regulus. Saturn will be lost in the sun's glow by month's end, appearing in the morning sky later in the year for another rendezvous with Venus.
Venus and Regulus will be closest on the evenings of July 12-13, but look for them early in twilight, before they sink from view.
Jupiter will gleam brightly in the south at nightfall during July, with the orange star Antares in the constellation Scorpius beneath it. Jupiter will be lower than usual, however, so the view through a telescope will be best in early evening, when Earth's atmosphere is steady. As the evening advances, both Jupiter and Antares will move lower in the southwest.
Slowly but surely, Mars is becoming more visible in the morning sky. The red-orange planet will rise in the east-northeast around 2 a.m. local time at the beginning of the month and an hour earlier by month's end.
Mercury will make one of its best morning appearances of the year in the latter half of the month, reaching its greatest distance from the sun on July 20. Binoculars will help you find the small planet in the glow above the east-northeastern horizon a half hour before sunrise.
Earth will reach its farthest distance from the sun for the year, called aphelion, on July 6. Believe it or not, we'll be about 3 percent farther from the sun than we were in January.
Viewing information and graphics for the planets are available at https://www.space.com/spacewatch/.
Noctilucent clouds
A beautiful phenomenon of the twilight sky called noctilucent clouds is sometimes visible in the Northern Hemisphere during summer. These wispy clouds form when water vapor condenses onto meteoric dust particles about 50 miles above Earth's surface. Noctilucent clouds are so thin that they are invisible in daylight. They can be seen only when the sun is just below the horizon, either in the northwest after sunset or in the northeast before sunrise, when the background sky is dark enough but there is still some light. Look for delicate bluish-white veils above the place where the sun is below the horizon. They are easy to distinguish from regular clouds, which appear dark against the morning or evening twilight. Numerous photographs of noctilucent clouds can be seen at https://www.polarx.net/NoctilucentClouds.htm.
Meteor shower
The southern branch of the Delta Aquarid meteor shower will peak before dawn on July 28, with meteors appearing several nights before and after the peak as well. The long, bright streaks will seem to come from a point in the constellation Aquarius in the southern sky during the hours just before morning twilight. In a dark sky there might be as many as 20 meteors per hour at the peak, but this year the full moon will wash out all but the brightest meteors.
Moon phases
The moon will be at third quarter on July 7, new on July 14, at first quarter on July 22 and full on July 29.
