[ad_1]
The major celestial event of the summer is the closest approach to Mars since 2003. The red planet is now approaching the Earth at 338.00 km per day. In opposition (facing the sun as seen from Earth) on July 27, Mars will rise at sunset and set at sunrise, remaining visible all night long.
His closest approach to Earth, when it will be the largest telescope, occurs around 4:50 am on July 31.
When July opens, Mars (in the constellation Capricornus – sea goat) rises about two hours after sunset (one hour in the middle of the month) in the SE. Currently about mag. -2.2, Mars will double in brightness to a dazzling -2.8 by contrast. There is currently a global dust storm circulating the planet, which may or may not influence the views of the surface features of the planet and the southern ice sheet, if it persists to its closest approach of the Earth at the end of the month. More info on March this month, go to www.astronomy.com or www.skyandtelescope.com or google Mars July 2018.
As bright as Mars will be this month, it can not match the brilliance (magnitude -4.2) of Venus. Visible in the sky from the west to dusk about 45 minutes after sunset, Venus will follow the sun below the horizon shortly before midnight. Look for the 3 ½ day crescent moon to the right of Venus on July 15th.
If you're fast, you might spot Mercury this month. In the constellation of Cancer – the Crab, and shining to mag. At the beginning of July, Mercury reaches its greatest western elongation (angular distance from the Sun as seen from the Earth) on July 11th. Then, on July 14, a thin crescent moon is just above Mercury about 45 minutes after sunset. As of July 17, a dimmer (magnitude +1.0) Mercury is about 15 degrees lower right of Venus.
Jupiter is just south, just after sunset, in July, moving to the SW at the end of the month. Currently moving westward into the constellation Libra – the Ladders, Jupiter begins the month at mag. -2.3 before falling slightly to -2.1 at the end of July. A decent telescope will show the many cloud bands on the planet, the Great Red Spot and its four largest moons – Io, Europa, Callisto and Ganymede.
Saturn and its magnificent ring system, having reached the opposition on June 27, is still visible hours of darkness this month. At the mag. +0.0 (brightening slightly to +0.2 at the end of the month), Saturn is currently in the constellation Sagittarius – the Archer. Its best visibility (weather permitting) occurs when the planet is at its highest point in the night sky around midnight, when it crosses the meridian of the sky (facing south).
The Delta Aquarid meteor (radiant in Aquarius) peaks of rain in the hours before the dawn of July 28. Although the full moon will clean the weaker meteors, you should still be able to see a lot of 20 + / hour meteors as they cross the night sky in the summer.
next month, clear sky
Events (ADT):
July 6 – Last Quarter Moon
July 13 – New moon; perigee moon (closest to Earth)
July 19 – First quarter of the moon
July 27 – Full moon; moon at the apogee (farthest from Earth)
July 27 – March in opposition (visible all night)
July 28 – Delta Aquarid Meteorite Peak; pre-dawn
Glenn K. Roberts lives in Stratford, P.E.I., and has been an avid amateur astronomer since he was a small child. His column appears in The Guardian on the first Wednesday of each month. It welcomes readers' comments, and anyone wishing to do so is encouraged to send an email to [email protected]
[ad_2]
Source link
