EYES ON THE NIGHT SKY – JULY 2020
Welcome to the latest edition of Eyes on the Night Sky. The Summer Solstice is now behind us and the nights are still bright. For those living in the south of England, true darkness returns at the end of July, making the Milky Way, nebulae and galaxies easier to spot. Despite the lack of true darkness, we have some great targets to discover with the unaided eye, binoculars and telescope. Get out there and look up!
Spot Three Stars
You can still enjoy the silence and beauty of a deep twilight sky studded with bright stars – look out for the Summer Triangle comprising Deneb, Altair and Vega.
Shimmering Night Clouds
©Noctilucent Clouds by Sam Price
Nocilucent clouds can still be spotted in the northern sky, between 90 to 120 minutes after sunset and the same before sunrise throughout the month.
July is a great month for studying the planets. Mercury also is at Greatest Western Elongation on 22nd July, which means it rises about an hour and a half before sunrise, providing you with an opportunity to study the planet closest to the Sun. The diagram above illustrates what terminology such as Opposition and Great Eastern Elongation means. You can spot Mercury as a small, unblinking star the unaided eye, as planets don’t usually twinkle as much as stars.
Jupiter and Saturn take the main stage this month, with the middle of the month being the best time to study them. In the evening of 5th July, there will be a pleasing conjunction of the two planets plus the Full Moon, rising from the southeastern horizon. Watch them emerge into the sky when darkness starts to fall from 10pm onwards. On 14th July, Jupiter will reach opposition, the point where they will be closest to Earth, appearing to be brighter. Use a telescope to spot cloud bands and whorls, and watch the dance of Jupiter’s Moons, which can also be spotted as bright specks through binoculars. On 20th July, Saturn will also reach opposition. Use a telescope to study its rings and spot a few of its brighter moons.
Mars rises in the east at 11.45pm at the beginning of the month and around 10pm at the end. There’s a lovely conjunction of Mars and the Moon in its last quarter phase on 12th July – look to the east from 10pm and watch the two objects rise.
Venus heralds the morning sky with its beauty, rising in the Northeastern sky, rising at 2am at the start of the month and 1am at the end. Look out for the waning crescent Moon passing close to Venus on 17th July.
The Full Moon falls on 5th July and New Moon on 20th July. This Full Moon is also known as the Buck Moon, the time where antlers start to grow from the head of a male deer.
Constellation of the Month: Hercules
The constellation of Hercules is well placed in July, depicting a man kneeling with a club raised above his head. Look for the keystone asterism of this constellation and try to make out the arms and legs of this colourful character who featured in many myths. The Sumerians associated Hercules with the hero Gilgamesh and in Greek Mythology, he managed to complete multiple quests called the ‘Twelve labours of Hercules’, set by King Eurystheus of Tiryns, a character in Heracleidae, a play by Euripides. Notable quests included defeating the many headed beast called Hydra and Cancer the crab. Hercules was listed by 2nd Century Greek astronomer Ptolemy.
Two deep sky objects to note is the stunning Great Cluster in Hercules (M13) and M92, both globular clusters lying 22,180and 26,740 light years away respectively. M13 contains an amazing 300,000 stars and M92, around 330,000.
Despite M13 being much brighter, containing slightly less stars than its neighbour, it has double the radius and is closer to us. You can find these two clusters with binoculars, appearing as fuzzy objects and through a telescope, the stars will begin to be resolved.