Star chart courtesy of the Society for Popular Astronomy

There is a new moon on July 1, first quarter occurs on the eighth, full moon on the 15th, last quarter on the 23rd and a new moon on the 30th.

On July 3, using binoculars, a crescent moon can be seen to the left of the planet Mercury in the twilight sky. On July 7 the moon lies below the ringed planet Saturn. On July 8, the first quarter moon passes the star Spica in the constellation of Virgo.

On July 11 and 12 the moon is close to the star Antares in the constellation of Scorpius. On the morning of July 24 the moon is directly above the giant planet Jupiter. A crescent moon can be found close to the red planet Mars on the mornings of July 27 and 28.

On July 4 the Earth is at aphelion, the point in our home planet’s elliptical orbit when it is furthest from the Sun; at this time the Earth will be about 152 million km from the Sun. We experience summer in the northern hemisphere at this time as the north pole is tilted 23.45° towards the Sun.

• The Society for Popular Astronomy – click here

• The Shropshire Astronomical Society – click here

Mercury, closest planet to the Sun, is just visible low in the north west at about 10.30pm during the first week of July. The planet Saturn is resplendent all evening in the constellation of Virgo, close to the star Porrima, but sets around midnight.

Neptune is the outermost of the four giant planets. It rises at about 10.30pm and can be found with the aid of a telescope in the constellation of Aquarius.

The planet Uranus, located in the constellation of Pisces, rises at about 11.30pm and is just visible with the naked eye.

The planet Jupiter rises about 1am within the constellation of Aries and is the brightest object in July’s night sky after the moon. The red planet Mars rises at about 2am and may just be visible low in the north east before dawn breaks.

Three brilliant stars, Vega, Deneb and Altair, form the asterism of the Summer Triangle. Deneb, an Arabic name meaning ‘The tail of the Swan’, is the brightest star in the constellation of Cygnus (the Northern Cross). It is a very hot, blue-white, supergiant star, the 19th brightest in the night sky and very distant at about 3000 light years from Earth. Deneb is over 200 times the diameter of our Sun and about 200,000 times more luminous.

Vega is the only bright star in the constellation of Lyra and is a little over 25 light years from Earth. The name Vega derives from the Arabic for ‘swooping eagle’; it is the fifth brightest star in the heavens and due to the precession of the equinoxes will be the Pole Star 14,000 years hence.

Altair in the constellation of Aquila, The Eagle, is the 11th brightest star in the night sky. The name Altair is from the Arabic for ‘flying eagle’ and at a distance of about 16 light years it is relatively close to Earth. Altair has a high rate of axial spin with a rotational period of about 6.5 hours (compared to about 30 days for our Sun), this produces a diameter at its equator that is at least 14 per cent greater than at its poles.

July is a good month to explore the southerly constellations of Scorpius and Sagittarius located within the Milky Way.

Use binoculars to scan Sagittarius for the star clusters M22 and M24, the Omega Nebula and the Lagoon Nebula.

Ron Iremonger