What’s up? Night sky for July 2011

Telescope inside a dome at night

Stargazing during winter is chilly, but the nights can often be crisp and clear. And there's plenty to see this month!

THE INNERMOST PLANET, Mercury, has delighted us in the morning sky for the past couple of months, but this month it makes a reappearance in our evening skies, in the west after sunset. It’ll be quite easy to see, above the horizon for around 100 minutes after the Sun sets at the beginning of the month, increasing to almost two-and-a-half hours after the Sun sets by the end of the month.

Also in the evening sky, to the north-west, is Saturn. The famous ringed planet will be on show during the first half of the night, setting around 11:00pm by the end of the month.

In the morning sky to the east, Jupiter and Mars are still putting on a show before sunrise.

Venus is too close to the Sun to be seen this month.

Except where indicated, all of the phenomena described here can be seen with the unaided eye. And unless otherwise specified, dates and times are for the Australian Eastern Standard Time zone, and sky directions are from the point of view of an observer in the Southern Hemisphere.

July 1

There will be a partial eclipse of the Sun today, but you’ll have to be an albatross or maybe a seal in order to see it. That’s because the Sun’s shadow will fall across a remote area of ocean between South Africa and Antarctica. Unless there are some fishing boats or a scientific expedition in the area, it’s entirely possible that no one will witness this eclipse which, at its maximum, will see less than 10% of the Sun’s disc covered by the Moon. And speaking of the Moon, New Moon occurs today at 6:54pm Sydney time (08:54 Universal Time).


View of the night sky for July 3, 2011

July 3, 2011, 5:15pm: The thin crescent Moon will sit just above the planet Mercury in the western sky after sunset.


July 3

Take a look out to the west after sunset, and you should see the planet Mercury above the horizon, and above it will be the thin crescent Moon.

July 5

Earth reaches aphelion today (or July 4 in the western hemisphere), which is the farthest point from the Sun in our orbit. The distance between Earth and Sun will be 152.1 million kilometres.

There’ll be an interesting sight out to the east in the morning sky today. The planet Mars will appear close to the star Aldebaran. Both are of similar brightness, and both have similar colouring—a sort of orangey-red.

In this evening’s sky, the Moon will sit above the bright star Regulus. Regulus is the brightest star in the constellation Leo. The amazing thing about Regulus is that, although to the naked eye it appears to be one star, in reality it is composed of four stars grouped into two pairs, all gravitationally bound to each other! This sort of thing is not too uncommon—many other stars are members of double, triple or quadruple systems too.

Position of the Moon, Spica and Saturn on July 8, 2011

July 8, 2011, 7:15pm: The Moon will be bracketed by the planet Saturn and the star Spica, in the north-western sky.



July 8

It is First Quarter Moon today at 4:29pm Sydney time (06:29 Universal Time). First Quarter is a good time to look at the Moon through a telescope, as the sunlight angle means the craters and mountains throw nice shadows, making it easier to get that 3D effect. Also today, the Moon will be at the closest point to Earth in its orbit, called perigee, at 12:05am (14:05 on July 7, Universal Time). The distance between the two bodies will be 369,565 kilometres. And finally, tonight the Moon will appear reasonably near the planet Saturn.

July 9

A little more than half full, the Moon will appear quite close to the star Spica tonight. Spica, a blue giant star, is the brightest star in the constellation Virgo and the 15th-brightest star in our night sky.

Position of the Moon and Antares on July 12, 2011

July 12, 2011, 8:00pm: High in the northern sky, the Moon and the star Antares (the brightest star in the constellation Scorpius) will appear close together.



July 12

The now almost-full Moon will appear quite close to the star Antares tonight. Antares means “the rival of Mars’, and it’s not hard to see why, as it’s ruddy colour makes it look just like the fourth planet from the Sun. Antares is a red supergiant star, 800 times bigger than the Sun!

Today, the eighth planet from the Sun, Neptune, has completed one full orbit of the Sun since its discovery in 1846. Neptune takes almost 165 years to complete one circuit of the Sun. Neptune is too faint to be seen with the naked eye, but it is within the range of medium-and-larger backyard telescopes, if you know exactly where to look. This chart, provided by the Royal Astronomical Society of New Zealand, will help you to find it.

July 15

Full Moon occurs today at 4:40pm Sydney time (06:40 Universal Time).

July 20

Mercury reaches its greatest angle from the Sun today, so if you have a clear evening sky, why not take the opportunity to go out and spot it in the west after sunset?

Position of Mercury on July 20, 2011

July 20, 2011, 5:20pm: Mercury will be at its greatest angle from the Sun today, and visible in the west after sunset.

July 22

Today the Moon will reach the farthest point in its orbit around the Earth, called apogee, at a distance of 404,356 kilometres at 8:48am Sydney time (22:48 on July 21, Universal Time).

July 23

It is Last Quarter Moon today at 3:02pm Sydney time (05:02 Universal Time).

July 24

Slightly less than half full, the Moon will appear close to the planet Jupiter in this morning’s sky. Jupiter will be about 12 Moon widths above the Moon. Look a little further east and you’ll see Mars too. In between will be the beautiful star cluster called the Pleiades, also known as the Seven Sisters. Use binoculars or a small telescope and you’ll be delighted with the view.

Position of the Moon, Jupiter and Mars on July 24, 2011

July 24, 2011, 6:20am: The Moon and two planets—Jupiter and Mars—will be visible in the north-eastern sky before sunrise. See if you can spot the Pleiades star cluster as well.

July 25-28

In the western sky after sunset, the planet Mercury will appear close to the star Regulus (see July 5 for more information on this star).

July 28

The crescent Moon will appear very close to the planet Mars in this morning’s sky. They’ll be separated by only three Moon widths.

July 31

New Moon occurs today at 4:40am Sydney time (18:40 on July 30, Universal Time).

If you have any questions or comments on the night sky, we’d be happy to answer them. Please use the Feedback Form below. Happy stargazing!

Images courtesy IAU.

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  1. Jonathan Nally says:

    Glad you like it Michelle.

  2. Michelle Couch says:

    What an interesting, informative and comprehensible site! Thanks