- Southern Hemisphere Sky Events

August 2011 Sky & Space Events

These notes are intended to provide a casual skywatcher or someone already into amateur astronomy living on the East Coast of Australia with a short summary of what is happening in the night sky in August 2011. Instructions on how to obtain customised satellite viewing information for your location can be found here. If you find this page of interest, you may wish to follow this website automatically using Twitter and the sites RSS Feed.

Planets this month (August 2011)

Mercury is visible low above the Western horizon during evening twilight at the start of August. It then moves back toward the Sun becoming invisible before moving into the morning twilight sky by the end of the month. Note that it will only be visible at the end of the month if you have an obstruction free horizon as it will be very low above the Eastern horizon as daylight begins.

Venus is not visible this month. It reappears in the evening sky in mid-September.

Mars is visible in the morning sky from around 4 am mid-month.

Jupiter rises around 11.30 pm mid-month. Look for a brilliant white star low on the Eastern horizon. With Venus not being visible this month, Jupiter is the brightest object in the night sky beside the Moon.

Saturn is visible in the early evening sky above the Western horizon for the entire month. Make the most of this month as it is the last for the year where Saturn will be high enough above the horizon for it to be worthwhile looking at through a telescope.

Uranus rises around 8.30pm AEST mid-month. It will require binoculars and a finder chart to locate. You will need at least a small telescope to resolve Uranus as being disc like (as opposed to point-like as a star appears in a small telescope).

Neptune reaches opposition this month on the 23rd, making this month and next the ideal time to view Neptune through a telescope. If you haven’t seen Neptune through a telescope, you are most likely to be disappointed with what you see. In spite of Neptune being so large that you could fit 50 Earths in it by volume, Neptune is so far from Earth that is reduced to looking like a tiny blue dot of light using a high powered eyepiece. I find that the only way for me to be sure I am looking at Neptune is to compare it to a nearby star. Neptune will barely appear as disc like as opposed to a point source of light for how the star appears.

 Individual sky events (August 2011)

All times listed for the AEST time zone (U.T. plus 10 hours).  Add one hour to times listed if your state or territory follows daylight savings time.

August 1: Ceres is stationary

August 1: Slim crescent Moon, Mercury and Regulus (the brightest star in the ancient Greek constellation Leo the Lion) make a temporary triangle low above the North West horizon during the evening twilight.

August 2: 5 pm Mercury is stationary.

August 3: 7 am Moon at perigee (closest to the Earth in its orbit at 365,761 km).

Moon and Saturn finder chart 7 pm 4 August 2011

August 4: Crescent Moon located to the left of Saturn. Early evening sky.

August 5: Vesta at opposition. This means that Vesta will rise as the Sun sets, and then set as the Sun rises the following morning. Opposition is also generally the time when a planet is at it’s closest in its orbit to the Earth. This makes it the best time to observe Vesta. Vesta will be easily visible in binoculars or a small telescope. If you have reasonably dark skies, Vesta is close enough to the Earth at this opposition to be visible to the unaided eye. You will need a suitable finder chart as it only reaches magnitude 5.6. This is the brightest approach until 2018 when it will reach magnitude 5.3 (magnitude 6 is considered the faintest that someone can see with the unaided eye). Some observers report noticing a slight reddish tinge when observing visually. Vesta is in the news at present with NASA’s Dawn robotic spacecraft recently arriving in orbit around Vesta. It is due to orbit Vesta for a year studying the asteroid at close range.

August 5: Crescent Moon located above Spica (the brightest star in the ancient Greek constellation Virgo the Virgin). Evening sky.

August 6: 9.08 pm First Quarter Moon

August 9: Venus at perihelion

August 9: Pluto will be 0.1 degree away from Y Sagittarii.

August 13: The Persid meteor shower peaks. This meteor shower is not visible from mid-Southern latitudes. I am mentioning it in this list because it is one of the Northern hemispheres best meteor showers and I get inquiries about this each year.

August 14: 4.57 am Full Moon

August 15: Mercury at greatest latitude South

August 16: Venus is at superior conjunction with the Sun.

August 17: Mercury at inferior conjunction with the Sun.

August 19: 2 am Moon at apogee (furthest from the Earth in its orbit at 405,161km).

August 21: Waning gibbous Moon located under Jupiter. Morning sky.

August 22: 7.54 am Last Quarter Moon

August 23: 9 am Neptune is at opposition.

August 26: Slim crescent Moon located to right of Mars. Morning pre-dawn sky.

August 26: 2 pm Mercury stationary

August 28: Very slim crescent Moon located above Mercury. Morning twilight sky. Look low above the Eastern horizon during the pre-dawn twilight. This will be very difficult given how close to ‘New’ the Moon will be. A clear horizon and a pair of binoculars will be required.

August 29: 1.04 pm New Moon

August 30: Venus at greatest latitude South

August 31: 3 am Jupiter stationary

August 31: 4 am Moon at perigee (closest to the Earth in its orbit at 360,858 km).

For Further Information

Planet and Moon Rise/Set Times

Planet and Moon rise/set times for 2011 can be found here on this website.

Customised Astronomy & Satellite Viewing information

Information on how to obtain customised astronomy & satellite viewing information for your location can be found here on this website.

About Josie Floyd

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1 thought on “August 2011 Sky & Space Events

  1. This is a great overview of the month’s events, Paul. Thanks so much! I’m just getting into astronomy and it looks like I’ll be visiting your site often 🙂 Thanks for all your hard work.

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