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Gallery – Geyser moon seen in silhouette

Saturn's moon Enceladus

Saturn's moon Enceladus appears in silhouette in this image taken by NASA's Cassini spacecraft. The bulk of Saturn is in the background, the planet's rings seen edge-on appear as the dark horizontal line.

NASA’S CASSINI SPACECRAFT took this image of Saturn’s moon Enceladus on October 19, 2011. As the spacecraft passed Enceladus, its infrared instruments, cameras and other instruments monitored activity on the moon, in particular the famed jets erupting from the its south pole. The orbiter flew within about 1,230 kilometres of Enceladus’ surface.

Although it appears dark in the silhouetted view, Enceladus, 504 kilometres wide, is actually one of the most reflective bodies in the Solar System because it is constantly coated by fresh, white particles of ice.

Also visible are Saturn’s rings, seen edge on.

More information:

Enceladus – Saturn’s shiny moon

The eruptions of Enceladus

Adapted from information issued by NASA/JPL-Caltech/Space Science Institute.

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Gallery – Quintet of Saturnian moons

Five of Saturn's moons

Five of Saturn's moons can be seen in this image taken by NASA's Cassini spacecraft.

A QUINTET OF SATURN’S MOONS can be seen in this view taken by the Cassini spacecraft.

Janus (179 kilometres wide) is on the far left. Pandora (81 kilometres) orbits between the A ring and the thin F ring near the middle of the image. Brightly reflective Enceladus (504 kilometres) appears above the centre of the image. Saturn’s second largest moon, Rhea (1,528 kilometres), is bisected by the right edge of the image. The smaller moon Mimas (396 kilometres) can be seen beyond Rhea also on the right side of the image.

This view looks toward the northern, sunlit side of the rings from just above the ringplane. Rhea is closest to the camera. Saturn’s rings are beyond Rhea and Mimas. Enceladus also is beyond the rings.

The image was taken with the Cassini spacecraft narrow-angle camera on July 29, 2011. The view was acquired at a distance of approximately 1.1 million kilometres from Rhea and 1.8 million kilometres from Enceladus.

Adapted from information issued by NASA / JPL-Caltech / Space Science Institute.

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Gallery – Dione and friends

Saturn's moon Dione

Saturn's moon Dione, seen along with half of Saturn and the planets rings.

SATURN’S MOON DIONE coasts along in its orbit appearing in front of its parent planet in this Cassini spacecraft view.

The wispy terrain on the trailing hemisphere of Dione (1,123 kilometres wide) can be seen on the left of the moon here.

Dione (pronounced dy-OH-nee) is the second densest moon of Saturn, after Titan. Dione is probably composed of a rocky core making up one-third of the moon’s mass, and the rest is composed of water ice. It is similar to two other Saturnian moons, Tethys and Rhea.

Dione’s icy surface includes heavily cratered terrain, with moderately and lightly cratered plains, as well as some severely cracked areas, with very bright material on the walls of the fractures. The heavily cratered terrain has numerous craters greater than 100 kilometres in diameter. The plains area tends to have craters less than 30 kilometres in diameter.

Telesto and Epimetheus

The moon Telesto can be seen above the rings on the left, and Epimetheus is just on the bottom edge of the rings.

The tiny moon Telesto (25 kilometres wide) is visible as a white speck above and to the left of the rings in this view. Epimetheus (113 kilometres) appears just below the rings near the centre of the image. This view looks toward the northern, sunlit side of the rings from just above the ringplane.

The image was taken with the Cassini spacecraft narrow-angle camera on July 18, 2011. The view was acquired at a distance of approximately 2.2 million kilometres from Dione.

Adapted from information issued by NASA / JPL-Caltech / Space Science Institute.

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Gallery – Saturn’s four moon shuffle

Cassini image of four Saturnian moons

Four of Saturn's moons are visible in the image taken by NASA's Cassini spacecraft.

A QUARTET OF SATURN’S MOONS, from tiny to huge, surround and are embedded within the planet’s rings in this Cassini image. Saturn itself is out of frame to the left.

Saturn’s largest moon, Titan (5,150 kilometres wide), is in the background of the image.

Next, in the foreground is Dione (1,123 kilometres wide), with the wispy terrain on its trailing hemisphere easily visible.

The third moon is Pandora(81 kilometres wide), which orbits just beyond the rings on the right of the image.

Saturn's rings with Pan in the  Encke gap

The tiny moon Pan appears as a speck in the gap in the rings.

Finally, tiny Pan (28 kilometres wide) can just be seen as a tiny speck in the ‘Encke Gap’ of the A ring on the left of the image.

Saturn has 62 known moons, with the vast majority of them being 50 kilometres or less in diameter.

The image was taken with the Cassini spacecraft narrow-angle camera on September 17, 2011, at a distance of approximately 2.1 million kilometres from Dione.

Adapted from information issued by NASA / JPL-Caltech / Space Science Institute.

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What’s up? Night sky for November 2011

People looking at the evening sky

Late spring nights and mornings are ideal for stargazing, and there are some interesting things to see 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.

November 3

It is First Quarter Moon today at 3:38am Australian Eastern Daylight Time. First Quarter is a good time to look at the Moon through a telescope, as the sunlight angle means the craters and mountains are throwing nice shadows, making it easier to get that 3D effect.

November 9

Take a look in the evening sky and you’ll see the Moon with what looks like a bright star above and to its right. Well, that’s not a star, it’s the planet Jupiter. Also today, the Moon will reach the farthest point from Earth in its orbit, apogee, at a distance from Earth of 406,176 kilometres.

November 10

Take a look at the western horizon after sunset and you’ll see a pretty group comprising Venus, Mercury and the star Antares.

Looking at the Moon with a telescope

The Moon teams up with several planets during November

November 11

Full Moon occurs today at 7:16am Australian Eastern Daylight Time.

November 11-12

Out to the east in the early morning sky (pre-dawn) you’ll find a pair of celestial orbs that contrast each other nicely in colour. Ruddy coloured Mars will appear very close to Regulus, a blue giant star that is the brightest star in the constellation Leo.

November 19

It is Last Quarter Moon today at 2:09am Australian Eastern Daylight Time. If you’re up before dawn, take a look out to the eastern sky and you’ll see the Moon with the star Regulus close by, and the planet Mars about 4 degrees away as well.

November 23

Another attractive grouping, but quite low in the eastern sky before dawn (so you’ll need a clear horizon). There’ll be the Moon, plus the star Spica (the brightest star in the constellation Virgo) and the planet Saturn as well.

November 24

Today the Moon will be at the closest point to Earth in its orbit, called perigee, which is the opposite of apogee. The distance between the two bodies today will be 359,691 kilometres.

November 25

New Moon occurs today at 5:10pm Australian Eastern Daylight Time.

November 27

Take a look out to the west just after sunset, and you might see the very thin crescent Moon below and to the right of the planet Venus.

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 / TWAN / Babak /A. Tafreshi.

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What’s up? Night sky for August 2011

Stargazers with telescopes

This month, Saturn will be the planet to watch in the western part of the sky after sunset.

FOUR PLANETS ARE VISIBLE THIS MONTH, although you’ll have to be quick to spot Mercury, as it starts the month low on the western horizon after sunset and within about a week will have become lost in the Sun’s glare.

Slightly higher in the western sky after sunset is Saturn, shining brightly and visited by the Moon on the 4th.

Jupiter and Mars are still the luminaries of the morning sky—Jupiter high in the north, and Mars low in the north-east. Their brighter sibling, Venus, will not be visible this month, as it is on the opposite side of the Sun from us.

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.

August 1

Look for the very thin crescent Moon low in the west after sunset. The planet Mercury will be about seven Moon widths above and to the right. Mercury is becoming much harder to see now, and over the next week will sink lower and lower toward the horizon and become lost in the Sun’s glare. The innermost planet will reappear in our morning sky out to the east next month.

August 3

Today the Moon will be at the closest point to Earth in its orbit, called perigee, at 7:00am. The distance between the two bodies will be 365,755 kilometres.

August 4

Look for the Moon and Saturn close together in the west in the early evening sky.

August 5

The Moon and the star Spica—the brightest star in the constellation Virgo—will appear close together tonight. The Moon will be about six Moon widths above the star.

August 6

It is First Quarter Moon today at 9:08pm. 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.

August 8

Now almost three-quarters full, the Moon will be near the star Antares—the brightest star in the constellation Scorpius. Antares has a reddish colour, and to the naked eye it looks a bit like the planet Mars. In fact, its name means ‘rival of Mars’.

Stargazers

Make the most of the late-winter nights by doing some stargazing.

August 14

Full Moon will occur today at 4:58am.

August 16

If you’ve been wondering why Venus doesn’t appear to be in our evening or morning skies, it’s because it is lost in the glare of the Sun. Today marks its ‘superior conjunction’, which means that it is on the exact opposite side of the Sun from us.

August 17

Mercury, which has been lost in the glare of the setting Sun for a while now, today reaches ‘inferior conjunction’, which means that it is exactly between us and the Sun. Mercury will reappear low in the east in the morning sky next month.

August 19

Today the Moon will be at the farthest point from Earth in its orbit, called apogee, at 2:24am. The distance between the two bodies will be 405,159 kilometres.

August 21

Look out to the east this morning, and you’ll see the Moon and what looks like a very bright star above and to its left. That’s not a star; it’s the planet Jupiter. Even if you don’t have a telescope, a normal pair of binoculars should reveal up to four of Jupiter’s largest moons, looking like small pinpricks of light to one or both sides of the planets.

August 22

It is Last Quarter Moon today at 9:55pm.

August 26

If you’re an early riser, take a look out to the east and you’ll see the Moon very close to the planet Mars.

August 29

New Moon occurs today at 1:04pm.

August 31

Today the Moon will again be at the closest point to Earth in its orbit, perigee, this time at 3:36am. The distance between the two bodies will be 360,857 kilometres.

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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Trio of Saturnian moons

Three of Saturn's moons

Three of Saturn's moons captured by NASA's Cassini spacecraft. From left: Dione, Rhea and Enceladus.

NASA’S CASSINI SPACECRAFT snapped this image of three of Saturn’s moons and part of the planet’s rings.

Saturn is not illuminated in this image, but it can be detected as the dark patch on the left that lies behind the foreground rings but in front of the background rings. It also partially obscures the moon on the left.

That moon is Dione (1,123 kilometres wide), around 3.1 million kilometres from Cassini when this image was taken.

In the foreground is Rhea (1,528 km wide). It is closest to the camera, at a distance of about 2.2 million kilometres.

The third moon, on the right, is Enceladus (504 km wide), seen at a distance of about 3 million kilometres.

Enceladus is the source of much interest at the moment, as Cassini’s instruments have detected huge plumes of salty spray shooting up from cracks near it’s south pole, suggesting a liquid ocean lies beneath the frozen surface.

More information:

Cassini-Huygens mission

Cassini imaging team homepage

Story by Jonathan Nally, SpaceInfo.com.au. Images courtesy NASA / JPL / Space Science Institute.

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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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What’s up? Night sky for June 2011

Skywatchers with telescopes

Stargazers are gearing up for the June 16, 2011, total eclipse of the Moon.

THREE OF THE NAKED-EYE BRIGHTNESS PLANETS will be visible in the eastern sky before sunrise this month. These are Venus, Jupiter and Mars. Mercury has left the scene, having dropped down to the horizon and become lost in the glare of the Sun.

In the evening sky, Saturn is holding it’s own, shining high and bright.

The major sky event this month for Australian skywatchers, is the total eclipse of the Moon on the morning of June 16.

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.

June 2

New Moon occurs today at 7:03am Sydney time (June 1, 21:03 Universal Time). New Moon is the opposite of Full Moon, and means

June 7-8

The almost half-full Moon will be near the star Regulus (the brightest star in the constellation Leo) over these two days. On the 7th it will be to the left of Regulus, and on the 8th it will be above it.

June 9

It is First Quarter Moon today at 12:11pm Sydney time (02:11 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 are throwing nice shadows, making it easier to get that 3D effect.

June 10

Look for the Moon to the left of the planet Saturn in tonight’s evening sky.

June 11

Tonight the Moon will appear quite close to the star Spica, the brightest star in the constellation Virgo.

June 12

Today the Moon will be at the closest point in its orbit, called perigee. The distance between the two bodies will be 367,189 kilometres.

June 13

The planet Mercury has been getting lower and lower in our morning sky, and has been lost in the glare of the Sun for a couple of weeks. Today, it reaches “superior conjunction“, which means that it is on the opposite side of the Sun from us.

June 14

Look for the almost-full Moon to the left of the planet Antares in tonight’s evening sky. Antares is a red supergiant star, 800 times the size of our Sun!

Total lunar eclipse

Don't miss the total lunar eclipse on the morning of June 16, 2011.

June 16 – total eclipse of the Moon

Full Moon occurs today at 6:14am Sydney time (June 15, 20:14 Universal Time). But the big news for today is the total eclipse of the Moon, which for Australian observers will occur in the hours before sunrise. The Moon will be in the western sky, and will gradually move into the Earth shadow and become dark, dropping lower and lower toward the horizon. During a total eclipse, the Moon takes on a reddish hue—sometimes pale, sometimes intense. This occurs because some of the Sun’s light filters through Earth’s atmosphere and is refracted onto the Moon.

For Australian observers, there’s more information on the total lunar eclipse (including timings) at the IceInSpace site.

For New Zealand observers, please see the Royal Astronomical Society of New Zealand’s site.

June 18

Low in the east before sunrise, you’ll see bright Venus below and to the left of a ruddy-coloured star. This is Aldebaran, a giant orange-coloured star about 65 light-years from Earth.

June 22

Today is the Southern Hemisphere’s midwinter solstice, which means that the Sun is at its furthest north in the sky (at 3:17am Sydney time, or June 21 at 17:17 Universal Time). This is the day when the hours of sunlight are at their minimum.

Stargazer looking at the sky

Enjoying the evening sky

June 23

It is Last Quarter Moon today at 9:48pm Sydney time (11:48 Universal Time).

June 24

Today the Moon will reach the farthest point in its orbit, apogee (the opposite of perigee), at a distance from Earth of 404,274 kilometres.

June 26

Have a look out to the east this morning, and you’ll see the crescent Moon quite near Jupiter.

June 29

Today the very thin crescent Moon will be just below the planet Mars in the pre-dawn eastern sky.

June 30

Finally, the very thin crescent Moon will appear above and to the left of the planet Venus. You can’t miss Venus – apart from the Sun and the Moon, it is the brightest object in the sky.

And finally, here’s the terrific Tanya Hill from the Melbourne Planetarium, with her Sky Notes for this month:

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.

Get SpaceInfo.com.au daily updates by RSS or email! Click the RSS Feed link at the top right-hand corner of this page, and then save the RSS Feed page to your bookmarks. Or, enter your email address (privacy assured) and we’ll send you daily updates. Or follow us on Twitter, @spaceinfo_oz

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What’s up? Night sky for May 2011

Stargazers looking at the sky

May will be a great month for planet watchers, with four bright planets visible to the east before dawn.

THIS WILL BE A FANTASTIC MONTH for planet watchers, with a series of attractive close groupings in the eastern morning sky. Mercury, Venus, Mars and Jupiter will be in the same part of the sky, and you’ll get the chance to watch their shifting positions as the month progresses.

Why do they appear to move around relative to each other? It’s because they’re on independent orbits about the Sun and travelling at different speeds. The Earth is moving around the Sun too, and our shifting perspective adds to the apparent sky motion. In fact, the word ‘planet’ comes from the Greek, and means ‘wandering star’.

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.

May 1

There’ll be a fantastic planetary get-together in this morning’s eastern sky. First, Jupiter and Mars will be just less than half a degree (roughly one Moon width) apart. Jupiter will be the brighter, whitish-coloured one on the right, with ruddy-coloured Mars on the left. Also present will be the crescent Moon … below and to the left of the planet Venus, and left of the planet Mercury, and above and to the left of the Jupiter-Mars pair. It’ll be a fantastic sight! Why not try taking a photo of it?

May 3

New Moon occurs today at 3:51pm Sydney time (06:51 Universal Time).

The Moon

The Moon is always a popular target for stargazers.

May 7

The planets Venus and Mercury will be side-by-side in this morning’s eastern sky, only 1.5 degrees apart (about three Moon widths).

May 8

Mercury, the innermost planet, will be at its greatest angular distance (27 degrees) from the Sun this morning.

May 11

It is First Quarter Moon today at 5:33am Sydney time (May 10, 20:33 Universal Time). The period around 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 this evening, the Moon will appear close to Regulus, 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, as many other stars are members of double, triple or quadruple systems too.

May 12

Another planetary grouping in this morning’s eastern sky, with Venus only half a degree (one Moon width) to the right of Jupiter, and Mercury about three Moon widths above and to the left.

May 14

This evening the almost-full Moon will be perched about 7 degrees above the planet Saturn.

May 15

Tonight the Moon, just a smidge short of being full, will be only 1.5 degrees (about three Moon widths) above and to the right of the star Spica, the brightest star in the constellation Virgo. Spica is a blue giant star, 7.4 times as big as our Sun, and the 15th-brightest star in our night sky. Also today, the Moon will be at the closest point in its orbit around the Earth, called perigee. The distance between the two bodies will be 362,133 kilometres.

Diagram showing planets in the morning sky

Four planets are visible in the morning sky. This diagram shows the view on May 16.

May 16

Yet another arrangement of planets in our morning sky to the east. Venus will be about three Moon widths below and to the left of Mercury, about eight Moon widths below and to the right of Jupiter, and about six Moon widths above ruddy-coloured Mars.

May 17

Full Moon occurs today at 8:09pm Sydney time (11:09 Universal Time).

May 18

Tonight, look for the Moon about four degrees (eight Moon widths) below and to the left of Antares. Antares is a red supergiant star, the brightest star in the constellation Leo and the 16th-brightest star in our night sky. And get this—Antares is 800 times the diameter of our Sun, so you can see why they call it a supergiant!

May 22-31

Venus, Mars and Mercury will do a dance with each other in the morning sky over the final week of the month, in close proximity to one another. Have a look each morning and see how the arrangement has changed.

May 25

It is Last Quarter Moon today at 3:52am Sydney time (May 24, 18:52 Universal Time).

May 27

Today the Moon will reach the farthest point in its orbit, apogee, at a distance from Earth of 405,003 kilometres.

May 30-31

The crescent Moon will join the Mars, Venus, Mercury triplet in the morning sky.

And here’s Melbourne Planetarium‘s fabulous astronomer, Tanya Hill, to show us what the month’s sky will look like in motion:

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 / TWAN / Babak A. Tafreshi / Andreas O. Jaunsen / IYA2009 / Galileoscope.

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