June is a spectacular time to look upwards. For one of the more special shows the skies can put on for us, all five visible planets can be sighted, and in a row, in the early morning sky during the month of June.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
Starting this weekend, and through most of June, if you look about 5:45am - 6am, you can see the line-up of the five visible planets - Saturn, Jupiter, Mars, Venus, and Mercury which has finally joined the party.
You need to look east and have a nice clear view. Saturn is visible from about 11pm, with Jupiter and Mars visible from about 2:30am, and Venus from about 4:30am. However, in order to see Mercury, you'll have to wait until about 5:45 - 6am for it to be high enough above the horizon. However, if you wait too late, the sun will start to rise, and it will get too bright, and you'll miss it.
High above, nearly straight up, is Saturn, followed by Jupiter lower in line, with Mars close-by, then Venus, and finally Mercury just above the horizon.
Seeing five planets in the night sky is the maximum we ever can, and not only are they all visible, they are in a beautiful line in the sky.
You can count Earth as the sixth as well, but we usually don't as it is always visible - unless something has gone horribly wrong. Also, of course, we have eight planets in our solar system, however Uranus and Neptune are too faint to see with the human eye. You really need a small pair of binoculars or a telescope to see them.
READ MORE SUNDAY SPACE:
Later in June, the moon will join the party moving by the planets for about a week. The best days will be the 24th and 25th of June, where the moon is in the gap between Mars and Venus, forming a beautiful line-up of Saturn, Jupiter, Mars, the Moon, Venus, and Mercury.
But why are the planets in a line? It has to do with perspective from Earth and the shape of our solar system! All the planets go around the sun in essentially the same plane or disc. Imagine the solar system as a frisbee, with the Sun at the centre, and all of the planets at various spots in the frisbee. Well if you turn the frisbee on its side, you'll get a line.
The line is called the ecliptic, or the plane of our solar system. As the Earth is tilted on its axis, which also gives us our seasons, this line is not straight across the sky, but at an angle.
Why are the planets in a line? It has to do with perspective from Earth and the shape of our solar system.
However, since the planets take different amounts of time to go around the Sun, as they are at different distances, they are not always visible in our sky, nor at the same time or relative position.
How often does this occur? For that, we need to look at how often they go around the Sun. Mercury orbits the sun every 88 days; Venus every 225 days; and Mars every 687 days or 1.88 years so they are regularly in our sky, and often at the same time.
Jupiter, and really Saturn, determine how often this happens. Jupiter orbits every 4,331 days or 11.87 years and Saturn every 10,747 days or 29.44 years.
It can happen when they are on one side of the solar system, or the other - in our morning sky or evening sky, so we don't have to wait the nearly 30 years for Saturn, but really half of its orbit around the Sun. This means is about every 18 years, next happening in 2040.
So be sure to look up in the morning in June, and see our solar system in action.
- Brad Tucker is an astrophysicist and cosmologist at Mount Stromlo Observatory, and the National Centre for the Public Awareness of Science at ANU.
Our journalists work hard to provide local, up-to-date news to the community. This is how you can continue to access our trusted content:
- Bookmark canberratimes.com.au
- Download our app
- Make sure you are signed up for our breaking and regular headlines newsletters
- Follow us on Twitter
- Follow us on Instagram