Star Spy: New year begins

22:26, Dec 05 2012
Galilean moons rising
Galilean moons rising
Jupiter and Galilean Moons
Jupiter and Galilean Moons
Summer stars
Summer stars above Tekapo.

Matariki is a nearby cluster containing about 1000 stars, nearby in this case being just a few hundred light years away.

The group has many names, given by cultures around the world and throughout history, but is currently widely known as Pleaides, or the Seven Sisters. In Japan it is called Subaru. A large Japanese telescope on Mauna Kea is named for it, as is a well-known car manufacturer.

Once you sight Jupiter, shining brightly to the north, you will find Matariki about one hand width to the left (fingers and thumb together, not spread out), a light fuzzy area quite visible in a dark moonless sky, which we will have through the 15th or 16th of the month.

Remember that the sky is not really dark in summer until after 11pm or so. Also note that the position of Jupiter against the stars changes slowly through the summer.

In perfect viewing conditions, and using just your eyes you may see up to 14 of the brightest blue-white stars. 

The most I have clearly distinguished is six, twinkling on and off from disturbances in the atmosphere.


Maori custom varies from iwi (tribe) to iwi, but for most, the first time Matariki is spotted rising before the Sun is related to the start of the new calendar year.

Matariki, rising earlier each night, then leads our summer constellations slowly from east to west, into our night sky.

Unlike the constellations, Matariki is not just a pattern of stars in the sky.

It is a true group of stars that were born together from a collapsing cloud of dust and gas. 

The blue reflection nebula you see surrounding the stars in Fraser’s image above, is a cloud of dust and gas in our galaxy through which the cluster is currently passing. 

The blue colour is the result of the blue component of the light from the main bright stars, reflecting and scattering off the cloud’s particles.

The stars in the cluster will likely continue to travel through the galaxy together for a few hundred million more years, and will gradually disburse, each star going its separate way.  


Named for a Roman god, Jupiter is the largest planet in the solar system and the fourth brightest object in our sky after the Sun, the Moon, and Venus. 

Earth passed it this week, on our faster inner track around the Sun, our closest approach to Jupiter until the next time around. 

While Jupiter takes almost 12 Earth years to complete one orbit, one Jovian year, it has the shortest day of all the planets, taking just 10 hours to complete one rotation on its axis. 

It isn’t a secret, but many are not aware that, in addition to its 67 known moons, Jupiter also sports a system of rings. 

There are four main rings, very dim and consisting mostly of dust particles.

They do not put on a spectacular show of light and shadow like the brighter, more numerous and extensive rings of Saturn.

Voyager 1 was the first to spot them as it visited Jupiter in 1979 on its epic voyage beyond the solar system. 

Jupiter’s rings do not appear in Fraser’s image above because they are only visible from Earth using the largest telescopes. 

The rings orbit Jupiter between the planet and Io, the innermost Galilean moon. 

They are accompanied by four small moons, some of which contribute to the rings the dust and debris from their collisions with smaller objects in the Jovian System.