Planetary Parade January – February
During this holiday season watch a Parade of Planets crossing the sky. Venus, Saturn, Jupiter and Mars are arrayed across the northern sky, and readily seen by eye, this January and February. You can find all these planets on our January Star Map. Here's what to look for:
An hour after sunset look due west. The bright white "star" over there is Venus — currently we would call it the "evening star".
Saturn begins the year above-right of Venus and moves down and left as the days pass. It's faint compared to Venus this year (the rings are almost edge-on this year and therefore reflecting very little light our way). So the best way to identify Saturn is at it's closest to Venus — on January 18–19 look about four Moon-widths above and left of Venus. Saturn is slightly yellowish, but brighter than any star nearby.
Turn to face North and there is Jupiter, very bright and yellow in the constellation Taurus. Don't mistake Jupiter for the fainter, orange star Aldebaran above.
Further to the right, in the North-East, is Mars, bright also as it's closest to Earth in January. Mars appears an orange-red colour. Of course, as the night passes you will see the planets parade across the sky, in step and heading for the western horizon.
Earth Perihelion 5 January
The Earth and planets orbit the Sun in nearly circular orbits, but not quite. Their orbits are elliptical and some more than others. The Earth’s orbit is just 1.7% off a perfect circle while Mercury has the greatest eccentricity of 2.1%. The point at which a planet is at its closest part of its orbit to the Sun is known as perihelion. The most distant is aphelion. For the Earth, perihelion in 2025 is on Sunday 5 January at 12:28 am AEDT at a distance of 147,103,686 km.
Opposition of Mars 16 January
The red planet Mars is directly opposite the Sun reaching its highest point in the sky around midnight local time. This usually means it is at its closest and brightest for the last 26 months (the time it takes Mars and the Earth to come close). This year’s opposition will not be as close as others though Mars’ disc will be easily seen through a small telescope. The next favourable opposition of Mars is in June 2033 while the best in the next thousand years will be in September 2729 when it will be 55,651,099 km away.
Venus near Saturn 18–19 January
The brightest planet, Venus, is close to the ringed planet Saturn in the constellation of Aquarius in the western twilight sky. They will be 2.5 degrees apart or five times the width of the Full Moon. This is known as a conjunction and there are 14 in 2025, with the closest between Mercury and Neptune on 17 April separated by 41minutes of arc (1.3 Moon widths) apart at 4:32 am AEST.
