In early March, a remarkable celestial event will unfold, allowing observers on Earth to view seven of our solar system’s planets aligning in the night sky. According to Dr Rebecca Allen, co-director of the Swinburne Space Technology and Industry Institute, four of these planets—Mars, Venus, Jupiter, and Saturn—have been visible to the naked eye in Australia since January. This planetary alignment presents a rare opportunity, as generally, watching multiple planets simultaneously is uncommon due to their varying speeds and positions in relation to the sun.
The alignment consists of six planets, with Neptune and Uranus potentially observable through a telescope. This planetary parade can be seen across much of the globe and is expected to be particularly prominent throughout the summer months. Dr Allen explained that while such alignments occur annually, having six or seven planets visibly lined up is a much rarer phenomenon.
To maximise visibility, it’s advised to escape city lights and find spacious, elevated areas. Ideally, observers should favour clear skies, with the best viewing time shortly after sunset. Starting in the west, one can first spot the bright pair of Venus and Saturn, followed by Jupiter, which hovers above the constellation Taurus, with Mars positioned further east in Gemini. Notably, in the coming weeks, Mercury will join this planetary showcase, completing the celestial procession.
Planetary alignments do not signify a precise queue of planets; instead, they simply appear to line up from our perspective on Earth. This illusion occurs because, although planets occupy different distances and orbits around the sun, they can appear close together against the backdrop of our night sky. All planets follow the ecliptic—the same plane along which the sun rises and sets—which allows for these spectacular views of their alignment.
Astrophotography apps like StarWalk or Stellarium can enhance the stargazing experience, helping enthusiasts identify and learn more about the visible planets. As summer progresses, this unique planetary alignment promises to offer breathtaking sights and an engaging opportunity for both avid astronomers and casual sky watchers alike.