Expert says the planet parade will be best viewed around 21 January and recommends downloading a sky map app to help see when the planets align

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Stargazers are being treated to a rare planetary alignment this month, also known as a “planet parade”, with most of the planets visible in the night sky at the same time.

Astrophysicist Dr Rebecca Allen, co-director of Swinburne University’s space technology and industry institute, said it would be a rare opportunity to see so many planets align, especially outer ones such as Neptune.