The Hubble Space Telescope has completed what NASA calls its “annual grand tour of the Solar System,” capturing stunning views of the four gas giants – Jupiter on 4 September; Saturn on 12 September; Uranus on 25 October; and Neptune on 7 September. Even though passing spacecraft and orbiters have sent back close-up views of all four worlds and multiple moons during visits over the past half century, the cold atmospheres of the gas giants are always changing. Using Hubble to keep tabs on Earth’s outer Solar System neighbours provides valuable insights into the dynamic processes at work under the cloudtops that shape weather patterns and seasons.
Astronomers using the Hubble Space Telescope trace a supernova’s history by measuring how fast left over debris is moving, concluding light from the blast reached Earth during the decline of the Roman Empire 1,700 years ago.
Even casual skywatchers cannot fail to notice brightest planet Venus currently hanging like a lantern above the southwest horizon at dusk. But as Venus moves eastwards through Aquarius on successive nights, it draws closer to outermost (and faintest) planet Neptune until the pair reach a particularly close conjunction on the UK evening of Monday, 27 January.