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The five-planet parade continues with its last best week, with Venus, Jupiter and Saturn easy to see and Neptune at its annual opposition on Tuesday. It's also the autumnal or fall equinox on Monday, Sept. 22 -- along with a dramatic solar eclipse in the Southern Hemisphere.
Neptune's opposition is its brightest appearance of 2025, though it remains just a faint star-like point. According to When The Curves Line Up, it sits above Saturn in the same field of view, though it is much dimmer. Its brightness and proximity to Saturn makes this week the ideal time to tick the solar system's most distant (and most difficult to see) planet off your observing list.
On Monday, Sept. 22, skywatchers in New Zealand, Antarctica, and parts of the South Pacific will witness a very deep partial solar eclipse at sunrise when as much as 86% of the sun will be blocked by the moon during sunrise. TimeAndDate.com is streaming the entire event live at 18:00 UTC (1:00 p.m. EDT) on Sunday, Sept. 21 (the dates reflect the fact that the eclipse takes place close to the international date line). It's the second and final partial solar eclipse of 2025.