Group 1 - The core event of Neptune's opposition occurs on September 23, 2023, providing the best opportunity for observation as it will be at its closest distance to Earth, with maximum brightness and apparent diameter [2][4] - Neptune's brightness during this opposition is approximately 7.7 magnitude, making it invisible to the naked eye and requiring a telescope with a minimum aperture of 10 centimeters for observation [4][6] - The opposition of Neptune happens every 367 days, with the previous one occurring on September 21, 2024, indicating a consistent cycle for astronomical events [2] Group 2 - The proximity of Saturn and Neptune during this period allows observers to use Saturn, which has a brightness of about 0.6 magnitude, as a reference point to locate Neptune in the night sky [6] - Observers are advised to utilize telescopes with larger apertures, ideally 20 centimeters or more, to potentially view Neptune's blue disk [6]
星空有约丨海王星又要“露脸”啦！如何观赏
Xin Hua She·2025-09-21 04:14