Source | China News Network
According to Guangzhou Wuyang Astronomy Museum prediction: On September 27 this year, the night sky will stage the astronomical phenomenon of " Jupiter opposition to the sun ". This time, Jupiter opposition is extremely rare. Because Jupiter is close to the earth and the brightness of Jupiter, it is the highest in 71 years. If you miss the opportunity to observe this Jupiter opposition, you will have to wait for another 107 years.
▲ Schematic diagram of Jupiter's opposition day Li Xuyan drew
Experts explained that Jupiter's opposition day refers to Jupiter, the earth and the sun being arranged in a straight line in sequence. During the opposition of Jupiter, Jupiter is closest to the earth, with the largest and brightest diameter.
According to reports, This year's Jupiter opposition, there will be opportunities to watch it in China and even around the world. From September 24 to 30, around midnight (22:00 to 2:00 the next day), Jupiter radiated charming light over the Earth's equator, becoming the brightest celestial body in the night sky (the sun, moon, and Venus are all below the horizon). The public living in the equator of the Earth can see Jupiter above his head.
Since Jupiter orbits around the sun, its eccentricity is 0.0486, which is larger than the eccentricity of the earth's orbit 0.0167. Jupiter orbital cycle is 11.862 years, so in about 12 years, Jupiter will move to the location closest to the sun, that is, Jupiter's perihelion. If Jupiter opposition to the sun is near the perihelion point, Jupiter will be closest to Earth, and Jupiter's visual brightness will reach a great level. On January 21 next year, Jupiter passes perihelion. Therefore, this time, Jupiter's opposition to the sun is closest to the earth, only about 591.3 million kilometers, with an apparent diameter of 49.88 arc seconds and a negative magnitude of 2.9 stars, which is the brightest since October 3, 1951 (Jupiter's opposition to the sun). The next time Jupiter is closer and brighter to the earth, it will take 107 years, that is, it will wait until October 7, 2129 (Jupiter opposition sun).
Experts say that the best time to observe Jupiter is in the middle of the sky. At this time, Jupiter is located directly south and becomes a veritable "compass", and the horizon is the largest, the atmosphere through which the starlight passes is the thinnest, and it is easiest to observe and photograph. In Guangzhou, the time for Jupiter to go up to the middle of the sky: September 27 is 0:16 (the height of the horizon is 67 degrees); October 7 is 23:32; October 17 is 22:48; October 27 is 22:05. Recently, the time for Jupiter in the middle of the sky around the world has been around 4.4 minutes earlier than the previous day on average.
Jupiter opposition to the day, and it appears once every 399 days on average. The last time happened on August 20, 2021, and the next time will appear on November 3, 2023.
