September 2010 can make for some memorable viewing experiences for stargazers. One of the biggest highlights is experts say mid to late month is to be a great time to get a sharper observation of Jupiter.
Jupiter and Earth encounter each other every 13 months, however due to their oval shaped orbits, do not meet at the same closeness every time. Jupiter is expected to be prominent on clear nights, however the view is anticipated to be at its peak come Monday, September 20th when at this time the planet will be 368 million miles away. Reportedly Jupiter can be best seen shortly after twilight, as the planet will be sitting low in the east. The large planet will then move higher as the night hours pass (Space.com via MSNBC).
Jupiter is the largest planet in our solar system. With a diameter of 88,846 miles and 11 times larger than Earth, Jupiter is typically a bright planet when gazed upon from Earth (NASA). Even during normal times the only celestial body in the skies brighter than Jupiter is the Moon, so this timeframe when Jupiter comes close is expected to provide additional brightness.
Space.com further explains both the planetary orbits and reasons why Jupiter and Earth will come so close together this year as opposed to other years. They state "Earth orbits the sun in about 365 days. But Jupiter, farther out there, takes 4,332 Earth-days to make the same trip. Therefore, Earth laps Jupiter periodically, on the inside track. As that pass occurs, the two worlds come much closer than when they are on opposite sides of the sun. Because the planets' orbits are not perfect circles, some passes are tighter than others."
So for those inclined to spend some time exploring the darkened skies, it seems now is the prime time to get this type of rarer celestial viewing experience. In August 2009, Jupiter was an additional 7 million miles away making the planet appear 8 percent dimmer than it will appear this year. The last time Jupiter was close enough to get this type of spectacular view was back in 1963.
In addition to this primary event, other planets are coming closer into Earth's view during this timeframe. Uranus is not visible to the naked eye, but with visual aid tools such as binoculars or telescopes, this planet can be seen, albeit it will appear 3,000 times dimmer than Jupiter; this will occur through September 24th. Mercury is also making one of its biannual visits where the planet is highly visible during this week once in the morning and once in the evening (Space.com).
Although stargazers who either have cloudy conditions or cannot partake in viewing Jupiter on the 20th, should not fret as the gas and liquid comprised planet will still be viewable after this date for a limited time.
Jupiter is not expected to be this close in proximity to Earth again until the year 2022.