Every few hundred years most of the planets line up on the same side of the Sun
The phenomenon you're referring to is called planetary alignment. While it is true that the planets in our solar system occasionally appear to align on one side of the Sun, this particular alignment pattern does not occur every few hundred years. In fact, a complete alignment of all the planets in our solar system is extremely rare and has never been recorded in human history.
However, there are certain planetary alignments that occur within shorter timeframes. For example, the alignment of inner planets (Mercury, Venus, Earth, and Mars) can occur approximately every 100 years. It's important to note that these alignments are not perfectly straight lines, but rather occur within a narrow region of the sky.
To track and determine the occurrence of planetary alignments, you can use various astronomical tools and resources. Here's how you can do it:
1. Astronomical Almanacs: These books or online references provide detailed information about celestial events, including planetary positions and alignments. They usually include predictions for several years in advance.
2. Planetarium Software: Planetarium software, such as Stellarium or SkySafari, allows you to simulate the night sky and view the alignment of planets at any given date and time. You can adjust the time settings to see if there will be any upcoming alignments.
3. Online Astronomy Websites: Numerous websites dedicated to astronomy provide real-time data, forecasts, and interactive sky maps that can help identify planetary alignments. Some popular examples include NASA's Solar System Exploration website and the Jet Propulsion Laboratory's Solar System Dynamics website.
By using these tools, you can keep track of upcoming planetary alignments and observe these celestial events when they occur. Remember, while planetary alignments may be fascinating to witness, a complete alignment of all planets on one side of the Sun is an infrequent and extraordinarily rare occurrence.