Those with knowledge of astrology are familiar with the phrase “Mercury is in retrograde.” Perhaps a lesser known Mercury phenomenon is its greatest elongation east. This will occur in the evening sky tonight (Monday, July 22), making Mercury easier to see with the naked eye after sunset.
Here’s what you need to know before you go planet gazing. We can’t comment on how this will impact your love life, though.
Quick facts about Mercury
Mercury is tricky to see most of the time because of its speed and proximity to the sun. It is the closest planet to the star. Mercury is tiny but mighty. It is the smallest planet in our solar system but has an iron core that makes up three-fourths of its mass.
The planet is named after the Roman god of the same name who was in charge of business, messengers, travelers, and trickery. He was also fast so the name is fitting. The planet orbits the sun every 88 Earth days.
Greatest elongation
The best time to see Mercury without fancy telescopes is when the planet is in its greatest elongation east or west. It is at these times that the planet is the farthest from the sun. This happens twice around every 116 days, or around every four months.
When Mercury is in the greatest elongation east, the sun and the planet are the farthest apart in the night sky. When the planet is in the greatest elongation west, the morning sky puts on the show.
If you can’t sky gaze tonight, don’t worry. This celestial event lasts about a week. You can try again tomorrow.
Most days, Mercury appears to be directly behind the sun or in front of it. The official terms for that are superior conjunction or inferior conjunction, respectively.
A word to the wise
Always use caution when looking into the sky because of the sun. Do not point telescopes or binoculars directly into the bright ball of gas. Your vision is more important than a planet sighting.