Mercury will briefly reveal itself before dawn tomorrow (June 16) when the planet reaches its longest separation from the sun as seen from Earth, also known as its largest western extension.
The elusive planet Mercury will reach a maximum angle of 23 ° west of the sun; viewers who are close to the equator and further south will experience the best viewing options.
“Between 4:30 a.m. and 5 p.m. in your local time zone, look for the planet with a magnitude of 0.45 that shines very low in the east-northeast sky,” writes geophysicist Chris Vaughan, amateur astronomer with SkySafari Software that monitors Space.com’s Night Sky calendar. “It will be placed with a fist diameter at the bottom left for much brighter Venus.”
The exact time of the event varies depending on your specific location, so you should check out a skywatching app like SkySafari or software like Starry Night to look for times. Our selections for the best stargazing apps can help you with your planning.
“Do not worry if the sky is cloudy on Thursday,” Vaughan said. “Mercury will be almost as far from the sun in the mornings around”.
Related: The brightest planets in the June night sky: How to see them (and when)
Mercury is usually a difficult planet to spot since its orbit is closer to the sun than the earth’s, and is often obscured by the sun’s glare. The best time to watch Mercury is when the planet reaches its greatest elongation – its greatest angular distance from the sun. According to In-The-Sky.org (opens in new tab) these appearances occur approximately every three to four months.
Mercury glides around the sun every 88 Earth days, traveling through space at almost 180,000 km / h, faster than any other planet. In 2019, a rare transit of Mercury occurred where the planet crossed the surface of the sun. This will not happen again until 2032.
If you are looking for a telescope or binoculars to see planetary extensions as tomorrow’s event, our guides to the best binocular deals and the best telescope deals can now help. Our best astrophotographic cameras and best astrophotographic lenses to prepare for capturing the next stargazing vision in an image.
Editor’s note: If you snap a photo of Mercury and want to share it with Space.com readers, send your photos, comments and name and location to email@example.com.