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Observing Mercury (planet) through a telescope
Mercury is the first planet from the Sun and the smallest in the Solar System. It is a rocky planet with a trace atmosphere and a surface gravity slightly lower than that of Mars.
What Mercury (planet) is
Mercury is the first planet from the Sun and the smallest in the Solar System. It is a rocky planet with a trace atmosphere and a surface gravity slightly lower than that of Mars. The surface of Mercury is similar to Earth's Moon, being cratered, with an expansive rupes system generated from thrust faults, and bright ray systems, formed by ejecta. Its largest crater, Caloris Planitia, has a diameter of 1,550 km (960 mi), which is about one-third the diameter of the planet. Being the most inferior orbiting planet, it always appears close to the Sun in Earth's sky, as either a "morning star" or an "evening star". It is the planet with the highest delta-v required for travel from Earth, as well as to and from the other planets in the Solar System.
Observing Mercury (planet) through a telescope
Mercury never strays far from the Sun, so it is only visible low in twilight. A telescope shows it as a tiny disc going through phases like the Moon, but atmospheric turbulence near the horizon limits detail.
Planets and the Moon reward higher magnification than deep-sky objects, but only up to what the air will allow: on a turbulent night the image boils and less power shows more. Magnification is your telescope's focal length divided by your eyepiece's focal length, so a shorter eyepiece gives more power. Use the Fit My Telescope tool to see the magnification and exit pupil each of your eyepieces gives before you observe.
Mercury (planet) in NASA imagery
NASA has imaged Mercury (planet) in detail. One example in the NASA Image and Video Library is titled Long Scarps on Mercury Tell of the Planet Unique History, from JPL. NASA imagery is in the public domain.
What magnification suits Mercury (planet)?
Open the Fit My Telescope toolSee the magnification and exit pupil each eyepiece givesFind telescope eyepiece on eBayaffiliateRelated
Sources: Mercury (planet) (Wikipedia, CC BY-SA) · Wikidata (CC0) · NASA Image and Video Library: PIA13477 (public domain)