When the Apollo 11 spacecraft lifted from the moon in July 1969, it left behind a plaque that read in part “We came in peace for all mankind.”

This sentiment has become part of space folklore but what is all but unknown is that another memorial was left as well in the form of a small white pouch containing a silicon disk about the size of a half-dollar. On the disk, in letters about a quarter the diameter of a human hair, are etched 73 messages of peace from leaders around the Earth in languages ranging from Chinese and Arabic to Hebrew and French. The message from Pope Paul VI even included intricate artwork.

The disk was meant to be the primary message from the people of Earth to whoever might discover it in the future; in actual fact, it was almost forgotten.

As Buzz Aldrin climbed the ladder to enter the spacecraft he remembered the pouch in an arm pocket of his suit and tossed it down to Neil Armstrong. He, in turn, nudged it beneath the surface a few inches from his famous footprint next to the leg of the lander. There it will remain until some future space traveler happens across it.

A recent book on the disk is Tahir Rahman’s “We Came in Peace for All Mankind: The Untold Story of the Apollo 11 Silicon Disk.”

Focus on the planets

Mercury peeks briefly over the southwest horizon at dusk starting around Jan. 15 and remains in view for about an hour and a half.

Venus may be found high on the southeastern horizon at dawn as the month opens but descends slowly toward the horizon each day.

Mars is well up in the east as darkness falls and is situated high in the southwest after midnight early in January. Mars is visible nearly all night but is rapidly receding from Earth with a corresponding decrease in size and brightness.

Jupiter starts the month too close to the southeast horizon to be seen easily.

Saturn rises on the eastern horizon about 9 p.m. among the stars of Leo. The planet’s fabled ring system continues to narrow so, while that will be a disappointment to viewers, it does make seeing the movement of its moons across the planet’s disk easier.

Neptune is low in the southwest among the stars of Capricornus and lost in the glow of twilight in January.

Uranus is low in the south as night falls but may be spotted among the stars of Aquarius with a strong telescope and finder’s chart.

January events

1 Sunrise, 7:13 a.m.; sunset, 4:05 p.m.

8 New moon, 6:36 a.m.

14 Today was Jan. 1 on the old Julian calendar that was superseded by the Gregorian calendar in 1582.

15 Moon in first quarter, 2:45 p.m.

19 The moon is at perigee or closest approach to Earth today. Mars, with the crescent moon in attendance to its upper left, is surrounded by the brightest stars of several constellations as you look to the southeast around 8 p.m. Directly to the left of Mars are Castor and Pollux of Gemini, directly above is Capella of Auriga, to Mars’ immediate lower right is Aldebaran, the “red eye” of Taurus, and farther to the lower right are Betelgeuse and Rigel of Orion respectively.

20 The sun is entering Capricornus on the ecliptic but astrologically, because of precession, is entering the sign of Aquarius.

22 Full moon, 8:34 a.m. The full moon of January is known by several names including the Wolf Moon, Old Moon, Moon After Yule, and the Ice Moon or Winter Moon.

30 Moon in last quarter, 12:02 a.m.

31 Look for Venus and Jupiter, which have been creeping toward one another all month, to have a spectacular meeting on the southeastern horizon at dawn.

The moon is at apogee for the second time this month. Sunrise, 6:56 a.m.; sunset, 4:42 p.m.

Send astronomical queries to Clair Wood at cgmewood@aol.com or care of the Bangor Daily News, Style Desk, P.O. Box 1329, Bangor 04402.