On Feb. 18, 1930, 24-year-old Clyde Tombaugh discovered a faint, remote object on photographic plates he had taken Jan. 23 and Jan. 29 from Lowell Observatory in Flagstaff, Ariz.

Astronomers credited him with discovering the ninth planet orbiting the sun, and it was named Pluto.

It was so distant — farther than Neptune — and so small and faint that for several decades little was learned about Pluto beyond its orbital characteristics.

During the explorations of the 1970s and 1980s, knowledge about our planetary neighbors was greatly expanded when spacecraft landed on or flew by every other planet, except Pluto. And we’ve still not visited Pluto.

But that’s about to change.

On Jan. 19, 2006, NASA’s New Horizons spacecraft began its 9 1/2 year journey to the planet Pluto and beyond. But, ironically, before the craft even left the inner solar system, planet Pluto ceased to exist.

In July 2006, the International Astronomical Union, in a highly publicized and controversial decision, redefined “planet,” and Pluto was reclassified as a dwarf planet. It is now seen as one of the largest objects in the Kuiper Belt, a swarming cluster of small icy objects orbiting the Sun beyond Neptune. The Kuiper Belt issimilar to the asteroid belt, a swarming cluster of small rocky objects orbiting between Mars and Jupiter.

In July 2015, New Horizons will fly past Pluto and its three moons, making them the most remote objects to be studied up close. It won’t land, but after zooming within 6,000 miles of Pluto, it should return images to dazzle our imagination and enough data to keep scientists busy for years.

If funding is available, New Horizons will continue its exploratory journey with flyby visits to one or more other more distant Kuiper Belt objects between 2016 and 2020.

To read more about the New Horizons mission, visit www.pluto.jhuapl.edu.

* Next two weeks: Average sunrise: 7:12 a.m.; average sunset: 6:14 p.m.

Tomorrow morning the crescent moon is to the upper right of Scorpius’ brightest star, Antares, low in the southeast. Thursday morning, the crescent moon is to the upper right of Mercury very low in the east southeast at dawn, and then to the planet’s lower left the next morning.

The moon is new Feb. 13. In the early evening of Feb. 14, Jupiter is four moonwidths above brighter Venus with an ever-so-thin crescent moon to their left near the west southwestern horizon.

They will become visible soon after sunset and set soon thereafter; binoculars will help. Then in the early evening of Feb. 16, Jupiter is one moonwidth to the right of Venus very low in the west southwest just after sunset.

* Naked-eye planets: As twilight ends, Jupiter is setting in the west as Venus begins its stint as the “evening star.”

Mars is still prominent in the east. At dawn, Mercury is very low in the southeast, Saturn is higher in the southwest, and Mars is setting in the west northwest.

* Star party: The Central Texas Astronomical Society’s free monthly star party is tonight at the Lake Waco Wetlands beginning at 7 p.m., weather permitting.

For directions, see my Web site.

* Astro milestones: Feb. 15 is the 446th birthday of Galileo Galilei (1564-1642). Feb. 19 is the 537th birthday of Nicolaus Copernicus (1473-1543).

Stargazer appears every other Saturday. Paul Derrick is an amateur astronomer who lives in Waco. Contact him at 918 N. 30th St., Waco 76707, (254) 753-6920 or paulderrickwaco@aol.com. See the Stargazer Web site at stargazerpaul.com.