The planet Neptune makes a great appearance — and disappearance — next month.

On June 23, the waning gibbous moon will occult Neptune about 3:48 a.m. The giant gas planet will reappear from behind the moon an hour and a half later, during twilight, about 5:11 a.m. Neptune's brightness, at magnitude 7.9, is a bit beyond the limit of human vision, so you will need at least binoculars to view this rare event.

Mercury, fairly bright at magnitude 1.7, can be seen over the last week of June during morning twilight in the constellation Taurus, on the east-northeast horizon. Again, binoculars will be necessary to spot the planet against the brightening sky.

Venus remains near the sun in June, but reappears in July as an evening planet, and will remain so for the rest of 2008.

Mars continues its journey, moving from Cancer back into Leo. At midnight June 7, Mars passes within 2 degrees of the waxing crescent moon on the west-northwest horizon. Within half an hour, both the moon and Mars will drop below the horizon.

At 2:50 a.m. June 20, Jupiter stands right in the south, 30 degrees above the horizon, within 4 degrees of the waning gibbous moon.

Saturn remains near Regulus in Leo. You still have a few months to catch the ring system before it closes up this winter, and then you'll have to wait until next spring to see the rings as open as they appear right now.

June 21 marks the summer solstice, the longest day and the shortest night of the year. The peak of the Lyrid meteor shower is June 14-16. You may see up to 10 meteors per hour during these nights.

Q&A

Q: I know that the Earth rotates on its axis, and that we also revolve around the sun. Just how fast are we traveling? — S.R., Canton

A: At the equator, the Earth is spinning about 1,040 mph. The earth orbits the sun at 66,600 mph.

Beyond that, the whole solar system travels around the galactic center (once every 225 million years) about 450,000 mph, and the entire Milky Way galaxy is moving (relative to nearby galaxies) at 1,342,262 mph.

Dizzy yet?

Program

The Hoover-Price Planetarium is showing Comet Tales through July 11. Throughout history, comets have been portents of good and bad events, but are mostly just beautiful objects in the night — and sometimes day sky. We'll be looking at some of these old and very new visitors from the far reaches of the solar system.

Presentations are at 1 p.m. Saturdays and 2 p.m. Sundays. From June 9 through Labor Day, weekday planetarium shows are at 1 p.m. The planetarium is included with admission to the William McKinley Presidential Library & Museum. Call 330-455-7043.