Tickets for the Museum of Life and Science's annual Santa Train are selling fast, according to museum vice president Julie Ketner Rigby.

As of 3 p.m. Monday, about 1,000 tickets remained unsold — 20 percent of the total that went on sale last week.

"It always sells out," Rigby said; last year's tickets were gone in four days.

The Santa Train runs Wednesday–Sunday, Dec. 3-7, 10-14 and 17-21, from 5:40 to 8:20 p.m. See www.lifeandscience.org.