No future Astros, only former Astros with birthdays today ~
3B Bob Aspromonte (74)
Aspro the Astro was one of the original Colt .45s and Astros players, having been obtained in the expansion draft in October of 1961. In seven seasons with the Astros, Aspromonte hit .258/.313/.345 with his best season being 1967 when he hit .294/.354/.401. He was traded in December 1968 to Atlanta for utility player Marty Martinez. He led the National League in fielding percentage in 1964 and 1971.
LHP Jerry Reuss (63)
A second round pick by the Cardinals in 1967, Reuss came to Houston in a trade in April 1972, was traded away in October of 1973 and came back to Houston as a free agent 17 years later in 1990 toward the end of a 22-year major league career (but didn't pitch for Houston again at the major league level). In 1972 and 1973, Reuss was 25-26 in 74 games for the Astros with a 3.91 ERA and a 1.375 WHIP. He won 18 games in three different seasons and was an All-Star in two of those, in 1975 for the Pirates and in 1980 for the Dodgers. He came in second in Cy Young voting in 1980 to Steve Carlton.
2B Craig Smajstrla (50)
Originally drafted in the fourth round in 1981 by the White Sox, Smajstrla (can I buy a vowel?) came to Houston as a free agent in November of 1987. His eight games for the Astros in 1988 constituted his entire major league career. Used mostly as a pinch runner, he scored two runs but never got a hit in his three at bats.
LHP Bruce Chen (35)
Atlanta signed Chen as a free agent out of Panama in 1993. He came to Houston as a free agent in March of 2003 and only pitched in 11 games before being placed on waivers. In 12 innings, he had an ERA of 6.00 and a WHIP of 1.833. He is currently pitching for the Kansas City Royals.