<P> The Houston Astros are an American professional baseball team based in Houston, Texas . The Astros compete in Major League Baseball (MLB) as a member club of the American League (AL) West division, having moved to the division in 2013 after spending their first 51 seasons in the National League (NL). The Astros have played their home games at Minute Maid Park since 2000 . </P> <P> The Astros were established as the Houston Colt . 45s and entered the National League as an expansion team in 1962 along with the New York Mets . The current name--reflecting Houston's role as the control center of the U.S. space program--was adopted three years later, when they moved into the Astrodome, the world's first domed sports stadium . </P> <P> The Astros played in the NL from 1962 to 2012 . They played in the West Division from 1969 to 1993, and the Central Division from 1994 to 2012 . While a member of the NL, the Astros played in one World Series, in 2005, against the Chicago White Sox, in which they were swept in four games . In 2017, they became the first franchise in MLB history to have won a pennant in both the NL and the AL, when they defeated the New York Yankees in the ALCS . They subsequently won the 2017 World Series against the Los Angeles Dodgers, winning four games to three, earning the team, and Texas, its first World Series title . </P> <P> From 1888 until 1961, Houston's professional baseball club was the minor league Houston Buffaloes . Although expansion from the National League eventually brought an MLB team to Texas in 1962, Houston officials had been making efforts to do so for years prior . There were four men chiefly responsible for bringing Major League Baseball to Houston: George Kirksey and Craig Cullinan, who had led a futile attempt to purchase the St. Louis Cardinals in 1952; R.E. "Bob" Smith, a prominent oilman and real estate magnate in Houston who was brought in for his financial resources; and Judge Roy Hofheinz, a former Mayor of Houston and Harris County Judge who was recruited for his salesmanship and political style . They formed the Houston Sports Association as their vehicle for attaining a big league franchise for the city of Houston . </P>

How many times have the astros appeared in the world series
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