Question: Which observatory/satellite was launched into space first, Hakucho or Chandra X-ray Observatory?
Sentence (from "Chandra X-ray Observatory"): The Chandra X-ray Observatory (CXO), previously known as the Advanced X-ray Astrophysics Facility (AXAF), is a Flagship-class space observatory launched on STS-93 by NASA on July 23, 1999.
Relevant evidence: Yes