Chandra Observations: X-Ray Observatory Targets and Calibration Data

Chandra X-Ray Observatory observations include Performance Verification, calibration, and all subsequent cycles of Guaranteed Time and General Observer targets. The HEASARC updates this database twice-weekly by querying the Chandra X-Ray Center. NASA HEASARC provides this service, with data products available from the Chandra Data Archive for archived observations.

Use Cases

• Analyzing observation scheduling and target selection based on mission cycle and observer type (GTO, GO, DDT)
• Studying calibration data trends based on entries flagged with Type = CAL
• Tracking data availability and archival status for specific astronomical targets
• Researching the temporal distribution of observations across the mission's operational phases

Strengths

• Includes all observations from the mission's Performance Verification and Calibration phase onward
• Updated on a twice-weekly basis, suggesting relatively current metadata
• Data from archived observations is retrievable from a public mirror of the Chandra Data Archive

Limitations

• Column-level documentation is absent; field semantics must be inferred after download
• Row count is unknown, which may limit suitability assessment
• Description metadata is limited; actual data quality requires manual inspection after download

Provenance

Source

Chandra X-Ray Center (CXC), NASA HEASARC

Collection Method

Updated twice-weekly by querying the database table at the CXC website

Time Range

From the mission's Performance Verification and Calibration phase onward

Freshness

Last updated 2026-03-13 20:10:03.823867; updated twice-weekly.

Geography

Celestial observations, spatial coverage not specified