The Rossi X-ray Timing Explorer (RXTE) Index table was created for the purpose of providing a concise and easily accessible tracking of RXTE observations, both those already completed and those still scheduled to be done. Each entry in this table corresponds to a specific proposal/target combination or `complete observation', in contrast to the RXTE Master table in which each entry corresponds to a specific proposal/target/ObsID combination or `observing segment'. A complete observation can consist of many (in some cases dozens) observing segments. This is a service provided by NASA HEASARC .

The XTEAO database table contains the official observing program for the Rossi X-Ray Timing Explorer (RXTE) satellite. This list contains the targets recommended by the review panels for the various Cycles of Guest Observer (GO) proposals up to and including Cycle 15. Notice that not all entries in this list will actually be observed, since it includes observations of Targets of Opportunity (ToOs) which may never be triggered. Also note that multiple pointings at a particular target are permitted. This database table was updated by the HEASARC periodically, based on information provided by the RXTE Guest Observer Facility (GOF). This is a service provided by NASA HEASARC .

The XRAY database table contains selected parameters from almost all HEASARC X-ray catalogs that have source positions located to better than a few arcminutes. The XRAY database table was created by copying all of the entries and common parameters from the tables listed in the Component Tables section. The XRAY database table has many entries but relatively few parameters; it provides users with general information about X-ray sources, obtained from a variety of catalogs. XRAY is especially suitable for cone searches and cross-correlations with other databases. Each entry in XRAY has a parameter called 'database_table' which indicates from which original database the entry was copied; users can browse that original table should they wish to examine all of the parameter fields for a particular entry. For some entries in XRAY, some of the parameter fields may be blank (or have zero values); this indicates that the original database table did not contain that particular parameter or that it had this same value there. The HEASARC in certain instances has included X-ray sources for which the quoted value for the specified band is an upper limit rather than a detection. The HEASARC recommends that the user should always check the original tables to get the complete information about the properties of the sources listed in the XRAY master source list. This master catalog is updated periodically whenever one of the component database tables is modified or a new component database table is added. This is a service provided by NASA HEASARC .

The X-Ray Imaging and Spectroscopy Mission (XRISM) is an international mission led by Institute of Space and Astronautical Science (ISAS) of Japan Aerospace Exploration Agency (JAXA). XRISM was launched on 2023 September 6 (UT) into a near-circular orbit with an apogee of ~575 km, an inclination of ~31 degrees, and an orbital period of about 96 minutes. During the performance verification (PV) phase, targets selected by the XRISM science team are being observed. Subsequently, it will become a general observatory with annual call for proposals open to all astronomers. XRISM has two co-aligned instruments that are used concurrently: Resolve, a soft X-ray spectrometer, and Xtend, a wide field-of-view imager. Resolve uses an X-ray microcalorimeter with ~5 eV spectral resolution withs a 3x3 arcmin field of view. It is currently operating with the Gate Valve closed, which limits its effective bandpass to 1.7-12 keV. Xtend is an X-ray CCD instrument with a 38 x 38 arcmin² field of view. This table contains a list of observations that have taken place as well as those that have been accepted and planned. The latter includes pre-approved targets for TOO observations and priority C targets whose observations are not guaranteed. This database table is based on information supplied by the XRISM Science Data Center at NASA/GSFC. It is updated automatically on a regular basis. This is a service provided by NASA HEASARC .