Title:                    Adoption of MS v2.0
Persons responsible:      A. Kemball (akemball@nrao.edu)
                          M. Wieringa (Mark.Wieringa@atnf.CSIRO.AU)
Originator of proposal:   A. Kemball (akemball@nrao.edu)
Exploder targeted:        aips2-astro-design, aips2-synthesis
Time table:
    Date of issue:           1998 December 21      Done
    Comments due:            1998 December 28      Done
    Revised proposal:        1998 December 31      Done. Delayed due to
                                                   volume of comments.
    Final comments due:      1999 February 11      Done.
    Decision date:           1999 February 12      Done


Summary of revisions to the original change proposal:

1. Policy 

Expanded or clarified:
  a) Use of Measures (p.6).
  b) Relative indexing (p.6).
  c) Time and intervals (p.6).
  d) Non-standard columns (p.6).
  e) Definition of UVW, WEIGHT in MAIN (p.28).
  f) Definition of REFERENCE_DIR in FIELD table (p.35).
  g) Definition of SOURCE_MODEL in SOURCE table (p.16).

2. Revisions

  a) New, optional PHASE_ID column in MAIN (p.10).
  b) New, TIME_CENTROID in MAIN (p.12).
  c) Release date added to OBSERVATION table (p.16).
  d) UVW3 removed from MAIN (p.26).
  e) FREQ_OFFSET is indexed on baseline, rather than antenna (p.37).
  f) Revisions in the POINTING table, with expanded descriptions (p.40).
  g) Add TSKY, TSKY_SPECTRUM and TSKY_FLAG to SYSCAL table (p.19).
  
3. Typographic errors corrected, or minor revisions.

  a) ANTENNA_TYPE changed to TYPE in ANTENNA table.
  b) FLAG_COMMAND change to COMMAND in FLAG table.
  c) OBJECT_ID default in HISTORY table corrected.
  d) PASS_NO changed to PASS_ID in the PROCESSOR table, and made optional.
  e) CHAN_FREQ_REF changes to MEAS_FREQ_REF in SPECTRAL_WINDOW table.
  f) TANT/TSKY units dimensionless in SYSCAL table.
  g) Recommended units for PRESSURE in WEATHER are now hPa.
  h) OBS_SCHEDULE_TYPE changed to SCHEDULE_TYPE in OBSERVATION table.
  i) OBS_SCHEDULE changed to SCHEDULE in OBSERVATION table.
  j) OBS_LOG changed to LOG in OBSERVATION table.
  k) OBS_DATE changed to TIME_RANGE in OBSERVATION table.

Statement of goals:

 To adopt MS format v2.0, for reasons outlined below. This was deliberately 
postponed until after beta 3.0, but it is now an appropriate time to 
proceed with adoption.

Proposed changes:
 
 Now documented in AIPS++ Note 229.

Expected impact:

 These changes been made in a trial area by Mark Wieringa and will be
made available on his home page, and summarized for others to review 
the impact on data fillers. Our assessment is that the changes will 
have modest impact.

Proposed documentation changes:

 Check in of this document to the AIPS++ Notes series.

Attachment:

 See AIPS++ Note 229.