Skip to main content Accessibility help

We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.

Close cookie message
×
  1. Home
  2. Journals
  3. Proceedings of the International Astronomical Union
  4. Transactions of the International Astronomical Union
  5. Volume 25
Journal Home
Refine listing

Refine listing

Access:
Publication date:

Actions for selected content:

Select all | Deselect all
  • View selected items
  • Export citations
  • Download PDF (zip)
  • Save to Kindle
  • Save to Dropbox
  • Save to Google Drive

Save Search

You can save your searches here and later view and run them again in "My saved searches".

Please provide a title, maximum of 40 characters.
Cancel
×
< Back to all issues

Transactions of the International Astronomical Union, Volume 25 - 2007

Contents

Page 1 of 7

Other

  • Preface

  • Hans Rickman
  • Published online by Cambridge University Press:
    25 April 2016, p. 1
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

  • Preface

  • Oddbjørn Engvold
  • Published online by Cambridge University Press:
    25 April 2016, pp. xii-xiii
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

Meeting Report

  • Chapter I: Twenty Fifth General Assembly Inaugural Ceremony

  • Published online by Cambridge University Press:
    25 April 2016, pp. 1-10
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

Divisions and their Commissions

Meeting Report

  • Chapter II: Twenty Fifth General Assembly

  • Franco Pacini
  • Published online by Cambridge University Press:
    25 April 2016, pp. 11-27
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

Divisions and their Commissions

Meeting Report

  • Chapter III: Resolutions of the General Assembly

  • Published online by Cambridge University Press:
    25 April 2016, pp. 29-33
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

Divisions and their Commissions

Meeting Report

  • Chapter IV: Report of the Executive Committee 2000-2003

  • Published online by Cambridge University Press:
    25 April 2016, pp. 35-53
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

Divisions and their Commissions

Chapter V: Reports of Divisions, Commissions, and Working Groups

  • Division I: Fundamental Astronomy (Astronomie Fondamentale)

  • Nicole Capitaine
  • Published online by Cambridge University Press:
    25 April 2016, pp. 55-64
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

  • Commission 4: Ephemerides (Ephemerides)

  • Toshio Fukushima
  • Published online by Cambridge University Press:
    25 April 2016, pp. 65-66
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

Divisions and their Commissions

  • Commission 31: Time: (L’heure)

  • G. Petit, D.N. Matsakis, D.C. Backer, G. Beutler, T. Fukushima, S.M. Leschiutta, E. Proverbio, G.R. Qi, C. Veillet, G.M.R. Winkler, Z.C. Zhai
  • Published online by Cambridge University Press:
    25 April 2016, pp. 69-72
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

  • The relative frequency stability and the accuracy of atomic time scales, like International Atomic Time TAI, is now of order 1 × 10-15 thanks to progresses in clock technology and in clock comparison techniques. Cold atom primary Cs standards have a stated accuracy of 1 × 10-15 and a stability in the 10-16 region. Other cold atom clocks provide even better prospects, as well as clocks based on trapped ions. Frequencies based on optical and microwave transitions can now be compared with a similar or even better uncertainty thanks to femtosecond comb technology. Clock comparison techniques based on GPS (see http://maia.usno.navy.mil/gpst.html), or on dedicated Two Way technology provide adequate performance when averaging data over one or a few days, and should be improved to accompany the progresses of clocks.

    Since 1999, a number of organizations initiated a review on the future of the UTC system (insertion of leap seconds between TAI and UTC to keep |UT1 – UTC| < 0.9s). Several working groups have been initiated, notably by the International Telecommunications Union (Special Rapporteur Group (SRG) in the Working Party 7A), by the International Union of Radio Science, and by the IAU following Resolution B2(2000). No immediate conclusion may be foreseen but a consensus should be reached over the next triennium.

Chapter V: Reports of Divisions, Commissions, and Working Groups

  • Commission 7: Celestial Mechanics Mechaniques Celeste

  • John D. Hadjidemetriou
  • Published online by Cambridge University Press:
    25 April 2016, pp. 67-68
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

Divisions and their Commissions

Chapter V: Reports of Divisions, Commissions, and Working Groups

  • Commission 8: Astrometry (Astrométrie)

  • I. Platais
  • Published online by Cambridge University Press:
    25 April 2016, pp. 69-74
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

Divisions and their Commissions

Chapter V: Reports of Divisions, Commissions, and Working Groups

  • Commission 19: Rotation of the Earth: (Rotation De La Terre)

  • Nicole Capitaine
  • Published online by Cambridge University Press:
    25 April 2016, pp. 75-77
    • Article
      • You have access
    • PDF
    • Export citation
    • NASA ADS Abstract Service

Page 1 of 7