Space-Time Reference Frames

  • Pierre Léna
  • François Lebrun
  • François Mignard
Part of the Astronomy and Astrophysics Library book series (AAL)

Abstract

An essential part of astrophysical observation consists in measuring the positions of astronomical objects and in dating events. Obtaining the photometric magnitudes of the emitted radiation is not enough; the position of its source must also be determined to great accuracy, for spatial resolutions of the order of several tenths of a millisecond of arc can now be attained, and this tendency is certain to continue (cf. Chap. 4). In terms of sensitivity, detectors can now measure the characteristics of phenomena whose time of variation is less than one millisecond. And further, extremely accurate time scales are required for space travel and exploration of specific sites in the solar system.

Keywords

Quartz Microwave Radar Sine Recent Epoch 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Pierre Léna
    • 1
  • François Lebrun
    • 2
  • François Mignard
    • 3
  1. 1.Observatoire de Paris-MeudonUniversité de Paris VIIMeudon Principal CedexFrance
  2. 2.Commissariat à l’Energie Atomique/SaclayDSM/DAPNIA/SApGif-sur-Yvette CedexFrance
  3. 3.Observatoire de la Côte d’AzurCentre de Recherche en Géodynamique et AstrométrieGrasseFrance

Personalised recommendations