The Astronomical Unit now

  title={The Astronomical Unit now},
  author={Erland Myles Standish},
  journal={Proceedings of the International Astronomical Union},
  pages={163 - 179}
  • E. Standish
  • Published 1 June 2004
  • Physics
  • Proceedings of the International Astronomical Union
The Astronomical Unit is one of the most basic units of astronomy: the scale of the solar system. Yet its long and colorful history is sprinkled liberally with incorrect descriptions and mis-quoted definitions – today as much as ever. Over the last half century, the accuracy of the au determinations has improved dramatically: optical (triangulation) methods have given way to modern electronic observations, high-speed computers, and dedicated efforts to improve planetary ephemerides. Typical… 
A unified phenomenological model for Solar System anomalies
  • L. Acedo
  • Physics
    Astrophysics and Space Science
  • 2019
The improvement of ephemeris models to unprecedented levels of accuracy and the analysis of radiometric data for the planets, as well as Lunar laser ranging, have revealed some inconsistencies
The astronomer E. V. Pitjeva, by analyzing with the EPM2008 ephemerides a large number of planetary observations including also two years (2004–2006) of normal points from the Cassini spacecraft,
Solar Mass Loss, the Astronomical Unit, and the Scale of the Solar System
The radiative and particulate loss of mass by the Sun, -9.13*10^-14 Solar masses per year or more causes the orbits of the planets to expand at the same rate, and their periods to lengthen at twice
Gravitational Anomalies in the Solar System
Mindful of the anomalous perihelion precession of Mercury discovered by Le Verrier in the second half of the nineteenth century and its successful explanation by Einstein with his General Theory of
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Given a solar luminosity LAr = 0.75L0 at the beginning of the Archean 3.8 Ga ago, where L0 is the present-day one, if the heliocentric distance, r, of the Earth was rAr = 0.956r0, the solar
The subject of this paper is the empirically determined anomalous secular increases of the astronomical unit, of the order of some cm yr−1, and of the eccentricity of the lunar orbit, of the order of
Secular increase of the astronomical unit and perihelion precessions as tests of the Dvali–Gabadadze–Porrati multi-dimensional braneworld scenario
An unexpected secular increase of the astronomical unit, the length scale of the Solar System, has recently been reported by three different research groups (Krasinsky and Brumberg, Pitjeva,
A comment on the possibility of testing the Dvali-Gabadadze-Porrati gravity model with the outer planets of the Solar System
The multidimensional braneworld gravity model by Dvali, Gabadadze and Porrati was primarily put forth to explain the observed acceleration of the expansion of the Universe without resorting to dark
On the secular recession of the Earth-Moon system as an azimuthal gravitational phenomenon
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submitted to Cel
  • Communication of IAA RAN
  • 2001
Well, quite, there's your problem. So it's important to get the concept clear, if youre talking to people who haven't followed the story right through from the
  • 1950
Don Kurtz: No, what's causing the astronomical unit to increase? What's the physical cause of the increase?
    Something I would like to see (if I could talk you into producing it) would be a nice map of one orbit of the Earth, with the Earth and the Sun in a inertial frame
      Myles Standish: I'm sorry, the question is?
        It took me three decades to figure this thing out!
          Myles Standish: I'm sorry, the question is? Marilyn Head: It was really just a comment. You know the minor planet occultations
            Oh! The occultations of asteroids? Marilyn Head: Yes
              No, I would say 7 ± 2. Now, I know that Dr Pitjeva has put out to another significant figure, so maybe that's significant
                Or, the occultation of a star by an asteroid