We compare the solar and terrestrial bulk elemental compositions. We show that the Sun and Earth share the same refractory elemental abundances, and that, to first order, the Earth is a devolatilized piece of the Sun left over from the Sun’s formation. We discuss the advantages of an aluminium normalization for this comparison over the traditional silicon normalization.

2 In the hallway of the university Wittgenstein asked a colleague: " I've always wondered why for so long people thought that the sun revolved around the earth. " " Why? " said his surprised interlocutor, " well, I suppose it just looks that way. " " Hmm " , retorted Wittgenstein, " and what would it look like if the earth revolved around the sun? " This puzzled the interlocutor.

The flux of neutrino-induced muons at the surface of the Earth is calculated from injection of neutralino annihilation products in the core of the Sun and the Earth. An improved treatment of neutrino propagation through the Sun is performed and the results are presented in an easy-to-use parameterization. For an explicit supersymmetric model, an observable neutralino annihilation signal is demo...

The exact formulae for the capture of WIMPS (weakly interacting massive particles) by a massive body are derived. Capture by the earth is found to be significantly enhanced whenever the WIMP mass is roughly equal to the nuclear mass of an element present in the earth in large quantities. For Dirac neutrino WIMPS of mass 10 to 90 GeV, the capture rate is 10 to 300 times that previously believed....

Ptolemy’s model of the Moon’s motion implied that its distance varies by nearly a factor of two, implying that its angular size should also vary by nearly a factor of two. We present an analysis of 100 naked eye observations of the Moon’s angular size obtained over 1145 days, showing regular variations of at least 3. Thus, ancient astronomers could have shown that a key implication of Ptolemy’s...

Figure 1.2: Sextant is used to measure the angle between star/moon/sun and horizon. Imaging that you are located at the green point in Figure 1.1. It is possible to identify the location by knowing the projected location of the zenith—the point in the sky or celestial sphere directly above an observer—onto the earth surface given time. However, this is challenging because reliably identifying t...

The gravitational acceleration imparted on the solar system’s rocky planets by a putative large body like a planet or a star located at hundreds/thousands AU from the Sun can be considered as a small constant and uniform perturbation A over the characteristic temporal and spatial scales of the inner planetary regions (Pb . 1 yr, r . 1.5 AU). We computed the variation of the longitude of the per...

The gravitational acceleration imparted on a solar system’s rocky planet by a putative large body X like a planet or a star located at hundreds/thousands AU from the Sun can be considered as a small Hooke-type perturbation AX = Kr over the characteristic temporal and spatial scales of the inner planetary regions (Pb . 1 yr, r . 1.5 AU). We computed the variation of the longitude of the periheli...

© 2003 American Institute of Physics, S-0031-9228-0311-020-4 P the most remarkable aspect of the growth in our understanding of the universe is that we understand anything at all. Beyond the obvious regularities of the seasons, the Assyrians noted, as early as 700 BC, that the planets appeared to move in a complex semiregular pattern and that solar eclipses were possible only at the new moon, w...