Gravitational and Related Constants for Accurate Space Navigation. The paper first compares the Gaussian gravitational constant, k s , and the astronomical unit with the cgs value of G and the meter, showing tha
. This is very small by astronomical standards, but is still pretty large. It’s around a third of the mass of the Earth, and would correspond to around 1,000,000,000,000,000,000,000elephants. Sadly, it is not expected that material ejected from neutron stars would directly turn into ...
Gravitational microlensing (including pixel-lensing) is among the most promising techniques if we are interested to find Earth-like planets at distances about a few astronomical units from the host star. View article Journal 2009, New Astronomy ReviewsAlexander F. Zakharov Mini review Proceedings of...
Although there had been a slight sense of disappointment in the astronomical community a few years ago because lensing had not yet solved all the big problems of astrophysics (e.g. determination of the Hubble constant; nature of dark matter; physics/size of quasars), this feeling has apparentl...
There are, in addition, other quantities that can be constructed to be compared with astronomical observations. In order to take the simplest situation for observation, one can assume that the first relativistic image Θ10 can be resolved from the others, that are collectively packed at Θ∞0 ...
dates back to the work of Einstein in 19361. In this pioneering work he considered the case where both the lens and the magnified background source were stars in our Galaxy. Einstein concluded that the deflection angles were too small to be resolved with astronomical instruments. It was Zwicky...
where F is the gravitational force between two point masses, M1 and M2; d is the distance between M1 and M2; G is the universal gravitational constant, usually taken as 6.670 × 1011 m3/(kg)(s2) or 6.670 × 10−8 in centimeter–gram–second units. According to Newton's second law ...
So far, we have mainly focussed on tests of GR on spatial scales of several astronomical units (the size of the solar system), and on scales of 300,000 km (the typical separation between two neutron stars). We conclude this section on experimental tests of gravity by mentioning the existen...
Explanatory Supplement to the Astronomical Almanac. University Science Books, p. 316 (Table 5.8.1) (1992) Famaey, B., McGaugh, S.S.: Modified Newtonian dynamics (MOND): observational phenomenology and relativistic extensions. Living Rev. Relativ.15, 10 (2012) ...
Tantalizing evidence for the existence of gravity waves came from astronomical observations of a binary pulsar designated 1913+16. The rate at which the two neutron stars in the binary rotate around each other changes in a manner that is consistent with the emission of gravity waves. The ...