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Celestial coordinates

The telescope was yoke mounted in a rocket fixed azimuth-elevation system. The payload was spin balanced about the longitudinal or roll axis, which is coincident with the sensor azimuth axis. A fine error guidance sensor, or star tracker, actively held the telescope azimuth axis fixed in celestial coordinates. Telescope was deployed to the desired elevation angle and the payload rotated about the roll axis. The sensor was stepped through an angle slightly less than the total field of view each time the payload rotated 360°. Thus a contiguous sector on the celestial sphere was mapped out. [Pg.16]

Euler s proof of the least action principle for a single particle (mass point in motion) was extended by Lagrange (c. 1760) to the general case of mutually interacting particles, appropriate to celestial mechanics. In Lagrange s derivation [436], action along a system path from initial coordinates P to final coordinates Q is defined by... [Pg.9]

The excess at each position in the celestial sky is computed by counting the number events from that sky position and subtracting the estimated background. For a given point the background is computed from data collected at the same local detector coordinates (0,4>), but at a different time, so that the celestial angles of the background event sample do not overlap with the source position under consideration. The method of Li and Ma[10] is used to compute the final probability of the observed excess or deficit. [Pg.246]

The findings of Newton and Descartes developed into a beautiful model of space-time that served both microphysics and celestial mechanics convincingly well until the end of the nineteenth century. This scheme recognized the three-dimensional aspect of space that extends uniformly along three orthogonal coordinate axes to infinity. Independent of space, the inexorable flow of universal time kept all motion in step. All events unfolded against the... [Pg.300]

Celestite [7759-02-6] (syiL, celestine) [from the Latm, caelestis, meaning celestial] (ICSD 28055 and PDF 5-593) SrSO, M= 183.6836 47.70 wt.% Sr 17.46 wt.%S 34.84 wt.% 0 Coordinence Sr(6), S(4) (Sulfetes, diromates, molybdates, and tungstates) Orthorhombic a = 835.9 pm b= 535.2 pm c= 686.6 pm (Z = 4) P.G. mmm S.G. P2,nma Barite type Biaxial (-t) a= 1.622 1.624 r= 1.631 S= 0.009 2y=5i Dispersion moderate 3-3.5 3970 Habit tabular, radiated fibrous, crystalline, massive, granular. Color colorless, bluish white, yellowish white, or reddish white. Diaphaneity transparent to translucent. Luster vitreous (ie., glassy). Streak white. Qeavage (001) perfect, (210) good. Fracture uneven to conchoidal, brittle. Chemical decomposed at 1607 C Occurrence sedimentary rocks. [Pg.815]

The most celebrated problem in celestial mechanics is the so-called three-body problem. First elucidated by Lagrange, this problem focuses on the determination of the allowed class of periodic motions for a massless particle orbiting a binary system. In this case, the motion is determined by the gravitational and centrifugal accelerations and also the Coriolis force. A closed form analytic solution is possible in only one case, that of equal masses in a circular orbit. This so-caUed restricted three-body problem can be specified by the curves of constant potential, also called the zero velocity surfaces. Consider a binary with a coplanar orbit for the third mass. In this case, a local coordinate system (C, r]) is defined as centered at (a, 1 — a) so that the equations of motion are... [Pg.23]


See other pages where Celestial coordinates is mentioned: [Pg.26]    [Pg.26]    [Pg.714]    [Pg.10]    [Pg.714]    [Pg.295]    [Pg.26]    [Pg.26]    [Pg.714]    [Pg.10]    [Pg.714]    [Pg.295]    [Pg.308]    [Pg.345]    [Pg.28]    [Pg.68]    [Pg.717]    [Pg.895]    [Pg.899]    [Pg.18]   
See also in sourсe #XX -- [ Pg.26 ]




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