Chapter

Stars and Double Stars

January 1996

In book: Unveiling the Universe (pp.157-193)

Authors:

The stars do not appear to be of equal brightness. About 125 BC, Hipparchus made the first classification of stars according to their brightnesses. His predecessor, Aristarchus (310–230 BC), had proved that the Sun, Moon and planets are at varying distances from the Earth, and that they do not move equally far from the Earth against a crystal sphere, as Aristotle had stated.

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ResearchGate has not been able to resolve any references for this publication.

Chapter

Ptolemy’s Cosmology

January 2001

Asger Aaboe

The Ptolemaic system has long been in common use as the name for the cosmological scheme that was eventually replaced by the Copernican. It consists of seven nested spherical shells, one for the Sun, one for the Moon, and one for each of the five planets, all surrounded by the sphere of the fixed stars. All of this revolves once a day about a central, stationary Earth, while Sun, Moon, and ... [Show full abstract] planets move appropriately and much more slowly, each within its own sphere. This scheme is most often represented graphically by its intersection with the plane of the ecliptic (the Sun’s orbit)—it then becomes a system of nested annuli—for the planets and the Moon are always close to this plane.

Chapter

Modeling the Space Environment

January 1978

James Wertz

Chapter 4 described models of the appearance, shape, and atmosphere of the Earth. This chapter is concerned with modeling properties of the spacecraft environment that are relevant to attitude determination and control. Sections 5.1 and 5.2 describe the magnetic and gravitational fields of the Earth, although many of the modeling procedures can be extended to other planets as well. Section 5.3 ... [Show full abstract] discusses the interplanetary medium known as the solar wind. The remaining three sections discuss models of the position of various objects needed for attitude determination—the spacecraft itself, the Sun, the Moon, the planets, and the stars.

Presentation

Full-text available

Astronomy for Precise Positioning and Stellarium

June 2020

Sher Bahadur Gurung

Astronomy is the study of the sun, moon, stars, planets, comets, gas, galaxies, gas, dust and other non-Earthly bodies and phenomena. More generally, astronomy studies everything that originates outside Earth’s atmosphere. It studies the Universe as a whole. So the regular observation of celestial body support precise positioning.

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Chapter

14. Aristotle’s World-Picture

October 2000

Jonathan Barnes

According to ‘Aristotle’s World-Picture’, Aristotle was a remarkable scientist and a profound philosopher, but it was as a philosopher-scientist that he excelled. The elements of the sublunary world are four: earth, air, fire, and water. Our earth is naturally at the centre of the universe. Beyond it lie the moon, the sun, the planets, and the fixed stars, attached to a series of concentric ... [Show full abstract] spheres. Aristotle argued that the physical universe is spatially finite but temporally infinite. The celestial spheres, and the bodies they carry, are quintessential and divine; but they are moving divinities. Beyond them, incorporeal and outside the universe, is the changeless source of change: the ‘unmoved mover’.

Article

Computing Orbital Viewing Parameters

February 1990

Charles Petruzzo

QUIKVIS computer program calculates times during orbit around Earth when geometric requirements satisfied for observing celestial objects. Observed objects fixed (e.g. stars) or moving (Sun, Moon, planets). Useful for preflight analysis by those needing information on availability of celestial objects to be observed. Performs two types of analyses: One used when specific objects known, other when ... [Show full abstract] targets unknown and potentially useful regions of sky must be identified. Results useful in selecting candidate targets, examining effects of observation requirements, and doing gross assessments of effects of right ascension of ascending node (RAAN) of orbit. Written in FORTRAN 77.

Chapter

The New Vision of the Cosmos

September 2023

Daniele L. R. Marini

The view of the Cosmos had become incompatible with the new observations. Aristotle, on the one hand, conceived the Cosmos organized in a geocentric view, and on the other, he divided celestial phenomena between sublunar and those that took place beyond the sphere of the moon. The Cosmos was seen as an invariable entity in which the sun, moon, and planets moved with regularity, and nothing about ... [Show full abstract] it ever changed. The sublunar phenomena concerned everything that took place on the earth and in the atmosphere, and to them, according to the Aristotelians, belonged meteors and comets, but in-depth study of comets and new stars had demonstrated the inconsistency of these theories.

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System design of a mission to detect Earth-sized planets in the inner orbits of solar-like stars

April 1996 · Journal of Geophysical Research Atmospheres

A point design for a mission to detect Earth-sized planets in the inner orbits of solar-like stars is described. The observing technique is based upon continuously and simultaneously monitoring 5000 solar-like stars for brightness changes that would be caused by planets transiting their star. Detection of periodic transits of the same amplitude and duration provides for a robust method of ... [Show full abstract] discovery. The instrument would consist of a 1-m Schmidt telescope with an array of charge-coupled devices (CCDs) filling the 12° field of view. The instrument would be placed in a halo orbit about the L2 Lagrange point, where its viewing would not be obscured at any time by the Sun, Earth, or Moon.

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Article

Full-text available

Prehistoric Skyscrapers

September 2019

Jacques Coulardeau

The stones are pointing to the sky and yet they prove nothing, except that these men believed there was something to point at in the sky, first of all plenty of stars and planets and the stones were like the map of these celestial bodies. The stones had their feet and roots well planted in the earth and that proves nothing, except that these men were able to transport the stones and to erect them ... [Show full abstract] with their bare hands. The stones were aligned on the stars and planets and that proves nothing except that they knew the sun, the moon, Venus and some others had cyclical minds and perambulating trajectories. These men liked these cyclical natural and cosmic events and they understood that this was their real master on earth, even if Venus was not Venus but only the Morning Star or the Evening Star. Publication Date: 2019 Publication Name: Medium.com

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Chapter

The Zodiacal Light And Gegenschein

January 1973

The projection of the Earth’s orbit on the celestial sphere, the ecliptic, delineates the apparent annual path of the Sun against the star background. The other major members of the solar system - the planets and their moons - move within a few degrees of the ecliptic as a consequence of their intrinsic orbital motions combined with that of the Earth.

Article

Through Space and Time

July 2009

James Jeans

1. The earth; 2. The air; 3. The sky; 4. The moon; 5. The planets; 6. The sun; 7. The stars; 8. The nebulae.

Chapter

Chapter Three

January 2004

This chapter discusses that the Moon, other planets, and stars are not the size they appear to be. It illustrates that the Earth's shadow is neither funnel-like, nor cylindrical. The notion that the Moon too is not the size that it appears to be is caused by the eclipse of the Sun. That is because the Sun is eclipsed only when the Moon passes under it, and obstructs the line of sight; a solar ... [Show full abstract] eclipse, in other words, is a condition affecting not the Sun, but the line of sight. The Moon does appear large, in fact equal in size to the Earth, and larger than the other heavenly bodies, when in reality it is smaller than they, since it is closest to the Earth of all the heavenly bodies, and thought to be located right at the junction of the air and the aether.

Chapter

On the Likenesses of the Creatures

November 2020

Chapter 7 describes how, following Ahriman’s attack on creation, Ohrmazd consigned the forms of the primordial cow and the first man, Gayōmard, to the stars, moon, and sun. The positive role assigned to the sun and moon here contradicts their negative nature, along with that of the five planets, described in chapter 2. The chapter also mentions the compositions of different types of stars, made ... [Show full abstract] up of water, earth, and plant essence.

Stars and Double Stars

Abstract

No full-text available

Recommended publications

Ptolemy’s Cosmology

Modeling the Space Environment

Astronomy for Precise Positioning and Stellarium

14. Aristotle’s World-Picture

Computing Orbital Viewing Parameters

The New Vision of the Cosmos

System design of a mission to detect Earth-sized planets in the inner orbits of solar-like stars

Prehistoric Skyscrapers

The Zodiacal Light And Gegenschein

Through Space and Time

Chapter Three

On the Likenesses of the Creatures