Determinations Of Stellar Parallax Research Articles

Using Smartphone Camera Technology to Explore Stellar Parallax: Method, Results, and Reactions

Abstract The use of a smartphone, with both still and video capabilities, to develop the concepts surrounding stellarparallax is described. The hands-on activities generate useful discussion amongst high school students. Reactionsof both students and teachers are presented. 1. INTRODUCTION Stellar parallax is a concept that is dealt with infrequently in the high school classroom other than by qualitativeconsideration of stereoscopic parallax and argument by analogy, such as that outlined in Zeilik (1998). The mostcommon approach involves students being asked to view their finger held at arm’s length and first viewing itfrom one eye and then the other. They “see” their finger’s apparent movement against the background of theroom. Following this qualitative approach, the unit of distance used in astronomy is introduced from adefinitional point of view: “The parsec is the distance of an object at which the angle subtended by a baselineequal to the distance between the Earth and the Sun is one second of arc.” This description is quite abstract,however, and it is unlikely that students will really get a conceptual feel for the idea of a parsec as a distancemeasure from an abstract mathematical statement. As the parsec is the fundamental unit of distance inastronomy, it is important that students have some strong insight to what this unit actually means (Marin 2010).We assessed a sample of diagrams available on the internet using a Google Image search. The first 50 diagramspresented from the search term “Stellar Parallax” were examined. Out of the 50 diagrams, 18 showed thealternative conception that all stars in the night sky “wobble” in a straight line, a further 20 showed the specialcase, where the star is on the ecliptic equator where they actually do wobble in a straight line, and a further 7 hadmajor faults. Only five out of the 50 diagrams accurately represented the relationship between the Earth–Sunorbit and the parallactic ellipse in the sky. That is to say, of this sample of 50 diagrams, only 10% could beconsidered to be scientifically accurate and a complete conceptual representation of stellar parallax.The experimental determination of stellar parallax is seldom dealt with in the science classroom because theparallactic angle is so small. Students have little, if any, idea of how astronomers collect their data because theydo not normally conduct the experiment first successfully executed by Bessel in 1838 in measuring the parallax

An improvement of the plate constant method in the determination of stellar parallaxes

We introduce self-dependence of reference stars in the method of plate constants, which can be used to identify and reject reference stars with unusually large proper motion or parallax, thereby improving the result. A specific example (BD + 70°68) is worked out. The configuration of reference stars is also discussed.

On the timing of an interstellar communication

By considering prominent events that are observable from both earth and nearby stellar systems it is possible to establish common clocks that may be useful in estimating arrival times for signals of intelligent extraterrestrial origin. The geometry and statistics of a timing strategy are developed together with quantitative estimates of its effectiveness and limits on its application. Effectiveness is measured by comparing the timing strategy with one randomized in time. Limitations arise from inaccuracies inherent in the determination of stellar parallaxes and result in standard deviations of the order of weeks to months for time estimates. The problem can be alleviated by choosing clocks close to Sender in angular distance. Signal opportunities for several nearby sun-like stars are calculated using the bright Nova Cygni 1975 as a clock.

On the Photometric Use of Plates Taken for the Determination of Stellar Parallax

On the Photometric Use of Plates Taken for the Determination of Stellar Parallax

The Photographic Determination of Stellar Parallaxes with the 60- and 100-INCH Reflectors. Nineteenth Series.

The Photographic Determination of Stellar Parallaxes with the 60- and 100-INCH Reflectors. Nineteenth Series.

The Photographic Determination of Stellar Parallaxes with the 60- and I00-INCH Reflectors.

The Photographic Determination of Stellar Parallaxes with the 60- and I00-INCH Reflectors.

A list of test objects for trigonometric determinations of stellar parallax

A list of test objects for trigonometric determinations of stellar parallax

Effects of Atmospheric Dispersion upon Determinations of Stellar Parallax

Effects of Atmospheric Dispersion upon Determinations of Stellar Parallax

The Effect of the Second-Order Terms in Differential Aberration on Determinations of Stellar Parallax

The Effect of the Second-Order Terms in Differential Aberration on Determinations of Stellar Parallax

The Influence of Atmospheric Dispersion on Photographic Determinations of Stellar Parallax

The Influence of Atmospheric Dispersion on Photographic Determinations of Stellar Parallax

Photographic Determinations of Stellar Parallax 1

THE determination of stellar parallaxes by photography has shown a striking improvement in recent years, and the results obtained with the Yerkes refractor are of the highest order of excellence. Two of the precautions observed in this and similar series of measures are the taking of all th6 plates at small hour-angles, so as to minimise the effect of unequal atmospheric dispersion in the stars, arid the reduction of the magnitude of the parallax star to equality with file comparison stars. This latter precaution is necessary, since any inequality in the driving will have a different effect on the images of objects that differ much in brightness. The usual way of effecting this is by rotating a screen in the form of a sector of a circle in front of the brighter image. By altering the angle of the sector, any desired diminution of light may be obtained.

Errata [On evidences of systematic variation in recent longer series of determinations of stellar parallax

Errata [On evidences of systematic variation in recent longer series of determinations of stellar parallax

On evidences of systematic variation in recent longer series of determinations of stellar parallax

On evidences of systematic variation in recent longer series of determinations of stellar parallax

Photographic determinations of stellar parallax made with the Yerkes refractor. VII.

Photographic determinations of stellar parallax made with the Yerkes refractor. VII.

Photographic determinations of stellar parallax made with the Yerkes refractor. VI.

Photographic determinations of stellar parallax made with the Yerkes refractor. VI.

Photographic determinations of stellar parallax made with the Yerkes refractor. V.

Photographic determinations of stellar parallax made with the Yerkes refractor. V.

Photographic determinations of stellar parallax made with the Yerkes refractor. IV.

Photographic determinations of stellar parallax made with the Yerkes refractor. IV.

Photographic determinations of stellar parallax made with the Yerkes refractor. III.

Photographic determinations of stellar parallax made with the Yerkes refractor. III.

Determinations of Stellar Parallax from Photographs made at the Cambridge Observatory. Introductory Paper

Determinations of Stellar Parallax from Photographs made at the Cambridge Observatory. Introductory Paper

The Oxford Photographic Determinations of Stellar Parallax. Reply to Professor Turner

The Oxford Photographic Determinations of Stellar Parallax. Reply to Professor Turner