Photometric parallax: Difference between revisions

Revision as of 20:48, 17 November 2006

Latest revision as of 18:34, 20 July 2025

(29 intermediate revisions by 17 users not shown)

Line 1:

{{Short description|Astronomy technique}}

{{wikinews|Huge star cluster discovered in neighbourhood of Milky Way}}

The '''photometric parallax method''' is a method of data analysis used in [[astronomy]] that uses the colours and apparent brightnesses of stars to infer their distances. It was used by the [[Sloan Digital Sky Survey]] to discover the [[Virgo super star cluster]].

The '''photometricPhotometric parallax method''' is a methodmeans ofto datainfer analysisthe useddistances inof [[astronomystar]]s thatusing uses thetheir colours and apparent brightnesses of stars to infer their distances. It was used by the [[Sloan Digital Sky Survey]] to discover the [[Virgo super star cluster]].

Parallax method is only good for nearby stars (< 50pc or ~163ly)

1 Parsec (pc) is the distance associated with a parallax angle of 1" (" = arcseconds)

Assuming that a star is on the main sequence, the star's [[absolute magnitude]] can be determined based on its color. Once the absolute and [[apparent magnitude]]s are known, the distance to the star can be determined by using the [[distance modulus]]. It does not actually employ any measurements of [[parallax]] and can be considered a misnomer.

To calculate distance of a nearby star using the Parallax Method:

Unlike the [[stellar parallax]] method, the photometric parallax method can be used to estimate the distances of stars over 10 kpc away, at the expense of much more limited accuracy for individual measurements.

d= 1/Parallax angle

==See also==

d will turn out as a Parsec (pc)

*[[Parallax in astronomy]]

*[[Spectroscopic parallax]]

*[[Dynamical parallax]]

== References ==

* {{cite journal |author=Mario Juric |display-authors=etal |title=The Milky Way Tomography with SDSS |year=2008 |doi=10.1086/523619 |journal=The Astrophysical Journal |volume=673 |issue=2 |pages=864–914 |arxiv=astro-ph/0510520|bibcode=2008ApJ...673..864J |s2cid=11935446 }}

[[Category:AstronomyAstrometry]]

To give the distance in Lightyears (ly), use d= 3.26/Parallax angle

To

{{astronomy-stub}}

== References ==

* {{cite paper|title=The Milky Way Tomography with SDSS|author=Mario Juric, Zeljko Ivezic, Alyson Brooks, Robert H. Lupton, David Schlegel, Douglas Finkbeiner, Nikhil Padmanabhan, Nicholas Bond, Constance M. Rockosi, Gillian R. Knapp, James E. Gunn, Takahiro Sumi, Donald Schneider, J.C. Barentine, Howard J. Brewington, J. Brinkmann, Masataka Fukugita, Michael Harvanek, S.J. Kleinman, Jurek Krzesinski, Dan Long, Eric H. Neilsen, Jr., Atsuko Nitta, Stephanie A. Snedden, Donald G. York|url=http://www.arxiv.org/abs/astro-ph/0510520|date=2005-10-18}}

[[Category:Astronomy]]