
This is a view from within the Polaris triple star system. The North Star, Polaris A is a bright supergiant variable star.
Just above Polaris is a small companion, Polaris Ab, which is 2 billion miles from Polaris. Much farther away, near the top of the illustration, is the wide companion Polaris B. Polaris B is located approximately 240 billion miles from Polaris A. The two companion stars are the same temperature as Polaris A, but are dwarf stars.
The wide companion star is visible in small telescopes. It was first noticed by William Herschel in 1780. The close companion, Polaris Ab was known to exist from measurements of a wobble in Polaris, caused by the gravitational tug of its companion, but has only been seen directly now using Hubble.
Credits
Credit: NASA, ESA, G. Bacon (STScI)About The Object | |
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Object Name | Polaris, Alpha Ursae Minoris, North Star |
About The Object | |
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Object Name | A name or catalog number that astronomers use to identify an astronomical object. |
Object Description | The type of astronomical object. |
R.A. Position | Right ascension – analogous to longitude – is one component of an object's position. |
Dec. Position | Declination – analogous to latitude – is one component of an object's position. |
Constellation | One of 88 recognized regions of the celestial sphere in which the object appears. |
Distance | The physical distance from Earth to the astronomical object. Distances within our solar system are usually measured in Astronomical Units (AU). Distances between stars are usually measured in light-years. Interstellar distances can also be measured in parsecs. |
Dimensions | The physical size of the object or the apparent angle it subtends on the sky. |
About The Data | |
Data Description |
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Instrument | The science instrument used to produce the data. |
Exposure Dates | The date(s) that the telescope made its observations and the total exposure time. |
Filters | The camera filters that were used in the science observations. |
About The Image | |
Image Credit | The primary individuals and institutions responsible for the content. |
Publication Date | The date and time the release content became public. |
Color Info | A brief description of the methods used to convert telescope data into the color image being presented. |
Orientation | The rotation of the image on the sky with respect to the north pole of the celestial sphere. |