[ Delta Scuti is the prototype of the Delta Scuti type variable stars. It is a high-amplitude δ Scuti type pulsator with light variations of about 0.15 minutes. The peculiar chemical abundances of this star are similar to those of Am stars.[14]]In 1900, William W. Campbell and William H. Wright used the Mills spectrograph at the Lick Observatory to determine that this star has a variable radial velocity.[23] The {{val|0.19377}}-day period of this variability as well as 0.2 magnitude changes in luminosity demonstrated in 1935 that the variability was intrinsic, rather than being the result of a spectroscopic binary.[24] In 1938, a secondary period was discovered and a pulsation theory was proposed to model the variation.[25] Since then, observation of Delta Scuti has shown that it pulsates in multiple discrete radial and non-radial modes. The strongest mode has a frequency of 59.731 μHz, the next strongest has a frequency of 61.936 μHz, and so forth, with a total of eight different frequency modes now modeled.[26]
The space velocity components of this star in the galactic coordinate system are {{nowrap|[U, V, W]}} = {{nowrap|[–42, –17, –1] km·s−1}}. It is following an orbit through the Milky Way galaxy that has an eccentricity of 0.11, carrying it as close as {{Convert|22.31|kly|kpc|abbr=on|lk=on}} to, and as far as {{Convert|27.59|kly|kpc|abbr=on|lk=off}} from the galactic center.[12] If Delta Scuti maintains its current movement and brightness, it will pass within 10 light-years of the solar system,[28] becoming the brightest star in the sky between {{val|1150000}} and {{val|1330000|u=CE}}. It will reach an apparent magnitude of -1.84, brighter than the current -1.46 of Sirius.[1]
This star has two optical companions. The first is a +12.2 magnitude star that is 15.2 arcseconds from Delta Scuti. The second is a +9.2 magnitude star that is 53 arcseconds away.[30]
Flamsteed did not recognise the constellation Scutum and included several of its stars in Aquila. δ Scuti was catalogued as 2 Aquilae. The Bayer designation δ was assigned by Gould rather than Bayer.[2]
References
1. ^Sky and Telescope, April 1998 (p60), based on computations from Hipparcos mission data.
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