5 Vulpeculae is a single,
[ white-hued star in the northern constellation of ]Vulpecula
Vulpecula is a faint constellation in the northern sky. Its name is Latin for "little fox", although it is commonly known simply as the fox. It was identified in the seventeenth century, and is located in the middle of the Summer Triangle (an ...
.[ It is situated amidst a random concentration of bright stars designated Collinder 399,][ or Brocchi's Cluster. This is a faint star that is just visible to the naked eye with an ]apparent visual magnitude
Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's lig ...
of 5.60.[ Based upon an annual parallax shift of ,][ and will make its closest approach in 2.5 million years at a separation of around .][
This is a young ]A-type main-sequence star
An A-type main-sequence star (A V) or A dwarf star is a main-sequence (hydrogen-burning) star of spectral type A and luminosity class V (five). These stars have spectra defined by strong hydrogen Balmer absorption lines. They measure between ...
with a stellar classification of A0 V.[ It is a rapidly rotating star][ with a ]projected rotational velocity
Stellar rotation is the angular motion of a star about its axis. The rate of rotation can be measured from the spectrum of the star, or by timing the movements of active features on the surface.
The rotation of a star produces an equatorial bulg ...
of 154 km/s.[ The star has an estimated 2.33][ times the mass of the Sun and about 2.7][ times the Sun's radius. It is radiating 34 times the ]Sun's luminosity
The solar luminosity (), is a unit of radiant flux (power emitted in the form of photons) conventionally used by astronomers to measure the luminosity of stars, galaxies and other celestial objects in terms of the output of the Sun.
One nominal ...
from its photosphere at an effective temperature of 8,940 K.[
A warm ]debris disk
A debris disk (American English), or debris disc (Commonwealth English), is a circumstellar disk of dust and debris in orbit around a star. Sometimes these disks contain prominent rings, as seen in the image of Fomalhaut on the right. Debris di ...
was detected by the Spitzer Space Telescope at a temperature of , orbiting 13 Astronomical units
The astronomical unit (symbol: au, or or AU) is a unit of length, roughly the distance from Earth to the Sun and approximately equal to or 8.3 light-minutes. The actual distance from Earth to the Sun varies by about 3% as Earth orbits ...
from the host star.[ Although this finding has not been directly detected, the emission signature indicates the disk is in the form of a thin ring. The emission displays weak transient absorption features that are indicative of kilometer-sized exocomets that are undergoing evaporation as they approach the host star.][ These absorption features have been observed to vary on time scales of hours, days, or months.][
]
References
External links
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{{DEFAULTSORT:Vulpeculae, 05
A-type main-sequence stars
Vulpecula
Durchmusterung objects
Flamsteed objects
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