Astrophysics (Index)About

A-type star

(A, A-class star)
(star with spectral characteristics of around 8500 K)

An A-type star is a star within the A-class, a spectral class indicating stars with strong hydrogen absorption lines, a white color and a surface temperature in the range of 7,500 to 10,000 K. The spectral energy distribution peaks in the visible/near ultraviolet range. Main sequence stars of this class are on the order of 2 solar masses, 2 times solar radius and 10 times as bright as the Sun. Such main sequence stars burn their hydrogen on the order of a billion years. Characteristics of A-type main sequence stars:

1.5-2.4absolute magnitude(visual)
5-25bolometric luminosity(solar)
1.5-4 billion yearsmain-sequence lifetime

Example A-type stars are Canopus (a supergiant), HR 8799, Sirius A and Vega.

(star type,spectral class)
Further reading:
145nm2.1PHz8.6eVbeginA-type star
290nm1.1PHz4.3eVendA-type star

Referenced by pages:
Am star
Ap star
Balmer jump (BJ)
BA supergiant
Balmer-break galaxy (BBG)
Be star
Beta Pictoris b (β Pic b)
convection zone
globular cluster (GC)
Herbig AeBe star (HAeBe)
Hyades Cluster
Lambda Boötis star (λ Boo)
Markarian galaxy (Mkn)
Morgan classification
red giant
RR Lyrae variable (RRL)
star formation rate (SFR)
spectral class
SS 433
stellar demographics
TW Hydrae association (TWA)