Canopus or Alpha Carinae (Alp Car) is the brightest naked eye star in the constellation Carina. With an apparent magnitude of -0.62, Canopus is the 2nd brightest star in the entire sky (see: 50 Brightest Stars ). Its absolute magnitude is -5.53 and its distance is 313 light years. The Equinox J2000 equatorial coordinates are RA = 06h 23m 57.1s, Dec = -52° 41' 45".
Canopus has a spectral type of F0Ib, a surface temperature of 7350° Kelvin and a luminosity 13,600 times the Sun. It has a mass of 8.5 solar masses and a diameter 65 times the Sun.
The image above shows the uncropped view of Canopus (North is up) through the Takahashi E-180 Astrograph.
Canopus is a supergiant of spectral type F and appears essentially white to the naked eye. With a luminosity of 13,600 Suns, the most intrinsically bright star within approximately 700 light years of the Solar System. From a hypothetical distance of 1 Astonomical Unit (Earth's distance from the Sun), Canopus would have an apparent magnitude of -37 (the Sun is -27.5). Canopus appears less bright than Sirius in our sky only because Sirius is much closer to Earth (8.6 light years).
The diameter of Canopus has been measured at 0.6 astronomical units or 65 times that of the Sun. If it were placed at the center of the Solar System, it would extend three-quarters of the way to Mercury. An Earth-like planet would have to lie three times the distance of Pluto for its star to appear the same size in the sky as our own Sun.
Canopus is a strong source of X-rays, which are probably produced by its corona, magnetically heated to around 15 million degrees Kelvin. It is a member of the Scorpius-Centaurus Association, a group of stars which share similar origins.
- Object: Canopus
- Other Names: Alpha Carinae, HR2326, HD45348, HIP30438
- Object Type: bright star
- Object Data: Apparent Magnitude = -0.62, Absolute Magnitude = -5.53, distance = 313 light years
- Object Position (Equinox J2000): RA = 06h 23m 57.1s, Dec = -52° 41' 45", Constellation = Carina
- Date/Time: 2011 Nov 02 at 10:12:50 UTC
- Location: Bifrost Astronomical Observatory, Portal, AZ
- Mount: Astro-Physics 1200GTO
- Telescope: Takahashi Epsilon 180 Hyperbolic Astrograph
- Camera: Canon EOS 550D (Rebel T2i) (modified with a Baader UV/IR filter)
- Field of View: 1.70° x 2.56° at 1.7 arc-sec/pixel (web version: 10.0 arc-sec/pixel)
- Exposure: 2 x 240s, f/2.8, ISO 800
- File Name: Canopus-01w.jpg
- Processing (Adobe Camera Raw): Graduated Filter, Vignetting Correction, Noise Reduction, White Balance, Curves
- Processing (Photoshop CS5): Average Images, Curves, Noise Reduction
- Original Image Size: 3454 × 5179 pixels (17.9 MP); 11.5" x 17.3" @ 300 dpi
- Rights: Copyright 2011 by Fred Espenak. All Rights Reserved. See: Image Licensing.