Universe Guide

HomeFactsConstellationsCassiopeia

HD 220842 - HIP115714

HD 220842 is a blue to white star that can be located in the constellation of Cassiopeia. The star can not be seen by the naked eye, you need a telescope to see it. The star has an estimated age of 9.10 Billion of Years but could be as young as 8.00 to 10.10 according to Hipparcos.

HIP115714 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD220842. HD 220842 has at least 1 Extrasolar Planets believed to be in orbit around the star.

Location of HD 220842

The location of the star in the galaxy is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then its eastwards. The Declination is how far north or south the star is compared to the celestial equator and is expressed in degrees. For HD 220842, the location is 23h 26m 37.08 and +56d53`10.3 .

Proper Motion of HD 220842

All stars like planets orbit round a central spot, in the case of planets, its the central star such as the Sun. In the case of a star, its the galactic centre. The constellations that we see today will be different than they were 50,000 years ago or 50,000 years from now. Proper Motion details the movements of these stars and are measured in milliarcseconds. The star is moving 142.07 ± 0.52 miliarcseconds/year towards the north and -89.89 ± 0.73 miliarcseconds/year east if we saw them in the horizon.

Physical Properties (Colour, Temperature, Age, Mass, Radius) of HD 220842

HD 220842 has a spectral type of F8. This means the star is a blue to white star. The star is 7423.00000000 Parsecs from the Galactic Centre or terms of Light Years is 24211.1050251200000000s. The star has a B-V Colour Index of 0.59 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 5,898 Kelvin.

HD 220842 Radius has been calculated as being 1.35 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 941,755.23.km. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 1.42. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures. The star's solar mass is 1.00 times that of the Sun's. The Sun's Mass is 1,989,100,000,000,000,000,000 billion kg. which to calculate using this website is too large. To give idea of size, the Sun is 99.86% the mass of the solar system.

The star's metallicity is -0.170000, this value is the fractional amount of the star that is not Hydrogen (X) or Helium (Y). An older star would have a high metallicity whereas a new star would have a lower one.

The stars age according to Hipparcos data files put the star at an age of about 9.10 Billion years old but could be between 8.00 and 10.10 Billion years old. In comparison, the Sun's age is about 4.6 Billion Years Old.

HD 220842 Apparent and Absolute Magnitudes

HD 220842 has an apparent magnitude of 7.98 which is how bright we see the star from Earth. Apparent Magnitude is also known as Visual Magnitude. If you used the 1997 Parallax value, you would get an absolute magnitude of 4.10 If you used the 2007 Parallax value, you would get an absolute magnitude of 4.00. Magnitude, whether it be apparent/visual or absolute magnitude is measured by a number, the smaller the number, the brighter the Star is. Our own Sun is the brightest star and therefore has the lowest of all magnitudes, -26.74. A faint star will have a high number.

Distance to HD 220842

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 16.73 which gave the calculated distance to HD 220842 as 194.96 light years away from Earth or 59.77 parsecs. It would take a spaceship travelling at the speed of light, 194.96 years to get there. We don't have the technology or spaceship that can carry people over that distance yet.

In 2007, Hipparcos data was revised with a new parallax of 16.03 which put HD 220842 at a distance of 203.47 light years or 62.38 parsecs. It should not be taken as though the star is moving closer or further away from us. It is purely that the distance was recalculated.

The star's Galacto-Centric Distance is 7,423.00 Parsecs or 24,211.11 Light Years. The Galacto-Centric Distance is the distance from the star to the Centre of the Galaxy which is Sagittarius A*.

Source of Information

The source of the information if it has a Hip I.D. is from Simbad, the Hipparcos data library based at the University at Strasbourg, France. Hipparcos was a E.S.A. satellite operation launched in 1989 for four years. The items in red are values that I've calculated so they could well be wrong. Information regarding Metallicity and/or Mass is from the E.U. Exoplanets. The information was obtained as of 12th Feb 2017.

HD 220842 Facts

Alternative Names

Traditional/Proper NameHD 220842
Hipparcos Library I.D.115714
Bonner DurchmusterungBDD+56 3009
Henry Draper Designation220842

Visual Facts

Star Type star
Age9.10 Billion Years Old
Age Range8.00 - 10.10 Billion Years Old
Absolute Magnitude4.10 / 4.00
Visual / Apparent Magnitude7.98
Naked Eye VisibleRequires a 7x50 Binoculars - Ref: Wiki
Right Ascension (R.A.)23h 26m 37.08
Declination (Dec.)+56d53`10.3
Galactic Latitude-4.09 degrees
Galactic Longitude111.51 degrees
1997 Distance from Earth16.73 Parallax (milliarcseconds)
 194.96 Light Years
 59.77 Parsecs
2007 Revised Distance from Earth16.03 Parallax (milliarcseconds)
 203.47 Light Years
 62.38 Parsecs
Galacto-Centric Distance24,211.11 Light Years / 7,423.00 Parsecs
Proper Motion Dec.142.07 ± 0.52 milliarcseconds/year
Proper Motion RA.-89.89 ± 0.73 milliarcseconds/year
B-V Index0.59
Radial Velocity-21.30 ± 0.40 km/s
Iron Abundance-0.27 ± 0.02 Fe/H
Spectral TypeF8
Colour(F) blue to white

Companions (Multi-Star and Exoplanets) Facts

Exoplanet Count1

Estimated Facts

Calculated Effective Temperature5,898 Kelvin
Mass Compared to the Sun1.00
Metallicity-0.17000

Sources and Links

SIMBAD SourceLink

Related Stars


List of Extrasolar Planets orbiting HD 220842


NameStatusMass (Jupiters)Orbital Period (Days)EccentricityDiscoveredSemi-Major AxisPeriastron
Hd 220842 BConfirmed3.18218.4700.40420160.74225.000

Add a Comment


Name:
Email: (Optional)
Comment: