Universe Guide
Search

HD 101917

HD 101917 Facts

  • HD 101917 is a subgiant star that can be located in the constellation of Chamaeleon. The description is based on the spectral class.
  • HD 101917 is not part of the constellation outline but is within the borders of the constellation.
  • Based on the spectral type (K0III/IV) of the star, the star's colour is orange to red .
  • The star can be seen with the naked eye, that is, you don't need a telescope/binoculars to see it.
  • Using the most recent figures given by the 2007 Hipparcos data, the star is 178.33 light years away from us. Distance

HD 101917's Alternative Names

HIP57137 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD101917.

More details on objects' alternative names can be found at Star Names .

Location of HD 101917

The location of the subgiant star in the night sky 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 object is compared to the celestial equator and is expressed in degrees. For HD 101917, the location is 11h 42m 54.53 and -79° 18` 22.9 .

Radial Velocity and Proper Motion of HD 101917

Proper Motion

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 -10.81 ± 0.32 milliarcseconds/year towards the north and 127.06 ± 0.41 milliarcseconds/year east if we saw them in the horizon.

Radial Velocity

The Radial Velocity, that is the speed at which the star is moving away/towards the Sun is 32.50000 km/s with an error of about 0.40 km/s . When the value is negative then the star and the Sun are getting closer to one another, likewise, a positive number means that two stars are moving away. Its nothing to fear as the stars are so far apart, they won't collide in our life-time, if ever.

Physical Properties of HD 101917

HD 101917 Temperature and Colour

Based on the star's spectral type of K0III/IV , HD 101917's colour and type is orange to red subgiant star. The star has a B-V Colour Index of 0.89 which means the star's temperature is about 5,074 Kelvin. The temperature was calculated using information from Morgans @ Uni.edu.

HD 101917 Luminosity

Luminosity is the amount of energy that a star pumps out and its relative to the amount that our star, the Sun gives out. The figure of 9.24 that I have given is based on the value in the Simbad Hipparcos Extended Catalogue at the University of Strasbourg from 2012.

HD 101917 Radius

HD 101917 estimated radius has been calculated as being 3.57 times bigger than the Sun. The Sun's radius is 695,800km, therefore the star's radius is an estimated 2,481,194.95.km. If you need the diameter of the star, you just need to multiple the radius by 2. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 3.500870699206957557346505145. The figure is derived at by using the formula from SDSS rather than peer reviewed papers. It has been known to produce widely incorrect figures.

HD 101917 Apparent and Absolute Magnitudes

HD 101917 has an apparent magnitude of 6.38 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 2.65 If you used the 2007 Parallax value, you would get an absolute magnitude of 2.69. 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 101917

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 17.95000 which gave the calculated distance to HD 101917 as 181.71 light years away from Earth or 55.71 parsecs. If you want that in miles, it is about 1,068,205,016,561,193.77, based on 1 Ly = 5,878,625,373,183.61 miles.

In 2007, Hipparcos data was revised with a new parallax of 18.29000 which put HD 101917 at a distance of 178.33 light years or 54.67 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.

Using the 2007 distance, the star is roughly 11,276,418.38 Astronomical Units from the Earth/Sun give or take a few. An Astronomical Unit is the distance between Earth and the Sun. The number of A.U. is the number of times that the star is from the Earth compared to the Sun. The star's Galacto-Centric Distance is 7,374.00 Parsecs or 24,051.28 Light Years. The Galacto-Centric Distance is the distance from the star to the Centre of the Galaxy which is Sagittarius A*.

Travel Time to HD 101917

The time it will take to travel to this star is dependent on how fast you are going. U.G. has done some calculations as to how long it will take going at differing speeds. A note about the calculations, when I'm talking about years, I'm talking non-leap years only (365 days).

The New Horizons space probe is the fastest probe that we've sent into space at the time of writing. Its primary mission was to visit Pluto which at the time of launch (2006), Pluto was still a planet.

DescriptionSpeed (m.p.h.)Time (years)
Walking429,897,765,862.39
Car120996,592,195.41
Airbus A380736162,487,857.95
Speed of Sound (Mach 1)767.269155,865,887.26
Concorde (Mach 2)1,534.5477,932,842.06
New Horizons Probe33,0003,623,971.62
Speed of Light670,616,629.00178.33

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.

Hide Explanations
Show GridLines

Additional HD 101917 Facts and Figures

Visual Facts


Primary / Proper / Traditional NameHD 101917
Alternative NamesHD 101917, HIP 57137
Spectral TypeK0III/IV
Constellation's Main StarNo
Multiple Star SystemNo / Unknown
Star TypeSubgiant Star
ColourOrange to Red
GalaxyMilky Way
ConstellationChamaeleon
Absolute Magnitude 2.65 / 2.69
Visual / Apparent Magnitude6.38
Naked Eye VisibleYes - Magnitudes
Right Ascension (R.A.)11h 42m 54.53
Declination (Dec.)-79° 18` 22.9
Galactic Latitude-16.87285290 degrees
Galactic Longitude299.65739159 degrees
1997 Distance from Earth17.95000 Parallax (milliarcseconds)
 181.71 Light Years
 55.71 Parsecs
2007 Distance from Earth18.29000 Parallax (milliarcseconds)
 178.33 Light Years
 54.67 Parsecs
 11,276,418.38 Astronomical Units
Galacto-Centric Distance24,051.28 Light Years / 7,374.00 Parsecs
Proper Motion Dec.-10.81000 ± 0.32000 milliarcseconds/year
Proper Motion RA.127.06000 ± 0.41000 milliarcseconds/year
B-V Index0.89
Radial Velocity32.50000 ± 0.40 km/s
Eccentricity0.28510
Semi-Major Axis7793.0000000
Stellar Luminosity (Lsun)9.2400000

Companions (Multi-Star and Exoplanets) Facts


Exoplanet CountNone/Unaware

Estimated Calculated Facts


Radius (x the Sun)3.50
Effective Temperature5,074 Kelvin

Sources and Links


SIMBAD SourceLink

Related Stars


Comments and Questions

There's no register feature and no need to give an email address if you don't need to. All messages will be reviewed before being displayed. Comments may be merged or altered slightly such as if an email address is given in the main body of the comment.

You can decline to give a name which if that is the case, the comment will be attributed to a random star. A name is preferred even if its a random made up one by yourself.

   
x
This website is using cookies. More info. That's Fine