HR 8799 is a roughly 30 million-year-old main-sequence star located 129 light years (39 parsecs) away from Earth in the constellation of Pegasus.It has roughly 1.5 times the Sun's mass and 4.9 times its luminosity.Since 1930, Publix has grown from a single store into the largest employee-owned grocery chain in the United States.We are thankful for our customers and associates and continue remaining deeply dedicated to customer service and community involvement, and being a great place to work and shop.
On 13 November 2008, Christian Marois of the National Research Council of Canada's Herzberg Institute of Astrophysics and his team announced they had directly observed three planets orbiting the star with the Keck and Gemini telescopes in Hawaii, A precovery observation of the outer 3 planets was later found in infrared images obtained in 1998 by the Hubble Space Telescope's NICMOS instrument, after a newly developed image-processing technique was applied.
The orbital radii of planets e, d, c and b are 2 to 3 times those of Jupiter, Saturn, Uranus, and Neptune, respectively.
Because of the inverse square law relating radiation intensity to distance from the source, comparable radiation intensities are present at distances These objects are near the upper mass limit for classification as planets; if they exceeded 13 Jupiter masses, they would be capable of deuterium fusion in their interiors and thus qualify as brown dwarfs under the definition of these terms used by the IAU's Working Group on Extrasolar Planets.
Because of this special status, stars like HR 8799 have a very complex spectral type.
The luminosity profile of the Balmer lines in the star's spectrum, as well as the star's effective temperature, best match the typical properties of an F0 V star.
Statistically, for stars hosting a debris disk, the luminosity of this star suggests an age of about 20–150 million years.