Search results
Results from the WOW.Com Content Network
At least two methods have been used to measure the distance to the Sombrero Galaxy. The first method relies on comparing the measured fluxes from the galaxy's planetary nebulae to the known luminosity of planetary nebulae in the Milky Way. This method gave the distance to the Sombrero Galaxy as 29 ± 2 Mly (8,890 ± 610 kpc). [28]
The astronomical unit is too small to be convenient for interstellar distances, where the parsec and light-year are widely used. The parsec (parallax arcsecond) is defined in terms of the astronomical unit, being the distance of an object with a parallax of 1″. The light-year is often used in popular works, but is not an approved non-SI unit ...
The astronomical unit of length is now defined as exactly 149 597 870 700 meters. [4] It is approximately equal to the mean Earth–Sun distance. It was formerly defined as that length for which the Gaussian gravitational constant (k) takes the value 0.017 202 098 95 when the units of measurement are the astronomical units of length, mass and ...
At the present time the proper distance equals the comoving distance since the cosmological scale factor has value one: () =. The proper distance represents the distance obtained as if one were able to freeze the flow of time (set d t = 0 {\displaystyle dt=0} in the FLRW metric) and walk all the way to a galaxy while using a meter stick. [ 2 ]
[16] [17] [18] An astronomical unit, or AU, is the distance from Earth to the Sun, which is approximately 150 billion meters (93 million miles). [19] Small Solar System objects are classified by their orbits: [20] [21] Main Asteroid belt (main belt), between Mars and Jupiter, in near circular orbit, 2.2 to 3.2 AU
This is a list of known galaxies within 3.8 megaparsecs (12.4 million light-years) of the Solar System, in ascending order of heliocentric distance, or the distance to the Sun. This encompasses about 50 major Local Group galaxies, and some that are members of neighboring galaxy groups , the M81 Group and the Centaurus A/M83 Group , and some ...
One particularly distant body is 90377 Sedna, which was discovered in November 2003.It has an extremely eccentric orbit that takes it to an aphelion of 937 AU. [2] It takes over 10,000 years to orbit, and during the next 50 years it will slowly move closer to the Sun as it comes to perihelion at a distance of 76 AU from the Sun. [3] Sedna is the largest known sednoid, a class of objects that ...
For the giant planets, the "radius" is defined as the distance from the center at which the atmosphere reaches 1 bar of atmospheric pressure. [ 11 ] Because Sedna and 2002 MS 4 have no known moons, directly determining their mass is impossible without sending a probe (estimated to be from 1.7x10 21 to 6.1×10 21 kg for Sedna [ 12 ] ).