radius Comparison Table

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radius comparison table

Subject is named after has unit has proposal date has uncertainty has definition has equation has symbol has value has proposer is a unit of

Bohr radius Niels Bohr 1928 0.0000000019 × 10^-10 m A unit of length based on the radius of the first Bohr orbit of hydrogen 1. a₀ 0.5291772083 × 10^-10 m Hartree length

classical electron radius 0.00000031 × 10^-15 m r_e 2.817940285 × 10^-15 m

gravitational radius length unit The radius which an object should have in order that light emitted from its surface just ceases to escape from its surface.

Holmberg radius length unit The radius of an external galaxy at which the surface brightness is 26.6 mag arcsec^-2. This criterion was developed by Holmberg in 1958 to estimate the actual dimensions of the major and minor axes of a galaxy without regard to its orientation in space.

Hubble radius length unit The radius of the observable universe (). c/H > 10²⁷ cm

Larmor radius length unit The radius of the circular orbit that a charged particle describes transverse to a magnetic field.

solar radius length unit A unit of length based on radius of Sun length

velocity-of-light radius length unit The radius of a rotating neutron star at which the rotational velocity of the plasma approaches the velocity of light. (also called velocity-of-light cylinder)

Next length: semimajor axis Up: length Previous length: Planck length

Subject	is named after	has unit	has proposal date	has uncertainty	has definition	has equation	has symbol	has value	has proposer	is a unit of
Bohr radius	Niels Bohr		1928	0.0000000019 × 10^-10 m	A unit of length based on the radius of the first Bohr orbit of hydrogen 1.		a₀	0.5291772083 × 10^-10 m	Hartree	length
classical electron radius				0.00000031 × 10^-15 m			r_e	2.817940285 × 10^-15 m
gravitational radius		length unit			The radius which an object should have in order that light emitted from its surface just ceases to escape from its surface.
Holmberg radius		length unit			The radius of an external galaxy at which the surface brightness is 26.6 mag arcsec^-2. This criterion was developed by Holmberg in 1958 to estimate the actual dimensions of the major and minor axes of a galaxy without regard to its orientation in space.
Hubble radius		length unit			The radius of the observable universe ().		c/H	> 10²⁷ cm
Larmor radius		length unit			The radius of the circular orbit that a charged particle describes transverse to a magnetic field.
solar radius		length unit			A unit of length based on radius of Sun					length
velocity-of-light radius		length unit			The radius of a rotating neutron star at which the rotational velocity of the plasma approaches the velocity of light. (also called velocity-of-light cylinder)