Theory 
Speeds in the Universe| CONTENT - A list of the speeds reached by objects in the Universe. A tutorial in our series 'Advanced Studies in Astronomy' |
Most of the Universe is in motion. Some objects are reaching tremendous speeds, as the upper limit for any speed in the Universe is the speed of light, at 186,000 miles per second (300,000 km/s). Such high speeds however are not necessarily perceived as such by nearby dwellers or remote observers. When at the surface of the Earth we barely can imagine that we are on a sphere which is moving at 67,000 mph (108,000 km/h) around the Sun. On the other hand, this is a sign of the vastness of the cosmos. (speeds given by increasing order)
The interstellar medium is a mix of molecular clouds, cold and warm gases, regions of electrically charged hydrogen, and more. The light (from the ultraviolet to the infrared) from stars shining throughout the history of the Universe forms a remnant glow called the 'extragalactic background light' or EBL, a cosmic fog which may constitute a barrier for some wavelengths, like gamma rays for example. When a gamma ray encounters usual starlight, it transforms into an electron and a positron and is lost to further observation. Ten billion photons from everywhere in the Universe make it Earth at any given second. Stardust grains originating from supernovae roved the Galaxy for millions of years as they were bombarded by high-energy cosmic radiation and shock waves from their supernovae and survived he harsh environment of deep space, were found in meteorites on Earth. Many of the silicates were amorphous with a wide range of chemical compositions. High-energy X-rays coming from a chorus of millions of black holes, fill the entire sky, a phenomenon astronomers call the cosmic X-ray background. Some gamma rays may reach nearly 50 trillion electron volts (TeV) as the energy of visible light ranges from about 2 to 3 electron volts only. From planetary magnetospheres and stars to primordial structures, turbulent magnetic fields are ubiquitous in the Universe. They play a dramatic role in energetic events such as triggering violent energy release through magnetic reconnection and coronal heating
| Object, Phenomenon | Speed in mph | Speed in km/h |
|---|---|---|
| Mercury rotating | 0.72 | 1.1 |
| Earth rotating | 320 | 500 |
| Sun rotating | 1,380 | 2,200 |
| a Mars orbiter | 7,000 | 11,300 |
| Jupiter rotating | 9,000 | 14,400 |
| Shuttle in orbit | 17,300 | 27,800 |
| A 150-foot wide NEO grazing the Earth | 17,400 | 27,900 |
| Speed needed to put a satellite in orbit | 19,000 | 30,000 |
| Saturn orbiting the Sun | 22,000 | 35,000 |
| a comet | 23,000 | 37,000 |
| Pionner 10 (fastest planetary probe, leaving Earth) | 32,400 | 52,100 |
| A 5-ft wide bolid falling through Earth's atmosphere | 33,500 | 54,000 |
| Planetary probe (average en route) | 35,000 | 56,000 |
| Asteroids and comets slamming into the Moon | 35,800 | 57,600 |
| Voyager 1 (current speed at the solar system's boundaries) | 40,250 | 64,800 |
| A 10-kg, 8-inch wide meteor burn-descending into the Earth's atmosphere | 42,500 | 68,400 |
| The Sun with the solar system heading in the local medium towards constellation of Hercules, the Heroe | 44,750 | 72,000 |
| Interstellar dust grain speeding through the solar system at the distance of Saturn's system, which is fast enough to avoid being trapped inside by the gravity of the Sun and planets | over 45,000 | over 72,000 |
| New Horizons (speed once accelerated by a gravity-assisted flyby at Jupiter; original speed was of 43,000 mph -69,200 km/h) | 52,000 | 83,600 |
| A star expelled from its former companion which turned supernova | 54,000 | 86,900 |
| Sun's proper speed relative to its proximate stellar environment | 56,000 | 90,000 |
| Maximum speed of micrometeorites hitting Moon's surface, as they create the regolith | 62,000 | 100,000 |
| Earth orbiting the Sun | 67,000 | 108,000 |
| Geminids shooting stars | 80,000 | 126,000 |
| Pioneer 10 (after Jupiter' gravity boost) | 82,000 | 132,000 |
| Mercury orbiting the Sun | 107,000 | 170,000 |
| A star ejected from the cluster where it was born | 124,000 | 200,000 |
| A expanding Wolf-Rayet nebula | 136,700 | 220,000 |
| Orionids shooting stars | 150,000 | 238,000 |
| The NASA's Juno mission before reaching Jupiter, which sets the record for a planetery mission's speed in the solar system | 165,000 | 265,500 |
| Speed of a next-generation, ion-thrusted, nuclear powered spacecraft like Prometheus | 200,000 | 322,000 |
| Record speed of a spacecraft established by NASA's Parker solar probe as it was the closest proble passing to the Sun | 213,000 | 340,000 |
| Jets emanating from a newly born star | 200,000-300,000 | 322,000-483,000 |
| A runaway massive star expelled from its birth star cluster | 250,000 (can reach 2 million) | 400,000 (can reach 3.21 million) |
| A evaporating atmosphere at a exoplanet as pushed away by a flare of its parent star's | 300,000 | 480,000 |
| Protostars with streamers of gas and dust ejected into interstellar space due to a collision between two protostars in a cluster | 335,612 | 540,000 |
| Solar system with the Sun orbiting the Galaxy | 500,000 | 828,000 |
| Galaxy M86 moving in the Virgo Cluster | 543,000 | 873,687 |
| Massive clumps of intergalactic cold gas careening toward the supermassive black hole in a galaxy’s core | 621,504 | 1,000,000 |
| Two pulsars orbiting each other at a distance of 500,000 mi (800,000 km) | 670,000 | 1,080,000 |
| Nova's debris expanding | 700,000 | 1,126,300 |
| The high velocity cloud Smith's Cloud moving about our Milky Way Galaxy | 700,000 | 1,126,300 |
| A sungrazing comet passing at perihelion | 828,000 | 1,332,252 |
| The rotation of a 300 million solar masses galactic black hole within 26 light-years of the galaxy's center | 880,000 | 1,400,000 |
| Galactic winds circulating between galaxies | 894,775 | 1,440,000 |
| 'Hypervelocity stars' shooting out of the Milky Way Galaxy as being ejected by interactions with the Milky Way's supermassive black hole | 1 million | 1.6 million |
| Two white dwarfs orbiting each other at a distance of 50,000 mi (80,000 km) | over 1 million | over 1.6 million |
| Two stars orbiting at 50,000 miles (80,000 km) from each other as they create gravitational waves | over 1 million | over 1.6 million |
| A galaxy plunging into a galaxy cluster | 1.4 million (or 2 million) | 2.3 million (or 3.2 million) |
| A comet to be dilapidated by the Sun in its last moments before dispartion | 1.44 million | 2.31 million |
| The solar wind | 1.5 million | 2.4 million |
| A star expelled from its home galaxy, or a 'runaway star' through the gravitational strength of a passage near a supermassive black hole | 1.5 million | 2.4 million |
| Blue, young stars orbiting close to M31 super-massive black hole | 2.2 million | 3.5 million |
| A spiral galaxy interacted by its galaxy cluster's gravity | 2.2 million | 3.5 million |
| Speed of sound in the hot gas of some areas in the Coma Cluster | ab. 2.5 million | ab. 4 million |
| A star turned a neutron star ejected during a supernova event | 3-6 million | 4.6-9.6 million |
| A neutron, or a pulsar star at the center of a supernova remnant, as tossed out by the explosion of the supernova | million | million |
| A galaxy moving inside a galaxy cluster expanding | several million | several million |
| A supermassive, galactic black hole kicked off after a merger between two galaxies due to gravitational waves resulting from the black holes merger | several million | several million |
| A supernova remnant expanding | 4-6 million | 7.2-9.6 million |
| A black hole resulting from a black holes merger in certain conditions during a galaxy merger, and expelled from the new galactic center by gravitational waves | 4.7 million | 7.6 million |
| A black hole resulting from a galactic black holes' merger expelled from the merged galaxies | 6 million | 9.6 million |
| Winds blowing off a stellar-mass black hole's accretion disk, either direction up or down from the plane | 20 million | 32 million |
| Ejected layers in a supernova event | 22.3 million | 36 million |
| A planet teared from its star, or 'hypervelocity planet,' through the gravitational strength of a passage near a supermassive black hole | 30 million (more averagely 8 million) | 48 million (more averagely 12.8 million) |
| Blobs of matter orbiting a galactic supermassive black hole | ab. 67 million | ab. 100 million |
| Jets shooting from a black hole pulling matter from a companion star | 175 million | 282 million |
| A giant dust smudge orbiting just beyond the event horizon of the supermassive black hole at the center of our Milky Way Galaxy | 30 percent the speed of light | 30 percent the speed of light |
| Galactic cosmic rays zipping through space | half the speed of light or more | half the speed of light or more |
| Speed on their orbit of two galactic black holes merging, during last orbits before merging | more than half the speed of light | more than half the speed of light |
| Jets emanating from a gamma-ray burst (GRB) | 670 million (which means 99.9999 percent of the speed of light) | 1.09 billion |
| Light | 671 million | 1.1 billion |
