Fastest orbiting asteroid found in our solar system
By Ashley Strickland, CNN

Updated 3:20 PM ET, Tue August 24, 2021
This artist's concept illustration shows what the luminous blue variable star in the Kinman Dwarf galaxy may have looked like before it mysteriously disappeared.
Photos: Wonders of the universe
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29 of 56
This is an artist's illustration of a supermassive black hole and its surrounding disk of gas. Inside this disk are two smaller black holes orbiting one another. Researchers identified a flare of light suspected to have come from one such binary pair soon after they merged into a larger black hole.
Photos: Wonders of the universe
Show Caption
30 of 56
This image, taken from a video, shows what happens as two objects of different masses merge together and create gravitational waves.
Photos: Wonders of the universe
Show Caption
31 of 56
This is an artist's impression showing the detection of a repeating fast radio burst seen in blue, which is in orbit with an astrophysical object seen in pink.
Photos: Wonders of the universe
Show Caption
32 of 56
Fast radio bursts, which make a splash by leaving their host galaxy in a bright burst of radio waves, helped detect "missing matter" in the universe.
Photos: Wonders of the universe
Show Caption
33 of 56
A new type of explosion was found in a tiny galaxy 500 million light-years away from Earth. This type of explosion is referred to as a fast blue optical transient.
Photos: Wonders of the universe
Show Caption
34 of 56
Astronomers have discovered a rare type of galaxy described as a "cosmic ring of fire." This artist's illustration shows the galaxy as it existed 11 billion years ago.
Photos: Wonders of the universe
Show Caption
35 of 56
This is an artist's impression of the Wolfe Disk, a massive rotating disk galaxy in the early universe.
Photos: Wonders of the universe
Show Caption
36 of 56
A bright yellow "twist" near the center of this image shows where a planet may be forming around the AB Aurigae star. The image was captured by the European Southern Observatory's Very Large Telescope.
Photos: Wonders of the universe
Show Caption
37 of 56
This artist's illustration shows the orbits of two stars and an invisible black hole 1,000 light-years from Earth. This system includes one star (small orbit seen in blue) orbiting a newly discovered black hole (orbit in red), as well as a third star in a wider orbit (also in blue).
Photos: Wonders of the universe
Show Caption
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This illustration shows a star's core, known as a white dwarf, pulled into orbit around a black hole. During each orbit, the black hole rips off more material from the star and pulls it into a glowing disk of material around the black hole. Before its encounter with the black hole, the star was a red giant in the last stages of stellar evolution.
Photos: Wonders of the universe
Show Caption
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This artist's illustration shows the collision of two 125-mile-wide icy, dusty bodies orbiting the bright star Fomalhaut, located 25 light-years away. The observation of the aftermath of this collision was once thought to be an exoplanet.
Photos: Wonders of the universe
Show Caption
40 of 56
This is an artist's impression of the interstellar comet 2I/Borisov as it travels through our solar system. New observations detected carbon monixide in the cometary tail as the sun heated the comet.
Photos: Wonders of the universe
Show Caption
41 of 56
This rosette pattern is the orbit of a star, called S2, around the supermassive black hole at the center of our Milky Way galaxy.
Photos: Wonders of the universe
Show Caption
42 of 56
This is an artist's illustration of SN2016aps, which astronomers believe is the brightest supernova ever observed.
Photos: Wonders of the universe
Show Caption
43 of 56
This is an artist's illustration of a brown dwarf, or a "failed star" object, and its magnetic field. The brown dwarf's atmosphere and magnetic field rotate at different speeds, which allowed astronomers to determine wind speed on the object.
Photos: Wonders of the universe
Show Caption
44 of 56
This artist's illustration shows an intermediate-mass black hole tearing into a star.
Photos: Wonders of the universe
Show Caption
45 of 56
This is an artist's impression of a large star known as HD74423 and its much smaller red dwarf companion in a binary star system. The large star appears to pulsate on one side only, and it's being distorted by the gravitational pull of its companion star into a teardrop shape.
Photos: Wonders of the universe
Show Caption
46 of 56
This is an artist's impression of two white dwarfs in the process of merging. While astronomers expected that this might cause a supernova, they have found an instance of two white dwarf stars that survived merging.
Photos: Wonders of the universe
Show Caption
47 of 56
A combination of space and ground-based telescopes have found evidence for the biggest explosion seen in the universe. The explosion was created by a black hole located in the Ophiuchus cluster's central galaxy, which has blasted out jets and carved a large cavity in the surrounding hot gas.
Photos: Wonders of the universe
Show Caption
48 of 56
This new ALMA image shows the outcome of a stellar fight: a complex and stunning gas environment surrounding the binary star system HD101584.
Photos: Wonders of the universe
Show Caption
49 of 56
NASA's Spitzer Space Telescope captured the Tarantula Nebula in two wavelengths of infrared light. The red represents hot gas, while the blue regions are interstellar dust.
Photos: Wonders of the universe
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A white dwarf, left, is pulling material off of a brown dwarf, right, about 3,000 light-years from Earth.
Photos: Wonders of the universe
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This image shows the orbits of the six G objects at the center of our galaxy, with the supermassive black hole indicated with a white cross. Stars, gas and dust are in the background.
Photos: Wonders of the universe
Show Caption
52 of 56
After stars die, they expel their particles out into space, which form new stars in turn. In one case, stardust became embedded in a meteorite that fell to Earth. This illustration shows that stardust could flow from sources like the Egg Nebula to create the grains recovered from the meteorite, which landed in Australia.
Photos: Wonders of the universe
Show Caption
53 of 56
The former North Star, Alpha Draconis or Thuban, is circled here in an image of the northern sky.
Photos: Wonders of the universe
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Galaxy UGC 2885, nicknamed the "Godzilla galaxy," may be the largest one in the local universe.
Photos: Wonders of the universe
Show Caption
55 of 56
The host galaxy of a newly traced repeating fast radio burst acquired with the 8-meter Gemini-North telescope.
Photos: Wonders of the universe
Show Caption
56 of 56
Meet the fastest asteroid in our solar system, which zips around the sun every 113 days. This artist's rendering shows the asteroid 2021 PH27 (top right) and Mercury (below) orbiting the sun.
Photos: Wonders of the universe
Show Caption
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A ghostly set of  X-ray rings were found around a black hole with a companion star. These rings are created by light echoes.
Photos: Wonders of the universe
Show Caption
2 of 56
This image, taken with the Atacama Large Millimeter/submillimeter Array in Chile, shows the PDS 70 system 400 light-years away. This planetary system is still forming and still in the process of being formed. One of the planets in the system has a moon-forming disk around it.
Photos: Wonders of the universe
Show Caption
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This image shows supernova 2018zd (pictured as the large white dot on the right), a new type of supernova called an electron capture. To the left is the galaxy NGC 2146.
Photos: Wonders of the universe
Show Caption
4 of 56
This image from the STARFORGE simulation shows the "Anvil of Creation," a giant gas cloud with individual stars forming inside of it.
Photos: Wonders of the universe
Show Caption
5 of 56
Astronomers used NASA's Chandra X-ray Observatory to study the supernova remnant Cassiopeia A and discovered titanium, shown in light blue, blasting out of it. The colors represent other elements detected, like iron (orange), oxygen (purple), silicon (red) and magnesium (green).
Photos: Wonders of the universe
Show Caption
6 of 56
The supermassive black hole at the center of the M87 galaxy, the first to ever be imaged, can now be seen in polarized light. Swirling lines reveal the magnetic field near the edge of the black hole.
Photos: Wonders of the universe
Show Caption
7 of 56
This image from the Sloan Digital Sky Survey shows the galaxy J0437+2456, which includes a supermassive black hole at its center that appears to be moving.
Photos: Wonders of the universe
Show Caption
8 of 56
This artist's impression shows how the distant quasar P172+18 and its radio jets may have looked 13 billion years ago. The light from the quasar has taken that long to reach us, so astronomers observed the quasar as it looked in the early universe.
Photos: Wonders of the universe
Show Caption
9 of 56
This image shows the vicinity of the Tucana II ultrafaint dwarf galaxy, captured by the SkyMapper telescope.
Photos: Wonders of the universe
Show Caption
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These images show two giant radio galaxies found with using the MeerKAT telescope. The red in both images shows the radio light being emitted by the galaxies against a background of the sky as it is seen in visible light.
Photos: Wonders of the universe
Show Caption
11 of 56
This artist's conception of quasar J0313-1806 depicts it as it was 670 million years after the Big Bang. Quasars are highly energetic objects at the centers of galaxies, powered by black holes and brighter than entire galaxies.
Photos: Wonders of the universe
Show Caption
12 of 56
Shown here is a phenomenon known as zodiacal light, which is caused by sunlight reflecting off tiny dust particles in the inner solar system.
Photos: Wonders of the universe
Show Caption
13 of 56
This artist's impression of the distant galaxy ID2299 shows some of its gas being ejected by a "tidal tail" as a result of a merger between two galaxies.
Photos: Wonders of the universe
Show Caption
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This diagram shows the two most important companion galaxies to the Milky Way: the Large Magellanic Cloud (left) and the Small Magellanic Cloud. It was made using data from the European Space Agency Gaia satellite.
Photos: Wonders of the universe
Show Caption
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The Blue Ring Nebula is thought to be a never-before-seen phase that occurs after the merger of two stars. Debris flowing out from the merger was sliced by a disk around one of the stars, creating two cones of material glowing in ultraviolet light.
Photos: Wonders of the universe
Show Caption
16 of 56
The red supergiant star Betelgeuse, in the constellation of Orion, experienced unprecedented dimming late in 2019. This image was taken in January using the European Southern Observatory's Very Large Telescope.
Photos: Wonders of the universe
Show Caption
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This is an infrared image of Apep, a Wolf-Rayet star binary system located 8,000 light-years from Earth.
Photos: Wonders of the universe
Show Caption
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An artist's illustration, left, helps visualize the details of an unusual star system, GW Orionis, in the Orion constellation. The system's circumstellar disk is broken, resulting in misaligned rings around its three stars.
Photos: Wonders of the universe
Show Caption
19 of 56
This is a simulation of two spiral black holes that merge and emit gravitational waves.
Photos: Wonders of the universe
Show Caption
20 of 56
This artist's illustration shows the unexpected dimming of the star Betelgeuse.
Photos: Wonders of the universe
Show Caption
21 of 56
This extremely distant galaxy, which looks similar to our own Milky Way, appears like a ring of light.
Photos: Wonders of the universe
Show Caption
22 of 56
This artist's interpretation shows the calcium-rich supernova 2019ehk. The orange represents the calcium-rich material created in the explosion. Purple reveals gas shed by the star right before the explosion.
Photos: Wonders of the universe
Show Caption
23 of 56
The blue dot at the center of this image marks the approximate location of a supernova event which occurred 140 million light-years from Earth, where a white dwarf exploded and created an ultraviolet flash. It was located close to tail of the Draco constellation.
Photos: Wonders of the universe
Show Caption
24 of 56
This radar image captured by NASA's Magellan mission to Venus in 1991 shows a corona, a large circular structure 120 miles in diameter, named Aine Corona.
Photos: Wonders of the universe
Show Caption
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When a star's mass is ejected during a supernova, it expands quickly. Eventually, it will slow and form a hot bubble of glowing gas. A white dwarf will emerge from this gas bubble and move across the galaxy.
Photos: Wonders of the universe
Show Caption
26 of 56
The afterglow of short gamma ray burst that was detected 10 billion light-years away is shown here in a circle. This image was taken by the Gemini-North telescope.
Photos: Wonders of the universe
Show Caption
27 of 56
This Hubble Space Telescope image shows NGC 7513, a barred spiral galaxy 60 million light-years away. Due to the expansion of the universe, the galaxy appears to be moving away from the Milky Way at an accelerate rate.
Photos: Wonders of the universe
Show Caption
28 of 56
This artist's concept illustration shows what the luminous blue variable star in the Kinman Dwarf galaxy may have looked like before it mysteriously disappeared.
Photos: Wonders of the universe
Show Caption
29 of 56
This is an artist's illustration of a supermassive black hole and its surrounding disk of gas. Inside this disk are two smaller black holes orbiting one another. Researchers identified a flare of light suspected to have come from one such binary pair soon after they merged into a larger black hole.
Photos: Wonders of the universe
Show Caption
30 of 56
This image, taken from a video, shows what happens as two objects of different masses merge together and create gravitational waves.
Photos: Wonders of the universe
Show Caption
31 of 56
This is an artist's impression showing the detection of a repeating fast radio burst seen in blue, which is in orbit with an astrophysical object seen in pink.
Photos: Wonders of the universe
Show Caption
32 of 56
Fast radio bursts, which make a splash by leaving their host galaxy in a bright burst of radio waves, helped detect "missing matter" in the universe.
Photos: Wonders of the universe
Show Caption
33 of 56
A new type of explosion was found in a tiny galaxy 500 million light-years away from Earth. This type of explosion is referred to as a fast blue optical transient.
Photos: Wonders of the universe
Show Caption
34 of 56
Astronomers have discovered a rare type of galaxy described as a "cosmic ring of fire." This artist's illustration shows the galaxy as it existed 11 billion years ago.
Photos: Wonders of the universe
Show Caption
35 of 56
This is an artist's impression of the Wolfe Disk, a massive rotating disk galaxy in the early universe.
Photos: Wonders of the universe
Show Caption
36 of 56
A bright yellow "twist" near the center of this image shows where a planet may be forming around the AB Aurigae star. The image was captured by the European Southern Observatory's Very Large Telescope.
Photos: Wonders of the universe
Show Caption
37 of 56
This artist's illustration shows the orbits of two stars and an invisible black hole 1,000 light-years from Earth. This system includes one star (small orbit seen in blue) orbiting a newly discovered black hole (orbit in red), as well as a third star in a wider orbit (also in blue).
Photos: Wonders of the universe
Show Caption
38 of 56
This illustration shows a star's core, known as a white dwarf, pulled into orbit around a black hole. During each orbit, the black hole rips off more material from the star and pulls it into a glowing disk of material around the black hole. Before its encounter with the black hole, the star was a red giant in the last stages of stellar evolution.
Photos: Wonders of the universe
Show Caption
39 of 56
This artist's illustration shows the collision of two 125-mile-wide icy, dusty bodies orbiting the bright star Fomalhaut, located 25 light-years away. The observation of the aftermath of this collision was once thought to be an exoplanet.
Photos: Wonders of the universe
Show Caption
40 of 56
This is an artist's impression of the interstellar comet 2I/Borisov as it travels through our solar system. New observations detected carbon monixide in the cometary tail as the sun heated the comet.
Photos: Wonders of the universe
Show Caption
41 of 56
This rosette pattern is the orbit of a star, called S2, around the supermassive black hole at the center of our Milky Way galaxy.
Photos: Wonders of the universe
Show Caption
42 of 56
This is an artist's illustration of SN2016aps, which astronomers believe is the brightest supernova ever observed.
Photos: Wonders of the universe
Show Caption
43 of 56
This is an artist's illustration of a brown dwarf, or a "failed star" object, and its magnetic field. The brown dwarf's atmosphere and magnetic field rotate at different speeds, which allowed astronomers to determine wind speed on the object.
Photos: Wonders of the universe
Show Caption
44 of 56
This artist's illustration shows an intermediate-mass black hole tearing into a star.
Photos: Wonders of the universe
Show Caption
45 of 56
This is an artist's impression of a large star known as HD74423 and its much smaller red dwarf companion in a binary star system. The large star appears to pulsate on one side only, and it's being distorted by the gravitational pull of its companion star into a teardrop shape.
Photos: Wonders of the universe
Show Caption
46 of 56
This is an artist's impression of two white dwarfs in the process of merging. While astronomers expected that this might cause a supernova, they have found an instance of two white dwarf stars that survived merging.
Photos: Wonders of the universe
Show Caption
47 of 56
A combination of space and ground-based telescopes have found evidence for the biggest explosion seen in the universe. The explosion was created by a black hole located in the Ophiuchus cluster's central galaxy, which has blasted out jets and carved a large cavity in the surrounding hot gas.
Photos: Wonders of the universe
Show Caption
48 of 56
This new ALMA image shows the outcome of a stellar fight: a complex and stunning gas environment surrounding the binary star system HD101584.
Photos: Wonders of the universe
Show Caption
49 of 56
NASA's Spitzer Space Telescope captured the Tarantula Nebula in two wavelengths of infrared light. The red represents hot gas, while the blue regions are interstellar dust.
Photos: Wonders of the universe
Show Caption
50 of 56
A white dwarf, left, is pulling material off of a brown dwarf, right, about 3,000 light-years from Earth.
Photos: Wonders of the universe
Show Caption
51 of 56
This image shows the orbits of the six G objects at the center of our galaxy, with the supermassive black hole indicated with a white cross. Stars, gas and dust are in the background.
Photos: Wonders of the universe
Show Caption
52 of 56
After stars die, they expel their particles out into space, which form new stars in turn. In one case, stardust became embedded in a meteorite that fell to Earth. This illustration shows that stardust could flow from sources like the Egg Nebula to create the grains recovered from the meteorite, which landed in Australia.
Photos: Wonders of the universe
Show Caption
53 of 56
The former North Star, Alpha Draconis or Thuban, is circled here in an image of the northern sky.
Photos: Wonders of the universe
Show Caption
54 of 56
Galaxy UGC 2885, nicknamed the "Godzilla galaxy," may be the largest one in the local universe.
Photos: Wonders of the universe
Show Caption
55 of 56
The host galaxy of a newly traced repeating fast radio burst acquired with the 8-meter Gemini-North telescope.
Photos: Wonders of the universe
Show Caption
56 of 56
Meet the fastest asteroid in our solar system, which zips around the sun every 113 days. This artist's rendering shows the asteroid 2021 PH27 (top right) and Mercury (below) orbiting the sun.
Photos: Wonders of the universe
Show Caption
1 of 56
A ghostly set of  X-ray rings were found around a black hole with a companion star. These rings are created by light echoes.
Photos: Wonders of the universe
Show Caption
2 of 56
This image, taken with the Atacama Large Millimeter/submillimeter Array in Chile, shows the PDS 70 system 400 light-years away. This planetary system is still forming and still in the process of being formed. One of the planets in the system has a moon-forming disk around it.
Photos: Wonders of the universe
Show Caption
3 of 56
This image shows supernova 2018zd (pictured as the large white dot on the right), a new type of supernova called an electron capture. To the left is the galaxy NGC 2146.
Photos: Wonders of the universe
Show Caption
4 of 56
This image from the STARFORGE simulation shows the "Anvil of Creation," a giant gas cloud with individual stars forming inside of it.
Photos: Wonders of the universe
Show Caption
5 of 56
Astronomers used NASA's Chandra X-ray Observatory to study the supernova remnant Cassiopeia A and discovered titanium, shown in light blue, blasting out of it. The colors represent other elements detected, like iron (orange), oxygen (purple), silicon (red) and magnesium (green).
Photos: Wonders of the universe
Show Caption
6 of 56
The supermassive black hole at the center of the M87 galaxy, the first to ever be imaged, can now be seen in polarized light. Swirling lines reveal the magnetic field near the edge of the black hole.
Photos: Wonders of the universe
Show Caption
7 of 56
This image from the Sloan Digital Sky Survey shows the galaxy J0437+2456, which includes a supermassive black hole at its center that appears to be moving.
Photos: Wonders of the universe
Show Caption
8 of 56
This artist's impression shows how the distant quasar P172+18 and its radio jets may have looked 13 billion years ago. The light from the quasar has taken that long to reach us, so astronomers observed the quasar as it looked in the early universe.
Photos: Wonders of the universe
Show Caption
9 of 56
This image shows the vicinity of the Tucana II ultrafaint dwarf galaxy, captured by the SkyMapper telescope.
Photos: Wonders of the universe
Show Caption
10 of 56
These images show two giant radio galaxies found with using the MeerKAT telescope. The red in both images shows the radio light being emitted by the galaxies against a background of the sky as it is seen in visible light.
Photos: Wonders of the universe
Show Caption
11 of 56
This artist's conception of quasar J0313-1806 depicts it as it was 670 million years after the Big Bang. Quasars are highly energetic objects at the centers of galaxies, powered by black holes and brighter than entire galaxies.
Photos: Wonders of the universe
Show Caption
12 of 56
Shown here is a phenomenon known as zodiacal light, which is caused by sunlight reflecting off tiny dust particles in the inner solar system.
Photos: Wonders of the universe
Show Caption
13 of 56
This artist's impression of the distant galaxy ID2299 shows some of its gas being ejected by a "tidal tail" as a result of a merger between two galaxies.
Photos: Wonders of the universe
Show Caption
14 of 56
This diagram shows the two most important companion galaxies to the Milky Way: the Large Magellanic Cloud (left) and the Small Magellanic Cloud. It was made using data from the European Space Agency Gaia satellite.
Photos: Wonders of the universe
Show Caption
15 of 56
The Blue Ring Nebula is thought to be a never-before-seen phase that occurs after the merger of two stars. Debris flowing out from the merger was sliced by a disk around one of the stars, creating two cones of material glowing in ultraviolet light.
Photos: Wonders of the universe
Show Caption
16 of 56
The red supergiant star Betelgeuse, in the constellation of Orion, experienced unprecedented dimming late in 2019. This image was taken in January using the European Southern Observatory's Very Large Telescope.
Photos: Wonders of the universe
Show Caption
17 of 56
This is an infrared image of Apep, a Wolf-Rayet star binary system located 8,000 light-years from Earth.
Photos: Wonders of the universe
Show Caption
18 of 56
An artist's illustration, left, helps visualize the details of an unusual star system, GW Orionis, in the Orion constellation. The system's circumstellar disk is broken, resulting in misaligned rings around its three stars.
Photos: Wonders of the universe
Show Caption
19 of 56
This is a simulation of two spiral black holes that merge and emit gravitational waves.
Photos: Wonders of the universe
Show Caption
20 of 56
This artist's illustration shows the unexpected dimming of the star Betelgeuse.
Photos: Wonders of the universe
Show Caption
21 of 56
This extremely distant galaxy, which looks similar to our own Milky Way, appears like a ring of light.
Photos: Wonders of the universe
Show Caption
22 of 56
This artist's interpretation shows the calcium-rich supernova 2019ehk. The orange represents the calcium-rich material created in the explosion. Purple reveals gas shed by the star right before the explosion.
Photos: Wonders of the universe
Show Caption
23 of 56
The blue dot at the center of this image marks the approximate location of a supernova event which occurred 140 million light-years from Earth, where a white dwarf exploded and created an ultraviolet flash. It was located close to tail of the Draco constellation.
Photos: Wonders of the universe
Show Caption
24 of 56
This radar image captured by NASA's Magellan mission to Venus in 1991 shows a corona, a large circular structure 120 miles in diameter, named Aine Corona.
Photos: Wonders of the universe
Show Caption
25 of 56
When a star's mass is ejected during a supernova, it expands quickly. Eventually, it will slow and form a hot bubble of glowing gas. A white dwarf will emerge from this gas bubble and move across the galaxy.
Photos: Wonders of the universe
Show Caption
26 of 56
The afterglow of short gamma ray burst that was detected 10 billion light-years away is shown here in a circle. This image was taken by the Gemini-North telescope.
Photos: Wonders of the universe
Show Caption
27 of 56
This Hubble Space Telescope image shows NGC 7513, a barred spiral galaxy 60 million light-years away. Due to the expansion of the universe, the galaxy appears to be moving away from the Milky Way at an accelerate rate.
Photos: Wonders of the universe
Show Caption
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(CNN)A newly discovered asteroid is sticking close to our sun -- much closer than our own planet Earth.

The asteroid, called 2021 PH27, completes an orbit around the sun every 113 days and comes within 12.4 million miles (20 million kilometers) of our star.

That gives this space rock the distinction of having the shortest known orbital period for an asteroid -- and only the second shortest orbit around the sun after Mercury, which takes 88 days to complete its orbital journey around our star.
Scott Sheppard, an astronomer at the Carnegie Institution for Science, discovered the asteroid in twilight observations made by Brown University astronomers Ian Dell'Antonio and Shenming Fu on August 13. Dell'Antonio, a professor of physics, and Fu, a doctoral student, took the images using the Dark Energy Camera mounted on the Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory in Chile.
Multiple aspects of the asteroid surprised Sheppard.
The asteroid is 0.6 miles (1 kilometer) in size and "very few asteroids this size in the inner solar system likely exist that are unknown," he said.

"2021 PH27 gets so close to the Sun that its surface can reach temperatures of 900 degrees Fahrenheit (482 degrees Celsius), hot enough to melt lead," said Sheppard via email. "Because of these extreme temperatures, it is unlikely 2021 PH27 is composed of any volatile material, and it is most likely made up of rock with maybe some metal like iron."
It has an unstable orbit that crosses the orbits of Mercury and Venus as they make their way around the sun. Within a few million years, the asteroid's orbit will likely cause its doom. The rocky fragment could collide with Mercury or Venus, or the sun itself, or be knocked out of its current position in the solar system.
This diagram shows the orbits of the newly discovered asteroid (orange) as well as Earth (blue), Mercury (white) and Venus (yellow) around the sun.
This diagram shows the orbits of the newly discovered asteroid (orange) as well as Earth (blue), Mercury (white) and Venus (yellow) around the sun.
The asteroid is so near the sun's massive gravitational field of the sun that it experiences effects on its orbit, Sheppard said.
Why asteroid Phaethon acts like a comet as it nears the sun
Why asteroid Phaethon acts like a comet as it nears the sun
The newfound asteroid is only one of about 20 Atira asteroids, which are those asteroids that are completely interior to Earth's orbit of the sun.

While there are a few known asteroids that come nearly as close to the sun as 2021 PH27, they have much longer orbits.
"Some of these asteroids have been seen to have dust in their orbits, suggesting the asteroids are slowly fragmenting or cracking apart from the extreme thermal stresses on these objects," Sheppard said.
One notable example of this is Phaethon, the cometlike asteroid that creates the Geminid meteor showers that occur in our skies every December.
Tracking down an asteroid
But where did this space rock come from? That's one of the questions Sheppard wants to investigate next, but he has some ideas based on the preliminary observations.
It's likely that the asteroid became dislodged from the main asteroid belt located between Mars and Jupiter, but Sheppard hasn't ruled out the possibility that 2021 PH27 is actually an extinct comet.
"It could be an extinct comet as comets are known to come from the outer Solar System on elongated, long period orbits and gravitationally interact with the inner planets to get more circular shorter period orbits that keep them in the inner solar system for long periods of time," Sheppard explained. The inner planets include Mercury, Venus, Earth and Mars.
When this happens, some of the comet's elements will evaporate until it no longer looks like a comet. Instead, it's just the leftover remnants.
New space telescope could spot potentially hazardous asteroids heading for Earth
New space telescope could spot potentially hazardous asteroids heading for Earth
Sheppard typically searches for incredibly distant objects in the solar system and beyond. However, it's also crucial to understand the population of asteroids close to Earth's orbit. Near-Earth asteroids have a chance of impacting Earth in the future, but some of them are incredibly difficult to observe because they approach our planet during the daytime.
"The space interior to Earth's orbit has been relatively unexplored to date," Sheppard said. "It is hard to observe the region towards the Sun because of the Sun's extreme glare."
But the Dark Energy Camera has a large field of view, making it a powerful tool to search for otherwise elusive objects like 2021 PH27 -- especially during the twilight hours as the sun sets and just before it rises.
After Sheppard's discovery, astronomer David Tholen at the University of Hawai'i measured the asteroid's position and predicted where it could be observed the next night. This enabled multiple telescopes to observe the asteroid from Chile and South Africa on August 14 and 15. These astronomers postponed observations for their own research to assist with learning more about the asteroid.
"Although telescope time is very precious, the international nature and love of the unknown makes astronomers very willing to override their own science and observations to follow up new interesting discoveries like this," Sheppard said. "We are so grateful for all of our collaborators who enabled us to act quickly on this discovery."
Soon, the asteroid will pass behind the sun and won't be observable until early 2022. Sheppard is eager to learn more about the asteroid's composition and its origin.
"Where are these inner asteroids coming from? Some are recently dislodged Main Belt Asteroids, other might be extinct comets, but there could be another source population, such as the Vulcanoids, which are a hypothetical population of asteroids," Sheppard said.