(CNN) —
An unusual object detected streaking across the sky last month was a comet that originated outside our solar system, observations have confirmed, becoming only the second observed interstellar object to cross into our solar system.
It has been named 2I/Borisov by the International Astronomical Union’s Minor Planet Center. And it’s anywhere between 1.2 and 10 miles in diameter, Karen Meech and her colleagues at the University of Hawaii say.
Observations by NASA’s Jet Propulsion Laboratory Solar System Dynamics Group have supported that this comet has the most hyperbolic orbit out of the thousands of known comets.

Photos: Wonders of the universe
PHOTO:
European Southern Observatory
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
PHOTO:
Sloan Digital Sky Survey
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
PHOTO:
M. Kornmesser/European Southern Observatory
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
PHOTO:
Anirudh Chiti/MIT
This image shows the vicinity of the Tucana II ultrafaint dwarf galaxy, captured by the SkyMapper telescope.

Photos: Wonders of the universe
PHOTO:
I. Heywood/Oxford/Rhodes/SARAO
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
PHOTO:
NOIRLab/NSF/AURA/J. da Silva
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
PHOTO:
Zolt Levay/Space Telescope Science Institute
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
PHOTO:
M. Kornmesser/ESO
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
PHOTO:
Laurent Chemin/ESA/Gaia/DPAC
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
PHOTO:
NASA/JPL-Caltech/M. Seibert/K. Hoadley/GALEX Team
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
PHOTO:
ESO/M. Montargès et al.
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
PHOTO:
European Southern Observatory
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
PHOTO:
ESO/L. Calçada, Exeter/Kraus et al.
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
PHOTO:
N. Fischer, H. Pfeiffer, A. Buonanno, MPIGP, SXS Collaboration
This is a simulation of two spiral black holes that merge and emit gravitational waves.

Photos: Wonders of the universe
PHOTO:
ESO, ESA/Hubble, M. Kornmesser
This artist's illustration shows the unexpected dimming of the star Betelgeuse.

Photos: Wonders of the universe
PHOTO:
Rizzo et al./ALMA/European Southern Observatory
This extremely distant galaxy, which looks similar to our own Milky Way, appears like a ring of light.

Photos: Wonders of the universe
PHOTO:
Aaron M. Geller, Northwestern University
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
PHOTO:
Northwestern University
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
PHOTO:
From NASA/JPL
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
PHOTO:
Mark Garlick/University of Warwick
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.