Space and Science

‘Dark twin’ of the Milky Way galaxy discovered

Ashley Strickland
By Ashley Strickland, CNN
4 minute read
Updated 9:54 AM EDT, Mon August 29, 2016
This illustration shows a massive star on the brink of explosion.
This illustration shows a massive star on the brink of explosion.
Chuck Carter/Caltech
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.
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.
CTIO/NOIRLab/NSF/AURA/J. da Silva
A ghostly set of X-ray rings were found around a black hole with a companion star. These rings are created by light echoes.
A ghostly set of X-ray rings were found around a black hole with a companion star. These rings are created by light echoes.
CXC/U.Wisc-Madison/S. Heinz et al./Pan-STARRS/NASA
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.
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.
ALMA/ESO/NAOJ/NRAO/Benisty et al.
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.
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.
NASA/STSCI/J. Depasquale; Las Cumbres Observatory
This image from the STARFORGE simulation shows the "Anvil of Creation," a giant gas cloud with individual stars forming inside of it.
This image from the STARFORGE simulation shows the "Anvil of Creation," a giant gas cloud with individual stars forming inside of it.
From Northwestern University/UT Austin
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).
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).
T. Sato et al./RIKEN/CXC/NASA
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.
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.
European Southern Observatory
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.
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.
Sloan Digital Sky Survey
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.
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.
M. Kornmesser/European Southern Observatory
This image shows the vicinity of the Tucana II ultrafaint dwarf galaxy, captured by the SkyMapper telescope.
This image shows the vicinity of the Tucana II ultrafaint dwarf galaxy, captured by the SkyMapper telescope.
Anirudh Chiti/MIT
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.
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.
I. Heywood/Oxford/Rhodes/SARAO
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.
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.
NOIRLab/NSF/AURA/J. da Silva