Supernova explosions occur when massive stars run out of nuclear fuel, collapse and explode in titanic blasts visible across the cosmos. They also can be triggered when a white dwarf in a binary star system siphons off enough mass from a companion to ignite runaway nuclear fusion in its core to begin the supernova process. Both types of supernovae have been spotted in a galaxy known as NGC 5468, a spectacular face-on spiral whose orientation makes it easier to spot such exploding stars. Over the past two decades, NGC 5468, located some 130 million light years from Earth in the constellation Virgo, has hosted at least five supernovae: SN 1999cp, SN 2002cr, SN2002ed, SN2005P, and SN2018dfg.
Related Articles
Dark matter even darker than once thought
Astronomers using observations from the NASA/ESA Hubble Space Telescope and NASA’s Chandra X-ray Observatory have studied how dark matter in clusters of galaxies behaves when the clusters collide. The results show that dark matter interacts with itself even less than previously thought, and narrows down the options for what this mysterious substance might be.
Exiled exoplanet kicked out of star’s local neighbourhood?
A planet discovered last year sitting at an unusually large distance from its star — 16 times farther than Pluto is from the Sun — may have been kicked out of its birthplace close to the star in a process similar to what may have happened early in our own solar system’s history. The planet’s 13-million-year-old parent star is known as HD 106906 and lies 300 light-years away.