ASASSN-15lh tagged posts

A New Light on Stellar Death

An artist's depiction of a rapidly spinning supermassive black hole surrounded the rotating leftovers of a star that was ripped apart by the tidal forces of the black hole. Credit: ESO, ESA/Hubble, M. Kornmesser

An artist’s depiction of a rapidly spinning supermassive black hole surrounded the rotating leftovers of a star that was ripped apart by the tidal forces of the black hole. Credit: ESO, ESA/Hubble, M. Kornmesser

Astronomers illuminate the role rapidly spinning black holes play in tidal disruption events. Back in 2015 when astronomers discovered an intense flare in a distant galaxy, they considered it the brightest supernova ever observed. Now, UC Santa Barbara astrophysicists and a group of international colleagues offer an entirely different interpretation based on new astronomical observation data from the Las Cumbres Observatory (LCO), a global robotic telescope network, and the Hubble Space Telescope.

The new information indicates that the event, called ASASSN-15lh, is actually a tidal...

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ASASSN’s creed – a surprising UV Rebrightening observed in a Superluminous Supernova

hypernovae

NASA’s artist impression of SN 2006gy, one of the most luminous hypernovae seen. Credit: NASA/CXC/M.Weiss

An international team has spotted a surprising UV rebrightening in a distant superluminous supernova, ASASSN-15lh. The event has baffled the scientists as has no hydrogen emission characteristic of superluminous supernovae and tidal disruption events. Also called hypernovae, these are dozens of times more luminous than normal supernovae. ASASSN-15lh, detected by the All Sky Automated Survey for SuperNovae (ASAS-SN) in 2015, is a real ‘assassin’ among these explosion events. It is about 200X more powerful than the average supernova and approximately 570 billion times brighter than our sun. It is so far the most luminous supernova ever detected.

Now, Brown et al have used data from NASA’...

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Magnetar could have Boosted Explosion of Extremely Bright Supernova

Artist impression of a magnetar boosting a super-luminous supernova and gamma-ray burst. Credit: Kavli IPMU

Artist impression of a magnetar boosting a super-luminous supernova and gamma-ray burst. Credit: Kavli IPMU

Calculations by scientists have found highly magnetized, rapidly spinning neutron stars called magnetars could explain the energy source behind 2 extremely unusual stellar explosions. Stellar explosions known as supernovae usually shine a billion times brighter than the Sun. Super-luminous supernovae (SLSNe) are a relatively new and rare class of stellar explosions, 10 – 100 times brighter than normal supernovae. But the energy source of their super-luminosity, and explosion mechanisms are a mystery and remain controversial amongst scientists.

A group of researchers tested a model that suggests that the energy to power the luminosity of two recently discovered SLSNe, SN 2011kl and AS...

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What is 10 miles across, but powers an explosion brighter than the Milky Way?

This is an artist's impression of the record-breakingly powerful, superluminous supernova ASASSN-15lh as it would appear from an exoplanet located about 10,000 light years away in the host galaxy of the supernova. Credit: Beijing Planetarium / Jin Ma

This is an artist’s impression of the record-breakingly powerful, superluminous supernova ASASSN-15lh as it would appear from an exoplanet located about 10,000 light years away in the host galaxy of the supernova. Credit: Beijing Planetarium / Jin Ma

Astronomers studying what may be the most powerful supernova ever seen, with energy of hundreds of billions of suns. At its heart is an object a little larger than 10 miles across that could be a very rare type of star called a magneta – but one so powerful that it pushes the energy limits allowed by physics. An international team of professional and amateur astronomers spotted the possible supernova, now called ASASSN-15lh, when it first flared to life in June 2015.

Krzysztof Stanek, turned to the movie This is Spinal Tap to find a way to des...

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