Two Worlds Collided

Earlier this week, team leaders from different parts of the world collaborated to photograph a special and rare cosmic event. Though scientists Seppo Mattila and Miguel Pérez-Torres once led separate, distant lives, they both study stellar evolution, the death and decay of stars. However, since 2005, they have combined efforts to capture the first photographs of a star’s battle with a supermassive black hole (SMBH). Mattila and Pérez-Torres found that it does not end well for the star in question; the result is a tidal disruption event (TDE). A TDE, like the one photographed by Mattila and Pérez-Torres, occurs after an unlucky star skirts the edge of the event horizon of a black hole.  Pieces of the star’s gaseous layers are slowly stripped away, and the material not absorbed into the black hole is spewed out in a jet stream of stardust.

Artist's rendition of a tidal disruption event (TDE).
Sophia Dagnello, NRAO/AUI/NSF; NASA, STScI

Who wins in a battle with a black hole? Well, what we know is that anything we have ever observed, including light, will have everything to lose if it gets too close to a black hole. Because of a black hole’s incredible mass, ability to emit intense amounts of radiation, and an overwhelming force of gravity, it always wins. The SMBH in question sits comfortably on its throne in NGC 6390, one of the two galaxies currently merging in Arp 299, a galaxy sitting an astonishing 130,000,000 light years away.

  Arp 299: Black Holes in Colliding Galaxies   NASA ,  JPL-Caltech ,  GSFC ,  Hubble ,  NuSTAR

Arp 299: Black Holes in Colliding Galaxies

Mattila was familiar with Arp 299 long before the TDE discovery. In hopes of finding supernovae in Arp 299, Mattila conducted research on the galaxy pair at the University of Turku in Finland. In 2005, Mattila published a peculiar finding -  a strong event emitting infrared light from within Arp 299. Mattila noted that the signal created by this mysterious event was not emitting radiation in the x-ray and visual wavelengths, which would be expected from a supernova explosion. Instead of finding a supernova explosion, it was apparent Matilla had stumbled upon something else.

Pérez-Torres of the Instituto de Astrofísica de Andalucía in Spain was coincidentally studying Arp 299, but for an entirely unrelated supernovae study. Pérez-Torres noticed a radio wave signal from the same mysterious event and was curious to uncover more about its origin.  He discovered Mattila’s publication on Arp 299, and the scientists decided to join forces to determine what the event could be. After a decade, a team of more than 30 scientists, led by Mattila and Pérez-Torres, captured images of a jet stream of stardust caused by a TDE. The stunning jet stream is the unfortunate demise of a star getting too close to a SMBH.

The observation of a TDE is much rarer than a supernova event - up to 1000 times as rare! The creation of jet streams from star interactions with SMBHs was modeled on computers, but capturing high quality photos of the event happening was unheard of. Being near enough to observe a TDE has left the team of scientists with an admirable and valuable product of research. “We should feel very lucky that nature actually provided us such an event to witness,” said Mattila. With this new observation, scientists have a greater understanding into the behaviors of black holes and the mysteries of a larger Universe.

If you're really feeling nerdy and curious, here is the paper written by Seppo Mattila and Miguel Pérez-Torres.