XJ1500+0154
Credit: X-ray: NASA/CXC/UNH/D.Lin et al, Optical: CFHT,
Illustration: NASA/CXC/M.Weiss
A trio of X-ray observatories has captured a remarkable event in their data: a decade-long binge by a black hole almost two billion light years away. This discovery was made using data from NASA's Chandra X-ray Observatory, Swift Observatory, and ESA's XMM-Newton, as reported in our press release.
This artist's illustration depicts what astronomers call a "tidal
disruption event," or TDE. This is when an object, such as a star,
wanders too close to a black hole and is destroyed by tidal forces
generated from the black hole's intense gravitational forces. During a
TDE, some of the stellar debris is flung outward at high speeds, while
the rest (shown as the red material in the illustration) becomes hotter
as it falls toward the black hole, generating a distinct X-ray flare. A wind blowing away from this infalling material is shown in blue.
Among observed TDEs, this event involved either the most massive star
to be completely ripped apart and devoured by a black hole or the first
instance where a smaller star was completely ripped apart. The
resulting X-ray source is known as XJ1500+154 and is located in a small
galaxy about 1.8 billion light years from Earth. The optical image in
the left inset shows this galaxy and a cross to mark the location of
XJ1500+0154. This image reveals that XJ1500+0154 is found in the center
of the galaxy, implying that the source likely originates from a
supermassive black hole that resides there. The image on the right shows
XJ1500+0154 in the Chandra image covering the same field.
The source was not detected in a Chandra observation on April 2, 2005, but was detected in an XMM-Newton
observation on July 23, 2005, and reached peak brightness in a Chandra
observation on June 5, 2008. These observations show that the source
became at least 100 times brighter in X-rays. Since then, Chandra,
Swift, and XMM-Newton have observed it multiple times.
The X-ray data also indicate that radiation from material surrounding this black hole has consistently surpassed the so-called Eddington limit,
defined by a balance between the outward pressure of radiation from the
hot gas and the inward pull of the gravity of the black hole.
This TDE may help answer the question as to how supermassive black holes
in the early universe grow. If supermassive black holes can grow, from
TDEs or other means, at rates above those corresponding to the Eddington
limit, this could explain how supermassive black holes were able to
reach masses about a billion times higher than the sun when the universe
was only about a billion years old.
A paper describing these results appears in the February 6th issue of
Nature Astronomy. The authors are Dacheng Lin (University of New
Hampshire), James Guillochon (Harvard-Smithsonian Center for
Astrophysics), Stefanie Komossa (QianNan Normal University for
Nationalities), Enrico Ramirez-Ruiz (University of California, Santa
Cruz), Jimmy Irwin (University of Alabama), Peter Maksym
(Harvard-Smithsonian), Dirk Grupe (Morehead State University), Olivier
Godet (CNRS), Natalie Webb (CNRS), Didier Barret (CNRS), Ashley Zauderer
(New York University), Pierre-Alain Duc (CEA-Saclay), Eleazar Carrasco
(Gemini Observatory), and Stephen Gwyn (Herzberg Institute of
Astrophysics).
NASA's Marshall Space Flight Center in Huntsville, Alabama, manages
the Chandra program for NASA's Science Mission Directorate in
Washington. The Smithsonian Astrophysical Observatory in Cambridge,
Massachusetts, controls Chandra's science and flight operations.
Fast Facts for XJ1500+0154:
Scale: Inset images are 11 arcsec across (about about 92,000 light years)
Category: Quasars & Active Galaxies
Coordinates (J2000): RA 15h 00m 52.10s | Dec Dec: +01 54 53.00
Constellation: Virgo
Observation Date: 23 Feb 2015
Observation Time: 10 hours
Obs. ID: 6601
Instrument: ACIS
References: Lin, D. et al, 2017, Nature Astronomy (accepted)
Color Code: X-ray (Pink); Optical (Red, Green, Blue)
Distance Estimate: About 1.8 billion light years
Source: NASA’s Chandra X-ray Observatory
