A trail of starlight thought to possibly indicate a runaway supermassive black hole may be something much more mundane: a spiral galaxy seen edge on, a new study finds.
In February, astronomer Pieter van Dokkum of Yale University and colleagues reported spotting a line of stars near a compact galaxy in Hubble Space Telescope images. The researchers’ analysis suggested that three galaxies had interacted and merged, kicking a supermassive black hole out of its host galaxy. The black hole then traveled through a nearby gas cloud, the scenario goes, triggering the formation of stars in a line that points toward the home galaxy and revealing the black hole’s madcap escape.
But other researchers have been skeptical of this interpretation, with some suggesting that the scenario is too complex to explain the linear feature. In the new study, “we decided to explore what we thought was the most simple explanation,” says astronomer Ignacio Trujillo of the Instituto de Astrofísica de Canarias in Tenerife, Spain.
So he and his colleagues compared characteristics of the linear feature with those of a well-studied spiral galaxy called IC 5249, which astronomers know we see edge on from Earth. The team looked at the objects’ masses, surface brightnesses and general motions of stars. The properties of the galaxy and linear feature matched closely, the researchers report in the study.
The debate’s resolution may have to wait at least until this summer when better imagery from Hubble arrives.
Galaxy IC 5249 (circled) is a spiral galaxy viewed edge on from Earth. That galaxy looks similar to a trail of light previously suggested to be stars that formed in the wake of a runaway black hole, casting doubt on the black hole’s existence, researchers say.
DSS2/STSCI, UK SCHMIDT TELESCOPE/AAO
PS: I have run short of disk space for images... It would have been a lot easier to manage on this site rather than uploading to a different site.
In February, astronomer Pieter van Dokkum of Yale University and colleagues reported spotting a line of stars near a compact galaxy in Hubble Space Telescope images. The researchers’ analysis suggested that three galaxies had interacted and merged, kicking a supermassive black hole out of its host galaxy. The black hole then traveled through a nearby gas cloud, the scenario goes, triggering the formation of stars in a line that points toward the home galaxy and revealing the black hole’s madcap escape.
But other researchers have been skeptical of this interpretation, with some suggesting that the scenario is too complex to explain the linear feature. In the new study, “we decided to explore what we thought was the most simple explanation,” says astronomer Ignacio Trujillo of the Instituto de Astrofísica de Canarias in Tenerife, Spain.
So he and his colleagues compared characteristics of the linear feature with those of a well-studied spiral galaxy called IC 5249, which astronomers know we see edge on from Earth. The team looked at the objects’ masses, surface brightnesses and general motions of stars. The properties of the galaxy and linear feature matched closely, the researchers report in the study.
The debate’s resolution may have to wait at least until this summer when better imagery from Hubble arrives.
Galaxy IC 5249 (circled) is a spiral galaxy viewed edge on from Earth. That galaxy looks similar to a trail of light previously suggested to be stars that formed in the wake of a runaway black hole, casting doubt on the black hole’s existence, researchers say.
DSS2/STSCI, UK SCHMIDT TELESCOPE/AAO
PS: I have run short of disk space for images... It would have been a lot easier to manage on this site rather than uploading to a different site.
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