Peter Michaud
Science Highlights
Data from the Gemini Multi-Object Spectrograph on Gemini
South verifies one of the most distant superluminous supernovae
ever studied. Astronomers at Gemini South confirm a new class of
variable stars, called Blue Large-Amplitude Pulsators. Joint Gemini
and Canada-France-Hawai‘i GRACES observations at Maunakea
help in the study of a white dwarf star hurtling through our Galactic
neighborhood 50 million years after a supernova blast. And Gemini
near-infrared data from Gemini North unmask the mysterious
Infrared Quintuplet at the Galactic center.
A Super-distant, Superluminous Supernova
Observations conducted with the Gemini Multi-Object Spectrograph on the 8-meter Gemini
South telescope have confirmed that a brilliant explosion more than three times as bright as
our Milky Way Galaxy is one of the most distant supernovae ever studied. The event, known
as DES15E2mlf, occurred about 3.5 billion years after the Big Bang, at a period known as
“cosmic high noon,” when the rate of star formation in the Universe had reached its peak.
DES15E2mlf was initially detected in November 2015 by the Dark Energy Survey (DES). Fol-
low-up observations at Gemini South not only confirmed the object’s distance of 10 billion
light years, but also revealed its unusual nature. Previous observations of superluminous
supernovae show that they typically reside in low-mass or dwarf galaxies, which tend to be
less enriched in metals than more massive galaxies. However, University of California Santa
Cruz astronomers Yen-Chen Pan and Ryan Foley, who led the Gemini investigation as part
of an international team of DES collaborators, found that the host galaxy of DES15E2mlf, is a
fairly massive normal-looking galaxy, which goes counter to current thinking.
October 2017
GeminiFocus
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