Chandra's galactic-center object is still a lesson in the word possible, and the paper's June 16 brief on a possible supernova remnant near the galactic core was right to make the important word "if."

NASA says astronomers may have found a supernova remnant in Sagittarius C using Chandra X-ray Observatory data, with the evidence centered on an X-ray blob about 26,000 light-years from Earth, supported by Chandra and XMM-Newton data and radio context from MeerKAT [1].

Chandra's own photo page keeps the conditional frame by saying the object would be expanding at about two million miles per hour and would be at least about 1,700 years old, if it is indeed a remnant [2].

The caution is not decorative, because NASA says the team did not see enhanced key elements in the remnant, possibly because debris has mixed with surrounding gas, and it names an alternate explanation in which the hot gas comes from massive stars in the region, though the authors think that is unlikely because the blob's X-ray emission is more than ten times brighter than known stellar clusters [1][2].

The social version wants a cleaner sentence, cosmic explosion near the monster black hole, but that may be where the evidence ends rather than where it starts, and science is often most interesting before certainty arrives.

-- KENJI NAKAMURA, Tokyo