From the September 2014 issue

A recent study found that a type Ia supernova’s original star could be anywhere from 0.9 to 1.4 times our Sun’s mass. Astronomers use these blasts’ brightnesses to estimate distances, so are those measurements now incorrect?

Richard Cole, Ann Arbor, Michigan
By | Published: September 29, 2014 | Last updated on May 18, 2023

All supernovae blasts have similar shapes to their light profiles, and to compare them, astronomers standardize their peak brightnesses.

Not at all! All of astronomers’ careful work to measure type Ia supernova distances still holds up, and the 2011 Nobel laureates in physics get to keep their prizes for using these stellar explosions to find that the universe’s expansion is accelerating. In fact, we now have enough evidence from other methods to show this speed-up even without type Ia supernovae.

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