Oct 23, 2026 · 19 min · 11 segments
A stellar explosion from more than 12.5 billion years ago. A comet discovered accidentally by a telescope built to study dark matter. And a white dwarf whose unusual chemistry makes it appear green…
Our first story takes us more than 12 billion years into the past.
Astronomers using the James Webb Space Telescope have discovered a brilliant transient object called AT2026abck.
The current evidence suggests that it may be an extremely distant supernova, an exploding star.
But researchers are still studying exactly what type of explosion it was, so this is one of those stories where the word may matters.
The event happened when the universe was only about 1.15 billion years old.
Its light has traveled for more than 12.5 billion years before reaching Webb.
And astronomers seem to have caught the explosion extremely early.
Perhaps only 4 to 10 days after it began, measured in the star's own time.
That is extraordinary because distant supernovae are usually discovered after much more of the event has already unfolded.
But here is where time becomes really strange.
Because the universe has expanded while the light was traveling toward us, the event appears to unfold much more slowly from Earth.
A few days in the supernova's own frame can become several times longer in hours.
This is called cosmological time dilation.
It is not the star slowing down.
It is not our clocks speeding up.
It is a consequence of space itself expanding while the light crosses the universe.
So Webb is not simply looking far away.
It is watching an ancient explosion through a clock stretched by the expansion of the cosmos.
Our second story goes even farther back.
Not to the first stars.
Not to the first galaxies.
Of course, no telescope can photograph those five minutes directly.
The early universe was far too hot and dense for light to travel freely in the way it does today.
But it left evidence behind.
Our first story takes us more than 12 billion years into the past.
Astronomers using the James Webb Space Telescope have discovered a brilliant transient object called AT2026abck.
The current evidence suggests that it may be an extremely distant supernova, an exploding star.
But researchers are still studying exactly what type of explosion it was, so this is one of those stories where the word may matters.
The event happened when the universe was only about 1.15 billion years old.
Its light has traveled for more than 12.5 billion years before reaching Webb.
And astronomers seem to have caught the explosion extremely early.
Perhaps only 4 to 10 days after it began, measured in the star's own time.
That is extraordinary because distant supernovae are usually discovered after much more of the event has already unfolded.
But here is where time becomes really strange.
Because the universe has expanded while the light was traveling toward us, the event appears to unfold much more slowly from Earth.
A few days in the supernova's own frame can become several times longer in hours.
This is called cosmological time dilation.
It is not the star slowing down.
It is not our clocks speeding up.
It is a consequence of space itself expanding while the light crosses the universe.
So Webb is not simply looking far away.
It is watching an ancient explosion through a clock stretched by the expansion of the cosmos.
Our second story goes even farther back.
Not to the first stars.
Not to the first galaxies.
Of course, no telescope can photograph those five minutes directly.
The early universe was far too hot and dense for light to travel freely in the way it does today.
But it left evidence behind.
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