Space & astronomy · the experiment
Listen to the comet before its end
A comet that grazes the Sun, three days at a radio telescope, an outburst on the eve of its break-up. Four questions, from beginner to expert.
1 · Recall the discovery
Beginner
What did the team detect, for the first time, in a Kreutz sungrazing comet?
2 · Add the dust
The gas lost during the 3 April outburst amounts to 0.4% of the comet's mass. The team assumes that the dust dragged along weighs twice as much as that gas.
Intermediate
What share of its mass did the comet then lose in total?
3 · Predict the rise without an outburst
Outside outbursts, the HCN output follows the usual rule for comets: it grows as the inverse square of the distance to the Sun (fit: exponent −1.97 ± 0.14).
Expert
On average the comet was about 0.23 astronomical units from the Sun on 1 April and about 0.11 on 3 April. By about how much should its output be multiplied?
4 · Draw the lesson from HCN
Other work makes C/2026 A1 a second-generation fragment of Aristotle's comet (372 BC), and a fragment of the comet of AD 363: it would already have crossed twice the zone where the Sun's gravity can tear it apart.
Expert
If so, what does the HCN detection show?
Comet heard
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