A new star appears in Ophiuchus

Tycho Brahe saw a brilliant new object in Cassiopeia; it was later identified as the supernova SN 1572.

The bright star-like object stood in a familiar constellation, challenging beliefs that the distant heavens never changed.

Tycho's subsequent careful measurements tracked the object's position and brightness; the first sighting was on this date.

The appearance of SN 1572 opened new arguments about celestial change; its physical interpretation came centuries later.

Johannes Kepler observed the bright new star of 1604 in the constellation Ophiuchus.

Observers could see this extraordinary object without a telescope; the remnant remains a subject of study.

The 1604 outburst furnished another striking challenge to the doctrine of immutable heavens.

He recorded three small points near Jupiter, initially regarding them as background stars.

The positions of the lights were unusual enough to prompt repeated observations on later nights.

His first dated observations began the sequence that established satellites orbiting Jupiter.