When the star that created this supernova remnant exploded in 1572, it was so bright that it was visible during the day. And though he wasn't the first or only person to observe this stellar spectacle, the Danish astronomer
Tycho Brahe wrote a book about his extensive observations of the event, gaining the honor of it being named after him.
Tycho's supernova remnant was created by the explosion of a white dwarf star, making it part of the so-called Type Ia class of supernovae used to track the expansion of the Universe. The expansion from the explosion is still continuing ~ 450 years later, as seen from Earth's vantage point roughly 10000 ly away.
Since much of the material being flung out from the shattered star has been heated by shock waves - similar to sonic booms from supersonic planes - passing through it, the remnant glows strongly in X-ray light.
For the first time, a movie has been made of the evolution of Tycho's supernova remnant. This sequence includes X-ray observations from
Chandra spaced out over a decade and a half.
The speed of the blast wave in the right and lower right directions is about twice as large as that in the left and the upper left directions. This range in speed of the blast wave's outward motion is caused by differences in the density of gas surrounding the supernova remnant. This causes an offset in position of the explosion site from the geometric center, determined by locating the center of the circular remnant. The size of the offset is ~ 10% of the remnant's current radius, towards the upper left of the geometric center. The maximum speed of the blast wave is ~ 12 million miles per hour.
The significant offset from the center of the explosion to the remnant's geometric center is a relatively recent phenomenon. For the first few hundred years of the remnant, the explosion's shock was so powerful that the density of gas it was running into did not affect its motion. The density discrepancy from the left side to the right has increased as the shock moved outwards, causing the offset in position between the explosion center and the geometric center to grow with time. So, if future X-ray astronomers, say 1000 years from now, do the same observation, they should find a much larger offset.