Rapid Expansion of Supernova Remnants

As we know, secular cosmologists use the assumption that the universe is 4.5 billion years old as a starting point. This provides the framework for other theories and models. Those of us involved with biblical creation science see that they are constantly surprised when their expectations fail and observed evidence supports a young cosmos (such as this example) — and by default, a young Earth. A supernova (-novae or -novas, plural) is a star that exploded. The remnants expand, but have perplexed secular scientists.

A star explodes and leaves remnants, such as this veil nebula. Scientists have problems when supernovas of known age are calculated to be far older than what is known.
Veil nebula, a supernova remnant, NASA/ESA/Hubble Heritage Team (usage does not imply endorsement of site contents)
Although the process is uncertain, astronomers calculate the age of the explosion by the expansion of the remnants. Problems have arisen when supernovas that have been observed are calculated to have happened much too long ago in the cosmic evolution scheme. Explanations for the disparities are unconvincing and even raise additional questions. Creationists may get excited and use this information. However, since there are many uncertainties, we should use caution and not exceed what is known.
Our Milky Way has some 300 or more scattered supernova remnants that appear as beautiful nebulae. The Veil Nebula in Cygnus is well known. Astronomers have been puzzled by the paucity of predicted supernova remnants in the Milky Way: five times fewer than expected. Astrophysicist Paul Sutter tried to explain why at Universe Today on 6 Jan 2021. This year, Andrew Hopkins (The Conversation, 20 Jan 2023) reported more “possible” remnants found in the most detailed radio images—3 times as many in one segment—which may fill in the gaps.

The rest of the article is at "Supernova Remnants Expand Quickly."