Our Birth in the Local Bubble

The <a href="https://webbtelescope.org/images" rel="noopener ugc nofollow" target="_blank">latest Webb telescope images</a> of 19 face-on spiral galaxies are stunning. They show dust lanes with dark holes or bubbles and lots of stars sprinkled all over. If we were to look at the Milky-Way disk from above, it would likely appear the same. The evidence that we live in a punctured interstellar medium is evident around us. In particular, the Sun just entered such a hole, called the <a href="https://www.nature.com/articles/s41586-021-04286-5" rel="noopener ugc nofollow" target="_blank">Local Bubble</a>, over the past few million years. This Bubble is a cavity of rarefied hot gas surrounded by a dense shell of cold gas and dust with a radius of a few hundred light years. Most of the young stars near the Sun lie on the expanding shell of this Bubble. The latest <a href="https://www.nature.com/articles/s41586-021-04286-5" rel="noopener ugc nofollow" target="_blank">data</a> indicates that a burst of supernova explosions near the bubble center triggered its expansion about 14 million years ago. <a href="https://avi-loeb.medium.com/our-birth-in-the-local-bubble-fe2806e36a6b">Website</a>