When I first start­ed study­ing Astron­o­my, my book brought me up the state of knowl­edge about 1940.  How­ev­er, I also was very aware of the space pro­gram that was rewrit­ing those books. Mars was dis­cov­ered to have craters. Venus was an oven the melt­ed lead. And, astro­nauts walked on the Moon.

We always had sus­pi­cion of plan­ets orbit­ing oth­er stars, but we were left to sci­ence fic­tion to image those. Now through advanced optics and big new obser­va­to­ries, extra­so­lar plan­ets have become a real­i­ty of sci­ence. Some have been imaged, but now we have a video of plan­ets cir­cling anoth­er star:

Video of plan­ets cir­cling anoth­er star

By study­ing mete­orites, we can esti­mate the con­stituent parts of Ter­res­tri­al plan­ets. In Paul Voosen’s arti­cle from Sci­ence Week­ly, we find that water and oth­er volatiles are present.  Since mete­orites are the build­ing blocks of plan­ets, it sug­gests that Earth like plan­ets can form around oth­er stars.

Here is anoth­er exam­ple of a close orbit­ing ‘Earth like’ exo­plan­et in a video from Dr. Becky Smethurst.

Dust grains are the for­ma­tion of plan­ets.  Here is an effort to under­stand those grains:

https://www.sciencedaily.com/releases/2023/01/230113145324.htm