Chapters 21-25 Summary

Ekstrom introduces Rachel to Michael Tolland, a well-known oceanographer with a highly-popular weekly television show, and Corky Marlinson, a world-renowned astrophysicist. Preparations are being made for President Herney's press conference announcing the discovery. Corky gives Rachel a lesson in meteorites, explaining what differentiates meteorites from rocks on earth. The first distinguishing feature is the outer fusion crust of the rock, which gets charred from contact with earth's atmosphere and gravitational pull. This also causes directional striations in the crust. The second feature is the presence of chondrules, small metallic blobs within the rock that are only found in rocks from space. The third feature is the nickel content, which is mid-range, while rocks on earth have either low or high nickel content.

Corky then shows Rachel a core sample from the meteorite found in the Milne Ice Shelf. Rachel can see...