Probably they are looking for the word "atmosphere". But personally, I hate when reporting uses mph for orbital velocity. It's supposed to be more relatable to

Probably they are looking for the word "atmosphere". But personally, I hate when reporting uses mph for orbital velocity. It's supposed to be more relatable to non-experts or space buffs. (boffins if you prefer) It isn't though, because nobody has experience with thousands of mph. Big numbers are opaque. So even for the ignorant, miles (or km) per second is more meaningful, and of course for people who are interested in space, they have a rough idea of how fast things in orbit or meteors go.