Dear Dr. Boli: My brother and I were talking about space stuff, and we were wondering: If we got into our limousine in Washington, D.C., and started driving now, how long would it take us to get to Mars? —Sincerely, Jeff Bezos.

Dear Sir: According to Google Maps, it would take 4 hours and 20 minutes to get from Kalorama in Washington to Mars, Pennsylvania, by the fastest route, under usual traffic conditions.

But since you mention space, Dr. Boli wonders whether you meant Mars the planet. Mars is some distance from the earth, and the roads are not kept in good repair. With Mars and the earth in their present positions, it would take you a very long time to get to Mars in your limousine. The best way to bring home the enormous distances involved is to say that you would have time to read À la recherche du temps perdu all the way through, and then read it again, before you got there. This assumes, of course, that your brother is driving. Dr. Boli does not recommend driving under the influence of Proust.