Larger craters can have terraces, central peaks, and multiple rings. Copernicus is a large crater (93 kilometers or 60 miles wide) on the Moon. The inner walls of the crater have collapsed to form a series of step-like terraces, and a central peak is visible in the center of the image. Apollo 17 image courtesy of NASA. A complex crater in the northern region of Mars.
Self-published authors could be paid as little as $0.006 per page read under new rules planned by Amazon. Writers who make their works available through Amazonâs Kindle Owners Lending Library, and a similar service called Kindle Unlimited, will no longer be paid per copy downloaded following a move announced last week.
Letâs break down the math to see whether you plow through enough books regularly to justify the cost. At $9.99 per month, Kindle Unlimited costs about $120 per year. E-books on Amazon can vary wildly in price, from $0.99 to hundreds of dollars. During 2013, e-books on the Digital Book World best-sellersâ list mostly sold for between $7 and $8 on average (the price in the most recent recorded week in 2014 was $7.52).