Binary number a separate "subtract" operation. Using two's complement notation subtraction can be summarized by the following formula: A − B = A + not B + 1 Multiplication in binary is similar to its decimal counterpart. Two numbers and can be multiplied by partial products: for each digit in , the product of that digit in is calculated and written on a new line, shifted leftward so that its rightmost digit lines up with the digit in that was used. The sum of all these partial products gives the final result. Since there are only two digits in binary, there are
Contact binary (small Solar System body) Contact binary (small Solar System body) A contact binary is a small Solar System body that is composed of two bodies that have gravitated toward each other until they touch. This means contact binaries have odd shapes. Comet Churyumov–Gerasimenko and Comet Tuttle are most likely contact binaries. Asteroids suspected of being contact binaries include the unusually elongated 624 Hektor and the bilobated 216 Kleopatra and 4769 Castalia. 25143 Itokawa, which was photographed by the "Hayabusa" probe, also appears to be a contact binary which has resulted in an elongated, bent body. About 10–15% of near-Earth asteroids larger than 200 meters