Home Remedies for Whiter Teeth. Some people still prefer the age-old home remedy of baking soda and a toothbrush to gently whiten teeth at home. Also, some foods such as celery, apples, pears, and carrots trigger lots of saliva, which helps wash away food debris on your teeth.
Roche limit. n. The smallest distance at which a natural satellite can orbit a celestial body without being torn apart by the larger body's gravitational force. The distance depends on the densities of the two bodies and the orbit of the satellite.
Once Phobos gets down to an altitude of only 7000 km above the center of Mars (or 3,620 km above its surface), it will enter whatâs known as the Roche limit. At this point, the tidal forces of Mars will tear Phobos apart, turning it into a ring that will continue to spiral into Mars.