The BUN is roughly one-half of the blood urea (R). Normal human adult blood should contain between 5 to 20 mg of urea nitrogen per 100 ml (5â20 mg/dL) of blood, or 1.8 to 7.1 mmol urea per liter (R). To convert from mg/dL of blood urea nitrogen to mmol/L of urea, multiply by 0.357.
The 'dark' side of the moon. The moon orbits the Earth once every 27.322 days. It also takes approximately 27 days for the moon to rotate once on its axis. As a result, the moon does not seem to be spinning but appears to observers from Earth to be keeping almost perfectly still. Scientists call this sychronous rotation. The side of the moon that perpetually faces Earth is known as the near side. The opposite or back side is the far side.
The Moon orbits Earth in the prograde direction and completes one revolution in approximately 27.322 days (a sidereal month). Earth and the Moon orbit about their barycentre (common center of mass), which lies about 4600 km from Earth's center (about three quarters of the radius of Earth). On average, the Moon is at a distance of about 385000 km from Earth's center, which corresponds to about 60 Earth radii. With a mean orbital velocity of 1.023 km/s, the Moon moves relative to the stars each hour by an amount roughly equal to its angular diameter, or by about 0.5Â°. The Moon differs from most satellites of other planets in that its orbit is close to the plane of the ecliptic, and not to Earth's equatorial plane. The plane of the lunar orbit is inclined to the ecliptic by about 5.1Â°, whereas the Moon's spin axis is inclined by only 1.5Â°.