Astrophysical fluid dynamics she pulls in her arms. These stars gradually slow down over the eons, but those bodies that are still spinning rapidly may emit radiation that from Earth appears to blink on and off as the star spins, like the beam of light from a turning lighthouse. This "pulsing" appearance gives some neutron stars the name pulsars. After spinning for several million years pulsars are drained of their energy and become normal neutron stars. Few of the known existing neutron stars are pulsars. Only about 1,000 pulsars are known to exist, though there may be hundreds of millions of old neutron
Beam bridge great distances; it only means that a series of beam bridges must be joined together, creating what is known as a continuous span. Beam bridge Beam bridges , also known as stringer bridges, are the simplest structural forms for bridge spans supported by an abutment or pier at each end. No moments are transferred throughout the support, hence their structural type is known as "simply supported". The simplest beam bridge could be a log (see log bridge), a wood plank, or a stone (see clapper bridge) laid across a stream. Bridges designed for modern infrastructure will usually be constructed of