The Earth passes very close to the orbit of the asteroid 1999 AN10 twice per year, but whether or not this asteroid can have a close approach depends upon the timing of its passage across the ecliptic plane. Among the possible orbits there are some with a close approach in 2027. The period of the asteroid may be perturbed in such a way that it returns to an approach to the Earth at either of th...

When professor Antony Hewish of Cambridge University set out with his graduate student Jocelyn Bell to study the effects of interplanetary scintillation in the latter part of 1967 he had no idea they would make one of the most important astronomical discoveries of their time. The association of their discrete radio signal with a Pulsar, then only a theorized entity, initiated an era of great in...