Oort Limit
Encyclopedia
There are two definitions of the Oort limit:
- the outer boundary of the Oort cloudOort cloudThe Oort cloud , or the Öpik–Oort cloud , is a hypothesized spherical cloud of comets which may lie roughly 50,000 AU, or nearly a light-year, from the Sun. This places the cloud at nearly a quarter of the distance to Proxima Centauri, the nearest star to the Sun...
. The current estimate is about 100,000 astronomical units (15 trillion km, or 1.5 lightyears) from the Sun, which is approximately 1/3 of the distance to the nearest star (Alpha CentauriAlpha CentauriAlpha Centauri is the brightest star in the southern constellation of Centaurus...
). - the estimate of the local density of matter (mass per unit volume) in the Sun's vicinity.