Eris' size resulted in its discoverers and NASA labelling it the solar system's tenth planet. This, along with the prospect of other similarly sized objects being discovered in the future, stimulated the International Astronomical Union (IAU) to define the term planet more precisely. Under a new definition approved on August 24, 2006, Eris was designated a dwarf planet along with Pluto and Ceres.
Best Answer: it depends on a few things~...but the longest time a human can stay upside down is 2 days.. If your heart is reasonably healthy and you aren't restricted, then you shouldn't pass out at all, any more than you would laying down or standing up.
3. How long can the brain go without oxygen before serious damage occurs? After five to ten minutes of not breathing, you are likely to develop serious and possibly irreversible brain damage. The one exception is when a younger person stops breathing and also becomes very cold at the same time. This can occur when a child is suddenly plunged into very cold water and drowns. In this situation, survival after more than 30 minutes has been known to occur. Return to the list of Frequently Asked Questions >>