1 To be safe, USDA recommends that all pressure canners must be vented 10 minutes before they are pressurized. 2  To vent a canner, leave the vent pipe (steam vent) uncovered (or manually open the petcock on some older models) after you fill the canner and lock the canner lid in place.
There would be no place to land, and the ship would get crushed under Neptune's massive gravity, or ripped apart by its weather. To get there, we would have to build a space ship that can travel extremely fast. Then it would have to orbit Neptune or be incredibly durable to get inside of the planet. It would also need a large supply of O2, food and water.
Comet Smacked Neptune 200 Years Ago, Data Suggests. by Denise Chow, SPACE.com Staff Writer | July 23, 2010 02:48pm ET. New measurements performed by the European Space Agency's Herschel infrared space telescope indicate that a comet may have hit Neptune, the outer-most planet in our solar system, two centuries ago.