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.
NASA. By Neptune's diamond oceans! Future humans won't have to wait to travel to Pandora for the chance to mine unobtanium, because Neptune and Uranus may have diamond icebergs floating atop liquid diamond seas closer to home. The surprise finding comes from the first detailed measurements of the melting point of diamond, Discovery News reports.