What is the rising sign of Scorpio?

Any constellation may be the rising constellation of Scorpio.

Ascending constellation, also known as birthday constellation, is the constellation where the eastern horizon is located when an individual is born. Its change depends on the time and place of birth, so any constellation is possible.

As long as you know your detailed birthday, including the date and time, you can check it against the astrolabe and be sure to get the exact time and minute.