What is the main star of the seventh house?

The main star of the palace is the congenital main star of the constellation that falls on the head line of each palace, and the main star of the first palace is particularly important, which is called the main star of the whole chart. For example, the main star of the rising ram is Mars, the head line of the second house falls in Taurus, and the main star of the second house is Venus; The first line of the third house falls in Gemini, and the main star of the third house is Mercury. The head line of the fourth house falls in Cancer, and the main star of the fourth house is the moon. The head line of the fifth house falls in Leo, and the main star of the house is the sun; The first line of the sixth house falls in Virgo, and the main star of the sixth house is Mercury. The head line of the seventh house falls in Libra, and the main star of the seventh house is Venus. The head line of the eighth house falls on Scorpio, and the main star of the eighth house is Pluto; The head line of the ninth house falls in Sagittarius, and the main star of the house is Jupiter; The first line of the tenth house falls in Capricorn, and the main star of the tenth house is Saturn; The first line of the eleventh house falls in Aquarius, and the main star of the eleventh house is Uranus; The head line of the twelfth house falls in Pisces, and the main star of the twelfth house is Neptune.