Concerning whether the world will be aware of the Church's departure, the Biblical patterns of rapture imply the affirmative.
With the exception of Enoch's rapture (whose audience, or lack thereof, is not specified), virtually every rapture in the Bible is a witnessed and realized event:
the rapture of Elijah
“As they were going along and talking, behold, there appeared a chariot of fire and horses of fire which separated the two of them. And Elijah went up by a whirlwind to heaven. Elisha saw it and cried out, “My father, my father, the chariots of Israel and its horsemen!” And he saw Elijah no more. Then he took hold of his own clothes and tore them in two pieces.” (2 Kings 2:11–12)
the rapture of Jesus (commonly referred to as His ascension)
“So then, when the Lord Jesus had spoken to them, He was received up into heaven and sat down at the right hand of God.” (
"He was lifted up while they were looking on, and a cloud received Him out of their sight. And as they were gazing intently into the sky while He was going, behold, two men in white clothing stood beside them. They also said, “Men of Galilee, why do you stand looking into the sky? This Jesus, who has been taken up from you into heaven, will come in just the same way as you have watched Him go into heaven.”” (Mark 16:19, Acts 1:9–11)
the rapture of Phillip
“When they came up out of the water, the Spirit of the Lord snatched Philip away; and the eunuch no longer saw him, but went on his way rejoicing. But Philip found himself at Azotus, and as he passed through he kept preaching the gospel to all the cities until he came to Caesarea.” (Acts 8:39–40)
the rapture of the two witnesses
“Those from the peoples and tribes and tongues and nations will look at their dead bodies for three and a half days, and will not permit their dead bodies to be laid in a tomb. And those who dwell on the earth will rejoice over them and celebrate; and they will send gifts to one another because these two prophets tormented those who dwell on the earth. But after the three and a half days, the breath of life from God came into them, and they stood on their feet; and great fear fell upon those who were watching them. And they heard a loud voice from heaven saying to them, “Come up here.” Then they went up into heaven in the cloud, and their enemies watched them.” (Revelation 11:9–12)
With the exception of Enoch's rapture (whose audience, or lack thereof, is not specified), virtually every rapture in the Bible is a witnessed and realized event:
the rapture of Elijah
“As they were going along and talking, behold, there appeared a chariot of fire and horses of fire which separated the two of them. And Elijah went up by a whirlwind to heaven. Elisha saw it and cried out, “My father, my father, the chariots of Israel and its horsemen!” And he saw Elijah no more. Then he took hold of his own clothes and tore them in two pieces.” (2 Kings 2:11–12)
the rapture of Jesus (commonly referred to as His ascension)
“So then, when the Lord Jesus had spoken to them, He was received up into heaven and sat down at the right hand of God.” (
"He was lifted up while they were looking on, and a cloud received Him out of their sight. And as they were gazing intently into the sky while He was going, behold, two men in white clothing stood beside them. They also said, “Men of Galilee, why do you stand looking into the sky? This Jesus, who has been taken up from you into heaven, will come in just the same way as you have watched Him go into heaven.”” (Mark 16:19, Acts 1:9–11)
the rapture of Phillip
“When they came up out of the water, the Spirit of the Lord snatched Philip away; and the eunuch no longer saw him, but went on his way rejoicing. But Philip found himself at Azotus, and as he passed through he kept preaching the gospel to all the cities until he came to Caesarea.” (Acts 8:39–40)
the rapture of the two witnesses
“Those from the peoples and tribes and tongues and nations will look at their dead bodies for three and a half days, and will not permit their dead bodies to be laid in a tomb. And those who dwell on the earth will rejoice over them and celebrate; and they will send gifts to one another because these two prophets tormented those who dwell on the earth. But after the three and a half days, the breath of life from God came into them, and they stood on their feet; and great fear fell upon those who were watching them. And they heard a loud voice from heaven saying to them, “Come up here.” Then they went up into heaven in the cloud, and their enemies watched them.” (Revelation 11:9–12)
