Apollo 17 photo: Courtesy of NASA
From space the earth looks beautiful and peaceful but every second the destiny human lives is finalized.
The Earth's population is now over 6 Billions and every time you take a breath about 4 people die. This adds up to 106 people every minute or 55,713,600 every year. In 100 years those now living will be all gone. Our Milky Way galaxy consists of 200,000,000,000 stars and that is probably how many people have died since the beginning of humanity 1 million years ago.
Where have they all gone? They have passed into the invisible dimension of the universe, probably at its non-spatial center where God's energies are forming a new dynamic universe. Here every soul meets Christ in his "Second Coming" and is judged according to the life he or she led.
Angels are part of Christ's Kingdom because they were created through Him and for Him and have been involved in history of the Universe from the beginning. "Are they not all ministering spirits sent to serve, for the sake of those who are to inherit salvation?" (Hb 1:14) They see God in all his glory and rejoicing carry out his plan of salvation. St. Basil tell us that "Beside each believer stands an angel as protector and shepherd leading him to life. " And so we join the Angels in praising Christ our King: Holy, Holy, Holy is the Lord God of hosts, heaven and earth a full of His glory.

The belief in the "Communion of Saints" means that there is community of Love (Charity), a sharing of spiritual goods between all the members of Christ's kingdom, those on earth, in heaven and purgatory.
The Martyrs, usually shown with the palm of victory in their hands, were the first to be venerated, followed by those whom the people believed lived holy lives. This means that we honor the saints and ask them to intercede with God for our temporal and spiritual needs.
We also venerate the relics of the saints because their bodies were dwelling places of the Holy Spirit.
In the Eastern Church there developed the veneration of icons (images) which were defended by the Church in 8th century against the Iconoclasts who successfully destroyed many images because they considered them idolatry. The Church justified its use in view of the fact that Christ became Man and is now worshipped through His humanity. The Icon makes present to the believer the beauty of the heavenly reality leading him/her to prayer and contemplation.
"I will sing about the second realm
where man's soul goes to purify itself
and become worthy to ascend to heaven."
(Dante:Purgatory I:4)
Why do we pray for our loved ones who have died? Death brings us face to face with our destiny in God's plan and we are aware that this is uncertain destination. We hope to go to heaven yet many of us, aware of our sinfulness and imperfection, realize that we may have to pass through a period of purification. When this happens, the glory of God burns into our souls as fire and dynamics of "place" will surely provide its own pain. Some say they do not believe in Purgatory, but then, there is no sense in praying. If our loved ones are in heaven, they do not need our help; if they are in Hell, we cannot help them.
Genghis Khan, the fiercest conqueror of all time, as death was approaching said to his followers not to lament at his death because death cannot be frightened away by screaming.
"Instead...pray to God to be gracious to me;
say prayers that will delight my soul." 45
At funerals we expresses our belief in the communion of saints thus:
"May the angels lead you into paradise;
may the martyrs come to welcome you and take you to the holy city,
the new and eternal Jerusalem."
(Sung by Gina Demalijaj in Latin)
Sorry, those in Hell have been cast out of Christ's Kingdom and for them, there is nothing we can do.