In the last century, David Livingstone spent 14 years exploring unknown Africa. In the next century, there will be people prepared to devote that sort of time to exploring the cosmos; they will be right out there, telling the people back home what they are discovering. They might even pick up signals from other intelligent life, once they are well away from the electronic din of our planet.
And the cost of it all? Once we have a saner economic system, caring for the planet and adventuring beyond it will both be affordable.