Spying on the Government in Area 51

(By A.C. Thompson) - It started with an e-mail inviting me to join an expedition to Area 51, the secret military site in the Nevada backcountry.

'Let me be clear about this,' wrote Trevor Paglen, the 30-year-old geographer leading the trek. 'The trip will not be easy. The weather is unpredictable – it could be really hot or really cold, or (most likely) both.... If you are not in reasonable shape, or are without proper equipment, you will die. Seriously.'

Despite the less-than-inviting invitation, I was intrigued. For five decades Area 51 has been the military's heart of darkness, the core of its 'black world' of classified research and development, a place that appears on no maps, and, officially, has no name....