Several bright lights appeared one at a time, and disappeared. Three different times over about 20-30 miles and 10 minutes as we droveWe were traveling on US 50, between Rocky Ford, Colorado, and La Junta, Colorado. A low flying light began to appear and get brighter and brighter, then another light about a hand length apart from the first light appeared in the same manner, and another. The first light then went out and another appeared. There were a total of 4-5 lights that were not all on at the same time. They lit up one after the other. They were yellowish white and smaller than a full moon, but at max intensity were brighter than a train light. They appeared for about 6-8 seconds. No pattern, and low, because I could see them through the windshield of the car. My wife had seen the same lights about 5 minutes prior close to Rocky Ford. She said that they had came on and disappeared so quickly that she had not mentioned them because she thought she was seeing things. I then realized that they were traveling east and I asked my wife and daughter to continue to look as we drove east. Then, we turned to go to North La Junta and I had them continue to look east. About 5 minutes had passed and we arrived at our destination. We were in a prairie area with a huge view of the sky. I told them that if there are mysterious lights we will see them. As we began to walk into our destination they appeared again low in the east, smaller and farther away. One light came on at a time and 5-7 lights came on and disappeared closer together than before. (They probably appeared closer together because they were farther away.) They seemed to be traveling about the speed of a helicopter. I told the family that if they were helicopters they were communicating with each other and to turn on lights one after the other. Also, they were traveling away from us, yet the lights seemed to be facing us and could get very bright. We did not hear any sound at any time.