Lights in the night

1. Lights in the night UFO detections There are many things in the night sky- Learn to separate the junk from the treasure

2. False detections: atmospherics

3. False detections: Venus in the evening sky

4. A meteoroid’s typical speed is 50 km/s, so when it hits the Earth’s atmosphere, it heats up and begins to vaporize. What actually lands on the Earth? • micrometer-sized objects float down to the Earth; • millimeter-sized particles burn up in the mesosphere (shooting star); • centimeter-sized particles burn up as a fireball (rare); • meter-sized particles strike ground (very rare). 1,000 tons of meteoritic material hit the Earth every day. False detections: meteors

5. Slowly moving lights in the sky, that move slowly enough that you can have a conversation about it in real time, are the results of terrestrial space programs. • Satellites—slowly move overhead • Space junk—vary in brightness over several seconds They will wink out when they enter the Earth’s shadow. Aircraft have auxiliary lights, but be warned—planes do not always move rapidly across the sky! Night-flying helicopters, and even hot air balloons are possibilities! False detections: actual craft

6. October 13, 2010. A parent carrying helium balloons into a school classroom accidentally let several loose. These reflective mylar balloons hovered over the streets of NYC for over an hour. This freaked out the citizens of NYC. Pete Bryant, 32: I saw five or six lights shining in the sky. There was no way that thing was a balloon. There was something weird about it. Light just doesn’t reflect off balloons like that. If Martians were to land anywhere, New York is a much better location than some backwoods town in the Midwest. Tim Powell, 28: The most bizarre thing I've ever seen. It looked like a jellyfish made of lights that just hovered in the sky like it wanted to be seen. I was half expecting the aliens to beam down and introduce themselves. Richard Molina, 42, compared what he saw to the “creatures from ‘Predator.’ It freaked me out.” False detections: weird stuff

7. I expect you to do better. I also expect you to be able to make better observations, to help separate the trash from the junk. Your responsibility