SCIENCE BEHIND THE SCENES
Long Exposures Stars and Earth
Photographic Process: Multiple long (20 second exposures) taken from fixed mount in ISS cupola. Photo editing software used to layer (composite) 6 images into a single frame. Photographer edited individual elements from selected layers for visual impact and artistic effect. Colors are meant to reflect viewing experience.
Physics in the Photo:
• Space Station Rotation – ISS cupola points nadir (toward earth) as it orbits the earth. It is turning on its own axis as it orbits.
• Orbital speed
• Low earth orbit
Elements to Identify:
• stars• lightning • city lights • atmosphere on edge
Points to Ponder:
• Why are streaks different colors?
• What makes the atmosphere appear green?
• Star trails are curved, which direction was the photographer looking? N - S - E - W
• What are the white flashes?
Technology of Living in Space
Photographic Process: Single exposure, zoom lens set to 45mm.
Physics in the Photo:
• Solar arrays rotate a station orbits earth to convert light into electricity.
Elements to Identify:
• Solar arrays
• Space to Ground antenna (spare)
• Radiators
• Truss assembly
Points to Ponder:
• Why do solar arrays need to rotate?
• How does the station get power when earth blocks the sun?
Capturing the Moment:
Solar Photography
Photographic Process: Floating in the cupola, photos were taken with a hand held the camera using 1200 mm lens equipped with solar filter. Many practice photos were taken in advance to be able to capture venus as it passed between the sun and the Space Station.
Physics in the Photo: Planet Venus moves across the face of the sun about once every hundred years transiting two times within about an 8 to 10 year period.
Elements to Identify:
Planet venus • sun spots
Points to Ponder:
• How big is the sun compared to venus?
• Why did astronaut Pettit use a special solar filter?
• How big is a sun spot compared to venus?
Earth at Night
Photographic Process: Multiple photographs were taken in sequence as ISS flew over the East Coast of the United States. Later overlapping images were combined into a single image. Taken in 2003, these photographs required a barn door tracker to follow lights on the ground.
Physics in the Photo: Individual street lights merge together to be seen over 350 km (220 miles) in space miles in space. ISS covers 8 kilometers (5 miles) per second .
Elements to Identify:
Washington D.C. • Baltimore • Philadelphia • New York City • Long Island • Providence, Rhode Island • Cape Cod • Boston
Points to Ponder:
• How do city lights inform us about where people live?
Self Portrait with Earth
Photographic Process: Camera mounted in the Russian segment and set to take a frame every few seconds. Astronaut Pettit flew 75 meters (250 ft) to the cupola while the camera continued to capture his image. A second set of photos were taken of the earth and stars with the camera refocused. Later two images were combined.
Physics in the Photo: Earth, stars and the ISS are visible. Light reflected from the earth illuminates the cupola of the Space Station.
Elements to Indentify:
Cupola • protective covers • earth’s atmosphere
Points to Ponder:
•What is like to fly in the space station?
• Which way is up?
• Why does the atmosphere appear orange and green?