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Don Pettit, NASA\u2019s oldest active astronaut, returned to Earth on April 20, the day he turned 70 years old. That concluded his fourth trip to space \u2014 a busy 220 days at the International Space Station.<\/p>\n
Like other crew members on the space station, Mr. Pettit conducted experiments, talked with students and exercised for hours to maintain his health and to stave off loss of bone density. But the most eye-catching work he performed in orbit was his photography.<\/p>\n
Most people on Earth will never get a chance to go to space. \u201cI could try to give them a glimpse through my imagery,\u201d Mr. Pettit said during a news conference a couple of weeks after his return.<\/p>\n
Mr. Pettit noted that hard-core photographers always want to have a camera in hand. \u201cI could look out the window and just enjoy the view,\u201d he said. \u201cBut when I\u2019m looking out the window, just enjoying the view, it\u2019s like, \u2018Oh, wow, a meteor. Oh, wow. Look at that. Man, there\u2019s a flash there. What\u2019s that?\u2019 And, \u2018Oh, look at that, a volcano going off.\u2019 It\u2019s like, \u2018OK, where\u2019s my camera? I got to record that.\u2019\u201d<\/p>\n
Sometimes he set up five cameras at once in the space station\u2019s cupola module, where seven windows provide panoramic views of space and Earth.<\/p>\n<\/div>\n<\/div>\n
Space photography is often much like night photography. Stars are dim, and exposures lasting seconds or minutes are needed to gather enough photons. But in orbit, nothing is sitting still. The space station is zooming around Earth at about five miles per second, and the Earth is also rotating.<\/p>\n
Sometimes, Mr. Pettit took advantage of the motion for artistic beauty \u2014 lights below blurring into glowing lines, while the stars above traced arcs in the sky.<\/p>\n
\u201cI think these are a blend of both science and art,\u201d Mr. Pettit wrote on X. \u201cThere is so much techno-geek stuff to see, or you can simply sit back and think \u2018How cool.\u2019\u201d<\/p>\n
Other times, the camera was mounted on an \u201corbital sidereal tracker\u201d \u2014 a homemade device Mr. Pettit brought up from Earth that would pivot slowly to counteract the motion of the space station so that the lens remained pointed at a particular spot in the sky.<\/p>\n
The tracker enabled a 10-second exposure to capture a crystal clear image of the Milky Way above a cloudy Pacific Ocean just before sunrise. The blue-purple glow emerges from the scattering of sunlight off nitrogen in Earth\u2019s atmosphere.<\/p>\n<\/div>\n<\/div>\n
The sidereal tracker also enabled the image below, taken through the window of a docked SpaceX Crew Dragon spacecraft.<\/p>\n
The two dwarf galaxies in the image are the Large and Small Magellanic Clouds. On the cosmic scale, they are among our Milky Way galaxy\u2019s closest neighbors.<\/p>\n<\/div>\n<\/div>\n
In April, Mr. Pettit recorded this video of the ethereal rhythmic pulsations of auroras \u2014 the glowing light emitted when molecules in the atmosphere are bombarded by high-energy particles from the sun.<\/p>\n<\/div>\n<\/div>\n
Sometimes the colorful lights were made by human activities, not cosmic phenomena. The green streaks in this picture are almost the same color as auroras, but they are the lights used by fishing boats off Thailand to attract squid.<\/p>\n<\/div>\n<\/div>\n
With his camera pointing down at Earth, Mr. Pettit recorded lightning in the upper atmosphere above the Amazon basin in South America. For the video, the time was stretched in length to 33 seconds from about 6 seconds, revealing more structure in the flashes.<\/p>\n<\/div>\n<\/div>\n
The Betsiboka River in Madagascar reminded Mr. Pettit of blood vessels of the eye.<\/p>\n<\/div>\n<\/div>\n
Metropolitan areas light up at night, as do wildfires.<\/p>\n<\/div>\n<\/div>\n
Mr. Pettit also took advantage of opportunities to capture the comings and goings of spacecraft from Earth \u2014 including a test launch of a SpaceX Starship rocket from Texas last November \u2026<\/p>\n
\u2026 and the docking of a SpaceX Dragon spacecraft carrying cargo to the space station in December.<\/p>\n<\/div>\n<\/div>\n
During his off-duty time, Mr. Pettit also concocted fun science experiments. One showed electrically charged water droplets dancing around a Teflon knitting needle. \u201cI want to do things in space that you can only do in space,\u201d he said. \u201cAnd I\u2019ll worry about catching up with TV programs and things like that after I come back.\u201d<\/p>\n<\/div>\n<\/div>\n
In another experiment, he injected food coloring into a sphere of water, creating a globule that somewhat resembled the planet Jupiter, or a very pretty marble.<\/p>\n<\/div>\n<\/div>\n
Mr. Pettit also dissolved an antacid tablet within a water sphere. Without gravity to make the bubbles rise and easily escape from the water, the patterns of pop, plop, fizz, fizz are completely different in space.<\/p>\n<\/div>\n<\/div>\n
He also froze thin wafers of water ice at minus 140 degrees Fahrenheit. \u201cWhat would you do with such a freezer in space?\u201d he wrote on X. \u201cI decided to grow thin wafers of water ice for no more reason than I\u2019m in space and I can.\u201d<\/p>\n
Photographing the ice wafers through polarizing filters revealed intricate crystal patterns.<\/p>\n
Mr. Pettit is the oldest current NASA astronaut, but he is not the oldest person to go to orbit. That was John Glenn, who was the first American astronaut to circle the Earth in 1962, and then flew again in 1998 on the space shuttle Discovery at the age of 77.<\/p>\n<\/div>\n<\/div>\n
Mr. Pettit is not even the oldest person to spend time at the International Space Station. A private astronaut, Larry Connor, was 72 years old when he spent two weeks there in 2022 as part of a mission operated by Axiom Space of Houston.<\/p>\n
\u201cI\u2019m only 70, so I\u2019ve got a few more good years left,\u201d Mr. Pettit said during the news conference. \u201cI could see getting another flight or two in before I\u2019m ready to hang up my rocket nozzles.\u201d<\/p>\n<\/div>\n<\/div>\n