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Many students in India know Kalpana Chawla's name. Fewer know what she actually did as an engineer before she became an astronaut, or how the physics in your gravitation chapter describes the flights she made. This post sets out the verified facts of her career, works through the orbit numbers from her first mission, and ends with what a student can take from her way of working.
Who was Kalpana Chawla?
Her official NASA biography gives the outline. She was born in Karnal, India, and graduated from Tagore School, Karnal, in 1976. She took a bachelor's degree in aeronautical engineering from Punjab Engineering College in 1982, a master's in aerospace engineering from the University of Texas in 1984, and a doctorate in aerospace engineering from the University of Colorado in 1988.
She was also a pilot. The same biography lists a flight instructor's licence with airplane and glider ratings and commercial pilot's licences for single- and multi-engine land and seaplanes, and notes that she enjoyed flying aerobatics.
What did she work on before NASA selected her?
In 1988 she joined NASA Ames Research Center to work on powered-lift computational fluid dynamics: simulating the complex air flows around aircraft such as the Harrier when they hover close to the ground. She then worked on mapping flow solvers onto parallel computers. In 1993 she joined Overset Methods Inc. in California as Vice President and Research Scientist, working on simulations of several moving bodies and on aerodynamic optimisation.
That is worth noticing. Her route to space ran through years of computing and fluid mechanics, not a single leap. NASA selected her in December 1994, and she reported to the Johnson Space Center in March 1995 as an astronaut candidate.
What happened on her two missions?
On STS-87, from 19 November to 5 December 1997, she was a mission specialist and the prime robotic arm operator. The flight carried microgravity experiments and observations of the Sun's outer atmosphere. According to her biography, STS-87 made 252 orbits of the Earth, travelling 6.5 million miles in 376 hours and 34 minutes.
Her second flight, STS-107, ran from 16 January 2003. It was a 16-day science mission in which the crew worked in two shifts around the clock and carried out about 80 experiments. On 1 February 2003 Columbia and its crew were lost during entry, 16 minutes before the scheduled landing. Across the two flights she logged 30 days, 14 hours and 54 minutes in space, and she was posthumously awarded the Congressional Space Medal of Honor.
The Columbia Accident Investigation Board found that during launch a piece of insulating foam from the bipod ramp of the external tank struck the leading edge of the left wing. The damage gave hot gas a path into the wing during entry. The Board also examined NASA's organisational culture and how engineers' concerns reached managers.
What does orbit physics say about her first flight?
The STS-87 numbers make a good Class 11 gravitation problem, and they let you check NASA's figures against each other.
Step 1: the period. 376 h 34 min is 22,594 minutes. Divided by 252 orbits, that is about 89.7 minutes per orbit, or 5,380 s.
Step 2: the orbital radius. For a circular orbit, gravity provides the centripetal force: GMm/r² = m(4π²r/T²), so r³ = GMT²/4π². NASA's Earth fact sheet gives GM = 3.986 × 10¹⁴ m³/s² and a mean radius of 6,371 km. Then r³ = (3.986 × 10¹⁴ × 5,380²) / 39.48 ≈ 2.92 × 10²⁰ m³, so r ≈ 6,636 km. Subtracting Earth's radius gives an average height of roughly 265 km.
Step 3: the speed, two ways. From the orbit: v = 2πr/T = 2π × 6.636 × 10⁶ / 5,380 ≈ 7,750 m/s. From the distance NASA quotes: 6.5 million miles is about 1.05 × 10¹⁰ m, covered in 1.356 × 10⁶ s, which gives about 7,720 m/s. The two estimates agree to within half a percent, which is as close as rounded figures allow.
Two common mistakes: using the height (265 km) instead of the distance from Earth's centre in r³ = GMT²/4π², and forgetting to convert hours to seconds. Our guide to satellite and gravitation problems has more practice of this kind.
If orbits feel abstract, it helps to watch radius, speed and period change together. The Fermi Simulation Lab has interactive simulations for ideas that are easier to see than to read.
What can a student take from how she worked?
Build depth before the headline. Her biography is mostly about fluid dynamics, parallel computing and optimisation. The years of careful engineering came first.
Keep learning by doing. She held several pilot ratings and flew for pleasure. Hands-on practice sat alongside theory.
Check numbers against each other. As in the worked example, two independent routes to the same answer catch most mistakes.
Take the long route if needed. Karnal, Chandigarh, Texas, Colorado, Ames, Houston: each step was a qualification or a job, not a shortcut.
India's own space story has its engineers too; read about Satish Dhawan and Indian aerospace next.
Try it yourself: redo the worked example for an orbit with a 92-minute period and find its height.
