What is the lowest altitude you can see stars in daylight is a question I have wondered about because of the well documented black starless daytime sky seen at high altitude. I can’t find any written reference to seeing stars in daylight from high altitude aircraft, balloons or near Earth orbiting craft such as the International Space Station (ISS). One reason I have seen put forward as to why it is difficult to see stars from the ISS in daylight is the glare of the Sun blots out the stars just like a full moon does when viewing the sky from the Earth at night. It seems a waste that adjustable shades couldn’t be fitted to the upper window(s) of the ISS to deal with this glare. Another reason is the bright lighting inside the ISS, but could I suggest a blackout curtain around the window or local light switch? The only written example of seeing stars in daylight I found is from cislunar space (the space between Earth and Moon). I would like to know if anyone has found an example of seeing stars in daylight at an altitude below this. My findings are below.
Google: Professor Brian Cox English Electric Lightning flight
Professor Brian Cox reaches 60,000ft (18km) demonstrating the deep dark blue sky at this altitude. This was filmed in 2009.
https://www.youtube....h?v=qwgfU228clE
Google: James May on the edge of space
James May finally reaches 70,000ft, where he looks down at the curvature of the earth, and upwards into the black infinity of space. This was filmed in 2009.
https://www.youtube....h?v=jIJRoj2qwsc
Google: Kittinger for National Geographic magazine
Extract: By Capt. Joseph W. Kittinger, Jr., USAF, for National Geographic magazine:
Overhead my onion-shaped balloon spread its 200-foot [61-meter] diameter against a black daytime sky. More than 18 1/2 miles [30 km] below lay the cloud-hidden New Mexico desert to which I shortly would parachute.
It was about 0700 local the Excelsior 3 was launched with Capt. Joeseph W. kittinger, Jr. USAF on board , lifted by a helium balloon to 102,800ft, (31.3km), (19.45 statute miles), on 16 Aug 1960, above New Mexico.
https://news.nationa...kydive-science/
Google: alan eustace ny times
Extract of NY Times article:
By Alan Eustace, 57, a senior vice president of Google:
“It was beautiful. You could see the darkness of space and you could see the layers of atmosphere, which I had never seen before.”
It was dawn Oct. 24, 2014 when Alan Eustace was lifted from an abandoned runway at Roswell airport, New Mexico by a balloon filled with 35,000 cubic feet of helium.
Mr Eustace’s maximum altitude was initially reported as 135,908 feet but based on information from two data loggers, the final number submitted to the World Air Sports Federation was 135,890 feet, (41.42km), (25.74 statute miles).
The previous altitude record was set by the Austrian daredevil Felix Baumgartner, who jumped from 128,100 feet (39.05km), (24.26 statute miles), on Oct. 14, 2012, New Mexico.
https://www.nytimes....rld-record.html
Google: An interview with Apollo 14 astronaut
Extract from: an interview with Apollo 14 astronaut Dr. Edgar Mitchell
by Sarah E. Truman (Editor of Ascent magazine)
Sarah E. Truman (editor of ascent magazine): In 1971, as you pulled away from the Moon and made your way back to Earth, what did it feel like to be in the space between worlds?
Dr. Edgar Mitchell : I’ll have to set up the story for you just a little bit. The spacecraft was oriented perpendicular to the plane that contains the Earth, the Moon and the Sun. Not flying perpendicular to that plane – but moving through it back to Earth. The spacecraft was rotating to maintain the thermal balance of the Sun. What that caused to happen was that every two minutes, with every rotation, we saw the Earth, the Moon and the Sun as they passed by the window. The 360-degree panorama of the heavens was awesome and the stars are ten times as bright and, therefore, ten times as numerous than you could ever see on a high mountaintop on a clear night. It was overwhelmingly magnificent.
http://ascentmagazin...issueID=30.html