Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Visually discerning the curvature of the Earth

Not Accessible

Your library or personal account may give you access

Abstract

Reports and photographs claiming that visual observers can detect the curvature of the Earth from high mountains or high-flying commercial aircraft are investigated. Visual daytime observations show that the minimum altitude at which curvature of the horizon can be detected is at or slightly below 35,000  ft, providing that the field of view is wide (60°) and nearly cloud free. The high-elevation horizon is almost as sharp as the sea-level horizon, but its contrast is less than 10% that of the sea-level horizon. Photographs purporting to show the curvature of the Earth are always suspect because virtually all camera lenses project an image that suffers from barrel distortion. To accurately assess curvature from a photograph, the horizon must be placed precisely in the center of the image, i.e., on the optical axis.

© 2008 Optical Society of America

Full Article  |  PDF Article
More Like This
Extended visual range during solar eclipses

Michael Vollmer and Joseph A. Shaw
Appl. Opt. 57(12) 3250-3259 (2018)

Below the horizon—the physics of extreme visual ranges

Michael Vollmer
Appl. Opt. 59(21) F11-F19 (2020)

Visual Observations and Spectral Investigations of the Earth’s Atmosphere Twilight Aureole from the Soyuz-5 Spacecraft

K. Ya. Kondratyev, B. V. Volynov, A. P. Galtsev, O. I. Smokty, and E. V. Khrunov
Appl. Opt. 10(11) 2521-2533 (1971)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (7)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Equations (3)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved