The Great Courses (Firm)
Publisher
The Great Courses
Pub. Date
2024.
Language
English
Description
Contrary to popular belief, the seasons are not caused by changes in the distance between Earth and the Sun over the course of a year. Instead, the tilt of Earth's axis of spin relative to the axis of its orbital plane produces seasons.
5) Understanding the Universe: An Introduction to Astronomy, 2nd Edition: Episode 7The Celestial Sphere
Publisher
The Great Courses
Pub. Date
2024.
Language
English
Description
As Earth rotates on its axis and orbits the Sun, the night sky changes over a 24-hour period, as well as throughout the year. This lecture explains how to locate celestial bodies and why the sky appears different from place to place.
7) Understanding the Universe: An Introduction to Astronomy, 2nd Edition: Episode 21The Colors of Stars
Publisher
The Great Courses
Pub. Date
2024.
Language
English
Description
The surface temperature of a star determines its apparent color. The hottest stars are bluish in color, and the coldest stars are reddish; stars at intermediate temperatures appear white. The Sun is a white star.
Publisher
The Great Courses
Pub. Date
2024.
Language
English
Description
Astronomers obtain most of their information through the analysis of light. This lecture introduces the electromagnetic spectrum and the technique of spectroscopy, in which light is dispersed into its component colors, as in a rainbow.
14) Understanding the Universe: An Introduction to Astronomy, 2nd Edition: Episode 23Modern Telescopes
Publisher
The Great Courses
Pub. Date
2024.
Language
English
Description
Today's telescopes are designed to provide huge light-gathering mirrors at relatively low cost. The mirrors focus light from distant objects onto sensitive electronic detectors that are far more efficient than traditional photographic film.
Publisher
The Great Courses
Pub. Date
2024.
Language
English
Description
Though less massive than Jupiter and Saturn, Uranus and Neptune are similar in that they consist mostly of hydrogen and helium. Both have bizarre magnetic fields that are highly tilted relative to the planet's rotation axis and offset from the planet's center.
16) Understanding the Universe: An Introduction to Astronomy, 2nd Edition: Episode 28Mercury and Venus
Publisher
The Great Courses
Pub. Date
2024.
Language
English
Description
Though broadly similar to Earth, Mercury and Venus differ in detail. Mercury has a negligible atmosphere and is heavily cratered. Venus has an incredibly thick atmosphere and suffers from an extreme greenhouse effect that makes it intensely hot.
17) Understanding the Universe: An Introduction to Astronomy, 2nd Edition: Episode 11More Eclipse Tales
Publisher
The Great Courses
Pub. Date
2024.
Language
English
Description
Solar eclipses also come in annular and hybrid varieties, reflecting the varying distance of the Moon from Earth. A famous total solar eclipse in 1919 provided observational evidence for Einstein's general theory of relativity.
Publisher
The Great Courses
Pub. Date
2024.
Language
English
Description
According to legend, Newton saw a falling apple and realized that the force that pulled it toward Earth also pulled on the Moon, keeping it in its orbit. Building on the work of Kepler and Galileo, he revolutionized astronomy with his law of universal gravitation and laws of motion.