What would happen if the Earth orbited the sun but did not rotate on it's axis?

Answer 1

-- You would see the sun rise and set once a year.

-- The sun would rise in the west, cross the sky really slowly, and set in the east 6 months later.

-- Then you would see stars rise in the west, cross the sky really slowly, and set in the east six months later.

-- During that time, you would see the moon rise in the west every 27.32 days, cross the sky slowly, and set in the east about 13-1/2 days later. (A 'day' meaning 24 hours, which you could only tell by your clock, since the sun would not help in telling time).

-- During the 6 months of sun-down, you would see a grand total of 1/2 of the stars and constellations. If you ever wanted to see the other half, you would need to travel to the other side of the earth.

-- But star-gazing would probably never be an important facet of life. In order to do it, you have to be outdoors, which would be a really cold experience during the 6 months when the sun stayed down.

Answer 2

-- Wherever you live, you would see the sun rise in the west, cross the sky very

slowly, and set in the east six months later. Every place on Earth would have six

months of daylight and six months of dark.

-- During the dark six months, you would see half of all the stars there are,

standing rock-steady in your sky. They would never rise or set, they would

always be the same stars, in the same places, and you could see only half

of them during your lifetime, unless you traveled to another place on Earth

to see more stars.

-- If you keep the Moon in your fantasy, then the occurrence of lunar and solar eclipses

remains exactly the same as it is now. The appearance of lunar eclipses doesn't change

at all, but solar ones can become considerably longer as seen from any one place.

-- Geostationary TV satellites would not be possible. The only people who could

use any kind of satellite would be those who could afford a movable, tracking

dish. There would be so few of those that no viable market for satellite TV could

grow, satellite TV would not exist, and the rest of us would have nobody to envy.

-- There would be hugely greater rates of insomnia, during the 6 months when

the sun never sets, and of depression, during the 6 months when the sun never

rises. The bipolar club would be much less exclusive ... everybody could join in,

an annual cycle would be very common, but the peaks in each community would

be slightly offset from those in the next community just down the road.

-- Every place on Earth would have 6 months of getting warmer and 6 months

of getting colder. Just as every place has now, but it would be continuous, not

broken up into alternating 12-hour slivers. Weathermen would not need to go

on TV every day, or on radio every ten minutes, as they do now. They would

only be predicting the highest and lowest temperatures expected during the

next year, not during the next day.

-- There would be no effect due to the non-perpendicularity ("tilt") of the

Earth's axis relative to the plane of its orbit. If it didn't rotate, then there

would be no "axis", and thus no "tilt".

That's the way I see it. The question is fascinating.

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Nearly there but I'm afraid you've made a basic mistake. The mechanism you describe is of the Earth rotating on its axis at the same rate as its orbit, i.e. one Earth Day lasting a whole year. The Moon behaves like this in its orbit around the Earth.

If the Earth did not rotate at all, as asked, one half of it would face the Sun, the other half would be in darkness, permanently. If it still has its present atmosphere, that would create a broad twilight band from Pole to Pole, and combine with latitude angles to give at least some temperature grading from Equatorial to (Ant)Arctic on the sun-lit face.