speed of the earth around the sun is it the same during winter and summer?

Question

the earth is closer to sun during the northern hemisphere winter so its faster but would be right to assume that its travels just as fast during the northern hemisphere summer,considering that the axis it travels in is elliptical,so guessing during the summer its still the same distance away....right or wrong?

Answer 1

Kepler's 2nd Law of Planetary Motion states that a planet will sweep out equal areas in equal time.

SEE THE DIAGRAM IN THE LINK BELOW

The earth is at perihelion (its near point to the Sun) in the first few days of January and at aphelion (its furthest point from the Sun) in the first few days of July, every year (the date can vary by one or two days).

Here are the figures:

Aphelion distance: 152,097,701 km
(1.016 710 333 5 AU)
94,509,130 miles

Perihelion distance: 147,098,074 km
(0.983 289 891 2 AU)
91,402,725 miles

The distances vary by up to 5 million kilometres or 3 million miles.

From July onwards the earth starts to speed up as it draws nearer to perihelion in January and starts to slow down again once it passes perihelion.

Max. orbital speed: 30.287 km/s
(109,033 km/h)
Min. orbital speed: 29.291 km/s
(105,448 km/h)

and obviously its speed is different, from day to day, varying by about 19.697 km/hour from one day to the next (182 days x 19.697 increment per day = 3,585 km/hour in toto.

So the distance varies every day too and your guess that earth would be the same distance away in summer as in winter is wrong. What would be true for one day only, however, is that the autumn day about 2 weeks after the autumnal equinox and the spring day about 2 weeks after the spring equinox (the midpoints between aphelion and perihelion) would see the earth have similar distances and orbital speeds to one another. For one day only,

Answer 2

The earth has an elliptical orbit. The speed of the Earth is fastest when it's closest to the sun, in January (which is either winter or summer, depending on your hemisphere).

The relative motion of the sun seen from the earth is called analemma. The figure of 8 motion (take a photo of the sun on the 1st day of every month from the same place and the same direction to see this) is caused by the earth's eliptical orbit.

There is a really good explanation in source 1 below, and a neat composite photo is source 2.

Answer 3

Yes, Earth's speed varies from 29.29 km/s at aphelion to 30.29 km/s at perihelion. But northern hemisphere winter occurs at perihelion, not aphelion. That is because then seasons are not caused by the changing distance to the Sun, the difference is too small. The seasons are caused by the changing angle at which the Sun's rays hit Earth due to the Earth's axis being tilted 23 degrees to the plane of its orbit. This also explains how it can be winter in Europe on the same day that it is summer in Australia.

Answer 4

Wrong! When it is summer in the Northern hemisphere, it is winter in the Southern, and vice versa. The Earth's orbit is nearly circular, with only a slight degree of eccentricity to it. Because the Earth is tilted on its axis at an angle of 23 and a 1/2 degrees, when the North Pole is in line with the sun, it is summer up North, and the sun never sets, North of the Arctic circle then, while it is perpetually dark at the Southern polar regions, but when it's the South Pole (December - February), it's summer in the Southern hemisphere. Earth's speed in its orbit is at a maximum when it is closest to the sun.

Answer 5

. It is closer during the northern winter, so it moves faster around the sun. During the northern summer it is farther away from the sun so it is slower.

In an elliptic circle the orbiting body has to cover the same area of the circle for the same periood of time. That is why faster when closer. Area defined by a triangle drawn from two places in the orbit.

Answer 6

Wrong.
During January (to avoid confusion) Earth is closer to the Sun and has to move faster. In July, is in the aphelion and moves slower. Consider that the Sun is placed in one of the foci of the ellipse, so distances are necessarily different.

Answer 7

The earth is further away in the summer of the northern hemisphere, and so that means that it is moving more slowly.

HTH

Charles

Answer 8

the earth moves faster when it is closer to the sun, slower when it is further away. the tilt of the earth does not affect this in any form. an ellipse (unless its a circular ellipse) is not a perfect circle, so obviously if the earth is closer to the sun on one side it can't be the same distance away on the other side.

Answer 9

SURE