Remember to wish your friends and family, "Happy Aphelion Day!" Thursday marks the point in Earth's orbit it is the farthest away from the Sun.
This orbital milestone is known as aphelion. On Earth, aphelion happens in early July, about two weeks after the summer solstice. Earth will be in aphelion at 4:06 p.m. EDT on Thursday. At this time, Earth will be 94,506,364 miles from the Sun, according to Timeanddate.com.
Next year, aphelion happens on July 5.
The opposite of aphelion is known as perihelion when the Earth is closest in its orbit to the Sun, which fell on Jan. 4 this year when Earth was 91,403,034 miles from the Sun.
NASA Ambassador Tony Rice explains that Earth's distance from the Sun does not fully dictate our seasons. Earth does not orbit the sun in a perfect circle, and the Earth itself is also not a perfectly round globe.
"It doesn't make a whole lot of sense in July, but actually, that's not where those hot temperatures come from. Our seasons come from the axial tilt of the Earth," Rice said.
Earth spins on its axis and orbits the Sun in an elongated circle orbit.
As the Earth spins on its axis, producing night and day, it also moves about the Sun in an elliptical (elongated circle) orbit that requires about 365.25 days to complete. The Earth's spin axis is tilted with respect to its orbital plane. This is what causes the seasons. When the Earth's axis points towards the Sun, it is summer for that hemisphere.
During the summer in the Northern Hemisphere, Earth's axis is pointing toward the Sun, creating the warmth we feel this time of year.
"You've also got to consider that there is so much more landmass in the Northern Hemisphere, and that landmass heats up really, really easy compared to the ocean," Rice said.