First day of summer, longest day of year falls on Friday

Summer fans, rejoice: The season officially begins Friday.

The summer solstice, which falls on June 21, marks the astronomical start of summer for the Northern Hemisphere. At 11:54 a.m. ET | 8:54 a.m. PT, the sun's most direct rays will reach the Tropic of Cancer, a line that marks the northernmost point they reach, according to AccuWeather.

SEE ALSO: Norwegian island wants to go 'time-free' when sun doesn't set

On the solstice, the sun rises between the pillars of Stonehenge in England and sets between the Pyramids of Giza in Egypt, AccuWeather reports.

The meteorological start of summer was on June 1.

Jupiter, the Milky Way and other things to see in the sky in June 2019

The astronomical first day of summer coincides with other occasions. World Music Day, or "Fete de la Musique," is an international celebration of music that was started in the 1980s in France.

The Alzheimer's Association marks the day with their "The Longest Day" initiative, which includes walks and runs to raise awareness.

It's also the International Day of Yoga, an official holiday of the United Nations.

SUMMER FUN AND ACTIVITIES

Dairy Queen offering free ice cream to start off summer

Need a summer job? Reynolds Wrap will pay you to travel US, eat free barbecue!

Summer movie preview: 'Toy Story,' 'Aladdin,' 'Lion King,' among movies with familiar characters returning to theaters

Study: Cruises better than other vacations for your well-being

Hawaii's Kailua Beach Park tops 2019 list of America's best beaches

BEATING THE HEAT

Tips to stay safe during the hot summer months

Heat stroke vs heat exhaustion: What's the difference and what are the symptoms?

Lotion in the refrigerator and more hacks to keep cool without AC

Tips for staying safe during a heat wave as the temperature rises

What is a heat wave? How heat waves form and temperatures climb

Why it's harder to cool off in humidity

How hot summer weather affects your car

MORE SUMMER HEALTH AND SAFETY

Natural remedies for sunburn

5 Facts About Sunscreen You Probably Didn't Know

Study finds summer can lead to weight gain in children

Summer 2019: What barbecue favorites are putting your health at risk?

Water bottle warning: Can you start a fire if you leave bottled water in your car?

Rip currents: Safety tips and what to know

What is a flash rip? And more facts to know about rip currents

SUMMER SCIENCE AND FUN FACTS

What does 'dog days of summer' really mean?

The reason fireflies light up will surprise you

We baked cookies inside a parked car just to prove how hot the inside of a car really is

Heat hypothesis: The link between summer weather and aggressive behavior