Why can’t it always be summer? It’s all about the Earth’s tilt
Earth’s axial tilt causes the seasons. As Earth orbits the Sun, different hemispheres tilt toward or away, creating summer and winter depending on location.
Why can’t it always be summer? – Amanda, age 5, Chile
With its long days just itching to be spent by water doing nothing, summer really can be an enchanting season. As Jenny Han wrote in the young adult novel “The Summer I Turned Pretty”: “Everything good, everything magical happens between the months of June and August.”
But all good things must come to an end, and summer cannot last forever. There’s both a simple reason and a more complicated one. The simple reason is that it can’t always be summer because the Earth is tilted. The more complicated answer requires some geometry.
I’m a professor of geography and the environment who has studied seasonal changes on the landscape. Here’s what seasons have to do with our planet’s position as it moves through the solar system.
This animation shows why the Earth has seasons.
Closeness to the Sun doesn’t explain seasons
First, you need to know that the Earth is a sphere – technically, an oblatespheroid. That means Earth has a round shape a little wider than it is tall.
Every year, Earth travels in its orbit to make one revolution around the Sun. The Earth’s orbit is an ellipse, which is more like an oval than a circle. So there are times when Earth is closer to the Sun and times when it’s farther away.
A lot of people assume this distance is why we have seasons. But these people would be wrong. In the United States, the Earth is 3 million miles closer to the Sun during winter than in the summer.Our distance from the Sun is not why we have seasons. NASA
Spinning like a top
Now picture an imaginary line across Earth, right in the middle, at 0° latitude. This line is called the equator. If you drew it on a globe, the equator would pass through countries including Brazil, Kenya, Indonesia and Ecuador.
Everything north of the equator, including the United States, is considered the Northern Hemisphere, and everything south of the equator is the Southern Hemisphere.
Now think of the Earth’s axis as another imaginary line that runs vertically through the middle of the Earth, going from the North Pole to the South Pole.
As it orbits, or revolves, around the Sun, the Earth also rotates. That means it spins on its axis, like a top. The Earth takes one full year to revolve around the Sun and takes 24 hours, or one day, to do one full rotation on its axis.
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This axis is why we have day and night; during the day, we’re facing the Sun, and at night, we’re facing away.
But the Earth’s axis does not go directly up and down. Instead, its axis is always tilted at 23.5 degrees in the exact same direction, toward the North Star.
The Earth’s axis is tilted due to a giant object – perhaps an ancient planet – smashing into it billions of years ago. And it’s this tilt that causes seasons.Because of the tilt of the Earth, we are able to experience the seasons. Stephanie Spera
It’s all about the tilt
So that means in June, the Northern Hemisphere is tilted toward the Sun. That tilt means more sunlight, more solar energy, longer days – all the things that make summer, well, summer.
At the same time, the Southern Hemisphere is tilted away from the Sun. So countries such as Australia, Chile and Argentina are experiencing winter then.
To say it another way: As the Earth moves around the Sun throughout the year, the parts of the Earth getting the most sunlight are always changing.
Fast-forward to December, and Earth is on the exact opposite side of its orbit as where it was in June. It’s the Southern Hemisphere’s turn to be tilted toward the Sun, which means its summer happens in December, January and February.
If Earth were not tilted at all, there would be no seasons. If it were tilted more than it is, there would be even more extreme seasons and drastic swings in temperature. Summers would be hotter and winters would be colder.The Earth’s axis is always tilted at 23.5 degrees. Stephanie Spera
Defining summer
Talk to a meteorologist, climate scientist or author Jenny Han, and they’ll tell you that for those of us in the Northern Hemisphere, summer is June, July and August, the warmest months of the year.
But there’s another way to define summer. Talk to astronomers, and they’ll tell you the first day of summer is the summer solstice – the day of the year with the longest amount of daylight and shortest amount of darkness.
The summer solstice occurs every year sometime between June 20 and June 22. And every day after, until the winter solstice in December, the Northern Hemisphere receives a little less daylight.
Summer officially ends on the autumnal equinox, the fall day when everywhere on Earth has an equal amount of daylight and night. The autumnal equinox happens every year on either September 22 or 23.
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But whether you view summer like Jenny Han or like an astronomer, one thing is certain: Either way, summer must come to an end. But the season and the magic it brings with it will be back before you know it.
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Harkins Theatres Announces Rob Reiner Tribute Screening of The American President
Harkins Theatres has announced a special one-day tribute screening honoring acclaimed filmmaker Rob Reiner, celebrating his life’s work and cinematic legacy.
On December 17, select Harkins locations will screen Reiner’s 1995 political romance The American President, with all proceeds benefiting the Human Rights Campaign. Tickets are priced at $5, making the event both an accessible film experience and a charitable fundraiser.
The tribute was announced via Harkins’ official, verified social media accounts and is positioned as a legacy celebration, not a memorial.
🎥 Why The American President?
Released in 1995 and written by Aaron Sorkin, The American President stars Michael Douglas and Annette Bening and remains one of Rob Reiner’s most politically resonant films. The movie blends romance, idealism, and civic responsibility — themes that have consistently appeared throughout Reiner’s career.
The film later served as a creative blueprint for The West Wing, cementing its place in modern political storytelling.
Rob Reiner’s career spans more than five decades, including landmark films such as:
This Is Spinal Tap
Stand By Me
The Princess Bride
When Harry Met Sally…
Misery
A Few Good Men
His work is often praised for balancing entertainment, empathy, and social conscience, making tribute events like this especially meaningful to longtime audiences.
Hollywood Legend Rob Reiner and Wife Found Dead; Son in Custody
Renowned filmmaker Rob Reiner and his wife, Michele Singer Reiner, were found dead in their Los Angeles home in a reported homicide. Police have arrested their son in connection with the case, and tributes are pouring in.
Director Rob Reiner participates in a discussion following a screening of the film LBJ at the LBJ Presidential Library in Austin, Texas on Saturday October 22, 2016 On Saturday evening October 22, 2016, the LBJ Presidential Library held a sneak peek of Rob Reiner’s new filmÊLBJ, starring Woody Harrelson as the 36th president. The film, which premiered at the Toronto International Film Festival in September, chronicles the life and times of Lyndon Johnson who would inherit the presidency at one of the most fraught moments in American history. Following the screening, director Rob Reiner, actor Woody Harrelson, and writer Joey Hartstone joined LBJ Library Director Mark Updegrove on stage for a conversation about the film. LBJ Library photo by Jay Godwin 10/22/2016
Hollywood Legend Rob Reiner and Wife Found Dead; Son in Custody
December 15, 2025
Renowned filmmaker and actor Rob Reiner, 78, and his wife Michele Singer Reiner, 68, were found dead in their Brentwood, Los Angeles home on Sunday, authorities say. Emergency responders were called to the residence Sunday afternoon, where both were discovered with fatal wounds consistent with a stabbing. Police are treating the case as a double homicide.
Los Angeles police arrested the couple’s 32-year-old son, Nick Reiner, in connection with the deaths. He is being held in custody as investigators continue to piece together the circumstances surrounding the incident.
2016 SAMHSA Voice Awards
Reiner was one of Hollywood’s most influential figures, known for his work as a director, producer and actor. His career spanned decades, from early television fame to directing beloved films that shaped American cinema.
Friends, colleagues and public figures have begun sharing tributes and reactions to the news as the investigation is ongoing.
More details will be updated as they become available.
FDA’s COVID-19 Vaccine Safety Claims Lack Solid Evidence—Why Overreaction Could Harm Public Health
COVID-19 vaccine safety: The FDA’s claims about COVID-19 vaccine deaths in children lack strong evidence and could restrict vaccine access. Learn why experts say VAERS reports aren’t proof, and how overreacting may harm public health and trust in vaccines.
The death of children due to an unsafe vaccine is a serious allegation. I am a pediatric cardiologist who has studied the link between COVID-19 vaccines and heart-related side effects such as myocarditis in children. To my knowledge, studies to date have shown such side effects are rare, and severe outcomes even more so. However, I am open to new evidence that could change my mind. But without sufficient justification and solid evidence, restricting access to an approved vaccine and changing well-established procedures for testing vaccines would carry serious consequences. These moves would limit access for patients, create roadblocks for companies and worsen distrust in vaccines and public health. In my view, it’s important for people reading about these FDA actions to understand how the evidence on a vaccine’s safety is generally assessed.
Determining cause of death
The FDA memo claims that the deaths of these children were directly related to receiving a COVID-19 immunization. From my perspective as a clinician, it is awful that any child should die from a routine vaccination. However, health professionals like me owe it to the public to uphold the highest possible standards in investigating why these deaths occurred. If the FDA has evidence demonstrating something that national health agencies worldwide have missed – widespread child deaths due to myocarditis caused by the COVID-19 vaccine – I don’t doubt that even the most pro-vaccine physician will listen. So far, however, no such evidence has been presented. While a death logged in VAERS is a starting point, on its own it is insufficient to conclude whether a vaccine caused the death or other medical causes were to blame. To demonstrate a causal link, FDA staff and physicians must align the VAERS report with physicians’ assessments of the patient, as well as data from other sources for monitoring vaccine safety. These include PRISM, which logs insurance claims data, and the Vaccine Safety Datalink, which tracks safety signals in electronic medical records. It’s known that most deaths logged only in VAERS of children who recently received vaccines have been incorrectly attributed to the vaccines – either by accident or in some cases on purpose by anti-vaccine activists.
Heart-related side effects of COVID-19 vaccines
In his Substack and Twitter accounts, Prasad has said that he believes the rate of severe cardiac side effects after COVID-19 vaccination is severely underestimated and that the vaccines should be restricted far more than they currently are. In a July 2025 presentation, Prasad quoted a risk of 27 cases per million of myocarditis in young men who received the COVID-19 vaccine. A 2024 review suggested that number was a bit lower – about 20 cases out of 1 million people. But that same study found that unvaccinated people had greater risk of heart problems after a COVID-19 infection than vaccinated people. In a different study, people who got myocarditis after a COVID-19 vaccination developed fewer complications than people who got myocarditis after a COVID-19 infection. Existing vaccine safety infrastructure in the U.S. successfully identifies dangers posed by vaccines – and did so during the COVID-19 pandemic. Today, most COVID-19 vaccines in the U.S. rely on mRNA technology. But as vaccines were first emerging during the COVID-19 pandemic, two pharmaceutical companies, Janssen and AstraZeneca, rolled out a vaccine that used a different technology, called a viral vector. This type of vaccine had a very rare but genuine safety problem that was detected.A report in VAERS is at most a first step to determining whether a vaccine caused harm. VAERS, the Vaccine Safety Datalink, clinical investigators in the U.S. and their European counterparts detected that these vaccines did turn out to cause blood clotting. In April 2021, the FDA formally recommended pausing their use, and they were later pulled from the market. Death due to myocarditis from COVID-19 vaccination is exceedingly rare. Demonstrating that it occurred requires proof that the person had myocarditis, evidence that no other reasonable cause of death was present, and the absence of any additional cause of myocarditis. These factors cannot be determined from VAERS data, however – and to date, the FDA has presented no other relevant data.
A problematic vision for future vaccine approvals
Currently, vaccines are tested both by seeing how well they prevent disease and by how well they generate antibodies, which are the molecules that help your body fight viruses and bacteria. Some vaccines, such as the COVID-19 vaccine and the influenza vaccine, need to be updated based on new strains. The FDA generally approves these updates based on how well the new versions generate antibodies. Since the previous generation of vaccines was already shown to prevent infection, if the new version can generate antibodies like the previous one, researchers assume its ability to prevent infection is comparable too. Later studies can then test how well the vaccines prevent severe disease and hospitalization. The FDA memo says this approach is insufficient and instead argues for replacing such studies with many more placebo-controlled trials – not just for COVID-19 vaccines but also for widely used influenza and pneumonia vaccines. That may seem reasonable theoretically. In practice, however, it is not realistic. Today’s influenza vaccines must be changed every season to reflect mutations to the virus. If the FDA were to require new placebo-controlled trials every year, the vaccine being tested would become obsolete by the time it is approved. This would be a massive waste of time and resources.Influenza vaccines must be updated for every flu season.Jacob Wackerhausen/iStock via Getty Images Plus Also, detecting vaccine-related myocarditis at the low rate at which it occurs would have required clinical trials many times larger than the ones that were done to approve COVID-19 mRNA vaccines. This would have cost at least millions of dollars more, and the delay in rolling out vaccines would have also cost lives. Placebo-controlled trials would require comparing people who receive the updated vaccine with people who remain unvaccinated. When an older version of the vaccine is already available, this means purposefully asking people to forgo that vaccine and risk infection for the sake of the trial, a practice that is widely considered unethical. Current scientific practice is that only a brand-new vaccine may be compared against placebo. While suspected vaccine deaths should absolutely be investigated, stopping a vaccine for insufficient reasons can lead to a significant drop in public confidence. That’s why it’s essential to thoroughly and transparently investigate any claims that a vaccine causes harm.
