Long, dark 'streaks' spotted on Mars aren't what scientists thought
Mysterious dark streaks flowing across Mars's surface may not be the result of running water after all, a new artificial intelligence (AI) analysis suggests.
The streaks, first observed running along Mars's cliffsides and crater walls by NASA's Viking mission in 1976, were long thought by scientists to have formed as a result of the flow of ancient water across the now mostly desiccated planet's surface.
But an AI algorithm trained on slope streak observations has revealed a different origin for the streaks — likely being formed from wind and dust, not water. The findings, published May 19 in the journal Nature Communications, could have important implications for where humans choose to explore Mars, and the places they search for evidence of possible ancient life.
"That's the advantage of this big data approach," study co-author Adomas Valantinas, a planetary scientist at Brown University, said in a statement. "It helps us to rule out some hypotheses from orbit before we send spacecraft to explore."
The sinewy lines are darker than the surrounding Martian ground and extend for hundreds of meters downhill. The shorter-lived of these features are called recurring slope lineae (RSL), and regularly spring up during Mars's warmer spells.
This led some planetary scientists to suggest that seasonal temperature fluctuations could be causing ice or frozen aquifers to melt, or humid air to condense, sending streams of salty water trickling down the planet's craters. If this were true, it would make these regions of particular interest to future Mars missions.
Related: Curiosity rover finds largest carbon chains on Mars from 3.7 billion-year-old rock
To investigate this, the scientists behind the study trained a machine learning algorithm on confirmed streak sightings before making it scan through 86,000 satellite images to create a map of 500,000 streak features.
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"Once we had this global map, we could compare it to databases and catalogs of other things like temperature, wind speed, hydration, rock slide activity and other factors." Bickel said. "Then we could look for correlations over hundreds of thousands of cases to better understand the conditions under which these features form."
Using the map, the scientists found the streaks were most likely to form in places where wind speed and dust deposition was high, suggesting that they came from layers of fine dust sliding off steep slopes.
Other studies have pointed to tantalizing evidence of water and even life on Mars. If the study findings hold up, they could serve as a guide to sift between the Red Planet's useful leads and its red herrings.
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Yahoo
34 minutes ago
- Yahoo
The iPhone 17 Pro Max could have the biggest battery of any iPhone ever
When you buy through links on our articles, Future and its syndication partners may earn a commission. We're about two months away from the rumoured launch of the iPhone 17. And the leaks continue to come thick and fast. The latest says that we could see the biggest-capacity battery of any iPhone yet – a whopping 5000mAh for the iPhone 17 Pro Max. This capacity is very common with Android phones, but it's unchartered territory for an Apple handset. Will it actually mean a longer battery life though? Or just mitigate against the phone's greater energy needs? The iPhone 17 launch is expected in September. Four models are rumoured: the standard, Pro, Pro Max and new Air variant that's rumoured to be super slim. The Air is rumoured to have a single rear camera like the iPhone 16e, and a small battery. We're expecting 120Hz displays across the whole range. Wondering what else to expect? Read on, and we'll help you figure out if it's worth upgrading this year. iPhone 16e vs iPhone 16: which should you buy? The iPhone 16e's downgrades are in all the right places if movies on the move are your priority iPad Air M3 vs iPad Pro M4: what's the difference? Apple is yet to breathe a word about the iPhone 17, but we can be pretty confident of when it will launch: September 2025. Every iPhone in recent memory has launched in September (apart from the 12, which was delayed due to the pandemic). Behold. iPhone 11: 10th September 2019 iPhone 12: 13th October 2020 iPhone 13: 14th September 2021 iPhone 14: 7th September 2022 iPhone 15: 12th September 2023 iPhone 16: 9th September 2024 When exactly in September is harder to pin down. Apple usually launches its iPhones on a Tuesday, but the iPhone 16 was the first to be announced on a Monday (and the iPhone 16e launched on a Wednesday). It's far too early to say with any certainty when exactly the iPhone 17 will launch, but we'll bring you all the leaks and rumours closer to September. This could be the last year with the current iPhone launch schedule. One recent report says that Apple might split future iPhone launches across two separate release windows – retaining the traditional autumn schedule for Pro models while shifting standard models to the following spring. This would take effect from 2026, possibly the same year that the foldable iPhone launches (here's everything we know so far about Apple's folding iPhone). The nature of inflation means that devices like phones usually get more expensive. But in the last couple of years, we've seen much more modest price rises than previously. In some cases, prices have remained the same, or even fallen, meaning a new model launches for less than its inferior predecessor. The iPhone 16 range costs broadly the same as the iPhone 15 before it. iPhone 16 iPhone 16 Plus iPhone 16 Pro iPhone 16 Pro Max 128GB £799 / $799 / AU$1399 £899 / $899 / AU$1599 £999 / $999 / AU$1799 N/A 256GB £899 / $899 / AU$1599 £999 / $999 / AU$1799 £1099 / $1099 / AU$1999 £1199 / $1199 / AU$2149 512GB £1099 / $1099 / AU$1949 £1199 / $1199 / AU$2149 £1299 / $1299 / AU$2349 £1399 / $1399 / AU$2499 1TB N/A N/A £1499 / $1499 / AU$2699 £1599 / $1599 / AU$2849 For context, Apple's latest iPad Pro launched at £50 / $200 / AU$200 more than the model it replaces, though admittedly it did add an OLED screen to the offering. But the AirPods 4 with Active Noise Cancellation launched at the same price as the AirPods 3, and that's despite adding ANC. So Apple's prices don't always go up. Running counter to that, the iPhone 16e replaced the iPhone SE as Apple's cheapest iPhone. But with a starting price of £599 / $599 / AU$999, it's not exactly budget. Which suggests Apple has given up on the cheap phone market. Prices are notoriously tricky to predict, especially this far in advance – and especially for a new variant like the iPhone 17 Air. The recent tariff uncertainty has prompted some Apple analysts to forecast a price rise, but with tariffs changing by the day, it's too early to make any predictions. Smartphones were supposed to be among the devices exempt from tariffs, but then President Trump backtracked and threatened tariffs of "at least" 25 per cent on any iPhone made outside America. According to Counterpoint Research, this will spell a price rise. More RAM has been rumoured for the iPhone 17 range (more on this later), but with 12GB RAM modules costing 50 per cent more than 8GB ones, a price rise could be on the cards. We'll bring you more price leaks and rumours nearer to launch. One of the biggest rumours concerning the iPhone 17 is the range make-up. Before the iPhone 16 even launched, there was talk of the Plus model being replaced by a new 'Air' or 'Slim' variant. As the name suggests, this would be slimmer than the current Plus, but also have other points of difference, like a different screen size and camera arrangement. According to analyst Ming-Chi Kuo (who has a decent track record when it comes to these things), the iPhone 17 Air will measure just 5.5mm at its thinnest point, approaching the svelte dimensions of Apple's 5.1mm iPad Pro M4. This remarkable thinness isn't merely an engineering achievement – Bloomberg's Mark Gurman suggests it could serve as a crucial testing ground for technologies destined for future foldable Apple devices. Here's how it might look, with a render created by Front Page Tech. The pursuit of such a slim profile has led Apple to make several significant design decisions, Gurman says: the frame will use a unique titanium-aluminium blend, with a higher proportion of aluminium than seen in current Pro models. Physical SIM functionality will be replaced entirely by eSIM technology, while audio output will rely on a single speaker at the top rather than the dual-speaker configuration found in current iPhones. If this is true, it could impact sound quality, so consider our interest piqued. One more design compromise – the USB-C port on the bottom might not be centred, but rather be situated closer to the rear of the device than the front. That's in order to accommodate display components within the enclosure, according to a dummy model seen by AppleTrack. That's a fairly minor change in the grand scheme of things. But unsightly to those with an eye for design, as it would mess up the pleasing symmetry of the device's bottom edge. We can't imagine Steve Jobs ever countenancing it. In leaker Majin Bu's photos (via GSMArena) of a dummy iPhone 17 Air, the handset certainly looks slim, but the camera lens juts out quite a bit from the top half. Which could turn some people off. The iPhone 17 Air also thought to feature a black camera bar across the width of its back panel. And speaking on the Recycle Bin podcast, tipster Jon Prosser speculated that the iPhone 17 Air could have a 6.7-inch screen – bigger than the 6.55 inches previously rumoured (though this was rounded up to 6.6 inches). 6.7 inches would be the same size as the screen on the iPhone 16 Plus – which would make sense, seeing as the 17 Air is said to replace the 16 Plus in Apple's line-up. Apple is said to be using high-density battery cells in the iPhone 17 Air in order to cram more battery power into a slimmer frame. That's according to Ming-Chi Kuo. There's talk of Apple increasing the screen size of the standard iPhone model to bring it in line with the Pro. Currently, the iPhone 16 has a 6.1-inch screen, compared to the iPhone 16 Pro's 6.3-incher. With the rumoured iPhone 17 Air replacing the Plus model, that would leave the iPhone 17 range as follows: iPhone 17: 6.3 inches iPhone 17 Air/Slim: 6.6/6.7 inches iPhone 17 Pro: 6.3 inches iPhone 17 Pro Max: 6.9 inches But that's not the only screen change being mooted. Apple is also said to bring 120Hz refresh rates to every iPhone in the line-up (including the rumoured iPhone 17 Air). This is a pretty big deal, given that its so-called ProMotion displays are currently exclusive to the Pro models. But according to display analyst Ross Young (via MacRumors), 120Hz will soon be standard across the board. This was also mooted by a leaker on Weibo(via MacRumors) who said this would be enabled by Samsung's M14 OLED display panel (which is currently only used in Apple's iPhone 16 Pro and Pro Max). Not only would 120Hz refresh rates mean better handling of more frantic action, with less slowdown, it would also allow every iPhone 17 model to scale down to the more power efficient refresh rate of just 1Hz, extending battery life while also allowing for always-on displays to show information while the handset is locked (again, this feature is currently limited to the Pro models). Samsung's M14 panel is also 30 per cent brighter than the M13 that came before it. However, one leaker has poured cold water on our expectations. Someone calling themselves Digital Chat Station posted on Weibo that you should "lower your expectations appropriately", which suggests that either the standard and Air will only have 90Hz screens (still up from the 60Hz of the standard iPhone 16) or that they will have 120Hz displays but that these will lack the energy-efficient ProMotion tech of the Pro models. That would mean fewer gains in battery life. But another screen technology could help out in this area. Low-Dielectric TEE (Transmission Electrically Enhanced) apparently "improves battery efficiency, maximises display durability, and enhances overall performance compared to existing display technologies" according to the person who posted about it. It's said to be new technology about very little is known, so file this under 'maybe' for now. The iPhone 17 is also said to have an anti-reflective screen that's more scratch-resistant than Apple's current Ceramic Shield, according to a rumour on Chinese social network Weibo. A smaller Dynamic Island could also be in store. Analyst Jeff Pu says (via MacRumors) that the iPhone 17 Pro Max will have a "much narrowed [sic] Dynamic Island" thanks to the Face ID system using a smaller "metalens". Instead of being curved like a traditional lens, this would be thin and flat and be able to focus light more precisely. It would be the first change to the Dynamic Island since it was introduced in 2022. However, another well-respected analyst thinks the Dynamic Island will remain "largely unchanged". The iPhone 17 is said to feature some significant design changes compared to its predecessor. One of the biggest – and most puzzling – design changes mentioned is ditching the Pro models' titanium build in favour of aluminium across the board. That's according to The Information, which notes that "the back of the Pro and Pro Max models will feature a new part-aluminium, part-glass design. "The top of the back will comprise a larger rectangular camera bump made of aluminium rather than traditional 3D glass. The bottom half will remain glass to accommodate wireless charging." Why is this puzzling? Apple only introduced titanium in 2023, on the iPhone 15 Pro and Pro Max. Apple marketed titanium as strong yet light, and a more premium option than the stainless steel previously used. (It hasn't used aluminium for a premium iPhone since the iPhone X in 2017.) As such, this rumour has been met with some skepticism. The iPhone 17 Pro could have the same horizontal camera bar on the rear as the iPhone 17 Air, according to this render from Front Page Tech. But another leak contradicts that, showing the camera bar split into two distinct sections. Mark Gurman reckons the bar will be the same colour as the rest of the iPhone too, whereas previously it was thought to be a different shade in order to stand out. According to leaker Majin Bu, the camera bar will mean the Apple logo sits lower on the back of the iPhone 17 Pro model than on the iPhone 16 range. The iPhone 17's battery could be easier to remove, thanks to a different type of adhesive. According to MacRumors, that would make the batteries easier to swap, extending the life of your iPhone. According to these CADs (computer-aided designs) shared by reputable leaker Sonny Dickson, the iPhone 17 will have a very similar design to the iPhone 16, with only the Air, Pro and Pro Max getting the horizontal camera bar. Though the standard iPhone 17 model would still get plenty of other improvements, like the 120Hz always-on screen and possibly some new colour schemes. The iPhone 17 Air will have the same dimensions as the iPhone 17 Pro Max, apart from being slimmer, according to leaker Ice Universe. "The iPhone 17 Air is 5.5mm thick, while the iPhone 17 Pro Max is 8.725mm thick," they wrote on Weibo. That would make the 17 Pro Max quite a bit thicker than the 16 Pro Max. Apple usually gives its new iPhones a new processor, and the iPhone 17 should be no different. The range-topping iPhone 17 Pro and Pro Max are expected to feature Apple's A19 Pro chip, while the iPhone 17 and 17 Air/Slim are thought to feature the standard A19. This is in keeping with the iPhone 16 range, which was the first to feature different versions of the same chip in the Pro and non-Pro models. TSMC's upcoming N3P technology is thought to feature. This is said to offer better efficiency and increased transistor density. More RAM is also thought to be in the offing. Analyst Jeff Pu has previously said that the Pro models will have 12GB RAM, and the non-Pros 8GB. However, analyst Ming-Chi Kuo reckons that only the Pro Max will have 12GB, with the rest featuring 8GB. In a more recent blog post, he expanded this prediction to include the iPhone 17 Air as well. Apple doesn't reveal how much RAM each iPhone features, so it's down to teardowns and online sleuths to reveal it. The iPhone 17 Air, in particular, is expected to feature at least 8GB of RAM to support Apple Intelligence's AI features, despite its slim profile. However, the thin design necessitates some compromises – notably, the device will completely eliminate the physical SIM tray in favour of eSIM technology, which could affect its availability in certain markets. Other new features are said to include an Apple-designed 5G modem (only in the Slim/Air variant), and an Apple custom Wi-Fi 7 chip. The iPhone 17 range is also expected to gain vapour chamber cooling (via 9to5Mac). This is a more effective method of passive cooling to squeeze the maximum possible performance out of the phone. Opinion is split whether this will be exclusive to the Pro Max, or available on all models. The iPhone 17 Pro Max is also said to have a 5000mAh battery – larger than any iPhone that has come before it. The 16 Pro Max has a 4685mAh battery. Google's Gemini AI assistant could arrive as part of the iPhone 17. Google's CEO Sundar Pichai has reportedly been talking to his Apple counterpart Tim Cook about having Gemini built into the next iPhone, and hopes to have a deal in place by September, Bloomberg reports. But Apple's own Siri AI has reportedly been shunted back to 2026, according to Bloomberg. We could see faster charging speeds. 91Mobiles spotted that Apple has submitted regulatory filings in Taiwan for two new MagSafe chargers supporting the Qi 2.2 standard. This would step up the maximum charging speed from 25W to 50W, meaning greater efficiency and less heat generation, and even better alignment when snapped into place using their magnets. Wins all round. The camera is always one of the main selling points of any iPhone, and the iPhone 17's could be the best yet, with a comprehensive update across the range expected. The top-end iPhone 17 Pro Max is rumoured to be the first iPhone with three 48-megapixel rear cameras: wide, ultrawide and tetraprism telephoto. The iPhone 17 Air, given its svelte nature, is expected to have just a single rear camera, to allow it to be much thinner than its stablemates. One model in the range is also said to have a mechanical aperture, to vary the amount of light allowed in to the sensor. This would allow for shallow depth of field shots, and make it a much more versatile camera. However, The Information doesn't reveal which model this would be, though it would make sense to be the 17 Pro Max, with the highest-end model getting the most advanced features. The 5x telephoto zoom lens is thought to remain exclusive to the Pro models in the iPhone 17 range. Every phone in the family is said to have a 24-megapixel front-facing camera – double the resolution of the iPhone 16's 12-megapixel selfie-taker. The iPhone 17 is also rumoured to gain 8K video recording, according to a source on Weibo (via GSMArena). Some Android phones allow 8K video recording, but this would be the first iPhone with the feature. Even before the iPhone 16 broke cover, the 17 was said to be the first significant upgrade to the iPhone in years. If these rumours are true, that definitely looks to be the case. As ever, Apple won't be short of competition, with Google, Samsung and a host of Chinese competitors vying for your hard-earned. And who knows what the economic climate will be come September, with price rises potentially on the cards. As such, Apple will have to deliver even more from the iPhone 17. We'll keep updating this page regularly with all the latest leaks, rumours and news, so make sure you check back for the latest. MORE: Browse today's best Apple deals: iPhone, iPad, HomePod These are the best smartphones for music and movies Google fans, check out the best Android phones
New York Post
an hour ago
- New York Post
Shop the world's first AI-powered robotic pool cleaner on sale for Prime Day
New York Post may receive revenue from affiliate and advertising partnerships for sharing this content and/or when you make a purchase. Let's face it — cleaning the pool is the least fun part of pool ownership. The sun's shining, your floatie is calling, but instead, you're stuck dragging hoses and skimming leaves like it's 1997. Enter Beatbot: the pool-cleaning robot that actually gets it. And, with Amazon Prime Day here, the timing couldn't be better. Whether your pool's your summer sanctuary or just the neighborhood hangout, the right pool vacuum can totally change the game, and there are some seriously good deals on the table. This year, three Beatbot models are stealing the spotlight: the AquaSense 2 Ultra, AquaSense 2 Pro and the OG AquaSense 2. The Ultra is basically the Tesla of pool vacuums: fast, sleek and smart enough to make you feel like your pool's cleaning itself (because it is). The Pro is no slouch either, packing premium features without the Ultra price tag. And, the original AquaSense 2? Still a fan favorite, still a beast and now more affordable than ever. Here's the thing: Beatbot is all about reclaiming your time. These vacuums are cordless, quiet and weirdly satisfying to watch as they zip around the deep end like tiny aquatic Roombas. No more wrestling with hoses or mystery gunk in the filter basket; simply press a button and go enjoy your margarita. That's the energy we're bringing into this summer. And look, we get it — there are a ton of gadgets on sale for Prime Day. But Beatbot deals this good don't come around often. If you've been eyeing one of these bots but couldn't justify the splurge, this is your shot. Summer's short. Don't waste another minute manually cleaning your pool like it's a punishment. Amazon If you've ever wrestled with a clunky pool vacuum, chased floating leaves with a net or spent your Saturday elbows-deep scrubbing tiles instead of sipping something cold by the water — pause everything. The Beatbot AquaSense 2 Ultra has arrived, and it's the poolside game-changer you didn't know you were waiting for. Picture this: a sleek, cordless robot that thinks for itself. With HybridSense AI, it scans your pool like it's memorizing a map for a heist — camera, ultrasonic and infrared sensors all working in harmony to tackle every inch of gunk and grime. The floor, the walls, the waterline, even the surface? Handled. Oh, it clarifies your water too, because cloudy pool water is so last summer. The AquaSense 2 Ultra is a full-on pool whisperer. It adapts in real time to your pool's unique curves and quirks, dodging obstacles and switching tactics like it was trained by NASA. So, you can say goodbye to leaves floating on the surface and debris stuck in that awkward corner step. While it's making your pool look like a resort, you're not lifting a finger. You can call it back to the edge on the water surface, too. It even parks itself at the surface when it's done, like the tidy little overachiever it is. Amazon Meet your new pool party MVP: the Beatbot AquaSense 2 Pro. This little champ is a 5-in-1 superstar that scoops leaves off the surface, scrubs those tricky waterlines and walls, cleans the pool floor and even gives your water a sparkling glow. What's more, the AquaSense 2 Pro is packed with brainy features like the ClearWater Natural Clarification System, which keeps your water crystal clear and swimmer-friendly without any harsh chemicals. It's also clad with Smart Water Surface Parking, so it knows just where to chill when it's taking a break, and with a quick tap on the app, you can send it on its merry way or call it back like a loyal pool pup. Thanks to 22 sensors, this robot maps out every nook and cranny of your pool, making sure no dirt or grime crashes your swim vibes. Ready for the best part? This little hero can clean nonstop for up to 11 hours; that's practically a full day of pool party prep without you lifting a finger. So, it's time to dive in, relax and let this bot do the dirty work! Amazon The Beatbot AquaSense 2 Pool Robot Vacuum is redefining what it means to keep your pool impeccably clean with minimal effort. Thanks to its advanced navigation system and 16 smart sensors, this robot takes the guesswork out of pool maintenance, mapping out every inch of your pool's floors, walls and waterlines for truly comprehensive cleaning. Its tough automotive-grade IMR coating is durable, and it'll make you think, 'Thank goodness I picked one up on sale.' Battery life is where the AquaSense 2 really shines, delivering up to four hours of continuous cleaning powered by a hefty 10,000mAh battery. But what really sets it apart is the dual-pass waterline scrubbing feature, tackling that notoriously tricky waterline grime with precision and intensity. This focused approach means your pool stays sparkling longer, sparing you from constant upkeep. Plus, with a generous three-year warranty that includes full machine replacement, you're not just investing in a cleaner pool — you're investing in peace of mind. Better yet, its wireless charging removes the hassle of cords, while the smart water surface parking and one-click app retrieval let you summon the cleaner back with ease. This robot fits seamlessly into a modern lifestyle, turning pool maintenance from a dreaded chore into a smart, automated ritual. If you're after a pool cleaning solution that's as savvy as it is efficient, the AquaSense 2 is undoubtedly worth the attention. Beatbot's Trade-In Program What's great about Beatbot is its Trade-In Program. Simply trade in your old pool cleaner and get up to a $200 credit to go toward a newly minted one. Yes, please. Your Prime Day FAQs, answered How long does Prime Day last? In a new twist for 2025, shoppers have 4 days to take advantage of Prime Day discounts. This sale starts on July 8 at 12:01 a.m. PT and runs through July 11 at 11:59 p.m. PT. When does Prime Day end? Prime Day 2025 ends on July 11 at 11:59 p.m. PT, so east-coasters have until about 3 a.m. on July 12 their time to shop the deals. Do you have to have Amazon Prime to shop Prime Day? Prime Day is a member-exclusive sale event. Interested shoppers can grab a 30-day free trial to try Prime, and its many benefits, with no strings attached. What are the best Prime Day deals? From reporting on Amazon sales throughout the years, we can tell you for certain that it's the ideal period to stock up on household essentials, score great deals on vacuums, tech and appliances, refill your skincare empties, and comb through the massive catalog of Amazon best-sellers. Is Prime Day worth it? We certainly think so! Prime Day is a great chance to score Black Friday-worthy discounts on thousands of deals, including everything from big ticket items to Post reader-favorite trash bags. Our team diligently sorts through all the offers to find you the very best items to grab on sale. When is the next Prime Day? Already wondering when the next Amazon Prime Day is? Prime Day takes place in July each year, so it's safe to assume it will take place in mid-July 2026 — similar to previous years. Can't wait to shop more Amazon deals? Look out for Amazon's Prime Big Deal Days sale, which typically runs in October for shoppers looking to beat the holiday rush of Black Friday. Don't miss Post Wanted's around-the-clock coverage. Click here to find all of the best deals. For over 200 years, the New York Post has been America's go-to source for bold news, engaging stories, in-depth reporting, and now, insightful shopping guidance. We're not just thorough reporters – we sift through mountains of information, test and compare products, and consult experts on any topics we aren't already schooled specialists in to deliver useful, realistic product recommendations based on our extensive and hands-on analysis. Here at The Post, we're known for being brutally honest – we clearly label partnership content, and whether we receive anything from affiliate links, so you always know where we stand. We routinely update content to reflect current research and expert advice, provide context (and wit) and ensure our links work. Please note that deals can expire, and all prices are subject to change.
CNN
2 hours ago
- CNN
Earth is as far away from the sun as it ever gets. So why is it so hot?
The peak of summer is approaching for those of us in the Northern Hemisphere, but as we prepare for more sunshine and sweltering temperatures, our planet is spinning at its farthest point from the sun. On Thursday at 3:55 p.m. ET, our planet reached what's called the aphelion — the most distant point in its orbit around the sun, roughly 3 million miles farther away than when it's closest. This happens every year in early July, which might sound backward. If we're farthest from the sun, shouldn't it be cooler? People tend to associate proximity with warmth, so it seems natural to assume the seasons are caused by changes in how far Earth is from the sun. But the planet's distance has little to do with it. The real reason for seasonal temperature changes lies in the fact that Earth is tilted. Our planet spins at an angle — about 23.5 degrees — which means different parts of the globe receive more (or less) sunlight depending on the time of year. In July, the Northern Hemisphere is tilted toward the sun, bringing longer days and higher sun angles that lead to more direct sunlight — all of which produce summer-like heat. In contrast, the shape of Earth's orbit plays only a minor role. Although it's slightly oval-shaped rather than perfectly circular, the difference between our closest and farthest points from the sun is relatively small. Right now, Earth is about 3.1 million miles farther from the sun than it is in early January when it reaches perihelion, its closest point. Compared to its average distance of 93 million miles, that's only about a 3.3% difference. Because sunlight spreads out as it travels, even a relatively small change in distance results in about a 7% drop in the amount of solar energy reaching the planet. That's tiny compared to the effect of Earth's tilt. Just how big is the difference? Let's look at a few examples. In cities like Houston, New Orleans and Phoenix — near 30 degrees north in latitude — the amount of solar energy reaching Earth's atmosphere in summer is more than double what those cities receive in winter. Farther north, around 40 degrees, the seasonal swing is even more dramatic. Cities like New York, Denver and Columbus see solar energy climb from about 145 watts per square meter in winter to 430 in summer — nearly a 300% difference. So, while it's true that Earth is receiving less energy from the sun right now, that detail barely registers compared to the power of the planet's tilt. A slight angle in Earth's spin does far more to shape our seasonal patterns than a few million miles of extra distance ever could. In the end, it's not how close we are to the sun that makes summer feel like summer — it's how we're angled toward it.
