Tech
A US startup plans to deliver ‘sunlight on demand’ after dark. Can it work? Would we want it to?
A proposed constellation of satellites has astronomers very worried. Unlike satellites that reflect sunlight and produce light pollution as an unfortunate byproduct, the ones by US startup Reflect Orbital would produce light pollution by design.
The company promises to produce “sunlight on demand” with mirrors that beam sunlight down to Earth so solar farms can operate after sunset.
It plans to start with an 18-meter test satellite named Earendil-1 which the company has applied to launch in 2026. It would eventually be followed by about 4,000 satellites in orbit by 2030, according to the latest reports.
So how bad would the light pollution be? And perhaps more importantly, can Reflect Orbital’s satellites even work as advertised?
Bouncing sunlight
In the same way you can bounce sunlight off a watch face to produce a spot of light, Reflect Orbital’s satellites would use mirrors to beam light onto a patch of Earth.
But the scale involved is vastly different. Reflect Orbital’s satellites would orbit about 625km above the ground, and would eventually have mirrors 54 meters across.
When you bounce light off your watch onto a nearby wall, the spot of light can be very bright. But if you bounce it onto a distant wall, the spot becomes larger—and dimmer.
This is because the sun is not a point of light, but spans half a degree in angle in the sky. This means that at large distances, a beam of sunlight reflected off a flat mirror spreads out with an angle of half a degree.
What does that mean in practice? Let’s take a satellite reflecting sunlight over a distance of roughly 800km—because a 625km-high satellite won’t always be directly overhead, but beaming the sunlight at an angle. The illuminated patch of ground would be at least 7km across.
Even a curved mirror or a lens can’t focus the sunlight into a tighter spot due to the distance and the half-degree angle of the sun in the sky.
Would this reflected sunlight be bright or dim? Well, for a single 54 meter satellite it will be 15,000 times fainter than the midday sun, but this is still far brighter than the full moon.
The balloon test
Last year, Reflect Orbital’s founder Ben Nowack posted a short video which summarized a test with the “last thing to build before moving into space”. It was a reflector carried on a hot air balloon.
In the test, a flat, square mirror roughly 2.5 meters across directs a beam of light down to solar panels and sensors. In one instance the team measures 516 watts of light per square meter while the balloon is at a distance of 242 meters.
For comparison, the midday sun produces roughly 1,000 watts per square meter. So 516 watts per square meter is about half of that, which is enough to be useful.
However, let’s scale the balloon test to space. As we noted earlier, if the satellites were 800km from the area of interest, the reflector would need to be 6.5km by 6.5km—42 square kilometers. It’s not practical to build such a giant reflector, so the balloon test has some limitations.
So what is Reflect Orbital planning to do?
Reflect Orbital’s plan is “simple satellites in the right constellation shining on existing solar farms”. And their goal is only 200 watts per square meter—20% of the midday sun.
Can smaller satellites deliver? If a single 54 meter satellite is 15,000 times fainter than the midday sun, you would need 3,000 of them to achieve 20% of the midday sun. That’s a lot of satellites to illuminate one region.
Another issue: satellites at a 625km altitude move at 7.5 kilometers per second. So a satellite will be within 1,000km of a given location for no more than 3.5 minutes.
This means 3,000 satellites would give you a few minutes of illumination. To provide even an hour, you’d need thousands more.
Reflect Orbital isn’t lacking ambition. In one interview, Nowack suggested 250,000 satellites in 600km high orbits. That’s more than all the currently catalogued satellites and large pieces of space junk put together.
And yet, that vast constellation would deliver only 20% of the midday sun to no more than 80 locations at once, based on our calculations above. In practice, even fewer locations would be illuminated due to cloudy weather.
Additionally, given their altitude, the satellites could only deliver illumination to most locations near dusk and dawn, when the mirrors in low Earth orbit would be bathed in sunlight. Aware of this, Reflect Orbital plan for their constellation to encircle Earth above the day-night line in sun-synchronous orbits to keep them continuously in sunlight.
Bright lights
So, are mirrored satellites a practical means to produce affordable solar power at night? Probably not. Could they produce devastating light pollution? Absolutely.
In the early evening it doesn’t take long to spot satellites and space junk—and they’re not deliberately designed to be bright. With Reflect Orbital’s plan, even if just the test satellite works as planned, it will sometimes appear far brighter than the full moon.
A constellation of such mirrors would be devastating to astronomy and dangerous to astronomers. To anyone looking through a telescope the surface of each mirror could be almost as bright as the surface of the sun, risking permanent eye damage.
The light pollution will hinder everyone’s ability to see the cosmos and light pollution is known to impact the daily rhythms of animals as well.
Although Reflect Orbital aims to illuminate specific locations, the satellites’ beams would also sweep across Earth when moving from one location to the next. The night sky could be lit up with flashes of light brighter than the moon.
The company did not reply to The Conversation about these concerns within deadline. However, it told Bloomberg this week it plans to redirect sunlight in ways that are “brief, predictable and targeted”, avoiding observatories and sharing the locations of the satellites so scientists can plan their work.
The consequences would be dire
It remains to be seen whether Reflect Orbital’s project will get off the ground. The company may launch a test satellite, but it’s a long way from that to getting 250,000 enormous mirrors constantly circling Earth to keep some solar farms ticking over for a few extra hours a day.
Still, it’s a project to watch. The consequences of success for astronomers—and anyone else who likes the night sky dark—would be dire.
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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Tech
Here’s Every Country Directly Impacted by the War on Iran
On February 28, United States and Israeli forces launched a series of strikes on Iran, kicking off turmoil in the Middle East.
Pete Hegseth, the secretary of the Department of Defense, said in a recent press conference that the operation could last as long as eight weeks. President Donald Trump himself said in a press conference on March 2 that the administration projected the operation would last four or five weeks but had “the capability to go far longer than that.”
This week Iran has responded in turn, attacking Israel, regional US embassies and military bases, and other sites across the Middle East. Iran has peppered neighboring countries with hundreds of drone and ballistic missile strikes since the operation began. While many of these have been intercepted, over a thousand people have died in the region and multiple buildings have been damaged, including luxury hotels in Dubai, US military bases and embassies, and international airports and marine ports.
Israel has also started bombarding Lebanon, following strikes at the country by the Lebanese militant group Hezbollah.
The Trump administration has given various, and at times seemingly contradictory, justifications for the military action, citing everything from potential “nuclear threat” to unverified claims that Iran attempted to interfere in the 2020 and 2024 US presidential elections. As of March 5, Congress, which in the US has the sole power to declare war, has not done so.
The attacks have already disrupted supply chains, creating uncertainty for the oil and gas and fertilizer industries as key infrastructure has been targeted or shut down out of caution. Shipping traffic has halted along the Strait of Hormuz, a critical route.
As the conflict continues to escalate and expand, WIRED is tracking which countries have been affected and how. This article was last updated on March 5.
Iran
As of March 4, Iranian state media estimates that over 1,000 people have died in the country since the US-Israeli attacks began. Several schools and hospitals have been hit, according to Al Jazeera. The Israeli Air Force says it has struck Iran with over 5,000 munitions since the beginning of the operation.
Israel
Israel has faced retaliatory strikes from Iran. As of March 4, at least 11 people have died and over 40 buildings have been damaged in Tel Aviv, according to Al Jazeera.
Azerbaijan
On March 5, Azerbaijan said drone attacks launched from Iran had crossed over the country’s borders and damaged an airport building and two civilians. President Ilham Aliyev of Azerbaijan said that the country’s military forces “have been instructed to prepare and implement appropriate retaliatory measures,” according to Reuters. Iran has denied responsibility for the attacks, according to Al Jazeera.
Bahrain
Missile and drone strikes have targeted different locations in Bahrain, including a US naval base, according to the BBC. On March 2, Amazon reported that a drone strike occurred in close proximity to one of its data centers in the country. CNBC later reported that Iranian state media said that Iran had targeted the data center because of the company’s support of the US military.
Cyprus
On March 2, a drone strike hit a British air base in Cyprus, according to Reuters. It caused limited damage and no casualties. Greece, the UK, and France have lent defensive support to the country, according to a Bloomberg report.
Iraq
Since February 28, there have been reports of multiple Iranian strikes aimed at a US military base near the Erbil International Airport, according to the nonprofit monitoring group Armed Conflict Location and Event Data.
Jordan
Jordan’s armed forces have intercepted dozens of missiles since the start of the conflict. At least one Iranian-backed militant group in Iraq has claimed responsibility, according to the Associated Press. On March 2, the US Embassy in the country announced that all its personnel had temporarily departed.
Kuwait
Kuwait has endured multiple waves of Iranian missile and drone attacks since February 28. On March 2, US Central Command said in a statement that three US fighter jets were accidentally struck down by Kuwaiti air defenses during an attack that included Iranian aircraft, missiles, and drones.
Lebanon
Israel attacked southern Lebanon after the militant Lebanese group Hezbollah launched rocket and drone attacks against them. Lebanon prime minister Nawaf Salam subsequently banned Hezbollah’s military and security activities, according to Al Jazeera.
Oman
Oman’s Duqm commercial port has been hit by several drone attacks, according to Al Jazeera. Omani authorities have said at least one oil tanker off the country’s port of Khasab in the Strait of Hormuz has been attacked.
Qatar
On March 2, QatarEnergy posted on X saying that it would halt production of liquified natural gas following a military attack on its operational facilities in the country. It did not attribute the attack to any particular country. On March 3, it posted again, saying that it would also stop the production of additional products, including urea, polymers, methanol, and aluminum.
Saudi Arabia
Infrastructure in Saudi Arabia has been targeted with projectiles. On March 3, the US embassy in Riyadh, the country’s capital, was damaged following an attack. On March 4, Reuters reported that one of the Saudi Aramco’s largest domestic refineries of Saudi Aramco, the majority state-owned oil company, was targeted by an attempted drone attack.
Syria
Tom Fletcher, the United Nations undersecretary-general for humanitarian affairs and emergency relief, says that civilians and civilian infrastructure were under attack in several countries including Syria.
Turkey
On March 4, the Turkish Ministry of National Defence announced that NATO had intercepted ballistic munitions launched from Iran, and that munition fragments had fallen into Hatay, a province that borders the Mediterranean Sea and Syria. Iran has denied any missile launch towards the country.
United Arab Emirates
As of March 4, UAE Ministry of Defence officials say that the country has intercepted hundreds of drone and missile attacks from Iran. Despite the relatively high rate of interceptions, debris created by the fallout has still damaged areas of the country. In Dubai, the luxury hotel Burj Al Arab was struck by debris, as well as the Palm Jumeirah, a man-made island home to high-end hotels and apartments. On March 2, Amazon Web Services announced that two of its facilities were directly struck in the country, causing “elevated error rates and degraded availability.”
Countries Evacuating Citizens
On March 2, US assistant secretary of state for consular affairs Mora Namdar posted on X urging Americans to depart from several middle eastern countries due to “serious safety risks.” On March 4, Reuters reported that the US military has offered seats on military transport planes to Americans trying to leave the region.
Over a dozen countries have announced that they will be evacuating their citizens from the area or sponsoring repatriation flights, including the UK, Ireland, Germany and Italy.
Tech
OpenAI Had Banned Military Use. The Pentagon Tested Its Models Through Microsoft Anyway
OpenAI CEO Sam Altman is still in the hot seat this week after his company signed a deal with the US military. OpenAI employees have criticized the move, which came after Anthropic’s roughly $200 million contract with the Pentagon imploded, and asked Altman to release more information about the agreement. Altman admitted it looked “sloppy” in a social media post.
While this incident has become a major news story, it may just be the latest and most public example of OpenAI creating vague policies around how the US military can access its AI.
In 2023, OpenAI’s usage policy explicitly banned the military from accessing its AI models. But some OpenAI employees discovered the Pentagon had already started experimenting with Azure OpenAI, a version of OpenAI’s models offered by Microsoft, two sources familiar with the matter said. At the time, Microsoft had been contracting with the Department of Defense for decades. It was also OpenAI’s largest investor, and had broad license to commercialize the startup’s technology.
That same year, OpenAI employees saw Pentagon officials walking through the company’s San Francisco offices, the sources said. They spoke on the condition of anonymity as they aren’t licensed to comment on private company matters.
Some OpenAI employees were wary about associating with the Pentagon, while others were simply confused about what OpenAI’s usage policies meant. Did the policy apply to Microsoft? While sources tell WIRED it was not clear to most employees at the time, spokespeople from OpenAI and Microsoft say Azure OpenAI products are not, and were not, subject to OpenAI’s policies.
“Microsoft has a product called the Azure OpenAI Service that became available to the US Government in 2023 and is subject to Microsoft terms of service,” said spokesperson Frank Shaw in a statement to WIRED. Microsoft declined to comment specifically on when it made Azure OpenAI available to the Pentagon, but notes the service was not approved for “top secret” government workloads until 2025.
“AI is already playing a significant role in national security and we believe it’s important to have a seat at the table to help ensure it’s deployed safely and responsibly,” OpenAI spokesperson Liz Bourgeois said in a statement. “We’ve been transparent with our employees as we’ve approached this work, providing regular updates and dedicated channels where teams can ask questions and engage directly with our national security team.”
The Department of Defense did not respond to WIRED’s request for comment.
By January 2024, OpenAI updated its policies to remove the blanket ban on military use. Several OpenAI employees found out about the policy update through an article in The Intercept, sources say. Company leaders later addressed the change at an all-hands meeting, explaining how the company would tread carefully in this area moving forward.
In December 2024, OpenAI announced a partnership with Anduril to develop and deploy AI systems for “national security missions.” Ahead of the announcement, OpenAI told employees that the partnership was narrow in scope and would only deal with unclassified workloads, the same sources said. This stood in contrast to a deal Anthropic had signed with Palantir, which would see Anthropic’s AI used for classified military work.
Palantir approached OpenAI in the fall of 2024 to discuss participating in their “FedStart” program, an OpenAI spokesperson confirmed to WIRED. The company ultimately turned it down, and told employees it would’ve been too high-risk, two sources familiar with the matter tell WIRED. However, OpenAI now works with Palantir in other ways.
Around the time the Anduril deal was announced, a few dozen OpenAI employees joined a public Slack channel to discuss their concerns about the company’s military partnerships, sources say and a spokesperson confirmed. Some believed the company’s models were too unreliable to handle a user’s credit card information, let alone assist Americans on the battlefield.
Tech
Don’t Risk Birdwatching FOMO—Put Out Your Hummingbird Feeders Now
Though most people associate the beginning of March with the hopefulness of spring and the indignities of daylight saving time, there’s another important event taking place yards all over the country: hummingbird season.
While many species of hummingbirds can be seen in regions year-round, others are migratory, and this time typically marks their return from wintering grounds in Central and South America. These tiny birds can lose up to 40 percent of their body weight by the time they arrive here after having flown thousands of miles, and since many flowers haven’t bloomed yet, nectar feeders can be a source of essential fuel.
Though I test smart bird feeders year-round, I don’t use hummingbird feeders as often as I should, as it’s imperative that they be cleaned and refilled with new nectar every two or three days (a ratio of 1:4 granulated sugar to water is best, and avoid any dyes or additives) to prevent deadly bacteria and mold, and I don’t always have the time.
But if you are going to invest the energy in maintaining a hummingbird feeder, right now is the best time, as you have a chance to see migratory species you might not otherwise encounter, such as black-chinned hummingbirds. A smart feeder helps you ID them, whether they’re stopping at your feeder on their way north or arriving at their final destination.
Birdbuddy’s Pro is the smart hummingbird feeder I recommend and use myself when I’m not actively testing. The app is easy to navigate and sends cleaning reminders, the built-in solar roof keeps the battery charged, and, unlike other feeders, only the shallow bottom screws off for refilling. No having to pour sticky nectar through a narrow opening, or turn a giant cylinder upside down and risk spilling.
Note that it’s not perfect; the sensor is inconsistent and doesn’t capture every hummingbird that visits, but for the camera quality (5 MP photos, 2K video with slow-motion, 122-degree field of view) and ease of use, it’s a foible I’m willing to put up with. If you already have another Birdbuddy feeder, the hummingbird feeder images and videos will integrate seamlessly into your app feed.
Right now, the feeder is 37 percent off on Birdbuddy’s website—a deal I usually don’t see outside of shopping events like Black Friday or Amazon Prime Day. Note that the feeder only runs on 2.4 GHz Wi-Fi, and while it is fully functional without a subscription, a Birdbuddy Premium subscription will let you add friends and family members to your account so they can see the birds as well. That’s $99 a year through the app.
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