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Mars could have a Leap Day like Earth but way more complicated
February 29, “leap day”, is an oddity on the calendar that occurs every four years in an attempt to sync up the Gregorian calendar (the calendar most of the world uses to keep time) with Earth’s rotation around the sun.
One calendar year on Earth is 365 days long; however, the Earth actually takes 365.2422 days to lap the sun. That puts the planet roughly a quarter of a day behind at the end of each year.
To maintain consistency and ensure the seasons line up each year, an extra day was added to the already short month of February — a modification that happens every four years. But even this doesn’t fully solve the problem; additional tweaks are needed.
For instance, if a year is divisible by 100, there’s no extra day — unless the year is divisible by 400. That means that 1700, 1800 and 1900 did not have a leap day, but 2000 did. This adjustment ensures that Earth is as close as possible to the same point in its orbit in consecutive calendar years and keeps our seasons inline.
Unsurprisingly, Earth is not the only planet that needs leap days. The phenomenon could occur on other planets in our solar system as well as those around other stars. That’s because you can’t fit an exact number of spins into one trip around the sun for any planet. There’s usually going to be something left over. Leap days on other worlds, such as Mars, could be more complicated than those here on Earth.
One year on Mars lasts for approximately 668.6 Martian days. (A Martian day is called a sols and equals 24 hours, 39 minutes, and 35.244 seconds.) Future inhabitants might decide that a year on the red planet will be described as 668 days. How do we adjust?
Over the decades, many different ideas for the Martian calendar have been proposed. The most popular one, called the Darian calendar, was created in 1985 by Tomas Gangale.
According to Gangale, the Martian calendar would feature 24 months, each named for the Latin and Sanskrit words for the constellation of the zodiac, like Sagittarius and Dhanus, and so forth. The first five months in each quarter would have 28 Martian days (or sols), with the sixth having only 27. Even-numbered years would total 668 days and odd-numbered years would have 669. The exception to that rule: even-numbered years that were divisible by 10.
Another option was proposed by Michael Allison, a retired NASA scientist. In his version, the Martian calendar would have 668-days divided into 22 months, each totaling 30 or 31 days, similar in fashion to Earth. To make sure the seasons lined up, all years divisible by five will have three leap days, bringing the total to 671.
So which of these calendars do scientists use to keep track of time on Mars? Currently, none.
Instead, they use two systems to keep track of time: one counts the number of Martian days since the start of a mission, and the other keeps track of where Mars was in its orbit at that time.
Right now scientists don’t care if the seasons line up perfectly with the calendar, but that may change when you add humans into the mix. NASA and other space agencies around the world have their sights set on Mars. Once humans land on the red planet and spend significant time there, we are going to need a common calendar to keep track of seasons.
The Tesla Semi is entering a new Pilot Program with Paper Transport, LLC (PTI), a Wisconsin-based transportation provider. The company will test the Semi’s Long Range configuration through “dedicated operations within the Chicago market.”
Chicago presents an interesting challenge for the Semi, as it will be a colder-weather climate that will test the Semi’s ability to operate in lower temperatures and in potentially large accumulations of snow. This is something Tesla has been testing with the Semi in Alaska and even in Northern California during the colder months, but Chicago will present a truly tough midwestern winter.
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PTI says it is using the Semi to evaluate its strategy of reducing transportation emissions while maintaining performance, reliability, and cost efficiency. These are major arguments for the Semi being introduced into new fleets.
CEO of PTI Tyler Ellison said:
“PTI has been a leader in sustainable transportation solutions for over 15 years. We take a consultative approach to helping customers identify and implement the right transportation solution for their network. Our partnership with Tesla expands our portfolio alongside renewable natural gas and intermodal, giving customers more ways to reduce Scope 3 emissions without compromising service or economics.”
PTI is far from the first company to adopt the Semi within a fleet, as Tesla entered strategic agreements with PepsiCo. and its subsidiary Frito-Lay for a Pilot Program that extended throughout the California region.
Tesla has let companies like those utilize the Semi to determine whether it would be suitable for their operations. Additionally, Tesla gets valuable information regarding the Semi’s performance, knowing what to improve and what is ideal for companies that will utilize the all-electric truck for regional and nationwide logistics.
PTI plans to utilize the Long Range configuration, which is priced at $290,000 and features a range of approximately 500 miles, a three-motor powertrain, up to 800 kW of drive power, and consumption of just 1.7 kWh per mile.
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VP of Maintenance at PTI, Bryan Ellen, added:
“We are excited to partner with Tesla, leveraging their ever-evolving technology. We are bullish in our estimation of the parallels available between our dedicated model and the efficiency of their fully electric Class 8 tractor. We anticipate a growing synergy between our businesses as we work to facilitate this sustainable solution for our customers.”
PTI has logged more than 87 million miles using sources like compressed and renewable gas, but now is looking to take it a step further with fully electric operations.
Tesla revealed on Monday that it is building a new autonomous vehicle at Gigafactory Texas, its plant just outside of the City of Austin. This particular vehicle will be geared toward those who are in need of a wheelchair-accessible car that would require no human driver for operation.
According to a new report from Wired, Tesla’s Senior Policy Advisor, India Herdman, told members of the Washington D.C. City Council on Monday:
“We are in development for a purpose-built, wheelchair-accessible autonomous vehicle. We know that paratransit can be very difficult, and people who are confined to wheelchairs permanently should still be able to move around freely, so that is an active product being built by Tesla in Texas.”
This builds upon what CEO Elon Musk said last year on X, which confirmed the company was working on accessible rides within its Robotaxi platform, which currently is confined to the Model Y.
Absolutely
— Elon Musk (@elonmusk) September 19, 2025
Tesla is also developing the Cybercab, which started employee rides last week. However, this vehicle is not necessarily geared toward wheelchair accessibility.
That leaves a major gap in the autonomous ride-sharing program that Tesla is attempting to build; the company has been pretty clear that it does not want to complicate its manufacturing lines by bringing in a wide array of body styles.
However, it seems necessary to have something larger that could help transport people to appointments when they cannot drive. For wheelchair accessibility, the Robovan, which was unveiled at the “We, Robot” event in October 2024, seems to be the most ideal solution:
Herdman did not indicate whether she was referring to the Robovan or if Tesla is building yet another body style that is geared toward full autonomy but also caters to the handicapped.
Tesla might need to develop something specifically for the handicapped in order to align with the Americans with Disabilities Act, which prevents discrimination against people with disabilities in transportation services. Uber was hit with a lawsuit late last year for “refusing to reasonably modify its policies, practices, or procedures where necessary to avoid discriminating against riders with disabilities.”
Tesla would obviously like to avoid this.
It will be interesting to see what Tesla will do with this project, and whether it will introduce something new to the market or just continue with the Robovan.
Tesla weirdly confirmed that its steering wheel-less and pedal-less Cybercab vehicle is now in the process of giving employees rides, a huge milestone for the vehicle program.
But the entire thing was super strange. On Friday, Tesla released a video stating that there was “Cool news from Giga Texas” and that employees were now taking rides in Cybercabs that have no manual controls. The units seen on public roads are engineering vehicles that have manual controls inside, a necessity as Tesla moved through the testing phase.
However, Tesla removed the video and reposted it shortly after with a more vague title. It seems like the employee rides are still going, but the video was adjusted slightly. The initial upload showed employees doing things like watching movies and adjusting the climate, but these snippets were removed in the second upload.
Cool news from Giga Texas pic.twitter.com/gvbG456Tzw
— Tesla Robotaxi (@robotaxi) July 11, 2026
Both images below were uploaded with the first video, but were removed after Tesla re-uploaded the announcement. These are not available in the second upload
Credit: Tesla
Credit: Tesla
Nevertheless, the announcement from Tesla is that the Cybercab is operating with employees inside who can control the vehicle’s audio, video, climate, and destination settings through their smartphone app.
Tesla has already been testing Cybercab engineering units, but last month, it was able to self-certify for SAE Level 4, which would enable unsupervised self-driving in Texas. The company is moving toward that, and the plans have always been to launch Cybercab rides this year.
The Cybercab is potentially looked at as the next generation of Tesla’s mobility leg. For the past 15 years, the company has been known as somewhat of an automaker, among many other things. However, these passenger vehicles that Tesla has manufactured are now moving into a new realm, as they will eventually drive themselves with no supervision thanks to the Full Self-Driving suite.
The Cybercab is just the next step of that: a true vehicle developed for the sole purpose of ride-hailing. It has no human controls, it has only two seats, and it will get passengers from Point A to Point B with no awkward driver, no need for manual inputs, and with no stress.
Tesla is moving forward with other developments related to the Cybercab project as well. However, the big announcement will come when Tesla finally announces that it is launching Cybercab rides to the general public, something that it plans to launch either late this year or early 2027.
Tesla Semi enters new Pilot Program with interesting challenge
Tesla is building a wheelchair-accessible Robotaxi
