Posted on 08/15/2025 7:01:50 AM PDT by Red Badger
These fins are said to be among the largest aerodynamic control surfaces ever built for a rocket.
Grid fin for the next generation Super Heavy booster. SpaceX/X
Elon Musk’s SpaceX has redesigned some parts of its colossal Mars-bound Starship to improve its stability and control.
The most notable change is the removal of a landing fin from the Super Heavy booster, which will now use three redesigned grid fins that are 50% larger and stronger to improve vehicle control during descent.
The announcement was made on Wednesday via a post on X, where SpaceX shared images revealing the complex, honeycomb-like surface of the new grid fins.
The first grid fin for the next generation Super Heavy booster. The redesigned grid fins are 50% larger and higher strength, moving from four fins to three for vehicle control while enabling the booster to descend at higher angles of attack. pic.twitter.com/Nc6bavBHD8
— SpaceX (@SpaceX) August 13, 2025
Interestingly, these fins are said to be among the largest aerodynamic control surfaces ever built for a rocket.
Weighing in on the redesign, SpaceX CEO Musk shared the company’s announcement on X, adding a characteristically concise comment: “Best part is no part.”
Reports cite the development in the wake of recent test flight failures.
Improving descent and catch
To control the rocket’s position and flight path during descent and re-entry, grid fins manipulate the air passing through them.
With their larger surface area and increased strength, the new grid fins will give the booster greater maneuverability to descend at a steeper, more controlled angle during the landing phase.
The new fins are also being integrated into the booster’s recovery system.
These redesigned parts will align with the launch tower’s catch arms, which are designed to grab the descending booster out of the air.
SpaceX has added a new catch point to the booster and mounted the fins lower to align well with the tower’s arms. This change allows the tower to catch the returning rocket directly, eliminating the need for a landing pad.
Reportedly, the lower position of the fins also protects them from the intense heat of the rocket’s engines.
Moreover, the social media post mentioned that the fins’ internal parts, like the shaft, are now inside the booster’s main fuel tank for better protection.
VIDEO AT LINK.............
Previous failed attempts
The path to Mars hasn’t been smooth for SpaceX and its ambitious Starship program.
The redesign comes after the most recent failed test flight for the fully integrated rocket in May.
After the test flight, the Super Heavy booster failed to return to its launchpad and crashed into the Gulf of Mexico instead.
The main ship, meanwhile, continued its flight over the Indian Ocean before it too exploded.
In another incident in June, the rocket’s upper stage exploded while on a test stand during preparations for SpaceX’s tenth Starship flight.
The company is gearing up for its 10th orbital flight test, a critical demonstration of the new design.
Reportedly, the next Starship launch attempt could occur as early as Saturday, August 16, with a launch window between 6:30 am and 8:30 pm local time.
SpaceX typically keeps launch dates under wraps until closer to the time.
It is based on maritime hazard warnings from the US, which cover the waterways and sea areas around SpaceX’s Starbase facility in southern Texas.
“Navigation hazards from rocket launching activity may include, free-falling debris and/or descending vehicles or vehicle components, under various means of control,” the advisory noted, as the Independent reported.
Musk indicated in an X post earlier this month that SpaceX was aiming to launch Starship in mid-August.
The billionaire has set an ambitious goal to send the world’s largest rocket, with Tesla’s humanoid robot Optimus on board, to Mars by the end of 2026.
Given the recent failures and NASA’s budget cuts, the plan may be subject to further delays.
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ABOUT THE AUTHOR Mrigakshi Dixit Mrigakshi is a science journalist who enjoys writing about space exploration, biology, and technological innovations. Her work has been featured in well-known publications including Nature India, Supercluster, The Weather Channel and Astronomy magazine. If you have pitches in mind, please do not hesitate to email her.
cerium, neodymium, and lanthanum is why
Those can be found here, but demand is ever increasing.
The fins are used to steer the booster into position for the catch. Steering is a combined effort of using the gimbaled engines and the fins. Engine firings are limited by fuel reserves, the fins are "free".
Mars has.lots of water enough to cover the surface to a depth of a kilometer of all extracted and melted.
ars is the only other body in the solar system with water and CO2 that humans could step on. Mars has enough atmosphere that humans don’t need full pressure suits with 100% O2 in the masks and compression fabric suits and thermal suits humans can walk and not boil our blood. We need about 1 psi of pressure on the skin to not boil fluids at body temps. A sufficiently tight compression garment can keep in a couple.of psi and with pure O2 we could walk around like that. No need for bulky full bubble suits. The SpaceX launch suits are essentially this tech already. Only the helmets have air the rest of the suit is compressed down on the skin of the wearer.
They are little bitty compared to Saturn F-1s.
How very... communal... of you to try to re-invest someone else's earnings.
Elon is doing this on his dime and it is much more than just collecting a few rocks and you are entirely off on the assessment of available resources on Mars.
Do you know who the hells gonna pay for the upkeep on that self absorbed fantasy?
I think is going to be nice.
If the Sun starts getting squirrely... being further away from it makes more sense though.
Titan has everything we need in either ice or liquid form, has a megnetosphere, etc... It's just REALLY cold.
Mars will be important... not to terreform, but as a jump off/transfer point.
Then you and your kind can donate for the upkeep.
It’s the solar wind that stripped Mars atmo once it’s core cooled and no longer was generating a large magnetic field to produce a magnetosphere....NASA has a plan to create a large plasma bubble and an artificial magnetosphere. Then Mars could hold an atmosphere it has the mass to hold one and did for a long time while it has the protection of its magnetosphere Mars once had a sense atmo, liquid oceans and was much warmer. It was conducive to life hundreds of millions of years before earth cooled enough to hold liquid water on its surface. It’s entirely possible life evolved there first and we know meteorites have come from Mars to Earth and landed in one piece with the internal temp of the inside not getting above a hundred F from the deep cold of space to touchdown the what pulse is fast and largely contained to the other layers of meteorites.
https://astrobiology.nasa.gov/news/how-to-give-mars-an-atmosphere-maybe/
Get the plasma bubble big enough and you deflect the solar wind in its shadow.
Duh. I was talking about the traditional fin design.
We will. But so will you. ;-D
What is the current thinking on feasibility of terraforming Mars to have breathable atmosphere, livable temp and growing plants for oxygen?
I can see Mars being turned into a giant manufacturing facility.
“Those who say a thing cannot be done, should not interrupt those who are doing it.”
A lot of people have said a lot of things “can’t be done”... until that first person figures out how to do it.
All this expense to collect few martian rocks ... The money will be much better spent on making planet earth a better place.
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Wrong; this is an effort to permanently live, to colonize Mars. on the counts of water: wrong there is lots of water on Mars; air can be made from the regolith; temperatures are much warmer down in Valles Marineris during summer, daytime temperatures may reach highs of about 70F.
Spending money to make Earth a better place according to whom and which version? And when a more than a mile diameter rock hits, will that make Earth a better place too, since it will be an ELE event?
There has never been any other type of fin on the Space-X rockets.
As I said, a domed atmosphere is about the only practical way to get an atmosphere of any kind. If you tried to trap an atmosphere, without a dome, it’d be like being near the top of Everest.
According to Grok.
Mars can hold an atmosphere, but its small size and low gravity make it difficult to retain a thick, Earth-like one. Here’s a concise explanation:
Gravity and Size: Mars has about 38% of Earth’s gravity due to its smaller mass (about 11% of Earth’s) and radius (roughly half Earth’s). Lower gravity means less ability to hold onto atmospheric gases, which can escape into space over time, especially lighter molecules like hydrogen.
Current Atmosphere: Mars has a thin atmosphere, primarily carbon dioxide (95.3%), with nitrogen (2.7%) and argon (1.6%). Its surface pressure is only about 0.6% of Earth’s (6 millibars vs. 1013 millibars), too low to support liquid water or human breathing without aid.
Historical Atmosphere: Evidence like ancient riverbeds and minerals suggests Mars once had a thicker atmosphere, possibly supporting liquid water 3-4 billion years ago. Its small size, lack of a strong magnetic field (unlike Earth’s, which deflects solar wind), and geological inactivity led to atmospheric loss over time. Solar wind stripped lighter gases, and the planet’s weak gravity couldn’t retain them.
Comparison: Larger planets like Earth or Venus have stronger gravity, helping retain denser atmospheres. Mars’ small size limits its ability to hold a substantial atmosphere without external intervention (e.g., terraforming).
Could Mars hold a thicker atmosphere if artificially replenished? Theoretically, yes, but maintaining it would require ongoing efforts due to its low gravity and solar wind exposure. If you’re curious about terraforming possibilities or specific atmospheric data, I can dig deeper or check for recent discussions on X or the web. Want to explore that?
Asymmetric eh?
I am surprised at a very visible external control surface change, when earlier “unofficial discussions” among “the experts” claimed the booster problems were internal tank and fuel problems.
Combining solutions into one re-design of the booster?
Gravity could be simulated with exercise suits, but there is no way to give Mars a solid atmosphere without increasing it’s mass to give it the gravity to hold one.
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