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Tidal Power Faces a Fickle Future with Rising Seas ...
Ocean tide power, or tidal energy, is a form of renewable energy that harnesses the gravitational interaction between the Earth, Moon, and Sun to create electricity from the natural rise and fall of ocean tides. This clean energy is generated by using specialized structures like tidal barrages, which act like dams across bays, or tidal turbines, underwater propellers that convert the kinetic energy of tidal currents into electricity. While expensive to build, tidal energy offers a reliable and predictable power source with significant potential for sustainable energy systems. 
How it Works
Gravitational Pull: The consistent pull of the moon, sun, and Earth's rotation creates predictable cycles of high and low tides.
Harnessing Movement: This natural water movement is captured and converted into electricity through two main methods:
Tidal Barrages: A dam-like structure is built across an estuary or bay, creating a tidal basin. During high tide, water flows into the basin, and during low tide, it's released through turbines in the barrage to generate power.
Tidal Turbines: These underwater devices, similar to wind turbines but built to withstand water's greater density, are placed in fast-flowing tidal streams. As the water moves past, it spins the turbine blades, which in turn drive a generator.
Types of Tidal Energy Systems
Tidal barrages: Use dams to create a large difference in water level, storing potential energy.
Tidal lagoons: Similar to barrages but are partly enclosed areas of the ocean, allowing water to flow in and out through turbines.
Tidal stream generators: Place turbines on the seafloor to capture the kinetic energy of strong tidal currents.
Advantages
Clean Energy: Produces minimal greenhouse gases compared to fossil fuels.
Predictable: Tidal patterns are consistent and predictable, providing a reliable power source.
High Power Output: Because water is much denser than air, tidal turbines can generate a high amount of electricity from a relatively small device.
Disadvantages
High Costs: Initial construction costs for tidal energy systems are substantial.
Geographic Limitations: Economically viable tidal power generation requires locations with significant tidal ranges, which are not found everywhere.
Environmental Impact: The presence of turbines or barrages can have negative effects on marine life and ecosystems

Cygnus XL spacecraft experienced engine trouble during its journey. The mishap temporarily delayed the delivery of more than 11,000 pounds of supplies to astronauts aboard the ISS. When the spacecraft's main engine shut down earlier but the Cygnus XL and its nearly five tons of supplies made it to ISS
What did those 11,000 pounds of supplies contain? Essential materials for research, maintaining the ISS, and various other provisions to support the ISS crew through early 2026. This stuff is priceless to those ISS astronauts, and the loss of it would have been a major blow.

Malfunctions are an inevitable part of supply chain logistics in space

For now, the ISS crew is no doubt happy to have all that cargo, which includes food, oxygen, and nitrogen, plus spare parts for the station's waste filtering system that gives them their fresh drinking water.

From the outset, SpaceX's tenth Starship test flight in late August looked like a near-perfect success. The massive rocket had a clean launch from Starbase, sailed smoothly into space, and guided itself to a splashdown in the Indian Ocean within a mere few feet of its target. It's the kind of accuracy that would have seemed impossible only a few years ago.
But once the replay videos began circulating, engineers were swift to spot something concerning. The sleek stainless steel sides of the Starship weren't gleaming silver anymore, having been replaced with streaks of a rusty orange hue. Elon Musk later explained that the color came from three experimental metallic tiles that had oxidized during reentry. While SpaceX had hoped for a different result, they noted that some tiles were intentionally removed to test the vehicle's response, and in turn they have now gained valuable data that will help improve the next iteration of the Starship.

Although the mission can still be considered a success, especially when you factor in how many SpaceX rockets have exploded this year, the lesson still hits hard. If Starship is ever going to fly people to orbit, let alone try to go to the Moon or Mars, it needs a heat shield that works every time and can be used again. And right now, that piece of the puzzle is still missing.

Bill Gerstenmaier, a former NASA veteran who is now in charge of build and flight reliability at SpaceX, summed up the result in a straightforward way: "The metal tiles... didn't work so well." Luckily, the problem wasn't a disaster, as the Starship's stainless-steel hull held up. However, the tiles rusted quickly in the high-oxygen, high-temperature environment of reentry. While it may have suffered some serious burns, at least it didn't go up in flames like the previous SpaceX Starship which exploded in June 2025. 

The result is not exactly surprising when you consider that NASA played with the same idea in the 1970s, with those tests never making it past the lab. The space shuttle instead relied on 24,000 notoriously fragile ceramic tiles that were the only thing that stood between the orbiter and obliteration. SpaceX is now testing a new "crunch wrap" material to better seal gaps between tiles, having already shown signs of promise on the most recent flight in the form of darker spots against the surrounding burnt white metal.

Metal tiles promised simplicity, but the flight proved they're more complicated than initially believed. They may resist cracks and chips better than ceramic, but if they can't survive the most critical part of the mission, they're a dead end.

The patches of white residue where heat seeped through gaps, eroding the protective layer beneath. Engineers have been quick to identify potential remedies to the patches of white residue where heat seeped through gaps, eroding the protective layer beneath. SpaceX now aims to seal the tiles using the new "crunch wrap" approach, which will basically wrap each tile so they interlock more securely, fixing the weak spot without adding the complexity of traditional gap fillers.

That's what Flight 11, expected as soon as October, is meant to prove. If it works, Starship will take another step toward true reusability. Beyond that, SpaceX plans to roll out the upgraded "V3" Starship with improved Raptor engines and refined shielding. Only once that vehicle flies will we know if Musk's dream of a massive stainless steel rocket that can launch, land, and relaunch in quick succession is realistic. SpaceX's ambitions now hinge on perfecting a heat shield that can comfortably handle reentry again and again. Until that problem is solved, Mars and the Moon remain firmly out of reach.

A "NewMars lunar inflatable garden" does not refer to a specific, named project but describes an inflatable greenhouse concept being developed by NASA and others, primarily the University of Arizona. These Bioregenerative Life Support Systems (BLSS) use plants to create a sustainable, closed-loop environment for long-duration space missions, including future outposts on the Moon or Mars.
Core life support systems
Air revitalization: Plants use photosynthesis to absorb the carbon dioxide exhaled by astronauts and convert it into breathable oxygen. This process is more sustainable and autonomous than relying on oxygen tanks or physiochemical scrubbers alone.
Water recycling: Water vapor released by plants through transpiration is collected and purified. This system, along with recycling wastewater from the crew, provides clean water for drinking and irrigation.
Food production: The garden grows fresh, nutritious food, supplementing the freeze-dried and pre-packaged meals typically consumed on missions. This provides essential vitamins and minerals and improves crew morale.
Waste management: Biological waste, including inedible plant biomass and human waste, can be recycled. Microorganisms in the BLSS break down the waste into nutrients that are then used to feed the plants.
Inflatable garden design
Radiation shielding: The Moon has no atmosphere or magnetosphere to protect against space radiation. Inflatable greenhouse prototypes are designed to be covered with a layer of lunar soil (regolith) after deployment to shield the plants from harmful cosmic rays.
Artificial lighting: With the garden buried for protection, plants are grown under controlled LED lights. These lights are highly energy-efficient and provide the optimal light spectrum for photosynthesis. Some concepts also explore using rotating mirrors to direct natural sunlight into the buried greenhouse.
Hydroponics: To save weight and avoid using alien soil, plants are grown using a hydroponic system. Nutrient-rich water is circulated directly over the plant roots, which are typically supported by a cable-based system.
Durable materials: The inflatable structures are made from high-strength, flexible materials that can be compactly stowed for launch. The material for NASA's LIFE (Large Integrated Flexible Environment) habitat, which includes a garden system, is made of Vectran, a fiber stronger than steel.
Benefits beyond physical survival
Psychological well-being: For long, isolated missions, exposure to greenery, gardening, and fresh food has a significant positive impact on the mental health of astronauts. It creates a connection to Earth and a sense of normalcy.
Increased sustainability: The closed-loop nature of the BLSS reduces dependence on resupply missions from Earth. This minimizes launch costs and makes long-duration missions to distant locations like Mars more feasible

For a four-person Mars mission, the food tonnage would be between 6.6 and 15 tons, depending on the total mission duration and whether resupply missions or local food production are used. The total mass includes the food itself plus the necessary packaging. Key factors influencing food tonnage Mission duration 

A Mars mission is typically estimated to be a round trip of 2 to 3 years, with a stay on the Martian surface. The total mass of food required is a direct product of the mission length. 

Average daily mass:
A standard estimate for space food is about 1.83 kg (4 lbs) per astronaut per day.Total food mass calculation: Assuming a 2.5-year (912.5-day) mission, the total food tonnage for four astronauts would be calculated as follows:
1.83 kg/person/day * 912.5 days * 4 astronauts =6,680 kg
This equals about 6.7 metric tons.

Mission architecture 
The overall mission plan significantly affects the food tonnage that must be launched from Earth. 

All prepackaged:
If all food is launched from Earth, the tonnage would be at the high end of the estimate, especially if extra supplies are included for safety margins or emergencies. Some proposals suggest sending supply caches to Mars ahead of the crew.

Partial local production:
Integrating local food production, such as growing crops in a Martian habitat, could dramatically reduce the amount of food that needs to be carried. A diet supplemented with fresh vegetables and other produce could significantly lower the initial launch mass. 

Food type 
The composition of the food is a critical variable. Freeze-dried vs. whole food: Freeze-dried or dehydrated food contains much less water, making it far lighter to transport than whole food.Packaging: Packaging, while individually light, adds up over the course of a multi-year mission. Innovations in lighter, more efficient packaging could contribute to reducing overall tonnage. Contingency supplies Mission planners must also account for potential issues and emergencies. 

Buffer stock: A contingency supply of food is often included to cover mission extensions or unforeseen problems, adding significant mass to the total payload. For a 4-person, 900-day mission, a 500-day contingency supply could add over 10 tons of mass. 

Example calculation 
Here is a breakdown of a potential scenario for a four-person, 2.5-year (913-day) Mars mission. Daily food intake per person: 1.83 kg

Total crew-days:4 people * 913 days=3,652 person-days
Total food mass: 3,652 person-days * 1.83 kg/person/day=6,698 kg
Base food tonnage: Approximately 6.7 metric ton

Perishable food items are foods that will spoil, decay, or become unsafe to eat if not kept refrigerated or frozen, including meats, poultry, seafood, dairy products, eggs, cooked leftovers, and most fresh fruits and vegetables, especially those that are cut, chopped, or lack a hard outer skin.
Meat, Poultry, and Fish
Raw meats: such as ground beef, steaks, lamb, and pork.
Poultry, like fresh chicken, turkey, and duck.
Fish and seafood, including fresh fish, shrimp, lobster, and all types of shellfish.
Deli meats, which are processed and sliced.
Dairy and Eggs
Milk, cream, and yogurt.
Cheese, including soft and hard varieties.
Butter .
Eggs .
Fruits and Vegetables
Most fresh fruits and vegetables are perishable, particularly those without a hard skin like berries, tomatoes, and lettuce.
Cut or chopped produce, as this increases the rate of decay.
Cooked Foods and Leftovers
Any cooked leftovers, such as stews, cooked rice, and prepared meals.
Prepared salads: and other dishes containing perishable ingredients.
Other Perishables
Drinks with live bacteria, like some juices.
Sauces and dips: (like hummus, pesto, and sour cream), once opened.
Some baked goods, especially those with dairy or cream.

Non-perishable food items are shelf-stable and do not require refrigeration, including canned goods (fruits, vegetables, meats, soups, beans), dried goods (rice, pasta, oats, dried fruit, nuts, seeds, jerky, dried beans), shelf-stable milk and juices, and pantry staples like peanut butter, honey, cooking oil, sugar, and crackers.
Canned & Pouched Foods
Proteins: Tuna, salmon, chicken, and beans.
Vegetables: Corn, green beans, carrots, and other vegetables.
Fruits: Peaches, pineapple, applesauce, and other fruits.
Soups & Stews: Meat-based, vegetable-based, and other ready-to-eat options.
Dried & Grains
Grains: Rice, oats, pasta, and couscous.
Legumes: Dried beans, lentils, and peas.
Snacks: Nuts, seeds, dried fruits (raisins, apricots), trail mix, jerky, and granola bars.
Pantry Staples
Spreads: Peanut butter, jelly, and other nut/seed butters.
Sweeteners & Sauces: Honey, sugar, syrup, and jarred pasta sauces.
Oils: Vegetable oil and other cooking oils.
Baking Ingredients: Pancake mix and powdered milk.
Beverages: Shelf-stable powdered milk, bottled water, and juice boxes.
Other Shelf-Stable Items Crackers and melba toast, Ready-to-eat meals (like MREs), and Hard candies

For a four-person Mars crew, the total water tonnage required would be around 23 tons for a 30-month mission, based on advanced recycling technology with a 98% recovery rate. The actual tonnage could be significantly higher without such systems. 

The total mass for a Mars mission is determined by several factors: 
Mission duration:
A typical round trip to Mars, including time on the surface, is estimated to last 32 to 38 months, or about 1,000 to 1,140 days.

Water recycling efficiency:
Modern systems, like the one on the International Space Station (ISS), can recycle over 98% of the water from astronaut breath, sweat, and urine.

Water requirements per person:
An astronaut needs approximately 1 gallon (3.8 kg) of water per day for drinking, food preparation, and hygiene. Water tonnage calculation Using the approximate 32-month (960-day) mission duration, here is the breakdown of the water tonnage for a four-person crew: 

1. Calculate the gross water requirement Daily consumption per person: 3.8 kg.Total daily consumption (4 crew): 3.8 kg * 4=15.2 kg Gross mission total: 15.2 kg/day * 960 days=14,592 kg. 

2. Factor in water recycling Total water recycled (98%): 14,592 kg * 0.98=14,290.1 kg.
Makeup water needed: 14,592 kg -14,290.1 kg =301.9 kg. 

This figure (301.9 kg) represents only the water needed to replace what is lost from the recycling system, but does not include the initial supply for the journey itself. 

3. Determine the initial water supplyThe total tonnage launched from Earth would need to cover the water lost through recycling, provide a safety reserve for emergencies, and possibly function as a radiation shield during the deep-space transit. A more comprehensive NASA estimate calculates total requirements, including water for food production and other needs. For a four-person, 500-day mission, one estimate puts the total water mass at 3,450 kg (about 3.5 tons) with closed-loop systems. Scaling this figure to a 32-month mission gives us a more realistic total. 

NASA 500-day estimate: 3.5 tons for 4 crew.Annualized NASA estimate: 3.5 tons * (365/500)=2.56 tons/year
32-month mission estimate: 2.56 tons/year * (32/12)=6.83 tons. The critical role of water for a crewed Mars mission The wide range of water tonnage estimates highlights the complexity of mission planning. 
Radiation shielding: Because water is an effective material for blocking space radiation, some mission designs include launching extra water from Earth to serve as radiation shielding during the transit to Mars.

In-Situ Resource Utilization (ISRU):
To significantly reduce launch mass, future missions will rely on ISRU to create water and fuel from Martian resources.Mass trade-offs: A mission might carry more water from Earth as a backup, or rely on ISRU, which requires more complex equipment and energy. Based on these considerations, a modern Mars mission would launch with an initial water tonnage in the single-digit range, supplemented by highly efficient recycling systems. The total mass that must be accounted for over the full mission lifetime, however, would be closer to the 23-ton figure, with most of it being continuously recycled.

For a Mars mission carrying a 40-metric-ton payload, a Starship uses approximately 676 metric tons of fuel for the Earth departure burn after being fully refueled in Earth's orbit. The vehicle is powered by Raptor engines that burn liquid methane and liquid oxygen.

For a propulsive landing on Mars with a 40-ton payload, a SpaceX Starship would need approximately 30 to 40 tons of methalox propellant for the final landing burn. The Raptor engines use sub-cooled liquid methane (CH₄) as fuel and liquid oxygen (LOX) as the oxidizer.

For a Starship with an 85-metric-ton dry mass and a 10-metric-ton payload to return from Mars, it would need approximately 340 metric tons of fuel synthesized on the Martian surface. The overall mission requires significant fuel production and refueling in low Earth orbit (LEO)