In a rare instance of environmental success, the United Nations has just announced it believes the damage to the Earth’s protective ozone layer will be fully restored by the year 2050. This stands in stark contrast to the increasing alarm over the climate emergency, caused by an increasing greenhouse effect.
Both the ozone layer and the greenhouse effect ultimately help control how much ultra-violet (UV) radiation from the sun reaches the Earth’s surface, and how much infra-red (IR) radiation escapes to space. Both these forms of radiation have a critical impact on the habitability of a rocket planet.
Clearly controlling this radiation is a pressing issue on Earth. But it also presents a challenge for those who dream of colonising Mars.
Ultra-violet radiation is a form of light which has a wavelength ranging from 10 – 400 nanometers (1nm is 0.000000001 metres in length). This is shorter and more energetic than visible light. By contrast, the wavelength of a typical 4G phone network is a few tens of centimetres.
Solar-UV can drive the production of the essential Vitamin D in human skin, but excess levels can cause an array of health problems including sunburn, skin cancer and cataracts. It can also damage plants and harm crop production.
On Earth, almost all solar UV is absorbed by the ozone layer, a region of the Earth’s atmosphere extending from about 15–30km in altitude. Without it, life on Earth would be in a lot of trouble.
Ozone is a naturally occurring molecule consisting of three oxygen atoms. The formation of this molecule is carefully balanced by a process called the Chapman cycle, in which ultraviolet light breaks the ozone down into a single oxygen atom and an oxygen molecule. Natural factors can act as catalysts for this such as volcanic activity and the Earths radiation belts.
The first observations that the ozone balance was in trouble were made in the 1980s. It was determined that the widespread use and emission of certain chemicals like chloroflourocarbons had caused severe damage to the ozone layer.
This prompted the international community to adopt the Montreal Protocol in 1987 – so far the only UN agreement ever ratified by every member state.
IR radiation has a subtly different effect on Earth and other planets. All objects emit a range of light depending on their temperature. An object at an average temperature of a million degrees would primarily emit x-rays (as some star systems do).
The sun, at an average temperature of 5,700°C, emits most strongly in visible light (specifically in yellow), while objects at room temperature emit in IR. This is why people show up clearly in an infra-red camera.
Sunlight, primarily at visible wavelengths, passes through the atmosphere and warms the Earth’s surface. To maintain thermal equilibrium, the Earth then emits light back into space, but it does so in IR. Certain molecules in the atmosphere let a large amount of visible light pass through (which is why they are invisible to the human eye) but reflect back or scatter the IR light emitted by the surface – making the surface warmer.
The chemicals involved in this process are what we know as greenhouse gases, the most commonly known is carbon dioxide, but methane and nitrous oxide are also important. What complicates the climate issue is that water vapour and ozone itself are all greenhouse gases too.
This is one of the many factors that make climate modelling a very complex topic. The greenhouse effect itself is usually described as a bad thing, but it is actually essential to life. Without any greenhouse effect, it is relatively easy to show that the Earth would be at an average temperature of -24°C, instead of our current 14°C.
Like many natural processes though, human activity has modified the greenhouse effect such that this essential feature of our planet’s habitability is now becoming dangerous. We have ample evidence that humans have increased the amount of greenhouse gases in the atmosphere, and as a result, the global average temperature.
Lessons for colonisers
The challenge for future colonists hoping to live on Mars is quite the reverse of that on Earth. Its thin atmosphere means that even though there is a large concentration of carbon dioxide, the greenhouse effect is quite weak and needs to be boosted. But a recent study has shown that even if the remaining carbon dioxide in rocks on Mars was vapourised and put into the atmosphere, there would not be enough of it to generate a sufficient greenhouse effect to make the planet warm enough to live on.
Compared with Earth, there is also very little ozone on Mars, and the thin Martian atmosphere allows much more solar-UV to reach the surface. So intense is this radiation that the top few centimetres of Martian soil are essentially sterilised once a day, with any complex molecules that might be useful for life being destroyed.
So what could we do to make the climate more similar to Earth’s? Previous ideas have included installing a giant magnet in space near Mars to protect the atmosphere and firing nuclear weapons at the surface.
A recent paper suggests we could use silica aerogel – a synthetic and ultralight material made by taking a gel and replacing the liquid component with a gas – to cover regions of the surface. This would in effect function as an artificial ozone layer, being almost transparent in visible light but blocking UV.
The use of silica aerogel would also rapidly heat up the ground underneath it to above the freezing point of water by way of an artificial greenhouse effect. Placing silica aerogel shields over ice-rich areas of the surface would generate an environment suitable for plant growth, with minimal human intervention.
This alone cannot terraform the red planet, as the Martian atmosphere is constantly being lost to the solar wind. However, it would at least provide a much less hostile environment, on a smaller scale, for future visitors. While still a difficult prospect, this is currently the most practical way of making areas of Mars a less extreme environment.
Ultimately, the success of the Montreal Protocol demonstrates both the viability of collective international action to solve an environmental problem, and that environmental modification is possible on a planetary scale in quite a short span of time. It also demonstrates clearly just how sensitive planetary environmental processes can be to artificial changes, for good or ill.
Mars: Tim Peake thinks it will only take us 50 years to live on Mars - 'I'm quite sure'
MARS will be reached within the next 50 years, European Space Agency (ESA) astronaut Tim Peake has predicted.
A manned mission to Mars was long solely the domain of science fiction, but plans to put humans on the Red Planet’s surface really are beginning to materialise. However, Tim Peak, the UK astronaut who visited the International Space Station (ISS) in 2015, believes US space agency NASA’s 2030 timetable for Mars is too ambitious.
Major Peake, 47, said: “In the next 50 years we will be celebrating humans on Mars. I am quite sure of that.
“I would be cautious about saying we will be celebrating humans on Mars in the next 20 years.“We need to have conversations about space - who owns it, who regulates it, how are we going to control the missions of the future.“Commercial companies are going to have a huge part to play in how we do that mission and when we do that mission.”
Speaking at the UK Space Conference in Newport, Major Peake said he thought it was unlikely alien life would be found on the red planet, but if even a single cell was discovered it would be “hugely significant”.
He added signs of alien life would be a “game-changer”, raising questions about the implications for other solar systems.
Major Peake also outlined the challenges facing the space industry in terms of responsibly travelling to space.
The European Space Agency astronaut explained: “Space debris has been out of control, it is now becoming under control in terms of regulation, in terms of trying to get satellite launch companies to comply with the ability to either de-orbit their satellite at the end of life, or to remove them from being a risk of space debris.
“But we can always do more – we have to clean up the problems of the past. But we are now aware of the problem.”
He outlined the necessity of cleaning outer space before a “catastrophic impact” takes out incredibly valuable space assets like telecommunications, the International Space Station and weather systems.
A European Space Agency’s satellite was only earlier this month on a collision course with the Elon Musk-owned SpaceX Starlink constellation.
This caused a satellite to performing the first-ever “collision avoidance manoeuvre”.
Major Peake said: “As space becomes more valuable to us, economically, people are waking up to the threat.”
Issues like space regulation and the management of Artificial Intelligence (AI) also need to be considered.
Mayor Peake added: “It is about having the right conversations at the right time.
“We need to be having conversations right now about artificial intelligence – how is that going to be controlled, how is that going to be managed?
“We need to have conversations about space – who owns it, who regulates it, how are we going to control the missions of the future.
“There are some really important challenges to make sure that we do things in a responsible, sustained manner.”
Life on Mars could be found within two years but world is ‘not prepared’, Nasa’s chief scientist says
Nasa is close to finding life on Mars but the world is not ready for the “revolutionary” implications of the discovery, the space agency’s chief scientist has said.
Dr Jim Green has warned that two rovers from Nasa and the European Space Agency (ESA) could find evidence of life within months of arriving on Mars in March 2021.
The ExoMars Rover, which has been dubbed “Rosalind” in memory of British chemist Rosalind Franklin, will search for extra-terrestrial life by drilling 6.5 feet down into Mars’ core to take samples.
Those samples will then be crushed up and examined for organic matter in a mobile laboratory.
Dr Green compared the potential discovery to when the astronomer Nicolaus Copernicus stated that the Earth revolves around the Sun in the 16th century.
“It will start a whole new line of thinking. I don’t think we’re prepared for the results,” he told The Sunday Telegraph. “I’ve been worried about that because I think we’re close to finding it and making some announcements.”
Nasa’s rover Mars 2020 will drill into rock formations on the planet before sending test-tubes of rock samples back to Earth – the first time material from Mars will have been brought onto this planet.
Dr Green added that the discovery of life on Mars will give scientists a new set of questions to explore.
“What happens next is a whole new set of scientific questions. Is that life like us? How are we related?” he said. “Can life move from planet-to-planet or do we have a spark and just the right environment and that spark generates life – like us or do not like us – based on the chemical environment that it is in?”
Recent research has shown that planets which were previously thought to be uninhabitable may have once had suitable conditions for life.
Earlier this year, scientists discovered that there may be a vast and active system of water running underneath the surface of Mars.
A study released this month also claimed that Venus may have been habitable for 2 to 3 billion years before its atmosphere became incredibly dense and hot about 700 million years ago.
Recent research suggests that civilisations could exist on other planets, according to Dr Green.
“There is no reason to think that there isn’t civilisations elsewhere, because we are finding exoplanets [planets outside the solar system] all over the place,” he said.
His comments came less than 24 hours before technology entrepreneur Elon Musk unveiled a SpaceX spacecraft designed to carry crew and cargo to Mars or other planets in the solar system before returning to Earth.
Mr Musk said the company’s Starship was essential for the viability of space travel by introducing a spacecraft that can be reused.
The ship is expected to take off for the first time in about two months and reach 65,000 feet before it lands back on Earth.
Elon Musk shock: SpaceX founder unleashes groundbreaking update on Mars mission rocket
ELON MUSK has revealed more groundbreaking plans for his SpaceX Starship as the billionaire takes a closer step to landing on Mars.
Elon Musk, the CEO of SpaceX, has revealed fresh details about the interstellar companies Starship prototype. The billionaire’s project intends to take people to the moon, Mars, and other distant destinations and is set to dish out new news about the Starship ahead of a big presentation over the weekend.
Today, Mr Musk will reveal the latest design of Starship and Superheavy, two ships designed to be reusable and make space travel a viable commercial option.
The presentation will happen at SpaceX’s south Texas facilities where the company is building a Starship prototype called the MK1.
SpaceX and Mr Musk hope to conduct the ships first test flight as soon as next month.
The test flight will not feature a crew and, according to Mr Musk, will reach an altitude of about 12 miles.
The entrepreneur, who founded SpaceX in 2002, has been giving eager fans, scientists and engineers snapshots of the ships construction process over the past few weeks.
Earlier this week he tweeted out a string of photos of the partly finished stainless-steel vehicle being lifted onto a transporter.
Mr Musk also addressed several questions that had been put to him by followers.
He explained that this prototype will stand at 165 feet and will weigh 1,400 tons when filled up.
But, he said he was aiming to get the ships weight down to a mere 120 tons by the time later models have been built.
He said in a tweet: "Mk1 ship is around 200 tons dry & 1400 tons wet, but aiming for 120 by Mk4 or Mk5. Total stack mass with max payload is 5000 tons.”
In another tweet, Musk revealed the number of landing legs the Mk1 will have
He wrote: "Six. Two windward, one under each fin & two leeward. Provides redundancy for landing on unimproved surfaces."
Mr Musk has said at least three of the six of his next MK1 and MK2 engines will be powered by the company’s next-generation Raptor engines.
He also posted three photos to his Twitter feed that revealed what the three engine alignment looks like.
The Raptor is SpaceX’s signature engine designed to put out a minimum of 170 tons of force for interplanetary travel.
The engine is powered by a mix of super-cooled liquid methane and liquid oxygen.
The supercooled gases, the California-based company has claimed, will give the Raptor a 10 to 20 percent boost against conventional rockets.
The company believes the engines will be reusable for up to 1,000 spaceflights.
Mr Musk, originally from South Africa, moved to Canada just before his 18th birthday to study at university against his father’s wishes.
From there, Mr Musk set up a series of tech companies and small start-ups, raising money from investors.
It culminated in his first big break, co-founding PayPal and later selling it on to eBay for $1.5billion (£1.2billion).
Mr Musk was able to invest much of the money made from the PayPal sale into his new venture, SpaceX, which has grown in as far as it now plans to be the first private space company to land on Mars.
NASA About to Send Nuclear Rockets to Moon With Ultimate Goal of Cutting Journey to Mars
NASA first floated nuclear propulsion in the '60s but ditched the idea as the Apollo era was in full swing and because of the tremendous cost of testing the reactor. However, the idea has been gaining momentum since Trump voiced the ambitious deadline for a 2024 return to the moon, and, ultimately, another long-desired target – Mars.
The story of nukes and cosmic exploration will open a new chapter just a stone's throw from the Redstone Test Stand, one of the corners of NASA's Marshall Space Flight Center, where in 1958 PGM-11 Redstone became the first to carry a nuclear warhead; three years later, a rocket carried the first American into space.
This time NASA's goal is somewhat different; it has tasked its engineers, led by physicist Bill Emrich, with building the first rocket engine powered by nuclear fission, and is expected to be twice as efficient as the chemical booster alternatives powering the lion's share of rockets today.
One would perhaps argue that space travel is dangerous in and of itself, without a necessity to worry about nuclear repercussions, but for the human missions to the Moon and Mars, already scheduled by the White House, such risks may prove unavoidable.
It may give a certain relief though, that nuclear reactors are not supposed to go off right on the launch pad, but rather up in space, after a conventional chemically-propelled rocket hoists a nuclear-powered spacecraft into orbit. The energy thrust generated by those reactors are believed to be capable of sustaining human outposts on other worlds as well as cutting the travel time to Mars by almost half.
"Many space exploration problems require that high-density power be available at all times, and there is a class of such problems for which nuclear power is the preferred—if not the only— option," Rex Geveden, a former NASA associate administrator and CEO of the power generation company BWX Technologies, told the National Space Council in August.
NASA Administrator Jim Bridenstine went still further, calling nuclear propulsion "a game-changer" and telling Vice President Mike Pence that using the said reactors provides "an amazing opportunity that the United States should take advantage of".
To reach the goal, Emrich and his team have been simulating the extreme conditions inside a nuclear rocket engine at the Marshall Space Flight Center, using massive amounts of electricity, "like in a big microwave oven," instead of triggering a costly fission reaction proper, as NASA did in the '60s.
The goal is to make sure the designed reactor would withstand its own heat and be capable of operating at extreme temperatures of around 4,000 degrees Fahrenheit.
The project that goes by the abbreviation NTREES - Nuclear Thermal Rocket Element Environmental Simulator – was eventually integrated into a more comprehensive programme to study how a nuclear engine could be integrated with the Space Launch System, NASA's next-gen rocket.
The financial aspect has also been successfully dealt with, with hefty sums earmarked for all stages of the nuclear propulsion venture: in 2017, NASA awarded BWX Technologies a three-year, $19 million contract to develop the fuel and reactor components necessary for a nuclear engine, while for the past two years, Congress has allocated a total of $225 million to NASA's budget for the purpose.
For the time being, NASA has been putting an effort into overhauling its regulations to make it possible to launch nuclear propulsion systems.
This August, a White House memo demanded that NASA develop respective safety protocols; which may see the first nuclear engine in space as early as 2024 – the deadline set earlier this year by President Trump for American astronauts to return to the Moon, decades after the successful Apollo missions, before the ultimate goal of setting foot on Mars.
NASA is not alone in its goals to reach the Moon and Mars. The European Space Agency is building a service module for Orion and NASA and has also received commitments from Canada and Japan to cooperate on lunar exploration this year.
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