Water found for first time on 'potentially habitable' planet

Astronomers have for the first time discovered water in the atmosphere of a planet orbiting within the habitable zone of a distant star.

The finding makes the world - which is called K2-18b - a plausible candidate in the search for alien life.

 Within 10 years, new space telescopes might be able to determine whether K2-18b's atmosphere contains gases that could be produced by living organisms.

 Details were published in the scientific journalNature Astronomy .

 The lead scientist, Prof Giovanna Tinetti of University College London (UCL), described the discovery as "mind blowing". "This is the first time that we have detected water on a planet in the habitable zone around a star where the temperature is potentially compatible with the presence of life," she said.

 The habitable zone is the region around a star where temperatures are considered sufficiently benign for water to exist in liquid form on the surface of a planet. The new planet is just over twice the size of Earth - in a planet category known as a "super Earth" - and has a temperature cool enough to have liquid water, between zero and 40C. K2-18b is 111 light-years - about 650 million million miles - from Earth,

too far to send a probe. So the only option is to wait for the next generation of space telescopes to be launched in the 2020s and to look for gases in the planet's atmosphere that could only be produced by living organisms.

 What is an exoplanet?

Planets beyond our Solar System are called exoplanets

1. The first exoplanet was discovered in 1992, orbiting a pulsar (a neutron star that emits electromagnetic radiation)

2. More than 4,000 have been detected to date using several techniques

3. Many of these worlds are large planets believed to resemble Jupiter or Neptune

4. Many giant planets have been found orbiting very close to their stars


The team behind the discovery looked through the planets discovered by the Hubble Space Telescope between 2016 and 2017.

The researchers determined some of the chemicals in their atmosphere by studying the changes to the starlight as the planets orbited their suns.

The light filtered through the planets' atmospheres was subtly altered by the composition of the atmosphere.

 Only K2-18b revealed the molecular signature of water, which is a vital ingredient for life on Earth. Dr Angelos Tsiaras, a member of the UCL team, said that finding water in the atmosphere of a "potentially habitable exoplanet was incredibly exciting". Other astronomers, however, dispute the claim that the planet is potentially habitable.

One analysis indicates that planets that are 1.5 times the mass of the Earth are unlikely to have a rocky surface. There is also concern that K2-18b's size and gravity would make it difficult for the world to support life.

 Other critics suggest that the planet should not be classified as a super-Earth, but as a mini Neptune instead. This is a class of planet that is typically more massive than a super-Earth (it includes worlds that are up to 10 times the mass of our own planet).

Prof Tinetti, however, maintains her view that the new world is potentially habitable. She said it had a mean density that's comparable to that of Mars (which is composed of silicates) and Jupiter's moon Europa, and much higher than Neptune's. "K2-18b cannot be classified as a mini-Neptune,

it is more likely to be a planet with an interior of rock and ices. These types of planets, [are] sometimes called 'ocean planets'," she told BBC News. "Now, whether this planet really has an ocean at the surface or rock,

we cannot tell with current observations, but having water in the atmosphere is a good start." But it is a view that Dr Laura Kreidberg, of the Centre for Astrophysics at Harvard University does not agree with.

 
The interior of the planet is much more like Neptune. Pressure and temperature increase with depth, so that before a rocky surface is reached, it is too hot and too high-pressure for complex molecules like DNA or any of the other building blocks of life to form," she told BBC News. Prof David Charbonneau, also from Harvard University, said the fact that K2-18b's atmosphere was detected was proof in itself that it could not support life. "If the planet had a thin secondary atmosphere similar to Earth it would be so thin that Hubble couldn't detect it."

  Another issue is that astronomers can't agree what conditions are needed for habitability. We only have the Earth to go on but life may also be possible on other types of worlds

 It is likely to require a survey of the chemical composition of, perhaps, hundreds of worlds and an understanding of how they are created and evolve, according to Prof Tinetti.

 "The Earth really stands out in our own Solar System. It has oxygen, water and ozone. But if we find all that around a planet around a distant star we have to be cautious about saying that it supports life," she said.

 "This is why we need to understand not just a handful of planets in the galaxy but hundreds of them. And what we hope is that the habitable planets will stand out,

that we will see a big difference between the planets that are habitable and the ones that are not."

The surprising use of space technology on earth

When NASA was formed in 1958 its main objective was to put an American on the moon before the Russians got there.

The Space Race and later missions required massive innovation Many of those scientific and technological breakthroughs had an impact far beyond the space program. Everyday objects we now take for granted were invented as part of NASA’s mission to explore space.

 Some of the best are being showcased on NASA’s new interactive web features, NASA City and NASA @ Home.

  1. Artificial Limbs

Many of the parts used in modern artificial limbs were developed for space vehicles.

Diamond coatings make joints last longer and special foams make prosthetics more comfortable. Advanced robotics make artificial limbs operate more like the real thing.

2. Cardiac Implants

Around 80 British patients a year are fitted with a heart-implant called a ventricular assist device (VAD) These are used to keep blood flowing around the heart, when the muscle is no longer capable, before a donor is found.

 A product of collaboration between NASA, MicroMed Technology Inc and scientists; the VAD is small, effective and life-saving.

  3. Tyres

NASA partnered with a chemical company to make a new material for parachute cords on Mars landers. It was stronger than steel and good at absorbing shocks.

Tyre manufacturers developed the material further. It improved the tread life of conventional tyres by more than 100,000 miles.

4. Better baby milk

NASA scientists developed an additive from algae containing nutrients found in human milk.

The additive is believed to help with mental and visual development. This enriched ingredient can now be found in 90% of commercially available baby formula in the United States.

5. Temper Foam mattresses

Originally developed to improve crash protection, temper foam has since been incorporated into a host of widely used products.

It can be found in mattresses and pillows. It’s also used in protective sports equipment, amusement park rides and furniture.

6. Computer technology

From real-time weather visualization and forecasting to high-resolution 3D maps of the Moon and Mars,

NASA has always been at the forefront of computer technology advancement. To this day, NASA continues to develop and collaborate on improving software for more widespread use on Earth.

2030s, we'll be ready to start sending people to Mars

In 2015, NASA released a document that described how we get from where we are today to boots on Mars.

 This involves continuing our research on the International Space Station (ISS), then moving humans beyond low-Earth orbit to the proving ground - the region near the moon where we can push the limits of our capabilities in a place where we can safely return astronauts home in a few days.

 We will continue to robotically explore Mars – as we are currently doing as an international community with numerous spacecraft – from NASA’s Curiosity rover to India’s Mars Orbiter mission. We will use these and future missions to Mars to reduce the risks of landing humans on Mars,

from better understanding the structure of Mars’ atmosphere to its potential for providing local resources for future explorers. By the 2030s, we will be ready to move humans toward the Red Planet.

  Private sector partnerships are critical to enable us as a global society to explore Mars. NASA has been working on this by turning over to the private sector some work that we no longer need to keep as government-only functions, like launching cargo to the ISS, and soon commercial companies will be shuttling humans to the space station.

 We also are testing new technologies with private companies on the ISS, such as 3D printers that could make space exploration more sustainable. In addition to exploration technology development and demonstrations on the ISS, we also are doing critical research to ensure that we can keep humans healthy for periods of time in space, mitigating health risks such as bone density loss and muscle atrophy.

Why send people to Mars?

Some might wonder about why sending humans beyond low-Earth orbit to Mars is important, and whether it is worth the cost. Scientifically, Mars is our destination because scientists have determined that Mars is the most likely place to find evidence of life beyond Earth. Water, which is critical to life, was stable on the surface of Mars for around a billion years. Based on what we know about the evolution of life on Earth, life is likely to have arisen on Mars.

In that time period, life may not have gotten very complex, so it will likely take astrobiologists and geologists on the surface of Mars to find evidence of ancient microbial life. The evidence of liquid water on the surface of Mars also makes scientists wonder if life could have persisted on Mars, moving underground as conditions became increasingly inhospitable at the surface.  

India launched 104 satellites in a single mission

India successfully launched 104 satellites in a single mission on Wednesday, setting what its space agency says is a world record of launching the most satellites at one go.

 Of the 104, 101 are foreign satellites to serve international customers as the South Asian nation seeks a bigger share of the $300 billion global space industry. "

This is a great moment for each and everyone of us. Today we have created history," said project director B. Jayakumar. Prime Minister Narendra Modi tweeted his congratulations on the launch conducted by the state-run Indian Space Research Organisation (ISRO) that went off smoothly and was carried live on national TV news channels.

  This remarkable feat by ISRO is yet another proud moment for our space scientific community and the nation," he said. "India salutes our scientists."

 Modi is bullish on India's space programme and has repeatedly praised the efforts of scientists who three years ago pulled off a low-cost mission to send a probe to orbit Mars that succeeded at the first attempt. ISRO's low prices attracted international customers to launch 75 satellites last year from Sriharikota in the southern state of Andhra Pradesh.

 The launch of PSLV-C37 in a single payload, including the Cartosat-2 series and 103 co-passenger satellites, together weighed over 650 kg (1,433 lb). Out of 101 nano satellites, 96 were from the United States and one each from Israel, Kazakhstan, the Netherlands, Switzerland and the United Arab Emirates.