Do the preparation task first. Then read the text and do the exercises.
A new study published in the journal Science shows definitive evidence of organic matter on the surface of Mars. The data was collected by NASA's nuclear-powered rover Curiosity. It confirms earlier findings that the Red Planet once contained carbon-based compounds. These compounds – also called organic molecules – are essential ingredients for life as scientists understand it.
The organic molecules were found in Mars's Gale Crater, a large area that may have been a watery lake over three billion years ago. The rover encountered traces of the molecule in rocks extracted from the area. The rocks also contain sulfur, which scientists speculate helped preserve the organics even when the rocks were exposed to the harsh radiation on the surface of the planet.
Scientists are quick to state that the presence of these organic molecules is not sufficient evidence for ancient life on Mars, as the molecules could have been formed by non-living processes. But it's still one of the most astonishing discoveries, which could lead to future revelations. Especially when one considers the other startling find that Curiosity uncovered around five years ago.
The rover analyses the air around it periodically, and in 2014 it found the air contained another of the most basic organic molecules and a key ingredient of natural gas: methane. One of the characteristics of methane is that it only survives a few hundred years. This means that something, somewhere on Mars, is replenishing the supply. According to NASA, Mars emits thousands of tons of methane at a time. The level of methane rises and falls at seasonal intervals in the year, almost as if the planet is breathing it.
NASA suspects the methane comes from deep under the surface of the planet. The variations in temperature on the surface of Mars cause the molecule to flow upwards at higher or lower levels. For example, in the Martian winter the gas could get trapped in underground icy crystals. These crystals, called clathrates, melt in the summer and release the gas. However, the source of the methane is still a complete mystery.
The world of astrobiology considers both of these studies as historical milestones. According to this information, Mars is not a dead planet. On the contrary, it is quite active and may be changing and becoming more habitable.
Of course, this means further research is necessary. Scientists say they need to send new equipment to Mars, equipment that can measure the air and soil with more precision. There are already missions underway. The European Space Agency's ExoMars ship lands in 2020 and will be able to drill into the ground on Mars to analyse what it finds. Additionally, NASA is sending another Mars Rover in the same year to collect samples of Martian soil and return them to Earth.
The possibility of life on Mars has fascinated humans for generations. It has been the subject of endless science-fiction novels and films. Are we alone in the universe or have there been other life forms within our Solar System? If the current missions to the Red Planet continue, it looks as if we may discover the answer very soon.
There are many different ways you could do this, and I'd encourage you to experiment with different methods to see which work best for you. But for a start I'd recommend first identifying some words and phrases that you'd like to use more. You could find these by listening to what other people say or reading what they've written -- listen or look for words and phrases that impress you or that you think would be useful.
Make a list of 6–10 such words and phrases and, if possible, write out the sentences you heard or saw them in. You could then look them up in a dictionary to see how they are used in other contexts and thus get a better sense for what they mean and how they are used. A collocations dictionary could be particularly useful for this.
Then give yourself a week or so to try and use these phrases in your speaking and writing. If you can't find a situation to use them in your natural life, you can imagine one and speak to yourself or write about it.
Then repeat this process with a new set of words. As you do this, be sure to revise the words and phrases in your past lists so that you have a better chance of remembering them.
I hope this helps you. We'd love to hear how you get on with this.
All the best,
The LearnEnglish Team
I'm afraid that neither of your suggestions is correct. 'A new study published' is a reduced form of 'A new study that was published' and adding 'is' would conflict with the verb 'shows' as the sentence is written.
As for the second phrase, 'it' refers to the rover and 'that' is left out: the rover found that the air contained methane.
Hope that helps you make sense of these two sentences. By the way, we check our articles multiple times before publishing them, so usually they are correct. Occasionally a mistake does get through, but for the most part you can trust that they are correct!
All the best,
The LearnEnglish Team
It's not a silly question at all! Both finding and find can be used as nouns, but there is a difference. Finding is used for the results of experiments and surveys, while find is used for physical discoveries. Thus, a medical researcher reports some interesting findings, but an archeologist announces an exciting find.
In the context of the text, find is used because the rover discovered something in the air with a physical existence: methane molecules. Of course, since these were also discovered through running tests, you could use finding here as well.
The LearnEnglish Team