The sister world is only about one-and-a-half times as big as our home world (Artist’s impression: NASA/JPL-Caltech/T. Pyle)

In so many words is where we retell our stories on space and physics using only the 1000 commonest words in English

One of the most important questions student-people ask is whether we are alone in the All-There-Is. To find life somewhere else out there would change the way we think about us.

To answer this question, student-people first need to find another world where life could grow. After looking at all the worlds going around our sun, as far as we can tell our home world is the only one that is good enough for life. So we have to look further away.

We have found hundreds and hundreds of worlds going around far-away stars. But most of these far-away worlds are much bigger than our home world, and much closer to their stars – those are the ones that are easier to spot.

But now, student-people have found a world that is not too different from our own. This sister world is only about one-and-a-half times as big as our home world, and it goes around its star in about the same time it takes us to go around the sun.

The sister world is not exactly around the corner: just sending a letter there saying “Hello!” would take over ten-hundred years, even if the letter was made of light, the fastest thing there is.

Student-people believe that the sister world could be made of rock, just like our home world, and perhaps might even have air. But the star it goes around is much older than our sun, which makes it hotter. So the sister world might look a bit like what our home world will be like many years down the line: too hot for us, and with no water.

This reminds us just how hard it is to find a good world to live on. But with more time and work, the student-people hope to spot a world that is just like ours.

Soon, we might feel less alone in the All-There-Is.

Glossary:
All-There-Is: universe
student-people: scientists
sister world: Kepler 452b
home world: Earth

The Hell-God World is more beautiful than we thought (Image: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)

All the team jumped up and down, hugged each other and screamed, happy: after a long trip that started many years ago, their space-car had finally reached the farthest world going around the sun: the Hell-God World.

There are three times three worlds going around the sun. Our Home World is one of them, and it is number three. The others are all called after old gods, and the most far-away one is the Hell-God World.

The Hell-God World is so far from the sun that four of its years last ten hundred of ours. Student-people decided a few years ago that the Hell-God World is actually too small to be a world like all the others. Now it is called a minute world.

But no one had seen what it really looks like. The Hell-God World is hard to see from our Home World, even with a big seer. This is why the student-people had sent a space-car to take a closer look. They wanted to understand how the Hell-God is put together, what it is made of, and what its air is like.

The space-car flew silent for three times three years. When it finally arrived, it was going so fast that it would go around our whole Home World in less than an hour. The space-car had just three minutes to take pictures of the Hell-God World from very close by. After then, it continued to fly towards the stars, and it started to send back home what it had learned.

The amazing pictures taken by the space-car showed that there is ice on the Hell-God World. But this is not water ice: rather, it is made of the same stuff that burns in a blue fire in our kitchen to make our food hot.

The space-car also looked at the Hell-God World’s sister, a smaller world that goes around the Hell-God World. Rocks on the Hell-God World’s sister seem much older than on the Hell-God World. This led student-people to think that rocks on the Hell-God World change over time, perhaps because of its air.

Over the coming months, the student-people will get many more pictures from their space-car. Little by little, they will understand the Hell-God World better and better.

The minute world has many more big stories to tell.

Glossary
Hell-God World: Pluto
Hell-God World’s sister: Charon
space-car: New Horizon spacecraft
Home World: Earth
big seer: large telescope
minute world: minor planet
student-people: scientists

Make yourself at home (Image: David Howells/Corbis)

In so many words is where we retell our stories on space and physics using only the 1000 commonest words in English

Finding any type of life outside our Home World would change the way we see our place in the All-There-Is. One of the reasons for sending space-people to the Red World is to look for small-life there. Student-people believe that some strange small-life might be found under the ground, or was there in the past.

But small-life from our Home World could ride along in the space-car and, once on the Red World, be easily confused for Red-World-grown small-life. This is why lots of time and money are spent to kill all small-life from space-cars before they are sent to the Red World. If one day we’ll send space-people, they will carry lots of small-life with them: on their skin, in their stomach and under their feet.

But now student-people have found that we might not need to go through the trouble of killing all the small-life, which would save a great deal of money.

They drove a car all the way to the top end of our world, where everything is covered by ice water and it’s so cold that no small-life can live there – a bit like on the Red World. This is a place where Space-people who hope one day to go to the Red World spend time training for the trip.

The student-people checked whether small-life from inside the car could be found outside, to see how far it could escape on its own. Then steps away from their car, they found almost none.

This shows that the chance of Home World small-life taking over the Red World is small, even if it were to ride along our space-cars. What is more, any left-over small-life escaping from our space-cars on the Red World would quickly die because of killer light from the sun.

When space-people get to the Red World, they might not need to pause at the door of their space-car to wipe their feet before taking that last step out.

Glossary:
Red World: Mars
Home World: Earth
small-life: microbes
space-people: astronauts
student-people: scientists

What causes the excess emissions of gamma rays seen at the Milky Way’s centre? (Image: NASA/T. LINDEN, UNIVERSITY OF CHICAGO/SPL)

Dark matter is keeping to the shadows. A potential sign of the mysterious stuff may actually be due to the husks of dead stars.

For decades astronomers have suspected the existence of a form of matter, called dark matter, that doesn’t emit or absorb visible light and is five times more abundant in the cosmos than normal matter.

Since 2009, data from NASA’s Fermi satellite have shown an unexplained excess of gamma rays at the centre of the Milky Way that look strikingly like dark matter particles annihilating each other and emitting high-energy light in the process.

But two independent teams have now concluded that the signals are probably contaminated by thousands of previously undiscovered pulsars, a type of rotating stellar corpse. This is the first indication that so many pulsars are there – and it could kill the dark matter interpretation.

“The recent findings show that some of the astrophysical explanations were dismissed prematurely,” says at the University of Amsterdam in the Netherlands. “This is good news for pulsar people, but bad news for people that were counting on a dark matter signal.”

helped build the case for a dark matter origin of the signal, but she concedes that the new results have “substantially” reduced that explanation’s plausibility. “I would now assign it 20:1 odds,” she said.

But the hunt isn’t over: the Fermi satellite is expected to release new data soon that will allow scientists to refine their tests further. Expect new twists.

Journal reference: ;

In so many words is where we retell our stories on space and physics using only the 1000 commonest words in English.

If you want to go to another world, one of the biggest problems is how to power your space-car. Normal space-cars today throw out fire from their back, and that pushes them forward. But this is not a very good way of getting to very far-away worlds: you’d have to fill up your space-car with a lot of stuff to burn, and this would be too heavy to carry.

A better idea is to do as people did in old times when they crossed big blue bodies of water: catch the wind – but this time in space. Light from the sun works like a space-wind that can push your space-car forward into deep space if you have a big enough wind-catcher.

Now student-people think they might have found an even better way. They took a new type of finer-than-paper stuff, made by tiny bits of that clear rock that is on the ring a man gives to his girlfriend when he wants to marry her. The finer-than-paper stuff is very light and very strong, and has many interesting uses. The student-people who first made it were asked to the party set up by Mr Nobel a few years ago – a fine party only student-people who did something really amazing can go to.

Student-people found that if you cut up the finer-than-paper stuff in bits and then flash light from the sun on them, the bits will jump forward much further than you would expect. It is not clear yet why exactly this works so well. But the great thing is that the push you get this way from the sun’s light would be many tens of times larger than by using a space wind-catcher.

One day perhaps space-cars covered in finer-than-paper bits may give us the means of reaching the stars.

Glossary:
Student-people: scientists
Space-car: rocket
Finer-than-paper stuff: graphene