Asteroids

1. If all of the asteroids were combined into a ball, they would still be much smaller than Earth's moon. If the sun was as tall as a typical front door, Earth would be the size of a nickel, the moon would be about as big as a green pea and Ceres (the largest object in the main asteroid belt) would be as small as a sesame seed.
   

   Dawn: First to orbit an asteroid

2. Most Asteroids orbit our sun, a star, in a region of space between the orbits of Mars and Jupiter known as the Asteroid Belt.
3. Days and years vary by asteroid. A day on asteroid Ida, for example, takes only 4.6 hours (the time it takes to rotate or spin once). Ida makes a complete orbit around the sun (a year in this asteroid's time) in 4.8 Earth years.
4. Asteroids are solid, rocky and irregular bodies.
5. Asteroids do not have atmospheres.
6. More than 150 asteroids are known to have a small companion moon (some have two moons). The first discovery of an asteroid-moon system was of asteroid Ida and its moon Dactyl in 1993.
7. Asteroids do not have rings.
8. More than 10 spacecraft have explored asteroids. NEAR Shoemaker even landed on an asteroid (Eros). The Dawn mission is the first mission to orbit (2011) a main belt asteroid (Vesta).
9. Asteroids cannot support life as we know it.
10. Ceres, the first and largest asteroid to be discovered (1801 by Giuseppe Piazzi) and the closest dwarf planet to the sun, encompasses over one-third of the estimated total mass of all the asteroids in the asteroid belt.

Earth's Moon

1. If the sun were as tall as a typical front door, Earth would be the size of a nickel and the moon would the size of a green pea.
2. The moon is Earth's satellite and orbits the Earth at a distance of about 384 thousand km (239 thousand miles) or 0.00257 AU.

   Twelve human beings have walked on the moon.

3. The moon makes a complete orbit around Earth in 27 Earth days and rotates or spins at that same rate, or in that same amount of time. This causes the moon to keep the same side or face towards Earth during the course of its orbit.
4. The moon is a rocky, solid-surface body, with much of its surface cratered and pitted from impacts.
5. The moon has a very thin and tenuous (weak) atmosphere, called an exosphere.
6. The moon has no moons.
7. The moon has no rings.
8. More than 100 spacecraft been launched to explore the moon. It is the only celestial a body beyond Earth that has been visited by human beings (The Apollo Program).
9. The moon's weak atmosphere and its lack of liquid water cannot support life as we know it.
10. Surface features that create the face known as the "Man in the moon" are impact basins on the moon that are filled with dark basalt rocks.

What is a Planet?

Our understanding about the universe and our place in it has changed over time. New information can cause us to rethink what we know and reevaluate how we classify objects in order to better understand them. New ideas and perspectives can come from questioning a theory or seeing where a classification breaks down.
Defining the term planet is important, because such definitions reflect our understanding of the origins, architecture, and evolution of our solar system. Over historical time, objects categorized as planets have changed. The ancient Greeks counted the Earth's moon and sun as planets along with Mercury, Venus, Mars, Jupiter, and Saturn. Earth was not considered a planet, but rather was thought to be the central object around which all the other celestial objects orbited. The first known model that placed the sun at the center of the known universe with the Earth revolving around it was presented by Aristarchus of Samos in the third century BCE, but it was not generally accepted. It wasn't until the 16th century that the idea was revived by Nicolaus Copernicus. By the 17th century, astronomers (aided by the invention of the telescope) realized that the sun was the celestial object around which all the planets - including Earth - orbit, and that the moon is not a planet, but a satellite (moon) of Earth. Uranus was added as a planet in 1781 and Neptune was discovered in 1846.
Ceres was discovered between Mars and Jupiter in 1801 and originally classified as a planet. But as many more objects were subsequently found in the same region, it was realized that Ceres was the first of a class of similar objects that were eventually termed asteroids (star-like) or minor planets.
Pluto, discovered in 1930, was identified as the ninth planet. But Pluto is much smaller than Mercury and is even smaller than some of the planetary moons. It is unlike the terrestrial planets (Mercury, Venus, Earth, Mars), or the gas giants (Jupiter, Saturn), or the ice giants (Uranus, Neptune). Charon, its huge satellite, is nearly half the size of Pluto and shares Pluto's orbit. Though Pluto kept its planetary status through the 1980s, things began to change in the 1990s with some new discoveries.
Technical advances in telescopes led to better observations and improved detection of very small, very distant objects. In the early 1990s, astronomers began finding numerous icy worlds orbiting the sun in a doughnut-shaped region called the Kuiper Belt beyond the orbit of Neptune - out in Pluto's realm. With the discovery of the Kuiper Belt and its thousands of icy bodies (known as Kuiper Belt objects, or KBOs; also called transneptunians), it was proposed that it is more useful to think of Pluto as the biggest KBO instead of a planet. Then, in 2005, a team of astronomers announced that they had found a tenth planet - it was a KBO even larger than Pluto. People began to wonder what planethood really means. Just what is a planet, anyway? Suddenly the answer to that question didn't seem so self-evident, and, as it turns out, there are plenty of disagreements about it.
The International Astronomical Union (IAU), a worldwide organization of astronomers, took on the challenge of classifying the newly found KBO (later named Eris). In 2006, the IAU passed a resolution that defined planet and established a new category, dwarf planet. Eris, Ceres, Pluto, and two more recently discovered KBOs named Haumea and Makemake, are the dwarf planets recognized by the IAU (as of July 2013). Pluto, Eris, Haumea, and Makemake are also classified as KBOs, and Ceres retains its asteroid label. There may be another 100 dwarf planets in the solar system and hundreds more in and just outside the Kuiper Belt.
Astronomers and planetary scientists did not unanimously agree with these definitions. To some it appeared that the classification scheme was designed to limit the number of planets; to others it was incomplete and the terms unclear. Some astronomers argued that location (context) is important, especially in understanding the formation and evolution of the solar system.
One idea is to simply define a planet as a natural object in space that is massive enough for gravity to make it approximately spherical. But some scientists objected that this simple definition does not take into account what degree of measurable roundness is needed for an object to be considered round. In fact, it is often difficult to accurately determine the shapes of some distant objects. Others argue that where an object is located or what it is made of do matter and there should not be a concern with dynamics; that is, whether or not an object sweeps up or scatters away its immediate neighbors, or holds them in stable orbits. The lively planethood debate continues.
As our knowledge deepens and expands, the more complex and intriguing the universe appears. Researchers have found hundreds of extrasolar planets, or exoplanets, that reside outside our solar system; there may be billions of exoplanets in the Milky Way Galaxy alone, and some may be habitable (have conditions favorable to life). Whether our definitions of planet can be applied to these newly found objects remains to be seen.

Science is a dynamic process of questioning, hypothesizing, discovering, and changing previous ideas based on what is learned. Scientific ideas are developed through reasoning and tested against observations. Scientists assess and question each other's work in a critical process called peer review.

Final Doctor Who e-book author revealed as Neil Gaiman

Author Neil Gaiman has been revealed as the final short story author of the Doctor Who stories.

The series is part of the 50th anniversary of Doctor Who, with each short story based on one of the 11 Doctors.

Nothing O'Clock will be published towards the end of this month as an e-book.

Gaiman's story focuses on actor Matt Smith's character as the most recent Doctor.

Terrify Doctor Who fans

He also revealed he wanted to tell us more about the Doctor's assistant Amy Pond, before she got married.

Neil said he also created a new villain called The Kin, which he hopes will "terrify" Doctor Who fans.

The author added: "Once I'd finished telling my story, in which I create an incredibly creepy Dr Who villain or possibly bunch of villains called The Kin, there was definitely part of me who went 'You know, wouldn't it be fun to put this on screen?'

"Wouldn't this be fun to see if I can actually make people wee themselves with terror in real life?"

Neil Gaiman is the author of several children's books such as Coraline, Fortunately The Milk and The Graveyard Book.

Other authors who contributed to the series include Malorie Blackman, Patrick Ness, and Charlie Higson.

Nothing O'Clock will be released on 21 November.

 

 

 

Is it cheating when popstars use Auto-Tune?

Gareth Malone has criticised popstars who use Auto-Tune because he says it is cheating.

The presenter of The Choir says music from popstars like Lady Gaga and Katy Perry sounds plastic because they use technology to make each note sound perfect.

He says it's unfair to other musicians like singers in choirs and classical singers who don't change their sound.

• Is it cheating to use auto-tune technology to perfect a song?
• Or do you think it is fine to use electronic equipment to make music sound better?

Of course it is cheating, but nothing surprises me about the modern music industry manufacturing process. Most of what gets churned out is rubbish anyway, but people have a choice whether to buy it or not. As long as people buy it, the industry will keep making it.

Neil, London, England

I don't think it's cheating, but it certainly isn't right! I think artists should embrace their voice and not try to change it!

Noa, New Jersey, USA

I think it isn't cheating because when artists produce a track they can use whatever effects they want to make it sound right. This could include the Auto-Tune. It's when the live performances are altered or mimed - that's when it's cheating.

Holly, Chester, England

I think Auto-Tune is okay for a CD because let's face it, who wants to hear a CD that doesn't sound good? But if they are performing, I think its best that they actually sing with their own voice!

Chey, London, England

I think it is cheating because we want to hear the real sound that projects from their voices! TV programmes like X Factor have also stopped using it because they thought it was cheating.

Niamh, Bristol, England

I don't think it's a problem using Auto-Tune, but it is a problem if a singer can only sing with Auto-Tune. If they can't sing very well live without lip-syncing then they really should not be a musician. I don't think Lady Gaga and Katy Perry are cheating as long as they can sing well live which I think they can.

Liam, Cambridgeshire, England

I think that it is cheating because they should become famous for what they sound like, not what they want their voices to sound like.

Emma, Dublin, Ireland

If all they write their songs as well as singing them, cheating is excusable. But if they're just paid to sing, you would at least expect them to sing it properly.

Elly, Bradford, England

I do think that it is cheating. I believe that you should sing and record your natural voice.

Christian, Bromsgrove, England

I don't think I would call it "cheating". Artists like Lady Gaga use Auto-Tune to create an effect of a modern, electronic sound - and it's proven that she can sing without it through her many live performances. I would say that it's more of a creative choice, and I think artists can choose to use or not to use it depending on the sound/genre they're aiming towards.

Nicholai, Mandaluyong City, Philippines

It kind of is because you are not hearing their actual voice so people don't really know what the singer's voice is like really. The singer could be really bad but Auto-Tune might make their voice sound fabulous!

Kim, Edinburgh, Scotland

It is cheating because suppose at the teen awards and a singer that used Auto-Tune won, but a singer who did not use Auto-Tune didn't and was a better singer... that's unfair on all singers.

Bryanna, India

It is, because it is like changing their voice meaning it's not them.

Ash, West Yorkshire, England

I think it's fine. People want the best of the best, so if that is required use it. There's no one saying you can't so you may as well put it to good use.

Ellie, Retford, England

I don't think it's a problem using auto-tune. But it is a problem if a singer can only sing with auto-tune. If they can't sing very well live without lip syncing then they really should not be a musician. I don't think Lady Gaga & Katy Perry are cheating as long as they can sing well live which I think they can.

Liam, Cambridgeshire, England

I think that it is cheating because they should become famous for what they sound like, not what they want their voices to sound like.

Emma, Dublin, Ireland

Using distortion in a song to improve instrument sounds, I think, is fine, but vocalists need to be able to sing themselves, otherwise, they're not really musicians.

RA, Birmingham, England

If they all write their songs as well as singing them, cheating is excusable. But if they're just paid to sing, you would at least expect them to sing it properly.

Elly, Bradford, England

I do think that it is cheating. I believe that you should sing and record your natural voice.

Christian, Bromsgrove, England

I think it is cheating as singers like Elvis Presley and Pavarotti used their natural voice and sounded really good if you listen to their work.

Samuella, Buckinghamshire

I think it is cheating as they were hired by a music company for their voice, why attempt improve what is already fantastic? I even hear auto-tune that is absolutely horrible sometimes, I prefer the natural voice better.

Charlie, Devon, England

 

 

 

Book dominoes world record set

A book group in Belgium is celebrating today after breaking a world record.

They spent a whole night setting up 4,845 books in a 600-metre domino chain before knocking them all down.

The books all had to fall in the right order for them to win the world record - and they did it!

The previous winners, from South Africa, held the title for a chain that had 2,850 books in it.

The Belgian group decided to have another go straight away using 5,500 books, but that one didn't work.

Never mind, they are still the world record holders.

Katy Perry overtakes Justin Bieber on Twitter followers

Katy Perry has overtaken Justin Bieber as the most followed person on Twitter.

The latest figures show the US singer has more than 46 million followers, thousands more than the Biebster.

Shea Bennett from the All Twitter news blog said Perry was now likely to be the first to get to 50 million.

She said: "Bieber has been quite active on his profile as he's on tour in Brazil, but Perry hasn't tweeted since October, so expect a little more action once she gets back on the train."

Justin Bieber took Twitter's top spot from Lady Gaga in January.

The Canadian star passed the 40 million followers mark in June.

Earlier this year a report suggested that around 50% of Bieber's followers could be fake.