Sam has worked as a forensic scientist as well as for the British government, and has degrees in both archaeology and osteoarchaeology. She has 2 children, is passionate about science, reading, history and music, and loves dyeing her hair bright colours!
Sam blogs about all kinds of science at www.samanthagouldson.com.
Autumn is a season of change; the weather gets colder, there’s less daylight and leaves change colour and fall from plants. But why does this happen?
Why Do Plants Have Leaves?
Leaves contain a chemical called chlorophyll (pronounced KLO-ro-fil), which as well as giving them their lovely green colour also helps create food for the plant. The leaves act like tiny solar panels, and use the sun’s energy to convert water (from the ground) and a gas called carbon dioxide (from the air) into sugar and oxygen. This process is called photosynthesis (pronounced foto-SIN-theh-sis), and the sugar is what the plant lives on.
This October Earth will be passing through the tail of Halley’s comet, which will mean a shower of meteors flashing across the night sky. Our science editor Sam Gouldson explains.
What is Halley’s Comet?
A comet is a lump of rocky particles, ice and dust all bound together like a dirty snowball. When the comet nears a star, its surface transforms from a solid to a gas. The star’s light shines through these gases and makes them visible to observers as a fuzzy cloud around the comet’s centre, and a tail streaming out behind.
Although beaches are fun places they can also be dangerous, and you may have heard some stories in the news lately about people getting into difficulties when they’re in or by the sea. Our science editor Sam Gouldson, who lives on the Sussex coast, shares her tips for beach safety.
Beaches in the UK use a flag system to inform you of possible hazards. If there are red and yellow flags this means that there are lifeguards in that area and that it’s safe to swim.
A black and white chequered flag means that the area is for people using paddleboards, surfboards and kayaks, and that you should not swim there.
A red flag means that the area is dangerous and you should not go into the water for any reason. There may also be information boards and signs at the beach, and you should read these thoroughly.
Stay With Your Group
If you stick with your family or friends you can all keep an eye on each other. Find somewhere distinctive to use as a base while you’re at the beach and agree where you’ll meet up if you get separated.
If there are younger children in your group make sure they’re with a responsible adult or older teen. Some beaches have a wristband scheme so that children can be easily identified and their group members contacted if they wander off; if the beach you’re visiting has one of these schemes, take part.
Learn About the Sea
Different beaches have different conditions. The tide can come in much faster at one beach than at another, and you should always keep an eye on the water and which direction it’s flowing in. You can look up tide tables online so that you’re aware of when the tide is likely to turn and don’t get cut off from the shore.
Some beaches have dangerous features called rip tides, which are strong currents that can quickly sweep you out to sea without warning. Always check with the beach’s lifeguards if there are any areas that you should avoid – many beaches have a noticeboard to inform visitors about the current conditions.
Waves can also be dangerous, depending on how fast the water is moving and how steeply the beach shelves. Some beaches will have sharp rocks or other hazards that may not be clearly visible from the shore. Again, check the lifeguard’s advice before you go into the water.
If the weather is cool, consider wearing a protective suit to keep you warm in the water, as cold water shock can affect your breathing, blood pressure and heart rate.
Be Careful When Using Inflatables
Inflatable toys and beds are designed to be used in swimming pools, not on open water. But if you do use them make sure there is an adult with you and that you’re in the lifeguarded area between the red and yellow flags.
You should stay near the shore and never use inflatables when there are big waves or an windsock is flying; these are signs that the wind is too strong.
Know What to Do If You Get Into Trouble
If you find yourself in difficulties, stay calm. If the water is shallow enough for you to stand, wade through the water instead of trying to swim in it. Raise at least one hand in the air and shout loudly and clearly for help, and don’t try to swim against the tide because you’ll just tire yourself out.
If you have a board or an inflatable hold onto it; not only will it help you stay afloat it will also make you easier for rescuers to spot.
If you see someone who is in trouble in the water, stay calm. Alert the lifeguards, or if you can’t see them call the emergency services on 999 (in the UK) or 112 (anywhere in Europe).
Stay Safe in the Sun
Although the sea can be dangerous, so too can the sun. Always use sunscreen with a sun protection factor (SPF) of at least 30, and re-apply frequently.
Keep your head and shoulders covered, wear sunglasses to protect your eyes and stay in the shade at the hottest part of the day (usually between 11am and 3pm).
There has been a lot of excitement about the Juno probe this week, but what is it and what is its mission?
What is Juno?
Juno is a spacecraft designed and operated by NASA, the US space agency. It was launched from Cape Canaveral on the 5th August 2011 and has taken almost 5 years to travel the 716 million kilometres to Jupiter, the largest planet in our solar system. Juno is 3.5 metres in height, and when its solar arrays are extended it’s more than 20 metres across. These arrays are covered in more than 18,500 solar cells, which allows Juno to operate even when it’s at such a great distance from the Sun.
Why is it called Juno?
In Roman mythology Juno was the Queen of the gods. She was married to the king, Jupiter, who wasn’t always well-behaved. Juno had to peer through the clouds to discover what he was up to; the spacecraft is called Juno because it will be looking beneath the clouds that cover the surface of the planet Jupiter.
Aboard the Juno craft are 3 models of Lego minifigures: Jupiter, Juno and Galileo, who discovered in 1610 that Jupiter had moons.
From left to right: Galileo, Juno and Jupiter. (Image: NASA/JPL-Caltech/LEGO).
What is it looking for?
Jupiter is enormous; it’s two and a half times larger than all the other planets in our solar system combined. It’s made entirely of gases and is believed to have no solid surface. The planet rotates at an immense speed, completing one rotation every ten hours, and telescopes have shown us that it has a cloudy atmosphere with colourful spots and stripes. The largest of these, known as the Great Red Spot, is a storm that is several times the size of Earth and has been raging for more than 300 years.
Jupiter. The Great Red Spot is clearly visible. (Image: NASA).
This mission is the first time that humans will be able to glimpse what lies beneath Jupiter’s cloudy atmosphere. The main objective is to understand how the planet formed and evolved, which will give us more information about the formation of gas giants as well as the rest of the solar system. Juno will also measure the quantities of water and ammonia within the atmosphere, examine the magnetic field that surrounds the planet, observe any polar auroras and measure the gravity to see whether a solid core may exist after all.
One of the best known landmarks in Bristol, UK, the Clifton suspension bridge first opened in 1864. It was built by the famous British engineer Isambard Kingdom Brunel, but it has recently become public knowledge that it was designed by a woman. Our science editor Sam Gouldson explains who she was and why her work isn’t more widely known.
Who really designed the bridge?
The Clifton suspension bridge was designed by a woman called Sarah Guppy. She was born Sarah Beach in 1770, but when she married her husband Samuel Guppy she took his name. She was one of the great British inventors of her time and the bridge isn’t the only thing she came up with.
What else did she design?
The invention that earned Sarah the most money was her device to prevent barnacles forming on the hulls of ships. Without barnacles the ships would be able to cut better through water and travel more quickly, and the Royal Navy paid her £40,000 for it. That may not sound like much for such a valuable design, but today it would be more than £2.3 million. Her other inventions included a kettle that not only boiled water for tea but could cook an egg and keep toast warm, a candle holder that could keep candles alight for longer and a way of treating boats so that they were more watertight. She also came up with the idea of planting willow and poplar trees on the embankments of new railways, to hold the earth together and prevent landslides.
Why isn’t she more famous?
Sarah lived during the Georgian and Victorian eras. In those times married women weren’t allowed to own property in their own name, and intellectual property such as Sarah’s inventions were no different. Her husband had to file the patents on her behalf, as the property of the Guppy family. The patent for her method of piling bridge foundations in order to create a new kind of bridge was filed in 1811, but she refused to charge others to use the idea because she felt it was for the benefit of the public. Thomas Telford, a civil engineer, used her design to build the Menai bridge in 1826, and when the competition to design the Clifton bridge was announced Sarah gave her work to Brunel. When she wrote to him to suggest the use of willow and poplar trees to reinforce railway embankments, she explained that she didn’t want the credit for her idea because she felt that women “must not be boastful”.