Samantha Rolfe

Astronomy and Astrobiology

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Navigating ants, hotting up in 2016 and lunar eclipse: Science Feature with Sam Rolfe 30-01-2017

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Ants use Sun and step count for navigation

Ants brains are smaller than a pin head but they can navigate to a greater extent than many other larger species. They have been found to use the Sun and visual cues in their environment. They have to carry large pieces of food back to their nests so have to rotate their body position independently of their direction of travel to achieve this. If the Sun was obscured they went in the wrong direction. If they were moving backwards, they stop, drop the food, and double check their direction before carrying on.

Understanding how ants navigate informs robotic research including designing algorithms to guide robots, including self-driving cars.

Ants have also been found to count their steps. A pile of food was placed at a certain distance from their nest, once they had been to the food pile they had small stilts made of pig bristles attached to their legs and rather than making it back to their nests some went up to 50% further than they were supposed to. However, they soon adapted to the additions, and by the next day they could find their way to and from the food pile without difficulty.


2016 hottest year since records began

Despite contributions from a known climate cycle phenomena called El Niño, which among other impacts on weather patterns influences increases the global temperature, 2016 was the hottest year on record. This adds to the growing and substantial amount of evidence of man-made climate change due to the release of CO2 and other greenhouse gases into the atmosphere.

97% of climate scientists agree that it is a man-made contribution that is causing a year on year trend of increasing global temperatures. It is real, it is a fact, it is not a bargaining chip for businesses to make money or for political gain, it is not in the realm of opinion. Every individual should take action in our effort to reduce the man-made impact, it is not just a problem for government, councils or businesses.

There are many pages of information on how you can reduce your personal impact on climate change, but here are a few things to put into action if you don’t already.

  1. Recycle or re-use. Make a conscious effort to buy products with a recyclable packaging or choose products that have little to no packaging. Recycling is being made easier and easier for us, there is no excuse for recycling not to be a daily habit. Dispose of items like electronics and batteries responsibly.
  2. Reduce your energy use. For example, turn lights off when you leave a room, turn off computers, televisions and monitors not just on standby, replace bulbs and appliances with more modern energy efficient equivalents.
  3. Think about transport. Walk, bike or use public transport whenever possible. Think about your car, could you replace it with a more energy efficient model. Or at least ensure your tyres are correctly pressured and you aren’t carrying a lot of weight, empty the junk out!
    3a. If you aren’t driving, please don’t sit in your car with the engine idling, if you are unlikely to be moving within 30 seconds, turn your engine off! Save petrol and hence money and reduce the release of car fumes into the atmosphere.
  4. Insulate your home and reduce your water use.


Scientist of the Month

John Hunter (1728 – 1793)

Thought of as the founder of scientific surgery. He made many contributions to medicine including:

A study of inflammation, teeth and bone growth, gunshot wounds, understanding the nature of the digestion and the first complete study of the development of a child, proving that the maternal and foetal blood supplies are separate.

However, to advance his knowledge of the human body he used to pay grave-robbers to bring him cadavers to practise surgical procedures.

In his later career, he prepared over 14,000 samples from 500 species, which were donated to a museum, which now reside at the Hunterian Museum in the Royal College of Surgeons in London.


Night Sky This Month

The evenings are dark for the next week or so as the Moon heads in and out of New Moon phase, so good viewing for other objects, especially deep sky objects.

There is a penumbral lunar eclipse on the 10/11th Feb, starting at 22:34 10th Feb and the time of greatest eclipse is at 00:45 on 11th Feb finishing at 02:53. The Moon will get darker(, but as it is not a total lunar eclipse the face will not turn a red colour which is due to when the Moon is in the full shadow of the Earth the Sun’s rays are refracted through the Earth’s atmosphere).

In the early evening the very bright object in the West is Venus, visible for the next few weeks – it too has phases, which are visible through binoculars or small telescopes. It will become more and more crescent-like over the next month.


Twitter: @smrolfe

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West Herts Drive Time Science Correspondent 23/03/2015 – Night Sky This Month – March/April

4th April Full Moon (Total Lunar Eclipse – Eastern Asia, Australia, Pacific Ocean, Western Americas. In Britain there will be one on 28th Sept 2015)

13th to 18th April – International Dark Sky Week, join in by reducing light pollution (turn off outside lights where possible) and enjoy dark skies.

22nd/23rd April Lyrids Meteor Shower peak. Moon sets shortly after midnight allowing for a dark sky to view the show, approximately 20 meteors per hour. Produced by debris left behind by comet C/1861 G1 Thatcher.

25th April International Astronomy Day


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West Herts Drive Time Science Correspondent 23/03/2015 – News – Differences isolated for the first time between autistic and non-autistic brains

Differences isolated for the first time between autistic and non-autistic brains

Following the development of a new method for analysis MRI scans of the brain, scientists in the Dept. of Computer Science at the University of Warwick have been able to create an accurate 3D model of the brain.

Over a billion individual pieces of data were analysed covering the 47, 636 areas of the brain, called voxels. This data originated from 523 people with autism and 452 people without autism.

The researchers isolated 20 areas of difference where the connections between the voxels in the autistic brain were stronger or weaker than the non‑autistic.

The areas related to face expression processing involved in social behaviour and another in spatial functions, which the researchers propose are linked to the computations involved in theory of mind of oneself or of others and a reduced connectivity in these regions may be contributing to the symptoms of autism.

This methodology may be able to isolate similar areas in people that have other cognitive problems including obsessive compulsive disorder, attention deficit hyperactivity disorder and schizophrenia.


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Podcast: West Herts Drive Time Science Correspondent 03/02/2015

Radio Verulam Science Feature 03/02/2015

Podcast MP3:


Waterproof surfaces

A team from the University of Rochester in New York have reported a method of creating waterproof surfaces that could be used to produce easily maintained and hygienic devices. Material would not suffer from rust or icing up in the cold weather.

The test materials that were used are platinum, titanium and brass. The material “self-cleans” as dust is drawn away with water droplets as they hit the surface.

Previously, waterproofing surfaces has relied on coating with another substance, which fundamentally changing the surface properties of the metal.

The method they have used utilises rapid pulses of high powered lasers etching grooves 0.1 mm apart into the surface. Water droplets bounce off the surface if dropped from a short distance and any water sitting on the surface will slide off if the surface is tilted by approximately 4 degrees. A popular hydrophobic material, Teflon, often used on non-stick frying pans for example, has to be tilted to around 70 degrees before water will slide away.

However, as with many new techniques, it is currently expensive and time consuming to produce these materials. It takes approximately one hour to create one square inch.

There are many other ways to create hydrophobic structures, including coating, chemical etching and electron beams, which are more straightforward.

Source and Video:

Fly by: Pluto

The spacecraft New Horizons is nearing its encounter with Pluto. Launched in 2006, the craft will fly by Pluto in July, but is powering up its systems in preparation, with some images expected back by tomorrow (Tuesday 27th Jan) at the latest. It will be performing correction manoeuvres to make sure the instruments on board will be pointing in the correct direction when it makes its closest approach on 14th July 2015, approximately 11:50 GMT about 13,695 km from the surface. As New Horizons approaches it will be travelling around 14 km s-1, and all the instruments work at different approach distances to get data, so an elaborate observation schedule is planned.

Pluto is one of the “classical” planets, the last to be visited by a space probe. We have been able to remotely observe it using instruments like the Hubble Space Telescope, which has distinguished ‘light’ and ‘dark’ features.

In the same year that New Horizons was launched, the debate about the classification of planetary bodies culminated with the declassification of Pluto as a planet and reclassified as a Dwarf Planet. To be classified as a planet, an object must:

  1. Be in orbit around the Sun.
  2. Be massive enough to be a sphere by its own gravitational force. More specifically, its own gravity should pull it into a shape of hydrostatic equilibrium.
  3. Have cleared the neighbourhood around its orbit.

The Kuiper Belt is thought to contain many thousands of Pluto-like objects, possibly some that are similar in size to Mars and Earth.


Scientist of the Month

Clyde Tombaugh (4th Feb 1906 – 17th Jan 1997, 90)

Built his own telescopes, grinding the lenses and mirrors himself. He drew Jupiter and Mars, which earned him a job at Lowell Observatory.

He was given the task of search for Planet X, a planet hypothesised by Percival Lowell beyond the orbit of Neptune.

During WWII he taught navigation to naval personnel at Northern Arizona University.

He discovered nearly 800 asteroids, mostly as a by-product during his search for Pluto and other celestial objects.

He also was involved in the search for Near-Earth Objects.


Night Sky This Month

Venus, Mars and Jupiter are all prominent in the night sky this month. Jupiter rises in the east and is available for observing throughout the night. Mars and Venus are setting in the west, and on the 20th Feb will have a fabulous conjunction with the crescent Moon at nightfall on the western horizon.

Full Moon 3rd Feb

Jupiter is at opposition (closest approach to Earth) on 6th Feb, offering the perfect opportunity to view and photograph the planet. Binoculars offer the opportunity to see the four largest moons of Jupiter and a small to medium telescope will show the cloud bands and Great Red Spot.


With thanks to Danny Smith and all the Drive Time Team.


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Science Correspondent 28/04/2014

West Herts Drive Time Science Correspondent 28/04/2014


Longest experiment yields ninth result

An experiment that has been running since 1927, recognised by the Guinness World Record as the longest-running laboratory experiment, has recorded its ninth data point. The experiment is a funnel full of a material known as pitch, which is a viscoelastic, semi-solid polymer. In the past, this material has been used to waterproof and seal seams on wooden boats and other wooden containers. As a highly viscous material, it is hard enough to be hit with a hammer causing it to shatter but under pressure it is able to flow like a liquid, even it is very slowly.

Scientists at the University of Queensland in Australia have been watching the experiment for 87 years. It was originally set up to show students that materials that appear solid can flow like liquids. Some pitch was put into a funnel and allowed to drip into a beaker below. In Dec 1938 the 1st drop fell; the 2nd drop was in February 1947; the 3rd was in April 1954; the 4th, in May 1962; the 5th, August 1970; the 6th, April 1979; the 7th, July 1988; and the 8th dropped in November 2000.

The most recent and ninth drop was on 17th April. Physicist John Mainstone dedicated his time to watching the experiment for drops to occur. He managed to miss all three drops that happened during his custodianship. In 1977, he spent the entire weekend watching it, but missed the drop when he went home exhausted. In 1988, he missed the drop when he went to make a cup of tea. In 2000, by when a webcam had been set up to monitor the experiment, he missed it due a 20 minute power cut due to a tropical storm. Sadly, Professor Mainstone died in August last year. This time due to recording footage of the experiment, the drop has been seen to occur for the first time.

Australia is moving north by six centimetres a year due to continental drift, this experiment moves 10 times slower than that. By the seventh drop, it was possible to calculate the viscosity of pitch as 230 billion times that of water. Common day-to-day viscous materials include toothpaste and tomato purée.




Laser eye surgery for the ears

Other species in the animal kingdom such as fish and birds can regenerate the hair cells in their inner ear over time, but mammals do not have this ability. Over time as we age hearing sensitivity can decrease; or other damage can occur to the inner and outer hair cells – loud noises, some antibiotics and diseases. At present we can only artificially mimic what the ear does to improve hearing loss. Hearing aids amplify sounds and cochlea implants transform sound waves into electrical frequencies so subtleties in voices and music can difficult to differentiate between.

A trial is about to go ahead to test whether results seen in mice can be replicated in humans without any long-term side effects. The mice, which had almost all of their ear hair cells destroyed, had a harmless virus injected into their cochlea and two months later they were able to hear significantly more, around 20 decibels. This is about equivalent to the difference in your hearing normally and holding your hands over your ears.

The team at the University of Kansas Medical Center, lead by Hinrich Staecker are hoping that the only side effect will be short-term dizziness and nausea, which are common after ear surgery anyway. This treatment, if successful, won’t be aiding hearing it will be repairing the ear and restoring the natural hearing processes. They will soon be recruiting volunteers for the study between the ages of 18 and 70; looking for people presently with severe hearing loss, as a risk is that residual hearing could be affected.

It is believed that the approach could help 1 to 2 % of people with hearing loss. The viral gene package will also be directly injected into the volunteers’ cochlea, and once the gene reaches the supporting cells, it instructs them to divide and form new hair cells, with results expected between two weeks and two months later. Tests have been performed to check whether the virus spreads to any other tissue, but it appears to be restricted to the site of injection.

As a laser is used in the process to allow access past the ear drum perhaps if this treatment is successful, we will be seeing adverts on TV for laser ear surgery in the future.




Scientist of the Month

Edward Jenner (1794 – 1823)

He contributed to the fields of medicine, surgery and natural history. He is most well known for his contribution to the development of vaccination and is known as the “father of immunology”.

He apprenticed in surgery and anatomy under surgeon John Hunter at St George’s Hospital in London. He eventually moved back to the countryside where he grew up and became a family doctor and surgeon.

In natural history, combining observation, experiment and dissection, he studied the cuckoo and found, contrary to belief that it is the cuckoo hatchlings that push the eggs and hatchling birds out of the nest, not the adult cuckoos. He discovered that the baby cuckoos have a depression in its back for the first 12 days of its life in order to cup the eggs and other chicks native to the nest and uses that to push them out.

He advanced the understanding of the heart condition angina.

Smallpox was a common disease at the time and Jenner noticed that milkmaids seemed to be more generally immune to smallpox and he hypothesed that they were protected from smallpox after having been infected and survived a bout of cowpox. Cowpox is similar, but much milder than the highly contagious and often lethal smallpox.

Jenner purposely infected the son of his gardener with cowpox, giving him symptoms including a fever and uneasiness, but not a full infection. He later injected him with smallpox but no disease followed. He injected the boy a second time, but again with no sign of infection. He had created an immunity to smallpox without people having to be inoculated with smallpox, which was the current method where material taken from someone who had recently had smallpox and hoping the person inoculated with that material only suffered a mild form of smallpox.

Jenner’s method proved much more effective and less dangerous than the previous method and has led to smallpox being declared an eradicated disease in 1979 by the World Health Organisation.

He has a crater named after him on the Moon.




Night Sky This Month

Jupiter is still high in the sky and makes for excellent observing, even though it is passed opposition. The Great Red Spot (a storm that has been raging for at least 300 years) has become more prominent and perhaps can even be viewed in a small telescope.

Mars has reached opposition this month so from now on will be getting smaller in angular size, making viewing surface features harder. With a small telescope and good seeing it should be possible to make out the northern polar cap and Syrtis Major – dark, triangular shaped region.

The crater named after Edward Jenner, the “father of immunology” is on the south eastern edge of the Moon as viewed from Earth in the region known as Mare Australe and can sometimes be seen when the Moon slightly wobbles on its axis in the right direction.

The constellation of Leo prominent in the night sky currently and has several Messier galaxies and at the base of the lion’s neck, a double star or binary system called Algieba which can be viewed with a telescope.