News:
New telescope may unveil alien volcanoes
Friday, 10 September 2010 Stuart Gary
ABC
Artist's conception shows an extremely volcanic moon
New research suggests that astronomers using the James Webb Space Telescope may detect volcanic activity on a distant exoplanets (Source: Wade Henning)
Related Stories
* Exoplanet bonanza fuels excitement, Science Online, 28 Jul 2010
* Super-Earth has rocky surface: study, Science Online, 22 Oct 2009
* Alpha Centauri may have Earth-like worlds, Science Online, 19 Mar 2008
Scientists will soon be able to study volcanoes on worlds beyond our solar system, according to a new study.
Reporting in the Astrophysical Journal, Dr Lisa Kaltenegger an astronomer with the Harvard-Smithsonian Centre for Astrophysics, and colleages, believe the future James Webb Space Telescope (JWST) will allow scientists to detect eruptions on rocky planets orbiting nearby stars.
They say the JWST, due to be launched in 2014, should be able to detect faint signs of volcanism on a rocky planet less than 30 light-years away.
"Using the James Webb Space Telescope, we could spot an eruption 10 to 100 times the size of Pinatubo for the closest stars," says Kaltenegger.
The 1991 eruption of Mount Pinatubo in the Philippines spewed 17 million tonnes of sulphur dioxide into the stratosphere, and was one of the largest volcanic eruptions in recent times.
Volcanic models
In their study Kaltenegger's team developed models to explain how eruptions on exoplanets leave a telltale atmospheric signature.
They found sulphur dioxide from very large, explosive eruptions is potentially measurable because of the volume of material produced and the time it takes to "wash out of the atmosphere".
To look for volcanic sulphur dioxide, astronomers would rely on a technique known as secondary eclipse, which requires the exoplanet to cross behind its parent star as seen from Earth.
By collecting light from the star and planet, then subtracting the starlight (while the planet is hidden), astronomers are left with the signal from the planet alone.
They can search that signal using spectroscopy for signs of particular chemical molecules.
"Our first sniffs of volcanoes from an alien Earth might be pretty rank," says Kalteneger. "Seeing a volcanic eruption on an exoplanet will show us similarities or difference among rocky worlds."
Comparitive lessons
Planetary scientist Dr Simon O'Toole from the Australian Astronomical Observatory says exoplanetary volcanism would give new insights into the physics and geology of planets.
"But the solar system itself is a target-rich environment. Places like Io and Venus shows us volcanism in action on other worlds," says O'Toole.
"And let's not forget cryovolcanism of the type we see on Saturn's moons Titan and Enceladus, or the Neptunian ice moon Triton."
Reflection:
If this is really true, I'm delighted. We all know that on the Venus, there is a lot of volcanos. I'm really looking forward to seeing the video footage of volcano movements on Venus or one of Saturn's moon. I could not believe how fast technology is improving. A few hundred years back, we don't even know there is a solar system, but now, we can see even a small detail on one of Saturn's moon.
However, I think that to be able to see the movements of other planets, the steps taken is over complex and that there is no need to splash all our money on looking at other planets. We are on the Earth and thats it. Anything beyond Earth is basically none of our buisness unless the Mars explodes or something. What is the point of looking at Mars when you know in your life, you are not going to visit it?
However, I must still praise the scientists who found that this can be humanly possible. Since this might be useful to finding out what the solar system was like maybe a few thousand years ago. But really, its mainly money down the drain.
2010年9月11日 星期六
2010年9月9日 星期四
Hybrid cars
There have been a lot of hybrid cars in the world, most recently the Milan Mercury have came out, but how exactly does it work? To start off, I shall show you a graph.
To start off, there is a many type of power sources for hybrid cars:
# On-board or out-board rechargeable energy storage system (RESS)
# Petrol
# Diesel
# Hydrogen
# Compressed air
# Liquid nitrogen
# Human powered e.g. pedaling or rowing
# Wind
# Electricity
# Compressed or liquefied natural gas
# Solar
# Waste heat from internal combustion engine.
# Coal, wood or other solid combustibles
# Electromagnetic fields, Radio waves
The most common type of combinations are actually petrol-electricity, diesel electricity and the most fuel efficient diesel-electric. However, most cars does not use equal amounts of each energy at the same time, as power sources such as solar and wind are not always guranteed and electricity will run out quite fast and putting a lot of battery will affect the aerodynamics of the car quite badly. So, most hybrid cars use 80% fuel(petrol and diesel) and 20% others.
The main reason why hybrid cars are becoming more and more popular is that its fuel consumption is genuinely low. For example, a normal Honda Civic goes 24 miles to a gallon when traveling at 96km/h. However, traveling at the same speed, the hybrid Civic can hit 45mpg! So, by spending $5000 more to buy a hybrid car, you halved the amount you pay for fuel.
Hybrid cars also genuinely pollutes less because the 2 power sources share the job and thus produce less emmusions. This is because if you have a diesel-solar car, in which diesel pollutes very much, the solar cell share the job of running the car. So the diesel engine will be valving less and causing less pollution.
However, I think that hybrid is not the way forward. They are being used in a incorrect way. Because in the UK, cars are taxed by how much they pollute the country. So, a car firm built a petrol-electric car that only have enough electricity to run for a mere 6 miles and then its petrol all the way. This is just a way to sell your car. Mind you, 6 mile is basically 9.6km, which is from Tuas Second Link to just after Boon Lay, which is not even enough to get you to the city if you live in Marine Parade. So, don't buy a scam hybrid car, get yourself a normal road car.
To start off, there is a many type of power sources for hybrid cars:
# On-board or out-board rechargeable energy storage system (RESS)
# Petrol
# Diesel
# Hydrogen
# Compressed air
# Liquid nitrogen
# Human powered e.g. pedaling or rowing
# Wind
# Electricity
# Compressed or liquefied natural gas
# Solar
# Waste heat from internal combustion engine.
# Coal, wood or other solid combustibles
# Electromagnetic fields, Radio waves
The most common type of combinations are actually petrol-electricity, diesel electricity and the most fuel efficient diesel-electric. However, most cars does not use equal amounts of each energy at the same time, as power sources such as solar and wind are not always guranteed and electricity will run out quite fast and putting a lot of battery will affect the aerodynamics of the car quite badly. So, most hybrid cars use 80% fuel(petrol and diesel) and 20% others.
The main reason why hybrid cars are becoming more and more popular is that its fuel consumption is genuinely low. For example, a normal Honda Civic goes 24 miles to a gallon when traveling at 96km/h. However, traveling at the same speed, the hybrid Civic can hit 45mpg! So, by spending $5000 more to buy a hybrid car, you halved the amount you pay for fuel.
Hybrid cars also genuinely pollutes less because the 2 power sources share the job and thus produce less emmusions. This is because if you have a diesel-solar car, in which diesel pollutes very much, the solar cell share the job of running the car. So the diesel engine will be valving less and causing less pollution.
However, I think that hybrid is not the way forward. They are being used in a incorrect way. Because in the UK, cars are taxed by how much they pollute the country. So, a car firm built a petrol-electric car that only have enough electricity to run for a mere 6 miles and then its petrol all the way. This is just a way to sell your car. Mind you, 6 mile is basically 9.6km, which is from Tuas Second Link to just after Boon Lay, which is not even enough to get you to the city if you live in Marine Parade. So, don't buy a scam hybrid car, get yourself a normal road car.
2010年9月5日 星期日
Science reflection on bacteria
Article:
Skin is Home to Zoo of Bacteria
February 2007 - A new study by Martin J. Blaser, Chair of the Department of Medicine and Professor of Microbiology at NYU School of Medicine, and others, published in the online edition of the Proceedings of the National Academy of Sciences has found that human skin, the largest organ in the body, is "home to a virtual zoo of bacteria."
Led by senior research scientist Zhan Gao, MD, the research took more than three years to complete and used a powerful molecular method to sample bacteria on the forearms of six healthy subjects. Analysis identified 182 species of which 8 per cent were previously unknown.
Martin Blaser commented:
"This is essentially the first molecular study of the skin. There are probably fewer than ten labs in the US looking at this question. It is very intensive work."
This research, part of ongoing studies of human microbial ecology, found that some bacteria appeared to be effectively permanent resident on the skin; others were transient. Researchers explain that that the body has ten times more microbes than cells, with bacterial populations changing according to how we live. Maintaining population stability may contribute to health.
Researchers took swabs from three male and three female volunteers' inner right and left forearms halfway between the wrist and the elbow. Four of the individuals were retested 8 to10 months later. About half (54.4 per cent) of bacteria identified were species known to be effectively permanently resident on human skin (Propionibacteria, Corynebacteria, Staphylococcus and Streptococcus). However, the six individuals differed markedly in the overall composition of bacteria sampled with only four species in common (Propionibacterium acnes, Corynebacterium tuberculostearicum, Streptococcus mitis, and Finegoldia AB109769).
Zhan Gao said:
"This is a surprise. But many things affecting the skin affect bacteria, such as the weather, exposure to light, and cosmetics use."
The study found that 71.4 per cent of the species were unique to individual subjects, suggesting that the skin surface is highly diversified in terms of bacteria harbored. Three species were found in male subjects only (Propionibacterium granulosum, Corynebacterium singulare, and Corynebacterium appendixes). While not conclusive, researchers suggest that that there may be gender differences in the pattern of species harbored. Researchers found that bacterial populations varied over time but each individual had a core predominant set.
Martin Blaser explained:
"What that suggests is that there is a scaffold of bacteria present in everybody's skin. Some stay and others come and go."
Researchers point out that skin condition is affected by a variety of factors such as climate, diet, personal hygiene, and disease. Skin is never free of bacteria but these are not pathogenic in healthy people.
Martin Blaser added:
"Many of the bacteria of the human body are still unknown. We all live with bacteria all our lives and occasionally we smile, so they're not that bad for us."
Reflection:
I am very surprised by the fact that 142 types of bacteria live on our skin, and 11 of them are previously unknown. I am also happy to know that the bacterias are not pathogenic to normal healthy people. This meant that I can not worry about this kind of micro organisms on my skin. This discovery might just relieve many people from their worries that the micro organisms might damage their health. Even though most of the bacteria are unique to certain objects, some are not. So our hand might share the same bacteria with our hair! It is very frightening to discover this, as I genuinely thought that our hair is more dirty than our hands, and all the bacteria in it is pretty dangerous.
However, I am also relieved to know that most of the bacterias are unique to each body part as it would be safer to know that even if our kidney share bacteria with our intestines, it's not very much. This will definately relieve me of my worries that my heart will one day become like my intestines.
This discovery is a very significant to me one as it helps us understand what is actually on our body. It also helps us to know that even though a bacteria might be dangerous, it isn't really as dangerous as we thought. There might even be extremely useful bacterias lying on my hand the very moment I am typing the words that is helping me with something. But I don't really think that this will be the grand total number of bacterias on our body, so scientists all over the world, please discover the rest.
Skin is Home to Zoo of Bacteria
February 2007 - A new study by Martin J. Blaser, Chair of the Department of Medicine and Professor of Microbiology at NYU School of Medicine, and others, published in the online edition of the Proceedings of the National Academy of Sciences has found that human skin, the largest organ in the body, is "home to a virtual zoo of bacteria."
Led by senior research scientist Zhan Gao, MD, the research took more than three years to complete and used a powerful molecular method to sample bacteria on the forearms of six healthy subjects. Analysis identified 182 species of which 8 per cent were previously unknown.
Martin Blaser commented:
"This is essentially the first molecular study of the skin. There are probably fewer than ten labs in the US looking at this question. It is very intensive work."
This research, part of ongoing studies of human microbial ecology, found that some bacteria appeared to be effectively permanent resident on the skin; others were transient. Researchers explain that that the body has ten times more microbes than cells, with bacterial populations changing according to how we live. Maintaining population stability may contribute to health.
Researchers took swabs from three male and three female volunteers' inner right and left forearms halfway between the wrist and the elbow. Four of the individuals were retested 8 to10 months later. About half (54.4 per cent) of bacteria identified were species known to be effectively permanently resident on human skin (Propionibacteria, Corynebacteria, Staphylococcus and Streptococcus). However, the six individuals differed markedly in the overall composition of bacteria sampled with only four species in common (Propionibacterium acnes, Corynebacterium tuberculostearicum, Streptococcus mitis, and Finegoldia AB109769).
Zhan Gao said:
"This is a surprise. But many things affecting the skin affect bacteria, such as the weather, exposure to light, and cosmetics use."
The study found that 71.4 per cent of the species were unique to individual subjects, suggesting that the skin surface is highly diversified in terms of bacteria harbored. Three species were found in male subjects only (Propionibacterium granulosum, Corynebacterium singulare, and Corynebacterium appendixes). While not conclusive, researchers suggest that that there may be gender differences in the pattern of species harbored. Researchers found that bacterial populations varied over time but each individual had a core predominant set.
Martin Blaser explained:
"What that suggests is that there is a scaffold of bacteria present in everybody's skin. Some stay and others come and go."
Researchers point out that skin condition is affected by a variety of factors such as climate, diet, personal hygiene, and disease. Skin is never free of bacteria but these are not pathogenic in healthy people.
Martin Blaser added:
"Many of the bacteria of the human body are still unknown. We all live with bacteria all our lives and occasionally we smile, so they're not that bad for us."
Reflection:
I am very surprised by the fact that 142 types of bacteria live on our skin, and 11 of them are previously unknown. I am also happy to know that the bacterias are not pathogenic to normal healthy people. This meant that I can not worry about this kind of micro organisms on my skin. This discovery might just relieve many people from their worries that the micro organisms might damage their health. Even though most of the bacteria are unique to certain objects, some are not. So our hand might share the same bacteria with our hair! It is very frightening to discover this, as I genuinely thought that our hair is more dirty than our hands, and all the bacteria in it is pretty dangerous.
However, I am also relieved to know that most of the bacterias are unique to each body part as it would be safer to know that even if our kidney share bacteria with our intestines, it's not very much. This will definately relieve me of my worries that my heart will one day become like my intestines.
This discovery is a very significant to me one as it helps us understand what is actually on our body. It also helps us to know that even though a bacteria might be dangerous, it isn't really as dangerous as we thought. There might even be extremely useful bacterias lying on my hand the very moment I am typing the words that is helping me with something. But I don't really think that this will be the grand total number of bacterias on our body, so scientists all over the world, please discover the rest.
2010年9月3日 星期五
F1 weight
There is quite a lot of things that affects the weight of an F1 car, including gear ratio, weight distribution, amount of fuel and length of wings. According to former F1 driver Martin Brundle, his Zakspeed F1 car in 1987 is so heavy that it made him lose 2s to the leading driver at that time. It is widely thought that the weight of a F1 car can amount to up to 6 seconds on an average track. This is because for every kg more in the car, it greatly increases grip and thus making handling and getting up to speed in the straights more difficult. The sheer amount of effort needed to execute a chicane gradually increases. The mass of the the driver also affects the speed of the car, especially on highspeed circuits like Monza and AVUS. This is because any extra kg in the cockpit means that there is more downforce, which is a nuisance in the high speed straights. The engine used is also very important, as the Ferrari V16 used in 1994 was so much more heavier than the Renault V8 even though that they have genuinely the same amount of power, the heavy engine disrupt the weight balance so much that Jean Alesi's 13 seconds lead to Michael Schumacher was cut to nought in 5 laps!
2010年8月29日 星期日
2010年8月20日 星期五
2010年8月14日 星期六
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