Today, is the 15th day of August in the Chinese calendar, and is also Mid-Autumn Festival. I believe that the Mid-Autumn Festival is not all about the celebrations, but there are things about it, that has much Science involved.
To start of, I would be discussing on the patterns of the Moon. One common idea about the Mid-Autumn Festival, is that people come together to appreciate the Full Moon. Generally, the Moon follows around a 28 day cycle. The cycle is like this.
CYCLE
New Moon -> Waxing Crescent -> First Quarter -> Waxing Gibbous -> Full Moon -> Waning Gibbous -> Third Quarter -> Waning Crescent -> New Moon
The New Moon is on the 0th and 28th day of the cycle and the Full Moon is around the 14th to 16th day of the cycle. Since the Chinese calendar is a lunar one, on the 15th of every Chinese month, the Moon will be at its Full Moon stage. I find this a very interesting occasion. Every month, the Moon revolves around the Earth at the exact same route, to enable this phenomenon to be possible. This is a simple beauty of nature, and we should learn to appreciate it.
Mid-Autumn Festival does not just mark a date for the Chinese to celebrate, but also a period for the Chinese to prepare for the next season, the Winter. The four seasons is another amazing phenomenon that happens because of Nature. The four seasons is possible because of the Earth's axial tilt at 23.4°. During the period from May to July, the Northern Hemisphere would be the side facing more of the Sun, thus having longer hours of sunlight, and thus undergo Summer. While on the other hand, the Southern Hemisphere would be the side facing less of the Sun, thus having shorter hours of sunlight, and thus undergoes Winter. These phenomenons would swoop during the period from November to January, with the Northern Hemisphere having Winter and the Southern Hemisphere having Summer.
I find this another very interesting beauty of nature. These four seasons come and go automatically, and is all controlled by nature. In my opinion, nature is a beauty in itself. The Earth is tilted at 23.4°, the Moon revolves around the Earth in exactly 28 days; all these were not controlled by Man, and yet produce such amazing outcomes.
In conclusion, I believe that nature's beauty cannot be seen on the outside. It is up to us to explore nature and discover the beauty in it, and feel it deep with our hearts.
Monday, September 12, 2011
Wednesday, September 7, 2011
Reflection of Term 3 results
Today, I would be reflecting on my Term 3 results and compare it to my results in Term 1 and 2.
GRADES
Term 1 - 70 (A2)
Term 2 - 65 (B3)
Term 3 - 76.25 (A1)
Overall, my Term 3 grades have improved from Term 1 and Term 2's. I believe this is not just about luck, but is about the efforts I have put in to study for the test. For example, I still can recount not understanding anything about lenses when it was thought in Term 2. I did not understand how light rays refract and was clueless on how to draw light rays that pass through lens. Seeing this could lead to a disastrous Term 3 result, I put in extra efforts during the June Holidays to study about lenses. I referred to every source possible, the textbook, the Internet, and worksheets etc. Finally, the test came, and I was prepared for it. I managed to solve most questions, but there were a few that I had difficulties with. Nevertheless, I did my best and managed to get an A1. I am pleased with my result as it was my best this year, and is also a reminder to me that hard work is the key to success.
As the EOYs approach, I would definitely work hard, and achieve this same feat again.
GRADES
Term 1 - 70 (A2)
Term 2 - 65 (B3)
Term 3 - 76.25 (A1)
Overall, my Term 3 grades have improved from Term 1 and Term 2's. I believe this is not just about luck, but is about the efforts I have put in to study for the test. For example, I still can recount not understanding anything about lenses when it was thought in Term 2. I did not understand how light rays refract and was clueless on how to draw light rays that pass through lens. Seeing this could lead to a disastrous Term 3 result, I put in extra efforts during the June Holidays to study about lenses. I referred to every source possible, the textbook, the Internet, and worksheets etc. Finally, the test came, and I was prepared for it. I managed to solve most questions, but there were a few that I had difficulties with. Nevertheless, I did my best and managed to get an A1. I am pleased with my result as it was my best this year, and is also a reminder to me that hard work is the key to success.
As the EOYs approach, I would definitely work hard, and achieve this same feat again.
NASA find evidence of water on Mars
The planet Mars has offered new evidence that water trickles down the slopes of its craters, say scientists examining pictures from a NASA probe in Martian orbit.
Mars water? Scientists say the pictures don't prove it, but they fit with other evidence from other probes.
The spacecraft, Mars Reconnaissance Orbiter, has been circling Mars since 2006, and during that time, Mars -- which has seasons like ours -- has gone around the sun three times. Each year, MRO photographed brown streaks in the Martian spring and summer. In the colder seasons, they disappeared.
"The best explanation for these observations so far is the flow of briny water," said Alfred McEwen of the University of Arizona, the principal investigator using the ship's high-resolution camera system.
Mars, located at least 35 million miles farther from the sun than us, is far colder than Earth. But if water is thick with salt and other minerals, its freezing point would be lower than it is for clear water here.
"We expect water on Mars to be briny, to be salty, because we know that the surface is salty from all of the past landers and rovers," said McEwen. "Furthermore, the salt serves to depress the freezing point of the water, so in places where it's below freezing, we see this activity, it is still plausible for that to be salty water."
McEwen and his team published their findings in Friday's issue of the journal Science. They reported that the streaks appeared only on steep slopes. They could be hundreds of yards long, and often resembled gullies on Earth.
Other readings showed no chemical signal on the Martian surface, leading the scientists to suggest it may dry very quickly, or be just below the upper layer of Martian dust.
"These dark lineations are different from other types of features on Martian slopes," said Richard Zurek, the project scientist for MRO, in a statement. "Repeated observations show they extend ever farther downhill with time during the warm season."
'Follow the Water'
This is not the first suggestion of Martian water. For the last 15 years, NASA has been looking for it, because water would be a very good sign for past -- or even present -- microbial life there.
In 2004, the Mars rover Opportunity found chemical compounds that scientists said most likely would have formed if there had once been standing water on the Martian surface. Steven Squyres, the rovers' chief scientist, said at the time he could imagine Mars, eons ago, with pools of ruby-red brackish water where today there is only dust.
In 2006 scientists said images from an orbiter, Mars Global Surveyor, showed streaks that seemed to come and go from the walls of craters; the theory at the time was that underground water may be spurting through the surface. Doubters said the "gullies" did not resemble ones formed by liquid in Earth.
In 2008, another probe, called Phoenix, landed near Mars' north pole, and produced some pictures showing strange blobs on the struts of its landing legs. Briny ice? Scientists argued for months.
But NASA has made no secret of its hope to find water on Mars.
"NASA's Mars Exploration Program keeps bringing us closer to determining whether the Red Planet could harbor life in some form," NASA Administrator Charles Bolden said today, "and it reaffirms Mars as an important future destination for human exploration."
~ ABC News
This news is certainly a very intriguing find for NASA. Previously, Mars have frequently said to have life on it, but there were insufficient evidence to prove it. Now, this discovery can almost certainly show that life exists or existed on Mars.
In the past decades, scientists have repeatedly stated that life on Mars is possible, because of similar climate to Earth. Mars is merely 35 million miles away from us, and about 20% further away from the Sun than us. This allows Mars to have similar temperatures as us, not too hot like Mercury and Venus, and also, not too cold like Uranus and Neptune.
I personally find this discovery very exciting. For me, having been interested in Space since young, I had been frequently updating myself on any discoveries made by scientists. This discovery of possible water on Mars, is definitely one that am intrigued by. If further studies can really prove that water is present on Mars, it would be an entire new era of Space studies. I hope scientists would continue pursuing studies in this field, and one day, make a mind-blowing discovery.
Mars water? Scientists say the pictures don't prove it, but they fit with other evidence from other probes.
The spacecraft, Mars Reconnaissance Orbiter, has been circling Mars since 2006, and during that time, Mars -- which has seasons like ours -- has gone around the sun three times. Each year, MRO photographed brown streaks in the Martian spring and summer. In the colder seasons, they disappeared.
"The best explanation for these observations so far is the flow of briny water," said Alfred McEwen of the University of Arizona, the principal investigator using the ship's high-resolution camera system.
Mars, located at least 35 million miles farther from the sun than us, is far colder than Earth. But if water is thick with salt and other minerals, its freezing point would be lower than it is for clear water here.
"We expect water on Mars to be briny, to be salty, because we know that the surface is salty from all of the past landers and rovers," said McEwen. "Furthermore, the salt serves to depress the freezing point of the water, so in places where it's below freezing, we see this activity, it is still plausible for that to be salty water."
McEwen and his team published their findings in Friday's issue of the journal Science. They reported that the streaks appeared only on steep slopes. They could be hundreds of yards long, and often resembled gullies on Earth.
Other readings showed no chemical signal on the Martian surface, leading the scientists to suggest it may dry very quickly, or be just below the upper layer of Martian dust.
"These dark lineations are different from other types of features on Martian slopes," said Richard Zurek, the project scientist for MRO, in a statement. "Repeated observations show they extend ever farther downhill with time during the warm season."
'Follow the Water'
This is not the first suggestion of Martian water. For the last 15 years, NASA has been looking for it, because water would be a very good sign for past -- or even present -- microbial life there.
In 2004, the Mars rover Opportunity found chemical compounds that scientists said most likely would have formed if there had once been standing water on the Martian surface. Steven Squyres, the rovers' chief scientist, said at the time he could imagine Mars, eons ago, with pools of ruby-red brackish water where today there is only dust.
In 2006 scientists said images from an orbiter, Mars Global Surveyor, showed streaks that seemed to come and go from the walls of craters; the theory at the time was that underground water may be spurting through the surface. Doubters said the "gullies" did not resemble ones formed by liquid in Earth.
In 2008, another probe, called Phoenix, landed near Mars' north pole, and produced some pictures showing strange blobs on the struts of its landing legs. Briny ice? Scientists argued for months.
But NASA has made no secret of its hope to find water on Mars.
"NASA's Mars Exploration Program keeps bringing us closer to determining whether the Red Planet could harbor life in some form," NASA Administrator Charles Bolden said today, "and it reaffirms Mars as an important future destination for human exploration."
~ ABC News
This news is certainly a very intriguing find for NASA. Previously, Mars have frequently said to have life on it, but there were insufficient evidence to prove it. Now, this discovery can almost certainly show that life exists or existed on Mars.
In the past decades, scientists have repeatedly stated that life on Mars is possible, because of similar climate to Earth. Mars is merely 35 million miles away from us, and about 20% further away from the Sun than us. This allows Mars to have similar temperatures as us, not too hot like Mercury and Venus, and also, not too cold like Uranus and Neptune.
I personally find this discovery very exciting. For me, having been interested in Space since young, I had been frequently updating myself on any discoveries made by scientists. This discovery of possible water on Mars, is definitely one that am intrigued by. If further studies can really prove that water is present on Mars, it would be an entire new era of Space studies. I hope scientists would continue pursuing studies in this field, and one day, make a mind-blowing discovery.
Thursday, March 10, 2011
Missing bits of DNA may define humans
In evolution as on reality TV, sometimes the biggest loser is really a winner.
Losing 510 chunks of DNA may have enabled humans to develop bigger brains, spineless penises and other human traits, researchers from Stanford University and their colleagues report in the March 10 Nature.
The research is the latest attempt to find genetic factors that make humans human. Previously researchers have searched for genes that humans have but other species do not, but the new study turns that approach on its head, looking instead for pages redacted from the human genetic instruction book during the course of evolution.
“This is a clever thing to do and as so often with good ideas, seems almost obvious in hindsight,” says Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Looking for missing DNA that could shape human traits was something of a no-brainer for Stanford researchers David Kingsley and Gill Bejerano. Kingsley, a developmental geneticist, had previously discovered that stickleback fish species can shed prominent pelvic spines by losing a bit of DNA involved in growing limbs and other appendages (SN: 1/31/09, p. 26).
The team looked at the genetic blueprints of humans, chimpanzees and macaques to see if humans were missing any pieces found in the other two species.
Indeed, humans lack many chunks of DNA that chimps, macaques and mice all seem to share — at least 510 different bits. Most are also missing from Neandertals, suggesting that the pieces were lost sometime between 500,000 and 6 million years ago.
Only one of the missing bits contained an actual gene. The rest of the absent genetic instructions may be important switches for turning on genes. Such switches, known as enhancers, can be located far from a gene but still govern when and where the gene is flipped on during development.
Humans and chimps have roughly the same set of genes, and yet have clear physical and behavioral differences. Some scientists have reasoned that changing the way genes are used — by turning a gene on or off in a particular tissue or during a phase of development — may be a way to evolve new characteristics without damaging important genes. Adding or deleting enhancers is one way to regulate gene activity.
“It’s probably the best way to develop new functionality in the short run,” says David Haussler, a Howard Hughes Medical Institute investigator at the University of California, Santa Cruz.
Because most of the missing chunks of DNA don’t contain genes, it is difficult to say exactly what the pieces are supposed to do. The Stanford team used “a very clever computational analysis” to tease out a couple of pieces of DNA that might have clear-cut functions, Haussler says.
One of the bits is near a gene that controls production of an androgen receptor, a protein that detects testosterone. The piece of DNA missing in humans is an enhancer for the gene, which controls the production of facial sensory whiskers and small spines on the penises of both chimps and mice, the researchers found. Since humans don’t have the enhancer, the gene is not turned on, and sensory whiskers and penile spines fail to develop.
In some mammals, penile spines are prominent and may help males achieve ejaculation quickly. “The key to reproductive success is impregnation, and the faster you can achieve that, the better,” says Owen Lovejoy, a biological anthropologist at Kent State University in Ohio. But even though the loss of the spines makes copulation last longer, it hasn’t hurt the reproductive success of humans, he says. Longer copulation times may help cement bonds between mating partners, which Lovejoy says has been a key to humans’ evolutionary success.
Another missing enhancer identified in the new study may help explain the evolution of human brain size. The enhancer lies next to a tumor-suppressing gene called GADD45G, which normally reins in cell growth so that cancer doesn’t develop. In mice and chimps, the enhancer DNA turns the gene on in the brain. Because humans lack the enhancer, the gene is not turned on in the brain and brain cells may proliferate, possibly contributing to bigger brains.
The enhancer probably isn’t the only thing that led to humans’ increased brain power, Kingsley says. “There’s no way changes in a single gene are going to produce all the interesting changes that led to the human brain.”
Removing the enhancer from mice may help researchers learn just how much brain growth the missing piece of DNA is responsible for, he says.
(www.sciencenews.org)
I feel that this a very amazing and intriguing fact that scientists have discovered. This shows that over the years, the human kind have evolved a lot, and changed totally in terms of size and behaviour. This could be due to the change in environment, thus causing man to evolve to adapt to his surroundings. This emphasises on the importance of genes. Genes are the things that differentiate us from whether we are a man, chimpanzees or macaques. I believe that if Science continues to be this advanced, scientists may even be able to customize genes, combine genese of two organsims. For example, scientists may be able to joint together Man and fish genes, producing an organism that can think as well as humans and also able to swim very well.
Losing 510 chunks of DNA may have enabled humans to develop bigger brains, spineless penises and other human traits, researchers from Stanford University and their colleagues report in the March 10 Nature.
The research is the latest attempt to find genetic factors that make humans human. Previously researchers have searched for genes that humans have but other species do not, but the new study turns that approach on its head, looking instead for pages redacted from the human genetic instruction book during the course of evolution.
“This is a clever thing to do and as so often with good ideas, seems almost obvious in hindsight,” says Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Looking for missing DNA that could shape human traits was something of a no-brainer for Stanford researchers David Kingsley and Gill Bejerano. Kingsley, a developmental geneticist, had previously discovered that stickleback fish species can shed prominent pelvic spines by losing a bit of DNA involved in growing limbs and other appendages (SN: 1/31/09, p. 26).
The team looked at the genetic blueprints of humans, chimpanzees and macaques to see if humans were missing any pieces found in the other two species.
Indeed, humans lack many chunks of DNA that chimps, macaques and mice all seem to share — at least 510 different bits. Most are also missing from Neandertals, suggesting that the pieces were lost sometime between 500,000 and 6 million years ago.
Only one of the missing bits contained an actual gene. The rest of the absent genetic instructions may be important switches for turning on genes. Such switches, known as enhancers, can be located far from a gene but still govern when and where the gene is flipped on during development.
Humans and chimps have roughly the same set of genes, and yet have clear physical and behavioral differences. Some scientists have reasoned that changing the way genes are used — by turning a gene on or off in a particular tissue or during a phase of development — may be a way to evolve new characteristics without damaging important genes. Adding or deleting enhancers is one way to regulate gene activity.
“It’s probably the best way to develop new functionality in the short run,” says David Haussler, a Howard Hughes Medical Institute investigator at the University of California, Santa Cruz.
Because most of the missing chunks of DNA don’t contain genes, it is difficult to say exactly what the pieces are supposed to do. The Stanford team used “a very clever computational analysis” to tease out a couple of pieces of DNA that might have clear-cut functions, Haussler says.
One of the bits is near a gene that controls production of an androgen receptor, a protein that detects testosterone. The piece of DNA missing in humans is an enhancer for the gene, which controls the production of facial sensory whiskers and small spines on the penises of both chimps and mice, the researchers found. Since humans don’t have the enhancer, the gene is not turned on, and sensory whiskers and penile spines fail to develop.
In some mammals, penile spines are prominent and may help males achieve ejaculation quickly. “The key to reproductive success is impregnation, and the faster you can achieve that, the better,” says Owen Lovejoy, a biological anthropologist at Kent State University in Ohio. But even though the loss of the spines makes copulation last longer, it hasn’t hurt the reproductive success of humans, he says. Longer copulation times may help cement bonds between mating partners, which Lovejoy says has been a key to humans’ evolutionary success.
Another missing enhancer identified in the new study may help explain the evolution of human brain size. The enhancer lies next to a tumor-suppressing gene called GADD45G, which normally reins in cell growth so that cancer doesn’t develop. In mice and chimps, the enhancer DNA turns the gene on in the brain. Because humans lack the enhancer, the gene is not turned on in the brain and brain cells may proliferate, possibly contributing to bigger brains.
The enhancer probably isn’t the only thing that led to humans’ increased brain power, Kingsley says. “There’s no way changes in a single gene are going to produce all the interesting changes that led to the human brain.”
Removing the enhancer from mice may help researchers learn just how much brain growth the missing piece of DNA is responsible for, he says.
(www.sciencenews.org)
I feel that this a very amazing and intriguing fact that scientists have discovered. This shows that over the years, the human kind have evolved a lot, and changed totally in terms of size and behaviour. This could be due to the change in environment, thus causing man to evolve to adapt to his surroundings. This emphasises on the importance of genes. Genes are the things that differentiate us from whether we are a man, chimpanzees or macaques. I believe that if Science continues to be this advanced, scientists may even be able to customize genes, combine genese of two organsims. For example, scientists may be able to joint together Man and fish genes, producing an organism that can think as well as humans and also able to swim very well.
Tuesday, March 8, 2011
Space Shuttle Discovery Makes Final Return to Earth Wednesday
CAPE CANAVERAL, Fla. -- Space shuttle Discovery is scheduled to return to Earth for the final time on Wednesday, March 9, completing a 13-day mission to outfit the International Space Station. If Discovery lands Wednesday, it will have spent a total of 365 days in space and traveled more than 148 million miles during 39 flights. It launched on its first mission on Aug. 30, 1984.
This would be Discovery's final journey back to Earth and it is both a happy event but also a sad event. On the good side, Discovery, would be taking a rest, being stored in a museum and boasting a huge number of 39 flights and 148 million miles covered. This is a big feat which no other rockets have done before. However, this also means that Discovery's 27 year long service for astronauts has come to an end. I think this is a huge milestone in man's exploration of the universe.I believe that with the advanced technology today, there might come a day when Man can travel to Mars.
This would be Discovery's final journey back to Earth and it is both a happy event but also a sad event. On the good side, Discovery, would be taking a rest, being stored in a museum and boasting a huge number of 39 flights and 148 million miles covered. This is a big feat which no other rockets have done before. However, this also means that Discovery's 27 year long service for astronauts has come to an end. I think this is a huge milestone in man's exploration of the universe.I believe that with the advanced technology today, there might come a day when Man can travel to Mars.
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