2 1 century scientific and technological achievements

2/KLOC-0 Ten Scientific and Technological Achievements that Illuminate the World in the Decade of the 20th Century

1, water has been found on both Mars and the moon.

On October 4th, 65438/kloc-0 and October 25th, 2004/kloc-0, the American rovers Courage and Opportunity landed on Mars respectively. The greatest achievement of the two rovers was the discovery of evidence of water on Mars. At the same time, the European "Mars Express" probe orbiting around Mars also found frozen water at the South Pole of Mars. This is the first time that humans have found water directly on the surface of Mars. After more than nine months of space travel, the American Phoenix Mars probe successfully landed near the North Pole of Mars on May 25, 2008, which is the first human probe to land near the North Pole of Mars. According to the plan, Phoenix will launch a three-month Mars ground exploration after landing. On July 30th of the same year, the robotic arm of Phoenix sent a soil sample to the heat and gas analyzer. When the sample is heated, the analyzer recognizes that water vapor is generated in it. This is the most direct evidence of the existence of water on Mars.

On June 5438+065438+ 10, 2009, scientists confirmed that there was water on the moon, and the amount was considerable. 10 On June 9th, NASA used a rocket to knock out a hole with a diameter of 100 feet on the surface of the moon, and 25 gallons of water in the form of water vapor and ice were detected in the resulting debris.

2. Complete the sequence map of human genome.

On June 26th, 2000, US President Bill Clinton and British Prime Minister Tony Blair jointly announced that the first draft of the human genome had been completed.

2001February 12, scientists from China, the United States, Japan, Germany, France and Britain jointly published the human genome map and preliminary analysis results.

The most essential content of the human genome project is the DNA sequence diagram of the human genome. The beginning of the human genome project, the focus of debate, the main differences and the main battlefield of competition are all around the sequence diagram. Before the sequence diagram is completed, other diagrams are the foreshadowing of the sequence diagram. In other words, only the birth of sequence diagram marks the completion of the whole human genome project.

On April 15, 2003, on the eve of the 50th anniversary of the publication of the DNA double helix model, the heads of state or government of China, the United States, Japan, Britain, France and Germany signed a document, and the scientists of the six countries jointly announced the completion of the human genome sequence map. The mapping of human genome is an important milestone in the history of human exploration of its own mysteries, which is regarded by many analysts as the symbol of the birth of biotechnology century. In other words, 2 1 century is the century in which biotechnology dominates the world, just as the birth of quantum theory a century ago is considered to have opened the 20th century dominated by physics.

The human genome contains most of the genetic information of human birth, aging, disease and death. Deciphering it will bring a revolution to the diagnosis of diseases, the development of new drugs and the exploration of new treatments.

In 2007, scientists first explained the differences in DNA between people. This is a huge conceptual leap, which will affect everything from how doctors treat diseases to how humans view themselves and protect their privacy.

3. Cell reprogramming technology

Among the top ten scientific advances in 2008 selected by American Science magazine, the progress of reprogramming "customized" cell lines ranked first.

According to Science magazine, these cell lines and related methods of "customizing" them provide researchers with tools to understand and even cure some medical diseases in the future, such as Parkinson's disease and type I diabetes.

The so-called cell reprogramming is to change the development "memory" of cells by implanting new genes, so that they can return to the most primitive embryonic development state and differentiate like embryonic stem cells. Such cells are called "induced pluripotent stem cells". In 2008, two research teams extracted cells from patients with different diseases and reprogrammed them to "transform" them into stem cells. Most of the diseases they choose are difficult or impossible to study with animal models, which makes it more urgent to obtain human cell lines for research.

Science magazine believes that these new cell lines will become an important tool for researchers to understand how diseases occur and develop, and may also help to screen potential drugs in the medical field. If scientists fully master the cell reprogramming technology in the future, and can control this technology more accurately to make it more effective and safe, then patients with different diseases will probably use their own healthy cells to treat diseases.

4. The earliest ancestors of human beings determined

Aldis, which is 4 feet tall (about 65,438+0.265,438+0 meters), has become the oldest hominid ever discovered. She lived 4.4 million years ago until 1992 was discovered. After 17 years of exploration and research, scientists pieced together more than 100 cultural relics unearthed in Ethiopia and successfully restored her skeleton model.

In June 2009, scientists announced this achievement. Surprisingly, as the same ancestor of human beings and chimpanzees, "Aldis" is very different from chimpanzees. In addition, although he lives in the forest, the fact that he can walk upright overturns the previous theory that the open grassland terrain is very important for the development of human biped.

5. Confirm the existence of dark matter in the universe.

In 2003, a multinational team of scientists led by Dr. scranton of the University of Pittsburgh, USA, compared and analyzed the observation data of the American Wilkinson Microwave Anisotropy Exploration Satellite with the results of another observation plan called Sloan Digital Sky Survey. Observation and analysis show that only 4% of the universe is ordinary matter, 23% is dark matter and 73% is dark energy. In 2006, a group of American astronomers observed the collision of distant galaxies through NASA's Chandra X-ray space telescope and other equipment, and found the most direct evidence of the existence of dark matter in the universe. In 2007, European and American scientists published the first three-dimensional map of dark matter in the universe in Nature.

6. The research results of stem cells are rich.

In 2000, cloning and stem cell research made progress. In cloning, scientists have successfully cloned one of the most difficult animals: pigs.

In 2002, Israeli scientists transplanted human "kidney precursor cells" into mice, and they developed into similar organs with some functions, which were about the size of mice's own kidneys.

In 2003, American scientists completed the genetic engineering operation of human embryonic stem cells for the first time, which made the application of stem cells in medical research take a big step forward. Japanese scientists cultivated human embryonic stem cells for the first time; Scientists in China fused human skin cells with rabbit eggs for the first time to cultivate human embryonic stem cells.

In 2006, Australian scientists successfully used a single stem cell to grow new mammary glands in experimental mice for the first time in the world. British scientists used umbilical cord blood stem cells to cultivate miniature artificial liver for the first time.

In 2007, two independent research groups in the United States and Japan announced that they had successfully transformed human skin cells into stem cells almost comparable to embryonic stem cells. This achievement is expected to avoid the ethical controversy that embryonic stem cell research has been facing, thus greatly promoting the research on the treatment of stem cell-related diseases.

7. Important application of nanotechnology

200 1, many important achievements have been made in the field of nanotechnology. After many nanoscale devices were developed in 2000, scientists further connected these nanoscale devices to working circuits, including nanowires, logic circuits based on carbon nanotubes and nanowires, and computable circuits using only one molecular transistor. The leap of molecular computing technology may pave the way for the birth of tiny but extremely fast molecular computers in the future.

In 2003, scientists at the University of California, Berkeley, developed the world's smallest nanomotor with carbon nanotubes.

In 2006, Wang Zhonglin, a professor at Georgia Institute of Technology in the United States, successfully converted mechanical energy into electrical energy on the nanometer scale, and developed the world's smallest generator-nano-generator.

8. The European Hadron Collider started.

The European Large Hadron Collider is the largest hadron collider in the world at present. On September 1 day, 2008, the collider was officially launched. On September 19, the collider was forced to stop running due to an accident.

On1October 20th, 2009, 165438+ the collider was restarted, and the proton flow penetrated the collider for the first time. 2009165438+1October 30th set a new world record for proton acceleration. The collider accelerates two proton streams to the energy level of 1. 1.8 trillion electron volts, breaking the record of 0.98 trillion electron volts set by the accelerator of Fermi National Laboratory in the United States in 2006, 5438+0, making the LHC truly the "strongest machine" in the world. On the evening of February 8, 65438, another proton collision with a total energy of 2.36 trillion electron volts was successfully realized, setting a new record for the highest energy level.

The European Large Hadron Collider was designed in the early 1990s, and about 7,000 scientists and engineers from more than 80 countries and regions, including China, participated in the construction. It is located in a circular tunnel with a total length of about 27 kilometers 100 meters underground in the border area between Switzerland and France near Geneva.

9. The human probe has set the longest record.

In the early morning of June 5438+1October 65438+May, 2005, officials of the European Space Agency announced that the ground control center had received the signal from the probe Huygens through the Cassini spacecraft, indicating that Huygens had successfully landed on Titan. This has set a new record for the longest distance for human probes to land on other celestial bodies.

Huygens probe was launched by Cassini spacecraft in June 1997+00. After seven years' flight of about 3.5 billion kilometers, it entered Saturn's orbit and separated on February 25, 2004.

10, Poincare conjecture proved.

On June 3, 2006, with the joint efforts of mathematicians from the United States, the Russian Federation and China for more than 30 years, two mathematicians from China-Professor Zhu Xiping from Sun Yat-sen University, Professor Cao Huaidong from Caspian University in the United States and part-time professor from Tsinghua University-finally proved the century-old mathematical problem-Poincare conjecture.

1904, French scholar Henri poincare put forward a conjecture: in a closed three-dimensional space, if every closed curve can be shrunk to a point, then this space must be a sphere. Poincare short line has become a mathematical problem that has not been proved for more than 0/00 years.

Poincare conjecture, like Riemann hypothesis and Hodge conjecture, is listed as one of the seven major mathematical century problems.