A chamber lift in the National Ignition Facility.
Credit: Damien Jemison, Lawrence Livermore National Laboratory

Limitless, pollution-free energy is one step closer to becoming a reality. On Dec. 5, 2022, the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in Livermore, California, conducted a controlled nuclear fusion reaction that produced more energy than it consumed.

Nuclear fusion is the combining of two atomic nuclei to form the nucleus of a heavier element. Fusion reactions between low-mass (light) nuclei release a great amount of energy. Fusion produces the energy of the sun and other stars and the explosive force of thermonuclear weapons.

Nuclear fusion releases large amounts of radiation. Fusion occurs when the nuclei of two lightweight elements join to form the nucleus of a heavier one. In the example shown here, nuclei of deuterium and tritium unite and form a helium nucleus.
Credit: World Book illustration by Mark Swindle

The NIF uses a technique called inertial confinement fusion (ICF). In ICF, several extremely powerful lasers hit a fuel pellet about the size of a pencil eraser. The lasers heat the pellet to millions of degrees, causing the nuclei within it to undergo fusion and release energy. In this experiment, the lasers heated the pellet with 2.05 megajoules of energy and the pellet released 3.5 megajoules. NIF scientists and engineers improved the design of the fuel pellet and increased the power of the lasers to make this breakthrough.

If the NIF experiment produced energy, why can’t the facility simply be rebuilt all over the world to provide unlimited power? Although the reaction produced more energy than the energy in the laser light, the lasers themselves are too inefficient for a power plant. The lasers used hundreds of megajoules to produce those 2.05 megajoules of energy in the form of laser light. Furthermore, NIF can only perform up to 3 shots per day in its current configuration. Scientists and engineers estimate that a similar ICF facility will need to perform 10 shots per second to become profitable.

Where, then, does this leave fusion development? NIF scientists and engineers will work to improve their energy gains through fine-tuning their fuel pellets and laser output. But the facility was never meant to be a power plant. NIF was designed for research, particularly into the effects of nuclear weapons. The Comprehensive Nuclear-Test-Ban Treaty prohibits the testing of nuclear weapons, but with NIF, scientists can mimic the conditions of a nuclear blast to develop more efficient nuclear weapons.

Many environmentalists have an uneasy relationship with fusion, in part due to its connection with nuclear weapons research. Some also think that functional fusion power plants will come too late to help slow the progression of global warming. Even with this breakthrough, experts predict that commercial fusion plants are likely at least 40 years away. People also worry that fusion research is taking resources away from research into grid energy storage and is detracting from such financially viable alternatives as wind and solar power.

But the prospective benefits of fusion are too great to ignore. Limitless, pollution-free energy is closer than it ever has been—even though it’s still pretty far away. What will people do with all that power?

Cuban cosmonaut Arnaldo Tamayo Méndez
Credit: Intercosmos

People in the United States observe National Hispanic Heritage Month each year from September 15 to October 15. During this period, Latin American countries celebrate their independence. These countries include Cuba, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, and Nicaragua.

Arnaldo Tamayo Méndez is a Cuban cosmonaut and politician. In Russia and the other former republics of the Soviet Union, astronauts are called cosmonauts. In 1980, Tamayo became the first Black person in space, when he spent a week docked at the Soviet Salyut 6 space station. That same year, he became a member of Cuba’s National Assembly.

Tamayo was born on Jan. 29, 1942, in Guantánamo. After being orphaned as a baby, he was raised by his maternal aunt and uncle. As a child, Tamayo worked many odd jobs, for example shining shoes, selling vegetables, and working as an apprentice carpenter.

After the Cuban dictator Fulgencio Batista fled the country in 1959, Tamayo joined the country’s Revolutionary Army (see Cuba (The Castro revolution). In 1961, he completed studies at the Technical Institute to be an aviation technician. He was then selected to continue studying in the Soviet Union. Tamayo learned how to pilot fighter jets at the Yeisk Higher Military Aviation School in Russia, on the Sea of Azov. He returned to Cuba in 1962 to become a flight instructor for the Cuban Revolutionary Guard. During the Cuban Missile Crisis of 1962, he participated in reconnaissance missions. He also served in the Vietnam War (1957-1975). By 1976, Tamayo had reached the rank of lieutenant colonel in the Cuban air force.

The Soviet Union selected Tamayo to participate in its Intercosmos program in 1978. The program was established to send non-Soviets into space on Soviet spacecraft. Tamayo spent two and a half years training at the Yuri Gargarin Soviet Space Center. On Sept. 18, 1980, Tamayo and the Soviet cosmonaut Yuri Romanenko blasted off on the Soyuz 38 mission. Tamayo became the first person from the Caribbean, the first Cuban, the first Latin American, and the first Black person in space. On the space station Salyut 6, the crew of Soyuz 38 joined other cosmonauts and carried out various experiments designed by Cuban scientists. The mission lasted a little over a week.

Tamayo and Romanenko were both awarded honors after landing. Tamayo became the first person ever awarded the Hero of the Republic of Cuba medal. Additionally, he received medals for Hero of the Soviet Union and the Order of Lenin. Tamayo continued his military service, eventually attaining the rank of brigadier general and serving as director of Cuba’s civil defense. His space suit is displayed in the Museum of The Revolution in Havana.

Engineer at a wastewater treatment plant
Credit: © kittirat roekburi/Shutterstock

In 2020, at the start of the global COVID-19 pandemic, officials began testing wastewater for the virus. This tool soon helped officials track where the virus was spreading and whether cases were dropping in certain communities. What is wastewater and why is it used to track viruses? Wastewater comes from residential purposes such as bathing, laundry, and dishwashing. Most of the water in our homes is used to carry away wastes. This water, and the wastes it carries, is called sewage. Recently, scientists have employed this water for another purpose –virus tracking! It might not wear a cape, but it is helping officials prepare for outbreaks and provide information for residents on COVID-19, monkeypox, and polio. All three of these viruses are spreading in the United States.

In most U.S. cities, a piping system under the streets carries away the sewage from homes, factories, hotels, and other buildings. A system of pipes that carries sewage from buildings is called a sanitary sewerage system. Sewage has a bad odor. But more important, it contains disease-producing bacteria. Most cities have treatment plants that clean sewage water and kill the bacteria in it. The treated water can then be returned to a river, stream, or lake.

Almost all of the sewage in the United States undergoes some type of sewage treatment. Only a little of the sewage is dumped untreated into rivers. The dumping of untreated sewage causes serious problems for the environment and for cities downstream that take their water from the same rivers. Untreated sewage looks and smells foul, and it kills fish and aquatic plants.

Water treatment can also help scientists and disease experts track harmful viruses. Lately, officials have been testing wastewater for COVID-19, monkeypox, and polio. Officials are trying to control the spread of viruses to prevent epidemics. An epidemic is an outbreak of disease that attacks many people at about the same time. An epidemic may last a few hours, a few weeks, or many years. A disease that spreads throughout the world is pandemic. Public health agencies are responsible for the control of epidemics. Immunizations can prevent epidemics of some infectious diseases. Vaccines are available for COVID-19, monkeypox, and polio. Other epidemics are prevented by maintaining clean food and water supplies, or by controlling insects and other animals that spread disease. Informing people about the causes of epidemics and methods of prevention is crucial in the control of epidemics.

The next time you walk by a smelly sewer, remember not all heroes wear capes or smell good. When you see the case numbers or affected areas, tell your family and friends we have our wastewater and many dedicated scientists to thank!

Plants grown in simulated lunar soil on the left and in Apollo sample on the right, seen 16 days after planting.
Credit: Tyler Jones, UF/IFAS

Well, not exactly. Scientists recently grew plants in lunar soil for the first time in history. The lunar soil, also called moon dust, was brought back from three Apollo missions. Scientists from the University of Florida planted thale cress in the moon dust and compared the growth to materials found on Earth’s surface, such as volcanic ash. Thale cress is a small, bitter-tasting plant similar to broccoli, cauliflower, and kale. After two days, the seeds had germinated (grown). However, the plants in moon soil did not thrive compared to the plants in Earth soil after six days.

Lunar soil is very different from the soil on Earth. Soil is the mixture of minerals, organic matter, and other materials that covers most of Earth’s land. Soil is a storehouse of nutrients and the decayed remains of organisms (living things). Lunar soil is more dusty and is not made up of decayed organisms, so it does not contain as many nutrients compared to soil found on Earth. Impacts of micrometeoroids (tiny meteoroids‘) grind the surface rocks into a fine, dusty powder known as regolith. Regolith overlies all the bedrock on the moon. Because regolith forms as a result of exposure to space, the longer a rock is exposed, the thicker the regolith that forms on it.

National Aeronautics and Space Association (NASA) granted the scientists 12 grams of lunar soil for the experiment because it is precious and cannot be wasted. The soil brought back from Apollo 11 was not as strong as the soil brought back from Apollo 12 and 17. The scientists believe soil from Apollo 11 was damaged by cosmic rays and radiation from solar wind on the moon’s surface. Scientists have already started planning where they could find better moon soil where lava flow has enriched the soil.

For years, scientists have wondered whether the moon could support life. If humans were to survive on the moon permanently, they would need to grow plants for food. Although the experiment did not prove that the moon could sustain life, it gives hope that there could be vegetation on the moon someday. We are one step closer to growing an herb garden on the moon!

A particle detector helps scientists study subatomic particles. Physicists at the Fermi National Accelerator Laboratory in Batavia, Ill., use this detector to record information about particles produced in collisions between beams of protons and beams of antiprotons.
Credit: Fermilab Visual Media Services

Particle physicists are buzzing about a hefty discovery. In April 2022, researchers at the Fermi National Accelerator Laboratory (also known as Fermilab) announced that a particle called the W boson appears to have slightly more mass than expected. Their results were published in the journal Science.

Bosons are particles that transmit forces between other particles. As particles go, bosons are much less popular than their cousins the fermions, which make up matter. The W boson carries the weak nuclear force, which is involved in the decay (breakdown) of some radioactive atoms.

A particle accelerator helps scientists study electricity and the building blocks of matter. The accelerator at the Fermi National Accelerator Laboratory in Batavia, Illinois, accelerates protons to almost the speed of light in an underground tunnel, shown here.
Credit: Fermi National Accelerator Laboratory

So who cares about a chunky boson? Physicists do. Modern physics is based largely on a theory called the Standard Model. The Standard Model includes a family tree of particles and can be used to make predictions about their properties. Most of these predictions have turned out to be highly accurate. A deviation in the mass of the W boson, if confirmed, could hint at the existence of unknown particles or other revisions to the Standard Model.

Physicists study particles in giant devices called particle accelerators. As the name suggests, these devices accelerate particles to extremely high speeds. They then smash them together to study any particles created in the collision.

The experiments in question were conducted in an accelerator called the Tevatron. The device smashed positively charged particles called protons into anti-protons, their antimatter counterparts. About one in 10 million such collisions create a W boson. It took the scientists 10 years to collect enough data.

The Tevatron was shut down in 2011. But it took another 10 years to properly analyze all that data. The results suggest that the W boson is 0.1 percent heavier than expected. That’s about as much as your weight might vary if measured before and after lunch. But for extremely precise particle measurements, it may be just enough to alter our understanding of the universe.

Brontosaurus.
Credit: © Emiliano Troco

Sauropods were the most spectacular of the dinosaurs. Their long necks supported small heads that took in needles and leaves. Despite such a nutrient-poor diet, they reached sizes and lengths unparalleled in any other terrestrial (land-dwelling) animals. How—and why—did they get so large? A recent study may have discovered a lead to unraveling the physiology of these amazing animals. 

Over tens of millions of years, the arrangement of the continents has shifted through the action of plate tectonics. Geologists can trace how a location has moved over the face of Earth to determine its paleolatitude. The paleolatitude is the position of a point on the Earth’s surface in relation to the equator at a time in the distant past. Both latitude and paleolatitude are measured on a scale of 0° (the equator) to 90° (the poles). Higher latitudes experience cooler temperatures and less sunlight in winter. 

Dinosaurs reigned during the Mesozoic Era—a time of warmer climates. Despite the planet being largely ice-free, regions near the poles still faced cold winters and weeks or months without sunlight. Nevertheless, dinosaurs have been found at high paleolatitudes, including in Antarctica and Alaska. At least some of these dinosaurs remained there through the winter. 

Sauropod fossils, however, are conspicuously absent from these polar locations. No sauropod fossil has been discovered from a paleolatitude higher than about 65°. Instead, these chilly climates were strictly occupied by meat-eating theropods and some plant-eating dinosaurs called ornithischians. 

Some paleontologists (scientists who study prehistoric life) suspected the absence of fossils suggest that sauropods preferred warmer climates. But others thought that sauropods might not have fossilized well near the poles for some reason, or that the fossils are still waiting to be discovered. 

A team led by Alfio Alessandro Chiarenza of the University of Vigo in Spain analyzed the paleolatitude of all the places where sauropod fossils have been found. The team published their findings last month in the scientific journal Current Biology. They determined that the absence of sauropods at high paleolatitudes was not due to incomplete sampling. Chiarenza’s team used models of the Mesozoic climate and found that sauropods preferred savanna-type habitats. Sauropod ranges were tightly constrained by the lowest predicted temperature. 

Why didn’t (or couldn’t) sauropods brave the cold? They might have cooled down too quickly, despite their massive sizes. Many theropods—and possibly some ornithischians—had downy or hairlike feathers that could be used to keep them warm. Sauropods lacked any such insulation. Furthermore, a sauropod’s long necks and tails might have lost heat quickly when exposed to bitter-cold winds. 

Sauropods buried their eggs in the earth to keep them at a stable temperature. But this method probably would not have kept the eggs warm enough in cold climates. In contrast, theropods sat on their eggs and ornithischians covered their eggs in rotting plants. Both of these approaches could keep the eggs warm even in cold climates. 

Chiarenza’s team proposes that sauropods did not possess as high of a metabolism as theropods and ornithischians. Historically, scientists have classified animals as endothermic (“warm-blooded”) or ectothermic (“cold-blooded”). Endothermic animals tend to produce more of their own body heat, while ectothermic animals tend to rely more on their environment for heat. This is a false division, since every animal is somewhat reliant on its environment for heat. But animals classified as endothermic can usually survive in cooler temperatures. Reptiles, the classic endotherms, are concentrated near the equator. 

In many ways, this makes a lot of sense. A lower metabolism would have enabled sauropods to survive on less food. Their huge size would cause them to lose less heat to their environment, much like a well-insulated building. Growing evidence suggests that the ancestor of dinosaurs and crocodilians (a group of reptiles) had a high metabolism, but crocodilians “slowed down” when dinosaurs took over most environmental niches. A similar changed might have occurred in sauropods as well, enabling them to attain colossal sizes. Sometimes slow and steady wins the race. 

Surgeons performed an eight-hour procedure to transplant a genetically modified pig’s heart into a human on Jan. 7.
Credit: University of Maryland School of Medicine

For the first time ever, surgeons at the University of Maryland Medical Center successfully transplanted a heart from a genetically modified pig to a human. The eight-hour surgery took place on Jan. 7, 2022, in Baltimore, Maryland. The recipient was a 57-year-old man with heart disease, called arrhythmia. He was deemed too sick to receive a human heart. Scientists had altered the genes of the pig to make it more similar to humans, removing four pig genes and adding six human genes through genetic engineering.

More than 107,000 people are on waiting lists to receive organ donations in the United States. Transplanted tissues and organs replace diseased, damaged, or destroyed body parts. They can help restore the health of a person who might otherwise die or be seriously disabled. Commonly transplanted organs include the heart, lungs, kidney, and liver.

Because of the shortage of human organs, researchers are actively investigating the use of donor organs from animals. Transplanting organs from one species to another is called xenotransplantation. Use of pigs as organ donors is an especially active area of research. Pigs are already widely raised for food and leather, and their organs are about the same size as adult human organs. One major concern is preventing accidental transfer of viruses from other animals to people. Another challenge is preventing the recipient’s immune system from destroying a donor organ. If the immune system recognizes that a transplanted organ came from outside the body, the system attacks the organ as a dangerous invader. This reaction is called rejection. Doctors try to prevent rejection by choosing the best donor and prescribing immunosuppressive drugs, which are special medications to protect the transplant.

Xenotransplantation has been studied for over 60 years but is not authorized in the United States. The process of raising genetically modified animals to harvest their organs is widely debated. The Food and Drug Administration gave the surgery team an emergency authorization on Dec. 31, 2021, to conduct the transplant due to the recipient’s condition.

From the long list of people waiting to receive a lifesaving organ, 17 people die each day. This groundbreaking surgery is giving hope to many patients and their family members who are waiting on organs. However, many surgeons and experts believe it is too early to call this xenotransplantation a success.

Kenyan-born paleoanthropologist Richard Leakey and his team discovered many prehistoric human fossils at Lake Turkana, Kenya. In this photograph, he is holding near-complete fossil skulls of Homo erectus, left, and Homo habilis, right.
Credit: © Chip Hires, Gamma-Rapho/Getty Images

Famed scientist, conservationist, and politician Richard Leakey passed away aged 77 on Jan. 2, 2022 at his home outside Nairobi, Kenya. The remarkable fossils of prehistoric human ancestors discovered by Leakey and his colleagues firmly established the origins of humanity in Africa.  

Richard Erskine Frere Leakey was born on Dec. 19, 1944 in Nairobi. He was the son of distinguished British anthropologists Louis and Mary Leakey, whose excavations at Olduvai Gorge in northern Tanzania uncovered fossils of an early human ancestor they named Homo habilis. Louis Leakey argued that Homo habilis was one of the earliest types of human beings. Other scientists were skeptical, thinking that our own species likely originated in other regions.  

As a child, Richard grew up at excavation sites in Olduvai Gorge run by his parents. As a rebellious teen, however, Richard Leakey was determined to stay out of the “family business” of searching for fossils of early human ancestors. He dropped out of school and worked for a time leading safaris. While flying his own airplane over a region of northern Kenya around Lake Turkana, he recognized landscapes that likely held abundant fossils. Leading his own team of fossil hunters, Richard discovered several fossils of human ancestors, including a nearly complete skull that he recognized as Homo habilis. This species is now considered by most anthropologists to be one of the earliest types of human beings. Homo habilis lived in Africa about 2 million years ago. 

In 1984, a member of Leakey’s team, Kamoya Kimeu, found an almost complete skeleton of a young man at a site called Nariokotome near Lake Turkana that dates about 1.6 million years ago. The skeleton was classified in the species Homo erectus, a prehistoric human ancestor known from fossils first discovered in the 1800’s in Asia and later in Europe. The well-preserved fossil skeleton demonstrates that Homo erectus had a larger brain compared to Homo habilis, and first appeared in Africa. The more intelligent Homo erectus was able to adapt to new environments and migrate out of the ancestral African homeland.  

From 1968 to 1989, Richard directed the National Museums of Kenya while he and his team continued fieldwork in the Lake Turkana region, discovering many important fossils of human ancestors. From 1990 to 1994, and briefly again in 1998, he headed the Kenya Wildlife Service (KWS). In that position, he worked to eliminate the illegal killing of Kenyan elephants for their tusks, a source of ivory. In 1995, Leakey helped found a Kenyan political party called Safina, to challenge the ruling Kenya African National Union (Kanu) party.  

Since 2002, Leakey has been a professor of anthropology at the State University of New York at Stony Brook. There, he led the Turkana Basin Institute responsible for continuing fieldwork in the Lake Turkana region. In 2004 he founded the conservation organization WildlifeDirect and also returned as head of the KWS from 2015 until 2018. 

An artist’s im­pres­sion of Plan­et GJ 367b.
Credit: SPP 1992 (Patricia Klein)

Do you know someone who listens to heavy metal music? Maybe you have friends who like to wear black clothing and bang their heads to loud tunes. Perhaps you have an uncle who’s into Ozzy Osbourne or Van Halen. You may know someone who’s pretty metal, but that person is probably an absolute creampuff compared with the heavy metal planet recently discovered by German scientists.

The planet, designated GJ367b, is an exoplanet, a planet orbiting a star beyond our solar system. It orbits a red dwarf star some 31 light-years from Earth in the southern constellation Vela, the Sails. One light-year is this distance light travels in one year, about 5.88 trillion miles (9.46 trillion kilometers).

At about 3/4 the size of Earth, GJ367b is the smallest exoplanet yet discovered. But, that does not mean that it is a lightweight. The exoplanet has a density of 8 grams per cubic centimeter, compared with about 5.5  grams per cubic centimeter for Earth. This extreme density suggests that GJ367b is the most metallic planet yet discovered. It probably consists mostly of an iron core, perhaps surrounded by a thin layer of rock.

The planet’s density is not its only extreme characteristic. The planet orbits extremely close to its parent star, whipping around the red dwarf every eight hours. If you lived on GJ367b, you might be able to celebrate your birthday about three times each Earth day. You probably wouldn’t like the weather, though. Daytime temperatures reach a sizzling 1500 °C (2700 °F). That’s almost hot enough to melt the planet’s metal. In fact, GJ367b may have an atmosphere composed of evaporated rock.

That scientists were able to learn so much about such a small planet shows just how far the hunt for exoplanets has advanced. Scientists discovered GJ367b using the Transiting Exoplanet Sky Survey (TESS) telescope, announcing the discovery in December. The TESS telescope identifies exoplanets by measuring changes in a star’s light as an orbiting planet transits (passes in front of) it. Scientists hope to learn even more about this heavy metal world with the launch of the James Webb Space Telescope.

Female California condors, an endangered species, are able to reproduce without male partners, in a process known as parthenogenesis.
© Claudio Contreras, Nature Picture Library

Even after years of study, the California condor is still surprising researchers. Recently, two of the giant birds were discovered to have been born through parthenogenesis, a form of reproduction in which an unfertilized egg still hatches. Parthenogenesis is a type of asexual reproduction. Human beings and almost all other animals reproduce sexually, through mating between a male and a female. In asexual reproduction, a new organism (living thing) develops from parts of, or parts produced by, one organism. This example of parthenogenesis is particularly noteworthy because the condor is a critically endangered species. At its lowest population in 1982, only around 20 California condors were alive, in the wild and in captivity.

In 1982, researchers launched a program to save the condors, and over the next few decades, the population grew to over 500. The researchers also studied the condors in captivity. They were able to collect DNA samples from feathers and eggshells and could pay close attention to the birds’ reproductive habits. They discovered that two of the male condors did not have any genetic indication of having been fathered by the other condors in captivity. Despite having only one parent, the condors were not clones (genetically identical copies) of the mother. Rather, through fusion between the unfertilized egg and another reproductive cell in the mother’s body, the offspring end up with a unique mixture of the mother’s genetic material. Female condors can only produce male offspring through parthenogenesis, due to the way sex is determined by chromosomes among birds.

While parthenogenesis is fairly rare, it is not unheard of, even in birds. Some species of turkey and domestic pigeons also have been known to reproduce in this way. Additionally, birds are far from the only animals that can undergo parthenogenesis. Parthenogenesis has been seen in species of sharks—including the hammerhead and bamboo shark—as well as some species of snakes and lizards. Some insects, like aphids and stick insects, can also reproduce asexually. However, parthenogenesis has not been documented in mammals.

Most scientists thought that parthenogenesis only happened in populations that lacked males. For example, a female shark recently surprisingly gave birth after living 10 years in an Italian aquarium where no male sharks were kept. But the female condors had males in captivity with them. Other female condors nested and produced chicks after mating with the local males.

California condors are the largest flying land birds in North America, with a wingspan of 8 to 9 1/2 feet (2.4 to 2.9 meters). They weigh up to 23 pounds (10.4 kilograms). In the wild, condors spend much of the day resting on high perches. Condors do not build nests. Instead, their eggs are laid in caves, in holes, or among boulders. A female California condor lays just one egg every two years. Condors are powerful, graceful fliers. They can soar and glide for long distances, flapping their wings an average of only once an hour. They may search the ground for food as they fly. Like other vultures, condors eat the remains of dead animals.

The growth of urban areas has posed a major threat to condor survival. The condor’s way of life requires vast areas of open, hilly country, and urban growth destroys such habitat.