The central regions of many glittering galaxies, our own Milky Way included, harbor cores of impenetrable darkness—black holes with masses equivalent to millions, or even billions, of suns. What is more, these supermassive black holes and their host galaxies appear to develop together, or "co-evolve." Theory predicts that as galaxies collide and merge, growing ever more massive, so too do their dark hearts.
As solar panels become less expensive and capable of generating more power, solar energy is...
The rapidly melting ice sheets on the coast of West Antarctica are a potential major contributor...
A team of engineers and scientists has identified a source of electronic noise that could affect...
Scientists believe that until about 2.4 billion years ago there was little oxygen in the atmosphere. Evidence in support of this hypothesis comes from studies of sulfur isotopes preserved in the rock record. But the sulfur isotope story has been uncertain because of the lack of key information that has now been provided by a new analytical technique developed by a team of Caltech geologists and geochemists.
Nitrogen is an essential component of all living systems, playing important roles in everything from proteins and nucleic acids to vitamins. It is the most abundant element in Earth's atmosphere and is literally all around us, but in its gaseous state, N2, it is inert and useless to most organisms.
The large amount of jet fuel required to fly an airplane from point A to point B can have negative impacts on the environment and a traveler's wallet. With funding from NASA and the Boeing Company, engineers from Caltech and the Univ. of Arizona have developed a device that lets planes fly with much smaller tails, reducing the planes' overall size and weight, thus increasing fuel efficiency.
Methane-breathing microbes that inhabit rocky mounds on the seafloor could be preventing large volumes of the potent greenhouse gas from entering the oceans and reaching the atmosphere, according to a new study. The rock-dwelling microbes represent a previously unrecognized biological sink for methane and as a result could reshape scientists' understanding of where this greenhouse gas is being consumed in subseafloor habitats.
Brine shrimp, which are sold as pets known as sea-monkeys, are tiny—only about half an inch long each. With about 10 small leaf-like fins that flap about, they look as if they could hardly make waves. But get billions of similarly tiny organisms together and they can move oceans.
For decades, researchers have tried to develop broadly effective vaccines to prevent the spread of illnesses such as HIV, malaria and tuberculosis. While limited progress has been made along these lines, there are still no licensed vaccinations available that can protect most people from these devastating diseases. So what are immunologists to do when vaccines just aren't working?
For years, neuroscientists have been trying to develop tools that would allow them to clearly view the brain's circuitry in action. To get this complete picture, neuroscientists are working to develop a range of new tools to study the brain. Researchers at Caltech have developed one such tool that provides a new way of mapping neural networks in a living organism.
Lamprey—slimy, eel-like parasitic fish with tooth-riddled, jawless sucking mouths—are rather disgusting to look at, but thanks to their important position on the vertebrate family tree, they can offer important insights about the evolutionary history of our own brain development, a recent study suggests.
Imagine a balloon that could float without using any lighter-than-air gas. Instead, it could simply have all of its air sucked out while maintaining its filled shape. Such a material might be possible with a new method developed at the California Institute of Technology that allows engineers to produce a ceramic that contains about 99.9% air yet is strong enough to recover its original shape after being smashed by more than 50%.
In the typical textbook picture, volcanoes, such as those that are forming the Hawaiian islands, erupt when magma gushes out as narrow jets from deep inside Earth. But that picture is wrong, according to a new study from researchers at Caltech and the Univ. of Miami. New seismology data are now confirming that such narrow jets don't actually exist.
Researchers from Aarhus Univ. and Caltech have developed a new method for organizing molecules on the nanoscale. Inspired by techniques used for folding DNA origami, the team fabricated complicated shapes from DNA's close chemical cousin, RNA. Unlike DNA origami, whose components are chemically synthesized and then folded in an artificial heating and cooling process, RNA origami are enzymatically synthesized.
Aerosols, tiny particles in the atmosphere, play a significant role in Earth's climate, scattering and absorbing incoming sunlight and affecting the formation and properties of clouds. Currently, the effect that these aerosols have on clouds represents the largest uncertainty among all influences on climate change.
Researchers from NIST and California Institute of Technology (Caltech) have demonstrated a new design for an atomic clock that is based on a chip-scale frequency comb, or a microcomb. The microcomb clock, featured in Optica, is the first demonstration of all-optical control of the microcomb, and its accurate conversion of optical frequencies to lower microwave frequencies.
Nearly all electronics require devices called oscillators that create precise frequencies. For nearly 100 years, these oscillators have relied upon quartz crystals to provide a frequency reference, much like a tuning fork is used as a reference to tune a piano. However, future high-end navigation systems, radar systems and even possibly tomorrow's consumer electronics will require references beyond the performance of quartz.
At the nanoscale, where objects are measured in billionths of meters and events transpire in trillionths of seconds, things do not always behave as our experiences with the macro world might lead us to expect. Water, for example, seems to flow much faster within carbon nanotubes than classical physics says should be possible. Now imagine trying to capture movies of these almost imperceptibly small nanoscale movements.
Trillions of bacteria live in and on the human body; a few species can make us sick, but many others keep us healthy by boosting digestion and preventing inflammation. Although there's plenty of evidence that these microbes play a collective role in human health, we still know very little about most of the individual bacterial species that make up these communities.
Deep below the Earth's surface lies a thick, rocky layer called the mantle, which makes up the majority of our planet's volume. For decades, scientists have known that most of the lower mantle is a silicate mineral with a perovskite structure that is stable under the high-pressure and high-temperature conditions found in this region.
Researchers are trying to develop solar-driven generators that can split water, yielding hydrogen gas that could be used as clean fuel. Such a device requires efficient light-absorbing materials that attract and hold sunlight to drive the chemical reactions involved in water splitting. Semiconductors are excellent light absorbers. However, these materials rust when submerged in the type of water solutions found in such systems.
Fancy Erector Set? Nope. The elaborate fractal structure shown at left is many, many times smaller than that and is certainly not child's play. It’s the latest example of a fractal nanotruss—nano because the structures are made up of members that are as thin as 5 nm; truss because they are carefully architected structures that might one day be used in structural engineering materials.
Supernovae are incredibly energetic, dynamic events. It’s easy to imagine that they are uncommon, but the universe is a big place and supernovae are actually fairly routine. The problem with observing supernovae is knowing just when and where one is occurring and being able to point a world-class telescope at it in the hours immediately afterward, when precious data about the supernova's progenitor star is available.
Caltech researchers have found a way to make measurements that go beyond the limits imposed by quantum physics. Today, we are capable of measuring the position of an object with unprecedented accuracy, but quantum physics and the Heisenberg uncertainty principle place fundamental limits on our ability to measure.
Caltech astronomers have taken unprecedented images of the intergalactic medium (IGM)—the diffuse gas that connects galaxies throughout the universe—with the Cosmic Web Imager, an instrument designed and built at Caltech. Until now, the structure of the IGM has mostly been a matter for theoretical speculation. However, with observations from the Cosmic Web Imager, astronomers are obtaining our first 3-D pictures of the IGM.
Huntington's disease is a grim diagnosis. A hereditary disorder with debilitating physical and cognitive symptoms, the disease usually robs adult patients of their ability to walk, balance and speak. More than 15 years ago, researchers revealed the disorder's likely cause—an abnormal version of the protein huntingtin; however, the mutant protein's mechanism is poorly understood, and the disease remains untreatable.
From far away, the top of a leaf looks like one seamless surface; however, up close, that smooth exterior is actually made up of a patchwork of cells in a variety of shapes and sizes. Interested in how these cells individually take on their own unique forms, a Caltech team sought to pinpoint the shape-controlling factors in pavement cells, which are puzzle-piece-shaped epithelial cells found on the leaves of flowering plants.
In 2005, NASA's Cassini spacecraft sent pictures back to Earth depicting an icy Saturnian moon spewing water vapor and ice from fractures, known as "tiger stripes," in its frozen surface. It was big news that tiny Enceladus was such an active place. Since then, scientists have hypothesized that a large reservoir of water lies beneath that icy surface, possibly fueling the plumes.
- Page 1