|Mercury seen at the top left with the Sun in the background|
|2017 - Jupiter's south pole, taken by NASA's Juno spacecraft from an altitude of 32,000 miles|
|2017 - Jupiter's massive storms and clouds of ammonia and ice taken by Juno every 53 days on orbit|
|2017 - Earth as a tiny speck, taken from between Saturn's rings by Cassini|
|2017 - A hurricane over Saturn's north pole, taken by NASA's Cassini spacecraft|
|Rocks on Mars|
|Saturn's rings from Cassini's final photos. Up-close look at “propellers,” or structures that look like gaps in the rings caused by one of Saturn’s 62 moons|
|Pismis 24-1 at the heart of NGC 6357. 6,500 light-years away from Earth.|
The six most common elements of life on Earth (including more than 97% of the mass of a human body) are carbon, hydrogen, nitrogen, oxygen, sulphur and phosphorus. The current stellar chemistry measurements use a spectrograph that senses infrared light – the APOGEE (Apache Point Observatory Galactic Evolution Experiment) spectrograph, mounted on the 2.5-meter Sloan Foundation Telescope at Apache Point Observatory in New Mexico.
“It’s a great human interest story that we are now able to map the abundance of all of the major elements found in the human body across hundreds of thousands of stars in our Milky Way,” Jennifer Johnson of Ohio State University said in a press release. “This allows us to place constraints on when and where in our galaxy life had the required elements to evolve, a sort ‘temporal Galactic habitable zone.’”
|2015 - Westerlund 2, a giant cluster of about 3,000 stars in a stellar breeding ground known as Gum 29, located 20,000 light-years from Earth.|
|2016 - Murray Buttes on Mars (Curiosity Rover has driven about 8.76 miles in the four years that it has been operating)|
"Enter Mauna Loa: The barren Hawaiian volcano is about as Martian as Earth terrain gets, and NASA's 36-foot-wide domed habitat is a good approximation of the kind of thing we could set up on Mars. Previous simulations on Mauna Loa have maxed out at eight months long. One Russian simulation in another location kept astronauts in isolation for a year and a half, but they were essentially trapped inside a "spacecraft" with no way out — they didn't venture onto the "alien" surface, as the astronauts in the Hawaiian experiment did."
|2006 - Mars dunes in winter, bright areas could be carbon dioxide or water frost|
|2006 - Mars north polar layered deposits, ice-rich or dust-rich layers and unconformities|
"If the universe was full of particles from families with very heavy or zero-mass Higgs bosons, then gravity between particles would be too strong or too weak for atoms to form. Only one family would have a Higgs boson just light enough to let planets and people develop – the Goldilocks amount of gravity. As a result, our familiar standard model of particles – which has the lightest possible non-zero-mass Higgs – reigns supreme. That’s one step towards solving the weak-gravity problem. The next step comes from the team’s observation that the equation for gravity between particles can be fine-tuned by adjusting the number of particle sectors.
The team calculated that about 1016 particle families results in a small value for gravity’s strength. If you combine the effect of large numbers of particles on the gravity equation and the reheatons favouring light Higgs bosons, you get gravity just weak enough for playing basketball instead of collapsing into a singularity, says Cohen."
Wang and his colleagues paired the famous cat paradox with another tenet of quantum mechanics: quantum entanglement, the phenomenon Einstein referred to as “spooky action at a distance." When two interacting subatomic particles become entangled, any change induced in one will be inflicted upon the other, no matter how distantly they're separated.
"Boeing, the aerospace giant, and SpaceX, the upstart founded by tech billionaire Elon Musk, are slated to start flying NASA astronauts to the International Space Station by late 2017 or early 2018. They’ll fly in new spacecraft—Boeing’s Starliner and SpaceX’s Dragon—that in many ways resemble the capsules flown during the Apollo era, but are far more advanced. There is also a sporty little spaceplane called the Dream Chaser under development by the Sierra Neveda Corp., to take cargo to the space station; a monster rocket known as the Space Launch System being built by Boeing, and others, for NASA; a new deep space capsule called Orion that Lockheed Martin is building for NASA; and a replacement for the workhorse Atlas V rocket called Vulcan that’s under development by the United Launch Alliance, a joint venture of Lockheed Martin and Boeing."
|1972 - Apollo 17 moonbuggy fender repaired with duct tape.|
"The B2FH paper, named after the initials of the authors of the paper, Margaret Burbidge, Geoffrey Burbidge, William Fowler, and Fred Hoyle, is a landmark paper of stellar physics published in Reviews of Modern Physics in 1957. The formal title of the paper is Synthesis of the Elements in Stars, but the article is generally referred to only as "B2FH". The paper comprehensively outlined and analyzed several key processes that might be responsible for the synthesis of elements in nature and their relative abundance, and it is credited with originating what is now the theory of stellar nucleosynthesis."
"The Eta Aquarid meteor shower is usually active between April 19 and May 28 every year. It tends to peak around May 6 or May 7. The Eta Aquarids is one of two meteor showers created by debris from Comet Halley. The Earth passes for a second time through Halley's path around the Sun in October. This creates the Orionid meteor shower, which peaks around October 20. Halley takes around 76 years to make a complete revolution around the Sun. It will next be visible from Earth in 2061."
"SpaceX is planning to send Dragons to Mars as early as 2018," the company said via Facebook Wednesday. "These missions will help demonstrate the technologies needed to land large payloads propulsively on Mars." In a statement about the collaboration with SpaceX, Newman says a new and broad consensus is emerging that calls for sending astronauts to Mars in the 2030s.
SpaceX's Musk adds via Twitter that the new Dragon 2 craft is "designed to be able to land anywhere in the solar system." Few details were announced along with the news of SpaceX and NASA's Mars collaboration; more details are likely to come out this fall. For now, a SpaceX representative says that while the company will fund the mission, NASA will give technical support — along with access to the Deep Space Network for communications.
"Larger stars have more fuel, but they have to burn (fuse) it faster in order to maintain equilibrium. Because thermonuclear fusion occurs at a faster rate in massive stars, large stars use all of their fuel in a shorter length of time. This means that bigger is not better with respect to how long a star will live. A smaller star has less fuel, but its rate of fusion is not as fast. Therefore, smaller stars live longer than larger stars because their rate of fuel consumption is not as rapid."
"Most longer-lasting stars that are fainter than the sun are just too dim to view without telescopic aid. At the end of a stars life, when the supply of available hydrogen is nearly exhausted, it swells up and brightens. Many stars that are visible to the naked eye are in this stage of their life cycles because this bias brings them preferentially to our attention. They are, on average, a few hundred million years old and slowly coming to the end of their lives."
|The surface of Saturn and its rings, imaged by NASA’s Cassini orbiter|
"What is a solar storm? The sun is constantly shooting out particle streams into space in the form of a solar wind. As a giant storm explodes forth, these winds increase in intensity, compressing Jupiter's magnetosphere -- the area surrounding the planet in space where Jupiter exerts the greatest magnetic force. The boundary can move with the wind 1.25 million miles through space. This is essentially the trigger that creates the X-rays in the planet's Northern Lights."
"Ruff and Farmer found the "micro-digitate silica structures" in a geyser field known as El Tatio, and similar features have been found near Yellowstone's hot springs as well as in New Zealand's Taupo volcanic zone. In both of those places, the silica bears the fossilized fingerprints of microbial life.
The two scientists have hypothesized that the Atacama structures are the remains of bacterial activity, and they're looking for microbial biosignatures. If those biosignatures turn up, it could make Gusev crater area a prime target to look for evidence of past life on Mars."
"Astronomers have long suspected that the moon formed after a small, proto-planet, called Theia, crashed into Earth, knocking a chunk of rock into Earth's orbit. New research by scientists at the University of California Los Angeles suggests that Theia didn't merely sideswipe Earth, but instead fused with our planet, forming a new Earth and also the moon.
The new evidence comes from an analysis of oxygen isotopes from both volcanic rocks and lunar rocks that were brought to Earth as part of the Apollo missions. The astronomers found that the isotopes share a unique fingerprint, something that could only happen if matter from Theia and Earth thoroughly mixed together in a head-on collision."
"The solar system appears to have a new ninth planet ["Planet Nine", "Planet X" or "Nibiru"]. Today, two scientists announced evidence that a body nearly the size of Neptune—but as yet unseen—orbits the sun every 15,000 years. During the solar system’s infancy 4.5 billion years ago, they say, the giant planet was knocked out of the planet-forming region near the sun. Slowed down by gas, the planet settled into a distant elliptical orbit, where it still lurks today.
Batygin and Brown inferred its presence from the peculiar clustering of six previously known objects that orbit beyond Neptune. They say there’s only a 0.007% chance, or about one in 15,000, that the clustering could be a coincidence. Instead, they say, a planet with the mass of 10 Earths has shepherded the six objects into their strange elliptical orbits, tilted out of the plane of the solar system."
December 21, 2015: Today, Elon Musk’s SpaceX successfully landed its Falcon 9 rocket, the first time in five tries that the company was able to bring the first stage of its launch vehicle back to Earth. The four previous attempts all ended in crashes, some in spectacular fashion.
According to SpaceX, being able to land a rocket after launch—and then be able to use it again—is an essential step forward in making space missions of all kinds more affordable.
"If one can figure out how to effectively reuse rockets just like airplanes, the cost of access to space will be reduced by as much as a factor of a hundred," Musk says on SpaceX’s website. "A fully reusable vehicle has never been done before. That really is the fundamental breakthrough needed to revolutionize access to space."
"The problem isn’t NASA per se, but that it’s a government agency. It has to dance with both Congress and the White House, and they can be recalcitrant partners. Once a project gets big enough, for example, special interests chime in. Senators and Representatives look to help out their own states and districts by adding layers of bureaucracy and pork to the projects, then protect whatever they get. Also, the White House and Capitol Hill don’t always agree on what’s needed or how to get there, adding more confusion, and the inevitable sparring over the annual NASA budget tends to make things worse."
"Our main motivation was understanding the Earth's place in the context of the rest of the universe," said study author Peter Behroozi of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, "Compared to all the planets that will ever form in the universe, the Earth is actually quite early."
Kepler's planet survey indicates that Earth-sized planets in a star's habitable zone, the perfect distance that could allow water to pool on the surface, are ubiquitous in our galaxy. Based on the survey, scientists predict that there should be 1 billion Earth-sized worlds in the Milky Way galaxy at present, a good portion of them presumed to be rocky. That estimate skyrockets when you include the other 100 billion galaxies in the observable universe.
The data show that the universe was making stars at a fast rate 10 billion years ago, but the fraction of the universe's hydrogen and helium gas that was involved was very low. Today, star birth is happening at a much slower rate than long ago, but there is so much leftover gas available that the universe will keep cooking up stars and planets for a very long time to come.
"Scientists are interested in studying comets because they are rich in building blocks and elements essential for life: organic molecules and water. Rosetta’s Italian-led visible and infrared imaging spectrometer, or VIRTIS sensor, detected organic compounds similar to carboxylic acids that make up amino acids, which combine to form proteins.
Experts suspected Rosetta would find such material on comet 67P after discovering amino acids in meteorites that fell to Earth, but Rosetta made the first measurement of the polymer-like compounds on a comet. The signal detected by Rosetta indicates complex organic molecules were abundant in the material that formed the comet’s nucleus, according to a press release issued by the National Institute for Astrophysics in Italy.
“The formation of such compounds requires the presence of ices of volatile molecules such as methanol, methane or carbon monoxide, which only freeze at very low temperatures,” said Fabrizio Capaccioni, principal investigator for the VIRTIS instrument at the Institute for Space Astrophysics and Planetology in Rome."
"Volunteers marked it out as unusual in 2011, right after the program started: a star whose light curves seemed to dip tremendously at irregular intervals. At one point, about 800 days into the survey, the star’s brightness dropped by 15 percent. Later, around day 1,500, it dropped by a shocking 22 percent. Whatever was causing the dips, it could not have been a planet — even a Jupiter-sized planet, the biggest in our solar system, would only dim this star by 1 percent as it transited across, Slate reported. (The Kepler telescope was badly damaged in 2013, so the researchers don’t have data from more recent dips, if there were any)."
UPDATE: Marengo and Co.'s work didn't actually rule out an alien megastructure, but it did rule out other, more likely explanations — like massive planetary or asteroid collisions. Looking at the star in infrared light didn't reveal the hot dust one would expect from such violent activity. That makes the most likely (non-alien) explanation a set of cold comets — ones that have been orbiting the planet for a while, causing different levels of dimming based on their assorted sizes and transit periods.
"[KIC 8462852] is a very strange star," Marengo said in a statement. "It reminds me of when we first discovered pulsars. They were emitting odd signals nobody had ever seen before, and the first one discovered was named LGM-1 after 'Little Green Men.'”
Red auroras, which occur much higher in the atmosphere than the more typical green auroras, are not entirely understood by space weather scientists. “Some researchers believe the red lights are linked to low energy electrons from the sun, which move too slowly to penetrate deeply into the atmosphere,” says spaceweather.com. “When such electrons recombine with oxygen ions in the upper atmosphere, red photons are emitted. At present, space weather forecasters cannot predict when this will occur.”
"Some of the earliest missions to Mars revealed a planet with a watery past. Pictures beamed back to Earth in the 1970s showed a surface crossed by dried-up rivers and plains once submerged beneath vast ancient lakes. Earlier this year, Nasa unveiled evidence of an ocean that might have covered half of the planet’s northern hemisphere in the distant past. For now, researchers are focused on learning where the water comes from. A possibility, and one favoured by McEwen, is that salts on the Martian surface absorb water from the atmosphere until they have enough to run downhill. The process, known as deliquescence, is seen in the Atacama desert, where the resulting damp patches are the only known place for microbes to live."
"Take a look up at the night sky Sunday (September 27) after dusk to get a look at the supermoon eclipse. This is the moment when a total lunar eclipse coincides with a so-called supermoon - a full moon that's at the closest point of its orbit to Earth, making it appear bigger and brighter than usual. A supermoon eclipse hasn't been seen since 1982 and won't happen again until 2033. This weekend's eclipse marks the end of a tetrad, or series of four total lunar eclipses set about six months apart. This series began in April 2014. The 21st century will see eight of these tetrads, an uncommonly good run. From 1600 to 1900, there were none."
Bill Nye: "Just keeping the NASA budget growing with inflation, we'll have people orbiting Mars by 2033."
"They've determined that the recently discovered EGS8p7 galaxy is a whopping 13.2 billion years old, making it both the farthest known galaxy to date and just 600 million years younger than the universe as we know it. Theoretically, it shouldn't be possible to see the galaxy at all -- in EGS8p7's era, space was supposed to be full of neutral hydrogen clouds that absorbed radiation and made galaxies invisible to later observers."
"The latest surveys of the universe indicate that only 4% of it is made of ordinary matter. Nearly 23% is made of dark matter, which some physicists suspect consists of wispy subatomic particles that may someday be caught in a detector. And the remaining 73% is made up of an energy that is causing the universe to expand at an ever-increasing rate. Scientists call it 'dark energy,' and they have no idea what it is."
"When the density of matter reaches gargantuan proportions (more than about 1,050 kilograms per cubic meter) inside a black hole, torsion manifests itself as a force that counters gravity. This prevents matter from compressing indefinitely to reach infinite density, so there is no singularity. Instead, says Nikodem Poplawski, matter rebounds and starts expanding again."
"The view will be most dramatic on the 20th, when the two planets and the moon will be bunched closely enough to be covered by an outstretched fist. While they look to be bumping into one another, they are actually far apart. The moon is closest to us, just 247,000 miles away. Venus is 56 million miles from Earth, and Jupiter is 10 times farther out at just over 550 million miles.
Sky & Telescope Contributing Editor Fred Schaaf points out that this current string of Venus-Jupiter conjunctions closely resembles a similar series between the years 3 and 2 B.C. It has been suggested that their joint appearance might have been what came to be known as the Star of Bethlehem."
"The unmanned Orion capsule will orbit the Earth twice, once at a distance of 3,600 miles above the Earth, before re-entering Earth’s atmosphere at a speed of 20,000 miles per hour and at temperatures of 4,000 degrees Fahrenheit. Returning from Mars, the future capsules will have to withstand 6,000 degrees. NASA’s Orion project hopes to put humans on the red planet sometime before 2040."
"Official investigators from around the world hope that scientific curiosity, and concerns about air safety, will eventually overcome the U.S. government stalemate. They recognize that UFOs provide a challenge to our current scientific paradigm, since the "extraterrestrial hypothesis" must be considered along with others. For this reason, a taboo against the topic remains fixed."
Newton's laws of motion are three physical laws that, together, laid the foundation for classical mechanics. They describe the relationship between a body and the forces acting upon it, and its motion in response to those forces:
- "Law of Inertia": Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.
- Law of Dynamics: The relationship between an object's mass m, its acceleration a, and the applied force F is F=ma. Acceleration and force are vectors (as indicated by their symbols being displayed in slant bold font); in this law the direction of the force vector is the same as the direction of the acceleration vector. Said another way: The change of momentum of a body is proportional to the impulse impressed on the body, and happens along the straight line on which that impulse is impressed.
- Law of Opposites: To every action there is always opposed an equal reaction: or the mutual actions of two bodies upon each other are always equal, and directed to contrary parts.
The four laws of thermodynamics define fundamental physical quantities (temperature, energy, and entropy) that characterize thermodynamic systems. The laws describe how these quantities behave under various circumstances, and forbid certain phenomena (such as perpetual motion). The four laws of thermodynamics are:
- Zeroth law of thermodynamics: If two systems are in thermal equilibrium independently with a third system, they must be in thermal equilibrium with each other. This law helps define the notion of temperature.
- First law of thermodynamics: When energy passes, as work, as heat, or with matter, into or out from a system, its internal energy changes in accord with the law of conservation of energy. Equivalently, perpetual motion machines of the first kind are impossible.
- Second law of thermodynamics: In a natural thermodynamic process, the sum of the entropies of the interacting thermodynamic systems increases. Equivalently, perpetual motion machines of the second kind are impossible.
- Third law of thermodynamics: The entropy of a system approaches a constant value as the temperature approaches absolute zero. With the exception of non-crystalline solids (glasses) the entropy of a system at absolute zero is typically close to zero, and is equal to the logarithm of the multiplicity of the quantum ground states.