The jets emanating from Centaurus A are over a million light years long. These jets of streaming plasma, expelled by a giant black hole in the center of this spiral galaxy, light up this composite image of Cen A. Exactly how the central black hole expels infalling matter remains unknown. After clearing the galaxy, however, the jets inflate large radio bubbles that likely glow for millions of years. If energized by a passing gas cloud, the radio bubbles can even light up again after billions of years. X-ray light is depicted in the featured composite image in blue, while microwave light is colored orange. The base of the jet in radio light shows details of the innermost light year of the central jet.
A mere 2.5 million light-years away the Andromeda Galaxy, also known as M31, really is just next door as large galaxies go. So close and spanning some 260,000 light-years, it took 11 different image fields from the Galaxy Evolution Explorer (GALEX) satellite’s telescope to produce this gorgeous portrait of the spiral galaxy in ultraviolet light. While its spiral arms stand out in visible light images of Andromeda, the arms look more like rings in the GALEX ultraviolet view, a view dominated by the energetic light from hot, young, massive stars. As sites of intense star formation, the rings have been interpreted as evidence Andromeda collided with its smaller neighboring elliptical galaxy M32 more than 200 million years ago. The large Andromeda galaxy and our own Milky Way are the most massive members of the local galaxy group.
Have been reading “The Fabric of Reality” for several months now It takes me awhile to digest things, and I have a 2 year old, but also I can’t sleep after I read a chapter, and I can’t stop once I start (so I tend to tackle it when I feel up to it).
Last night I finished the “Quantum Computers” chapter. Like the previous chapters it is mind blowing. I already knew a little bit about quantum computers, but there was a revelation that just blew me away. Here’s my layman’s (probably incorrect in some way) takeaway.
There are an infinite amount of you in the multi-verse, but you just can’t interact with them. In the infinite amount of you, you just need to be able to interact with the ones that are doing the same thing as you to, quantum computers allow you to do that. They allow you to use interference that differentiates the subtle differences universe (like a proton interacting with a half-silvered mirror in one universe, and not in the other) to process computation across universes.
Here’s the chapter: https://archive.org/details/TheFabricOfReality/page/n141/mode/2up
But, the point is that it stands to be falsified that there are an infinite amount of you that you can interact with through a computer. You can leverage an infinite amount of yourself to solve problems.
It also has profound implications for the internet (as you’ve probably heard before)—because the internet relies on cryptography that uses classical model physics for security. All private data on computers is protected behind a few large easy to multiply, but hard to factor numbers. It’s highly probable that in the next decade or so Shor’s algorithm will be used to factor some big number in minutes that would have taken all the classical computers on earth a million years.
Scientists have identified the presence of a non-tobacco plant in ancient Maya drug containers for the first time.
The Washington State University researchers detected Mexican marigold (Tagetes lucida) in residues taken from 14 miniature Maya ceramic vessels.
Originally buried more than 1,000 years ago on Mexico’s Yucatán peninsula, the vessels also contain chemical traces present in two types of dried and cured tobacco, Nicotiana tabacum and N. rustica. The research team, led by anthropology postdoc Mario Zimmermann, thinks the Mexican marigold was mixed with the tobacco to make smoking more enjoyable.
The discovery of the vessels’ contents paints a clearer picture of ancient Maya drug use practices. The research, which was published today in Scientific Reports, also paves the way for future studies investigating other types of psychoactive and non-psychoactive plants that were smoked, chewed, or snuffed among the Maya and other pre-Colombian societies.
The Milky Way houses 8,292 recently discovered stellar streams—all named Theia. But Theia 456 is special.
A stellar stream is a rare linear pattern—rather than a cluster—of stars. After combining multiple datasets captured by the Gaia space telescope, a team of astrophysicists found that all of Theia 456’s 468 stars were born at the same time and are traveling in the same direction across the sky.
“Most stellar clusters are formed together,” said Jeff Andrews, a Northwestern University astrophysicist and member of the team. “What’s exciting about Theia 456 is that it’s not a small clump of stars together. It’s long and stretched out. There are relatively few streams that are nearby, young and so widely dispersed.”
Andrews presented this research during a virtual press briefing at the 237th meeting of the American Astronomical Society. “Theia 456: A New Stellar Association in the Galactic Disk” took place today (Jan. 15) as a part of a session on “The Modern Milky Way.”
This fantastic skyscape lies near the edge of NGC 2174 a star forming region about 6,400 light-years away in the nebula-rich constellation of Orion. It follows mountainous clouds of gas and dust carved by winds and radiation from the region’s newborn stars, now found scattered in open star clusters embedded around the center of NGC 2174, off the top of the frame. Though star formation continues within these dusty cosmic clouds they will likely be dispersed by the energetic newborn stars within a few million years. Recorded at infrared wavelengths by the Hubble Space Telescope in 2014, the interstellar scene spans about 6 light-years. Scheduled for launch in 2021, the James Webb Space Telescope is optimized for exploring the Universe at infrared wavelengths.
Gravitational-wave astronomy is still in its infancy. LIGO and other observatories have opened a new window on the universe, but their gravitational view of the cosmos is limited. To widen our view, we have the North American Nanohertz Observatory for Gravitational Waves (NANOGrav).
Gravitational waves are created by the motion of massive objects. Most of the gravitational waves we’ve detected come from the merger of black holes. In their last moments, binary black holes orbit each other very quickly, producing rapid and strong gravitational waves. But most of the gravitational waves rippling through the universe are neither rapid nor strong. They are the faint echoes of orbiting black holes that aren’t about to merge. Their slow orbits create a background of gravitational waves. A single wave from one of these sources can take years to make a complete cycle.
It’s stars versus dust in the Carina Nebula and the stars are winning. More precisely, the energetic light and winds from massive newly formed stars are evaporating and dispersing the dusty stellar nurseries in which they formed. Located in the Carina Nebula and known informally as Mystic Mountain, these pillar’s appearance is dominated by the dark dust even though it is composed mostly of clear hydrogen gas. Dust pillars such as these are actually much thinner than air and only appear as mountains due to relatively small amounts of opaque interstellar dust. About 7,500 light-years distant, the featured image was taken with the Hubble Space Telescope, digitally reprocessed by an industrious amateur, and highlights an interior region of Carina which spans about three light years. Within a few million years, the stars will likely win out completely and the entire dust mountain will be destroyed.
NASA declared the Mars digger dead Thursday after failing to burrow deep into the red planet to take its temperature.
Scientists in Germany spent two years trying to get their heat probe, dubbed the mole, to drill into the Martian crust. But the 16-inch-long (40-centimeter) device that is part of NASA’s InSight lander couldn’t gain enough friction in the red dirt. It was supposed to bury 16 feet (5 meters) into Mars, but only drilled down a couple of feet (about a half meter).
Following one last unsuccessful attempt to hammer itself down over the weekend with 500 strokes, the team called it quits.
“We’ve given it everything we’ve got, but Mars and our heroic mole remain incompatible,” said the German Space Agency’s Tilman Spohn, the lead scientist for the experiment.
Like salsa verde on your favorite burrito, a green aurora slathers up the sky in this 2017 June 25 snapshot from the International Space Station. About 400 kilometers (250 miles) above Earth, the orbiting station is itself within the upper realm of the auroral displays. Aurorae have the signature colors of excited molecules and atoms at the low densities found at extreme altitudes. Emission from atomic oxygen dominates this view. The tantalizing glow is green at lower altitudes, but rarer reddish bands extend above the space station’s horizon. The orbital scene was captured while passing over a point south and east of Australia, with stars above the horizon at the right belonging to the constellation Canis Major, Orion’s big dog. Sirius, alpha star of Canis Major, is the brightest star near the Earth’s limb.
NGC 247 is a beautiful spiral galaxy that we see almost edge-on. It’s smaller than the Milky Way, but it contains some bright nurseries—dense gaseous regions where new stars form. Its most unusual feature, though, is a dark “void” on one side of the galaxy’s core, which looks like a hole has been punched through the disk. The region contains a few old, faint stars but almost no young, bright ones.
Initially, astronomers suggested that the void might have been caused by gravitational interactions with part of another galaxy. More recent research suggests the void could have formed when a blob of dark matter—theoretical, so far, undetected material that is estimated to account for 27 percent of the universe—plunged through the disk like a rock through tissue paper. The impact would have scattered stars and blown away the gas and dust for making more stars.
Or there could be an even weirder explanation, says Lacki.“The SETI community hasn’t paid much attention to it, but if you have extraterrestrial intelligences that build Dyson Spheres and have interstellar travel, what would that society look like?” he asks. “They might start by building a sphere around their own star, then expand to nearby stars, building a Dyson Sphere around each star that they arrive at. That might look like a hole in a galaxy that grows as they expand. NGC 247 reminds me of that. The hole is probably natural, but we can’t be absolutely sure.”
The Exotica Catalog lists a few other odd galaxies that could be home to vast civilizations. “We know that the universe is capable of giving rise to an intelligent, technologically capable species,” says Siemion. “And if you think even further, one could imagine that extremely advanced technologies—millions, maybe billions, of years more advanced than ours—might even have capabilities that would manifest on cosmological scales.”
“We are building new telescopes that will make looking for these things easier,” says Shostak. The Vera C. Rubin Observatory, under construction in Chile, will in the next few years be able to observe the entire sky every few nights—over and over—and therefore show anything that changes.
With new instruments and the imagination required for all scientific discovery, astronomers may find the advanced civilizations Frank Drake once dreamed of—or the most mundane of explanations for the puzzles presented by the universe.
We review the literature about reaching agreement in quantum networks, also called quantum consensus. After a brief introduction to the key feature of quantum computing, allowing the reader with no quantum theory background to have minimal tools to understand, we report a formal definition of quantum consensus and the protocols proposed. Proposals are classified according to the quantum feature used to achieve agreement.
In cosmic brush strokes of glowing hydrogen gas, this beautiful skyscape unfolds across the plane of our Milky Way Galaxy and the center of the northern constellation Cygnus the Swan. The featured image spans about six degrees. Bright supergiant star Gamma Cygni (Sadr) to the upper left of the image center lies in the foreground of the complex gas and dust clouds and crowded star fields. Left of Gamma Cygni, shaped like two luminous wings divided by a long dark dust lane is IC 1318, whose popular name is understandably the Butterfly Nebula. The more compact, bright nebula at the lower right is NGC 6888, the Crescent Nebula. Some distance estimates for Gamma Cygni place it at around 1,800 light-years while estimates for IC 1318 and NGC 6888 range from 2,000 to 5,000 light-years.
The news that NASA will extend the InSight mission on Mars for two years, taking it through December of 2022, is not surprising, given the data trove the mission team has collected through operation of the mission seismometer. A live asset on Mars also deepens our knowledge of the planet’s atmosphere and magnetic field, all reasons enough for pushing for another two years. But the extension of the Juno mission to Jupiter deserves more attention than it’s getting, given that Juno’s remit will be expanded deep into the Jovian system.
A gorgeous spiral galaxy some 100 million light-years distant, NGC 1309 lies on the banks of the constellation of the River (Eridanus). NGC 1309 spans about 30,000 light-years, making it about one third the size of our larger Milky Way galaxy. Bluish clusters of young stars and dust lanes are seen to trace out NGC 1309’s spiral arms as they wind around an older yellowish star population at its core. Not just another pretty face-on spiral galaxy, observations of NGC 1309’s recent supernova and Cepheid variable stars contribute to the calibration of the expansion of the Universe. Still, after you get over this beautiful galaxy’s grand design, check out the array of more distant background galaxies also recorded in this sharp, reprocessed, Hubble Space Telescope view.
Mars, once thought to be a static, dusty landscape, is ever changing. It wasn’t until NASA’s Mars Reconnaissance Orbiter (MRO) showed up that we observed shifting dunes, seasons coming and going, and dust devils swirling across the planet. The spacecraft recently marked its 15th anniversary in orbit around our neighboring world, where it has used a suite of four science instruments and three cameras to catalogue a diverse array of geologic features. “Before we had never had enough resolution over a long-enough period to see changes on the surface,” says Richard Zurek, MRO’s project scientist at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif. “Today we can see that Mars is dynamic.”