Astronomy

Political campaigns are deploying AI-generated deepfake versions of politicians to reach hundreds of millions of eligible voters in India’s 2024 election – the world’s largest ever

Political campaigns are deploying AI-generated deepfake versions of politicians to reach hundreds of millions of eligible voters in India’s 2024 election – the world’s largest ever

Image: The Copernicus Sentinel-2 mission takes us over part of the Seychelles, an island republic in the western Indian Ocean.

The medicines nalmefene and naltrexone helped compulsive gamblers reduce their betting activities, trials have shown

The medicines nalmefene and naltrexone helped compulsive gamblers reduce their betting activities, trials have shown

We are all very familiar with the concept of the Earth’s magnetic field. It turns out that most objects in space have magnetic fields but it’s quite tricky to measure them. Astronomers have developed an ingenious way to measure the magnetic field of the Milky Way using polarised light from interstellar dust grains that align themselves to the magnetic field lines. A new survey has begun this mapping process and has mapped an area that covers the equivalent of 15 times the full Moon. 

Many people will remember experiments in school with iron filings and bar magnets to unveil their magnetic field. It’s not quite so easy to capture the magnetic field of the Milky Way though. The new method to measure the field relies upon the small dust grains which permeate space between the stars. The grains of dust are similar in size to smoke particles but they are not spherical. Just like a boat turning itself into the current, the dust particles’ long axis tends to align with the local magnetic field. As they do, they emit a glow in the same frequency as the cosmic background radiation and it is this that astronomers have been tuning in to. 

Infrared image of the shockwave created by the massive giant star Zeta Ophiuchi in an interstellar dust cloud. Credit: NASA/JPL-Caltech; NASA and The Hubble Heritage Team (STScI/AURA); C. R. O’Dell, Vanderbilt University

Not only do the particles glow but they also absorb starlight that passes through them just like polarising filters. The polarisation of light is familiar to photographers that might use polarising filters to darken skies and manage reflections. The phenomenon of polarisation refers to the propagation of light. As it moves through a medium it carries energy from one place to another but on the way it displays wave like characteristics. The wave nature is made up of alternating displacements of the medium through which they are travelling (imagine a wave in water). The displacement is not always the same as the direction of travel; sometimes it is parallel and at other times it is perpendicular. In polarisation, the displacement is limited to one direction only. 

In the particles in interstellar space, the polarising properties capture the magnetic field and polarise the light that travels through them revealing the details of the magnetic field. Just as they are on Earth, magnetic field lines are of crucial importance to galactic evolution. They regulate star formation, shape the structure of a galaxy and like gigantic galactic rivers, shape and direct the flow fo gas around the galaxy. 

Researchers from the Inter-University Institute for High Energies in Belgium used the PASIPHAE survey – an international collaboration to explore the magnetic field from the polarisation in interstellar dust – to start the process. They measured the polarisation of more than 1500 stars which covered an area of the sky no more than 15 times the size of the full Moon. The team then used data from the Gaia astrometry satellite and a new algorithm to map the magnetic fields in the galaxy in that part of the sky. 

This is the first time that any large scale project has attempted to map the gravitational field of the Milky Way. It will take some time to complete the full mapping but it when complete it will provide great insight not just into the magnetic field of galaxies but to the evolution of galaxies across the universe. 

Source : A first glimpse at our Galaxy’s magnetic field in 3D

The post Mapping the Milky Way’s Magnetic Field in 3D appeared first on Universe Today.

In just 2 hours, small metal robots can capture most nanoscopic plastic particles from a sample of water

In just 2 hours, small metal robots can capture most nanoscopic plastic particles from a sample of water

Boeing's Starliner capsule has been cleared for its first-ever crewed launch, a test flight scheduled to send two astronauts toward the International Space Station on May 6.

In the 1970s a young psychologist challenged a popular theory of how we acquire language, launching a fierce debate that continues to this day

Solar Sails are an enigmatic and majestic way to travel across the gulf of space. Drawing an analogy to the sail ships of the past, they are one of the most efficient ways of propelling craft in space. On Tuesday a RocketLab Electron rocket launched NASA’s new Advanced Composite Solar Sail System. It aims to test the deployment of large solar sails in low-earth orbit and on Wednesday, NASA confirmed they had successfully deployed a 9 metre sail. 

In 1886 the motor car was invented. In 1903 humans made their first powered flight. Just 58 years later, humans made their first trip into space on board a rocket. Rocket technology has changed significantly over the centuries, yes centuries. The development of the rocket started way back in the 13th Century with the Chinese and Mongolians firing rocket propelled arrows at each other. Things moved on somewhat since then and we now have solid and liquid rocket propellant, ion engines and solar sails with more technology in the wings. 

A SpaceX Falcon 9 rocket rises from its Florida launch pad to send Intuitive Machines’ Odysseus moon lander spaceward. (NASA via YouTube)

Solar sails are of particular interest because they harness the power of sun, or star light to propel probes across space. The idea isn’t knew though, Johannes Kepler (of planetary motion fame) first suggested that sunlight could be used to push spacecraft in the 17th Century in his works entitled ‘Somnium’. We had to wait until the 20h Century though before Russian scientist Konstantin Tsiolkovsky outlined the principle of how solar sails might actually work. Carl Sagan and other members of the Planetary Society start to propose missions using solar sails in the 70’s and 80’s but it wasn’t until 2010 that we saw the first practical solar sail vehicle, IKAROS.

Image of the fully deployed IKAROS solar sail, taken by a separation camera. Credit: JAXA

The concept of solar sails is quite simple to understand, relying upon the pressure of sunlight. The sails are angled such that photons strike the reflective sail and bounce off it to push the spacecraft forward. It does of course take a lot of photons to accelerate a spacecraft using light but slowly, over time it is a very efficient propulsion system requiring no heavy engines or fuel tanks. This reduction of mass makes it easier for solar sails to be accelerated by sunlight but the sail sizes have been limited by the material and structure of the booms that support them. 

NASA have been working on the problem with their Next Generation Solar Sail Boom Technology. Their Advanced Composite Solar Sail System uses a CubeSat built by NanoAvionics to test a new composite boom support structure. It is made from flexible polymer and carbon fibre materials to create a stiffer, lighter alternative to existing support structure designs. 

On Wednesday 24 April, NASA confirmed that the CubeSat has reached low-Earth orbit and deployed a 9 metre sail. They are now powering up the probe and establishing ground contract. It took about 25 minutes to deploy the sail which spans 80 square metres. If the conditions are right, it may even be visible from Earth, possibly even rivalling Sirius in brightness. 

Source : Solar Sail CubeSat Has Deployed from Rocket

The post NASA’s New Solar Sail Has Launched and Deployed appeared first on Universe Today.

The neurons in wasp brains that help them recognise hive mates are similar to those in the brains of primates, including humans

The neurons in wasp brains that help them recognise hive mates are similar to those in the brains of primates, including humans

Two Russian cosmonauts completed a spacewalk at the International Space Station on April 25, wrapping up all of their tasks with time to spare, including the deployment of a radar that they began last year.

A new theory suggests that NASA's Curiosity rover is "burping" the surface of the Red Planet, releasing methane trapped beneath a salty crust.

The supermassive black holes at the centres of galaxies may capture smaller black holes. Not only does this prove a place for the small black holes to grow, it also makes the supermassive ones look even bigger and brighter

The supermassive black holes at the centres of galaxies may capture smaller black holes. Not only does this prove a place for the small black holes to grow, it also makes the supermassive ones look even bigger and brighter

The EPA has released four new pollution rules, most focusing on coal-fired power, as the final pieces of Biden’s push to clean up the power sector

Get ready space fans, Lego is about to launch two sets that can take you from the moon to edge of our cosmic neighborhood: Lego Icons NASA Artemis Space Launch System and Lego Art Milky Way Galaxy.

People understand how saving tropical forests is good for the planet, but temperate forests are equally indispensable in fighting climate change