Earth’s Old Trees Keep A Record of Powerful Solar Storms

A solar flare erupts on the Sun. Credit: NASA/GSFC/SDO

Most of the time the Sun is pretty well-mannered, but occasionally it’s downright unruly. It sometimes throws extremely energetic tantrums. During these events, a solar flare or a shock wave from a coronal mass ejection (CME) accelerates protons to extremely high velocities. These are called Solar Particle Events or Solar Proton Events (SPEs).

However, the exact timing of these events can be difficult to ascertain. New research has determined the date of one of the most powerful SPEs to strike Earth during the Holocene.

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New Supercomputer Simulation Explains How Mars Got Its Moons

Computer simulation showing the origin of the Martian moons. Credit: NASA's Ames Research Center

Earth and Mars are the only two rocky planets in the solar system to have moons. Based on lunar rock samples and computer simulations, we are fairly certain that our Moon is the result of an early collision between Earth and a Mars-sized protoplanet called Theia. Since we don’t have rock samples from either Martian moon, the origins of Deimos and Phobos are less clear. There are two popular models, but new computer simulations point to a compromise solution.

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The First Close-Up Picture of Star Outside the Milky Way

WOH G64 is a massive red supergiant star in the Large Magellanic Cloud. Thanks to the ESO's Very Large Telescope Interferometer, this is the first close-up picture of a star in another galaxy. Image Credit: ESO/K. Ohnaka et al.

Like a performer preparing for their big finale, a distant star is shedding its outer layers and preparing to explode as a supernova.

Astronomers have been observing the huge star, named WOH G64, since its discovery in the 1970s. It’s one of the largest known stars, and also one of the most luminous and massive red supergiants (RSGs). The star is surrounded by an envelope of expelled star-stuff, which could indicate it’s getting ready to explode.

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Here’s What We Know About Earth’s Temporary Mini-Moon

2024-PT5

For a little over a month now, the Earth has been joined by a new ‘mini-moon.’ The object is an asteroid that has been temporarily accompanying Earth on its journey around the Sun. By 25th November it will have departed but before then, astronomers across the world have been turning their telescopes to study it. A new paper of 2024 PT5 reveals its basaltic nature – similar to volcanic rocks on Earth – with a composition that makes it similar to lunar material. There have been many close encounters to Earth allowing many of its secrets to be unveiled.

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New Study Suggests Black Holes Get their “Hair” from their Mothers

This artist’s impression of a supermassive black hole and accretion disk, along with a relativistic jet emanating from its poles. Credit & ©: ESO/L. Calçada

Despite decades of study, black holes are still one of the most puzzling objects in the Universe. As we know from Einstein’s Theory of General Relativity, the gravitational force of these stellar remnants alters the curvature of spacetime around them. This causes gas, dust, and even photons (light) in their vicinity to fall inwards and form disks that slowly accrete onto their faces, never to be seen again. However, astronomers have also noted that they can produce powerful jets that accelerate charged particles to close to the speed of light (aka. relativistic jets).

These jets lead to powerful gamma-ray bursts (GRBs), which have been observed with black holes that have powerful magnetic fields. However, where these magnetic fields come from has remained a mystery to astrophysicists for some time. According to new research led by scientists from the Flatiron Institute, the source of these fields may have finally been revealed. Based on a series of simulations they conducted that modeled the life cycle of stars from birth to collapse, they found that black holes inherit their magnetic fields from the parent stars themselves.

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Gaze at New Pictures of the Sun from Solar Orbiter

The Solar Orbiter has captured the highest resolution images of the Sun ever during a recent close encounter. The detail is extraordinary. Image Credit: ESA - European Space Agency

74 million kilometres is a huge distance from which to observe something. But 74 million km isn’t such a big deal when the object is the Sun.

That’s how far away from the Sun the ESA/NASA Solar Orbiter was when it captured these new images.

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Are Fast Radio Bursts Caused by Interstellar Objects Crashing Into Neutron Stars?

This magnetar is a highly magnetized neutron star. This artist's illustration shows an outburst from a magnetar. Neutron stars that spin rapidly and give out radiation are called pulsars, and specific pulsars are rare in the core of the Milky Way. Credit: NASA/JPL-CalTech
This magnetar is a highly magnetized neutron star. This artist's illustration shows an outburst from a magnetar. Neutron stars that spin rapidly and give out radiation are called pulsars, and specific pulsars are rare in the core of the Milky Way. Credit: NASA/JPL-CalTech

Every now and then, astronomers will detect an odd kind of radio signal. So powerful it can outshine a galaxy, but lasting only milliseconds. They are known as fast radio bursts (FRBs). When they were first discovered a couple of decades ago, we had no idea what might cause them. We weren’t even sure if they were astronomical in origin. FRB’s were so localized and so short-lived, it was difficult to gather data on them. But with wide-field radio telescopes such as CHIME we can now observe FRBs regularly and have a pretty good idea of their source: magnetars.

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Here’s How to Weigh Gigantic Filaments of Dark Matter

Artist concept of how a galaxy might accrete mass from rapid, narrow streams of cold gas. These filaments provide the galaxy with continuous flows of raw material to feed its star-forming at a rather leisurely pace. Credit: ESA–AOES Medialab

How do you weigh one of the largest objects in the entire universe? Very carefully, according to new research.

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How Could Astronauts Call for Help from the Moon?

Exploring the Moon poses significant risks, with its extreme environment and hazardous terrain presenting numerous challenges. In the event of a major accident, assistance might take days or even weeks to arrive. To address this, Australian researchers have created a distress alert system based upon the COSPAS-SARSAT technology used for Earth-based search and rescue operations. It relies on low-power emergency beacons that astronauts could activate with minimal setup and use a planned lunar satellite network for communication and rescue coordination.

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