Earth Had a Magnetosphere 3.7 Billion Years Ago

The magnetic field and electric currents in and around Earth generate complex forces that have immeasurable impact on every day life. The field can be thought of as a huge bubble -- called the magnetosphere --, protecting us from cosmic radiation and charged particles that bombard Earth in solar winds. Credit: ESA/ATG medialab
The magnetic field and electric currents in and around Earth generate complex forces that have immeasurable impact on every day life. The field can be thought of as a huge bubble -- called the magnetosphere -- protecting us from cosmic radiation and charged particles that bombard Earth in solar winds. Credit: ESA/ATG medialab

We go about our daily lives sheltered under an invisible magnetic field generated deep inside Earth. It forms the magnetosphere, a region dominated by the magnetic field. Without that planetary protection shield, we’d experience harmful cosmic radiation and charged particles from the Sun.

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Neutron Stars Could be Capturing Primordial Black Holes

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

The Milky Way has a missing pulsar problem in its core. Astronomers have tried to explain this for years. One of the more interesting ideas comes from a team of astronomers in Europe and invokes dark matter, neutron stars, and primordial black holes (PBHs).

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Artemis Astronauts Will Deploy New Seismometers on the Moon

Giordano Bruno crater on the Moon, as seen by the Lunar Reconnaissance Orbiter. This young crater sports impact rays that may help scientists as they consider landing sties for future Artemis missions. Courtesy: NASA/LRO.
Giordano Bruno crater on the Moon, as seen by the Lunar Reconnaissance Orbiter. This young crater sports impact rays that may help scientists as they consider landing sties for future Artemis missions. Courtesy: NASA/LRO.

Back in the 1960s and 1970s, Apollo astronauts set up a collection of lunar seismometers to detect possible Moon quakes. These instruments monitored lunar activity for eight years and gave planetary scientists an indirect glimpse into the Moon’s interior. Now, researchers are developing new methods for lunar quake detection techniques and technologies. If all goes well, the Artemis astronauts will deploy them when they return to the Moon.

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More Views of the 2024 Eclipse, from the Moon and Earth Orbit

NASA's LROC view of the total solar eclipse shadow centered over Cape Girardeau, Missouri. Courtesy: NASA/GSFC/Arizona State University.
NASA's LROC view of the total solar eclipse shadow centered over Cape Girardeau, Missouri. Courtesy: NASA/GSFC/Arizona State University.

It’s been just over a week since millions of people flocked to places across North America for a glimpse of moonshadow. The total solar eclipse of April 8th, 2024 was a spectacular sight for many on the ground. From space, however, it was even more impressive as Earth-observing satellites such as GOES-16 captured the sight of the shadow sweeping over Earth.

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Webb Watches the Most Distant Galactic Merger Ever Seen

JWST shows details of massive galaxy merger 13 billion years ago. Credit: ASTRO 3D
JWST shows details of massive galaxy merger 13 billion years ago. Credit: ASTRO 3D

Astronomers know that galaxies form through mergers. They’ve been happening since the earliest epochs of cosmic time. Using the Webb telescope (JWST) astronomers found a massive merger of young galaxies going on about a half million years after the Big Bang. It’s called Gz9p3, one of the earliest and most distant mergers ever witnessed.

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What Can Europa’s Surface Tell Us About the Thickness of Its Ice?

Jupiter's second Galilean moon, Europa. Its smooth surface has fewer craters than other moons, but they help us understand its icy shell. (Credit: NASA/JPL/Galileo spacecraft)
The Hubble spotted evidence of geysers coming from Jupiter's moon Europa, but nobody's been able to find them again. (Credit: NASA/JPL/Galileo spacecraft)

You can tell a lot about a planetary body just by looking at its surface, especially if it has craters. Take Europa, for example. It has a fairly young surface—somewhere between 50 and 100 million years old. That’s practically “new” when you compare it to the age of the Solar System. And, Europa’s icy crust is pretty darned smooth, with only a few craters to change the topography.

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Finally, an Explanation for the “String of Pearls” in Supernova 1987A

A JWST NIRCam view of Supernova 1987a showing its string of pearls. The keyhole-shaped material at the heart is ejecta from the explosion. NASA, ESA, CSA, Mikako Matsuura (Cardiff University), Richard Arendt (NASA-GSFC, UMBC), Claes Fransson (Stockholm University), Josefin Larsson (KTH)
A JWST NIRCam view of Supernova 1987a showing its string of pearls. The keyhole-shaped material at the heart is ejecta from the explosion. NASA, ESA, CSA, Mikako Matsuura (Cardiff University), Richard Arendt (NASA-GSFC, UMBC), Claes Fransson (Stockholm University), Josefin Larsson (KTH)

Not long after the explosion of Supernova 1987a, astronomers were abuzz with predictions about how it might look in a few years. They suggested a pulsar would show up soon and many said that the expanding gas cloud would encounter earlier material ejected from the star. The collision would light up the region around the event and sparkle like diamonds.

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Webb Reveals Secrets of Neptune’s Evolution

JWST's view of Neptune in infrared. The telescope also studied the surfaces of two icy asteroids in the Kuiper Belt that lie beyond Neptune. Courtesy: NASA, ESA, CSA, STScI
JWST's view of Neptune in infrared. The telescope also studied the surfaces of two icy asteroids in the Kuiper Belt that lie beyond Neptune. Courtesy: NASA, ESA, CSA, STScI

A twinset of icy asteroids called Mors-Somnus is giving planetary scientists some clues about the origin and evolution of objects in the Kuiper Belt. JWST studied them during its first cycle of observations and revealed details about their surfaces, which gives hints at their origins. That information may also end up explaining how Neptune got to be the way it is today.

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The Maximum Mass of a Neutron Star is 2.25 Solar Masses

An outbursting, magnetically strong neutron star called a magnetar is seen here in an artist's illustration. Courtesy: NASA.
An outbursting, magnetically strong neutron star called a magnetar is seen here in an artist's illustration. Courtesy: NASA.

When stars grow old and die, their mass determines their ultimate fate. Many supermassive stars have futures as neutron stars. But, the question is, how massive can their neutron stars get? That’s one that Professor Fan Yizhong and his team at Purple Mountain Observatory in China set out to answer.

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