Recent Comments

    Earth’s Magnetic field tagged posts

    Surprising discovery shows a strong link between Earth’s magnetic field and atmospheric oxygen levels

    June 20, 2025, Categories  Astronomy/Space

    Every breath we take in contains 21% oxygen, the gas that makes life on Earth possible. Oxygen, in its combined oxide state, has always been abundant in Earth’s crust, but elemental diatomic oxygen became part of our atmosphere around 2.4 to 2.5 billion years ago as a gift from cyanobacteria, which triggered the Great Oxidation Event and breathed life into Earth.

    A joint venture between NASA Goddard Space Flight Center and the University of Leeds discovered that the Earth’s magnetic field strength and atmospheric oxygen levels over the past 540 years have seemed to spike and dip at the same time, showing a strong, statistically significant correlation between the two.

    This correlation could arise from unexpected connections between geophysical processes in Earth’s deep interior,...

    Read More

    Mapping the Milky Way’s Magnetic Field in 3D

    April 29, 2024, Categories  Astronomy/Space, Physics

    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 polarized 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.

    ...Read More

    Researchers track slowly splitting ‘Dent’ in Earth’s Magnetic Field

    August 19, 2020, Categories  Astronomy/Space, Environment/Geology

    Earth’s magnetic field acts like a protective shield around the planet, repelling and trapping charged particles from the Sun. But over South America and the southern Atlantic Ocean, an unusually weak spot in the field – called the South Atlantic Anomaly, or SAA – allows these particles to dip closer to the surface than normal. Currently, the SAA creates no visible impacts on daily life on the surface. However, recent observations and forecasts show that the region is expanding westward and continuing to weaken in intensity. The South Atlantic Anomaly is also of interest to NASA’s Earth scientists who monitor the changes in magnetic strength there, both for how such changes affect Earth’s atmosphere and as an indicator of what’s happening to Earth’s magnetic fields, deep inside the globe...
    Read More

    Magma Ocean may be Responsible for the Moon’s early Magnetic Field

    April 27, 2018, Categories  Astronomy/Space

    The bottom-most layer of the moon's mantle melts to form a metal-rich "basal magma ocean" that sits on top of the moon's metal core. Convection in this layer may have driven a dynamo, creating a magnetic field which would have been recorded at the surface by the cooling lunar crust, including the samples brought back by Apollo astronauts. Credit: Aaron Scheinberg

    The bottom-most layer of the moon’s mantle melts to form a metal-rich “basal magma ocean” that sits on top of the moon’s metal core. Convection in this layer may have driven a dynamo, creating a magnetic field which would have been recorded at the surface by the cooling lunar crust, including the samples brought back by Apollo astronauts. Credit: Aaron Scheinberg

    Around 4 billion years ago, the Moon had a magnetic field that was about as strong as Earth’s magnetic field is today. How the Moon, with a much smaller core than Earth’s, could have had such a strong magnetic field has been an unsolved problem in the history of the Moon’s evolution...

    Read More