BepiColombo’s New Images of Mercury are Cool

BepiColombo captured this image of Mercury with its Monitoring Camera 3 when it was about 555 km above the surface. It shows the newly-named Stoddart Crater. Image Credit: ESA/BepiColombo/MTM CC BY-SA 3.0 IGO

The ESA/JAXA BepiColombo spacecraft made another flyby of its eventual target, Mercury. This is one of a series of Mercury flybys, as the spacecraft completes a complex set of maneuvers designed to deliver it to the innermost planet’s orbit. Its cameras captured some fantastic images of Mercury.

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Why is the Sun’s Corona So Hot? One Hypothesis Down, Many to Go

Illustration of NASA’s Parker Solar Probe flying through a magnetic switchback from the Sun, with scientists still debating the origin of switchbacks within the Sun. (Credit: Adriana Manrique Gutierrez/NASA’s Goddard Space Flight Center)

The temperature of the Sun’s corona is a minimum of 100 times hotter than the Sun’s surface, despite the corona being far less dense and extending millions of miles from the Sun’s surface, as well. But why is this? Now, a recent study published in The Astrophysical Journal could eliminate a longstanding hypothesis regarding the processes responsible for the corona’s extreme heat, which could help them better understand the Sun’s internal processes. This study holds the potential to help scientists gain greater insight into the formation and evolution of our Sun, which could lead to better understanding stars throughout the universe, as well.

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Planetary Habitability Depends on its Star’s Magnetic Field

Earth's magnetosphere is the region defined by our planet's magnetic field. Image Credit: NASA
Earth's magnetosphere is the region defined by our planet's magnetic field. Image Credit: NASA

The extrasolar planet census recently passed a major milestone, with 5500 confirmed candidates in 4,243 solar systems. With so many exoplanets available for study, astronomers have learned a great deal about the types of planets that exist in our galaxy and have been rethinking several preconceived notions. These include the notion of “habitability” and whether Earth is the standard by which this should be measured – i.e., could there be “super habitable” exoplanets out there? – and the very concept of the circumsolar habitable zone (CHZ).

Traditionally, astronomers have defined habitable zones based on the type of star and the orbital distance where a planet would be warm enough to maintain liquid water on its surface. But in recent years, other factors have been considered, including the presence of planetary magnetic fields and whether they get enough ultraviolet light. In a recent study, a team from Rice University extended the definition of a CHZ to include a star’s magnetic field. Their findings could have significant implications in the search for life on other planets (aka. astrobiology).

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Solar Flares and Solar Magnetic Reconnection Get New Spotlight in Two Blazing Studies

Image of a solar flare (bright flash) obtained by NASA’s Solar Dynamics Observatory on Oct. 2, 2014, with a burst of solar material erupting being observed just to the right of the solar flare. (Credit: NASA/SDO)

Two recent studies published in The Astrophysical Journal discuss findings regarding solar flare properties and a new classification index and the Sun’s magnetic field, specifically what’s called solar magnetic reconnection. These studies hold the potential to help researchers better understand the internal processes of the Sun, specifically pertaining to solar flare activity and space weather. Here, Universe Today discusses these two studies with both lead authors regarding the motivation behind the studies, significant results, and implications on our understanding regarding solar flares and space weather.

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Measuring Exoplanetary Magnetospheres with the Square Kilometer Array

Earth's magnetosphere

Life on Earth would not be possible without food, water, light, a breathable atmosphere and surprisingly, a magnetic field. Without it, Earth, and its inhabitants would be subjected to the harmful radiation from space making life here, impossible. If we find exoplanets with similar magnetospheres then those worlds may well be habitable. The Square Kilometer Array (SKA) which is still under construction should be able to detect such magnetospheres from radio emissions giving us real insight into our exoplanet cousins. 

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Planetary Geophysics: What is it? What can it teach us about finding life beyond Earth?

Artist's illustration of terrestrial (rocky) planet interiors. (Credit: NASA)

Universe Today has examined the importance of studying impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, and planetary atmospheres, and how these intriguing scientific disciplines can help scientists and the public better understand how we are pursuing life beyond Earth. Here, we will look inward and examine the role that planetary geophysics plays in helping scientists gain greater insight into our solar system and beyond, including the benefits and challenges, finding life beyond Earth, and how upcoming students can pursue studying planetary geophysics. So, what is planetary geophysics and why is it so important to study it?

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An Astronomical First! A Radiation Belt Seen Outside the Solar System

Artist’s impression of an aurora and the surrounding radiation belt of the ultracool dwarf LSR J1835+3259. Credit: Chuck Carter/Melodie Kao/Heising-Simons Foundation)

In 1958, the first satellites launched by the United States (Explorer 1 and 3) detected a massive radiation belt around planet Earth. This confirmed something that many scientists suspected before the Space Age began: that energetic particles emanating from the Sun (solar wind) were captured and held around the planet by Earth’s magnetosphere. This region was named the Van Allen Belt in honor of University of Iowa professor James Van Allen who led the research effort. As robotic missions explored more of the Solar System, scientists discovered similar radiation belts around Jupiter, Saturn, Uranus, and Neptune.

Given the boom in extrasolar planet research, scientists have eagerly awaited the day when a Van Allen Belt would be discovered around an exoplanet. Thanks to a team of astronomers led by the University of California, Santa Cruz (UCSC) and the National Radio Astronomy Observatory (NRAO), that day may have arrived! Using the global High Sensitivity Array (HSA), the team obtained images of persistent, intense radio emissions from an ultracool dwarf star. These revealed the presence of a cloud of high-energy particles forming a massive radiation belt similar to what scientists have observed around Jupiter.

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It's Time for Mysterious Spokes to Appear in Saturn's Rings

The Hubble Space Telescope captured this image of Saturn in February, 2023. Image Credit: STScI

The Hubble Space Telescope recently captured the appearance of several asymmetrical ‘spokes’ rising above the rings of Saturn, marking a coming change in season for the ringed gas giant. The spokes are made of charged ice particles bulging up and away from the rest of the rings. Researchers aren’t sure exactly what causes the spokes, but they suspect it has something to do with the planet’s powerful magnetic fields.

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You’re Looking at a Map of the Milky Way’s Magnetic Field

Colour shows the polarized microwave emission measured by QUIJOTE. The pattern of lines superposed shows the direction of the magnetic field lines. Credit: The QUIJOTE Collaboration.

Using telescopes that study the sky in the microwave part of the electromagnetic spectrum, astronomers have successfully mapped the structure of the magnetic field of the Milky Way galaxy. While magnetic fields are difficult to measure in space, an international team of astronomers used the Teide Observatory on Tenerife in the Canary Islands to conduct 10 years of observations.

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Marsquakes are Caused by Shifting Magma

Mars' interior as revealed by the NASA/DLR InSight lander. Image Credit: Cottar, Koelemeijer, Winterbourne, NASA

Before the InSight Lander arrived on Mars, scientists could only estimate what the planet’s internal structure might be. Its size, mass, and moment of inertia were their main clues. Meteorites, orbiters, and in-situ sampling by rovers provided other clues.

But when InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) arrived on Mars in November 2018 and deployed its seismometer, better data started streaming in.

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