The Earth's Magnetosphere Could be Used as a Gravitational Wave Observatory

Gravitational signals might allow astronomers to observe early inflation. Credit: NANOGrav/T. Klein

One of the challenges of gravitational wave astronomy is moving its abilities beyond observations of stellar mass mergers. The collision of two black holes or neutron stars releases a tremendous amount of gravitational energy, but even this is a challenge to detect. Gravitational waves do not couple strongly with most matter, so it takes a tremendous amount of sensitive observations to observe. But we are getting better at it, and there are a few proposals that hope to take our observations even further. One example of this is a recent study that looks at utilizing the magnetospheres of Earth and Jupiter.

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One in Ten Stars Ate a Jupiter (Or Bigger)

This illustration shows a Jupiter-mass exoplanet getting perilously close to its star. Eventually, the star will engulf the planet, something that happens in many stars' lives as they leave the main sequence. Image Credit: C. Carreau / ESA.

In space, cataclysmic events happen to stars all the time. Some explode as supernovae, some get torn apart by black holes, and some suffer other fates. But when it comes to planets, stars turn the tables. Then it’s the stars who get to inflict destruction.

Expanding red giant stars consume and destroy planets that get too close, and a new study takes a deeper look at the process of stellar engulfment.

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Juice Looks Back at Earth During Its Space Odyssey to Jupiter’s Moons

Juice view of Earth
The Horn of Africa and the Gulf of Aden are prominent in this Earth snapshot from the JMC1 camera on the European Space Agency's Juice probe, captured a half-hour after launch on April 14. Credit: ESA / Juice / JMC, CC BY-SA 3.0 IGO

As the European Space Agency’s Juice spacecraft headed out on an eight-year trip to Jupiter’s icy moons, it turned back to snap some selfies with Earth in the background — and those awesome shots are just the start.

The bus-sized probe is due to make four slingshot flybys of Earth and Venus to pick up some gravity-assisted boosts to its destination — and ESA mission managers plan to have the monitoring cameras running during those close encounters.

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ESA's Juice is On Its Way to Visit Jupiter's Moons

ESA’s Juice mission lifted off on an Ariane 5 rocket from Europe’s Spaceport in French Guiana on April 14, 2023 to begin its eight-year journey to Jupiter, where it will study in detail the gas giant planet’s three large ocean-bearing moons: Ganymede, Callisto and Europa. Credits: ESA - S. Corvaja

A new era of exploration at Jupiter’s moons began last week with the launch of the European Space Agency’s Juice, the Jupiter Icy Moons Explorer. This mission will visit three of Jupiter’s largest moons — Europa, Callisto and Ganymede — to investigate whether they could be potentially habitable, a question that’s been highly debated since the first evidence of subsurface oceans on these moons was seen by the Galileo mission in the 1990s.

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It's Time For Your Annual Weather Update for the Outer Solar System

Jupiter, as seen by the Hubble Space Telescope in November 2022 and January 2023. Credits: NASA, ESA, STScI, Amy Simon (NASA-GSFC), and Michael H. Wong (UC Berkeley); Image Processing: Joseph DePasquale (STScI).

A couple times a year, the Hubble Space Telescope turns its powerful gaze on the giant planets in the outer Solar System, studying their cloudtops and weather systems. With the Outer Planet Atmospheres Legacy (OPAL) Program, Hubble provides us with these views and also delivers weather reports on what’s happening. Here’s an updated report and some new images of the stormy surfaces of Jupiter and Uranus.  

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Europa’s Ice Rotates at a Different Speed From its Interior. Now We May Know Why

Image of Europa taken by NASA's Juno spacecraft on Sept 29, 2022. (Credit: NASA/JPL-Caltech/Southwest Research Institute/Malin Space Science Systems)

Jupiter’s moon, Europa, contains a large ocean of salty water beneath its icy shell, some of which makes it to the surface from time to time, and this vast ocean could host life, as well. Europa was most recently observed by NASA’s Juno spacecraft, but current examinations of the moon’s internal ocean are limited to computer models and simulations produced here on Earth, as no mission is actively exploring this tiny moon orbiting Jupiter. Other than the internal water occasionally breaching the icy shell and making it to the surface, what other effects could the internal ocean have on the icy shell that encloses it?

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The Favorite Solar System Moons of Planetary Geologists; An In-Depth Discussion

The Galilean moons of Jupiter: Io, Europa, Ganymede, and Callisto. (Credit: NASA/JPL-Caltech)

The moons of our Solar System have garnered quite a lot of attention in the last few years, especially pertaining to astrobiology and the search for life beyond Earth. From the Galilean moons of Jupiter to the geysers of Enceladus to the methane lakes on Titan, these small worlds continue to humble us with both their awe and mystery. But do the very same scientists who study these mysterious and intriguing worlds have their own favorite moons? As it turns out, seven such planetary geologists were kind enough to share their favorite Solar System moons with Universe Today!

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Just Dropped: New Close-up Images of Io from Juno, With More to Come

Jupiter's Moon Io, as seen by the Juno spacecraft on Perijove 49 on March 1, 2023, from distances between 52,515 to 64,994 km. Credit: NASA/JPL-Caltech/SwRI/MSSS, processed by Andrea Luck.

On March 1, 2023, NASA’s Juno spacecraft flew by Jupiter’s moon Io, coming within 51,500 km (32,030 miles) of the innermost and third-largest of the four Galilean moons. The stunning new images provide the best and closest view of the most volcanic moon in our Solar System since the New Horizons mission flew past Io and the Jupiter system in 2006 on its way to Pluto.

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New Discoveries Puts Jupiter at 92 Known Moons

A top-down overhead view of the orbits of Jupiter's 92 moons. Credit: Scott Sheppard.

The moon hunter strikes again.

A team of astronomers led by Scott Sheppard of the Carnegie Institution has found and confirmed 12 new moons orbiting Jupiter, bringing the total of moons at the giant planet to 92. The new moons were quietly announced on the International Astronomical Union’s Minor Planet Center website last week, and the new discoveries puts Jupiter in the lead in a recent back-and-forth moon battle with Saturn.

Jupiter was solidly in the lead with Sheppard and team’s announcement of 12 new moons back in 2018, but then in 2019, Sheppard and colleagues found a whopping 20 new moons orbiting Saturn, bringing the ringed planet’s total number of moons to 82. But now this latest addition moves Jupiter back in the lead.

With Sheppard around, we may never know the final count.

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Mars Express Watched Deimos Pass in Front of Jupiter and its Moons

Deimos
Deimos, as seen by Mars Express. Credit: ESA.

That’s no moon … wait … yes, it is, and more!

ESA’s Mars Express has captured an unusual and rare occultation, all from its vantage point in orbit of Mars.  The spacecraft’s orbit brought it to the right place where it could witness the moment Mars’ small moon Deimos passed in front of Jupiter and its four largest moons. Scientists say that celestial alignments like these enable a more precise determination of the Martian moons’ orbits.

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