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On November 14, 2003, astronomers spotted what was at the time the most distant known object orbiting the Sun. They called it Sedna after the Inuit goddess of the ocean. It’s a cold, reddish dwarf planet that drifts billions of miles away from the Sun during its 10,000-year orbit before coming in for a relatively close approach to our star. Its next perihelion is happening in July 2076, and astronomers want to take advantage of this rare encounter by flying a mission to the mysterious object.

A team of researchers from Italy suggests mission concepts that could reach Sedna in seven to 10 years using cutting-edge technology. In a paper available on the pre-print website arXiv, they illustrate two experimental propulsion concepts that involve a nuclear fusion rocket engine and a new take on solar sailing technology. The propulsion technologies could cut down travel time to Sedna by more than 50% compared to traditional methods of space travel, allowing scientists a unique opportunity to gather clues about the early formation of the solar system and probe the theoretical Oort Cloud.

When it was discovered, Sedna was around 8 billion miles (13 billion kilometers) from the Sun. (Pluto, the most famous dwarf planet, has an average distance of 3.7 billion miles from the Sun.) Sedna is known as a Trans-Neptunian object, a group of objects that orbit the Sun farther out than Neptune. It has an extremely eccentric orbit: at its farthest distance, Sedna is 84 billion miles away from the Sun, or 900 times the distance between Earth and our star. During its closest approach, Sedna will be around 7 billion miles away from the Sun, nearly three times farther than Neptune. That’s still far, but it’s close enough for a spacecraft to reach the celestial object before it fades back into ultra-distant darkness.

Spacecraft have traveled farther distances before. Voyager 1 and 2 started their interstellar journey in 1977 and have traveled 15 billion miles and 12.7 billion miles thus far. It took Voyager 2 around 12 years to reach Neptune. Based on current technology, scientists estimate it would take around 20-30 years to reach Sedna during its closest approach, while using Venus, Earth, Jupiter, and Neptune as gravity assists. That would mean the launch window to reach Sedna is fast approaching, with no clear plans yet in place.

Instead, the researchers behind the new study suggest alternative methods to get us there faster. The first is the Direct Fusion Drive (DFD) rocket engine, which is currently under development at Princeton University’s Plasma Physics Laboratory. The fusion-powered rocket engine would produce both thrust and electrical power from a controlled nuclear fusion reaction, providing more power than chemical rockets.

“The DFD presents a promising alternative to conventional propulsion, offering high thrust-to-weight ratio and continuous acceleration,” the researchers write in the paper. “However, its feasibility remains subject to key engineering challenges, including plasma stability, heat dissipation, and operational longevity under deep-space radiation.” They add that, while advances are being made for fusion-based propulsion, it’s still unclear whether it can support long-duration missions and provide power for onboard instruments.

The second concept builds on existing solar sail technology, which is still experimental in its own right. Solar sails are powered by photons from the Sun, harnessing energy produced by light and using it to propel spacecraft forward. The researchers suggest coating the solar sails with material that, when heated, releases molecules or atoms and provides propulsion in a process known as thermal desorption.

The solar sail, assisted by Jupiter’s gravity, could reach Sedna in seven years due to its ability to continuously accelerate without the need to carry heavy fuel, according to the paper. The idea does come with its own set of challenges. “While solar sailing has been extensively studied for deep-space applications, its feasibility for a Sedna mission requires assessment in terms of long-duration structural integrity, propulsion efficiency, and power availability for science operations,” the paper reads.

Despite a slight time advantage, the solar sail mission would only allow for a flyby of Sedna, while the DFD engine could insert a spacecraft into the dwarf planet’s orbit for a longer mission. Either mission would provide us with the first direct observations of the previously unexplored region and help scientists better understand the larger boundary that houses the solar system.

It only took Ed Albin a few steps on June 29 to spot it as he wandered onto an empty construction site about 45 minutes southeast of Atlanta, in the US state of Georgia.

“Oh my God,” he said, crouching down to take a look at his find. “Oh my God.”

Perched on the dirt, like it just fell from the sky, was not just any old rock. It was a chunk of the Georgia fireball that had blazed across the sky on June 26 and disintegrated 43km (27 miles) above West Forest, in Covington, on its way southeast.

In a floppy sun hat and pink shirt, Albin tested the meteorite with a rare earth magnet attached to a metal pole. It gave a faint hint of magnetic attraction, its nickel iron flecks pulling it toward the magnet – proof of its descent from outer space.

Another hunter, Sonny Clary, ran over to take a look.

“Millions of years flying in outer space,” he said in awe. “How cool is that?”

An unexpectedly strong solar storm rocked our planet on April 23, 2023, sparking auroras as far south as southern Texas in the U.S. and taking the world by surprise.

Two days earlier, the Sun blasted a coronal mass ejection (CME) – a cloud of energetic particles, magnetic fields, and solar material – toward Earth. Space scientists took notice, expecting it could cause disruptions to Earth’s magnetic field, known as a geomagnetic storm. But the CME wasn’t especially fast or massive, and it was preceded by a relatively weak solar flare, suggesting the storm would be minor. But it became severe.

Using NASA heliophysics missions, new studies of this storm and others are helping scientists learn why some CMEs have more intense effects – and better predict the impacts of future solar eruptions on our lives.

Why Was This Storm So Intense?

A paper published in the Astrophysical Journal on March 31 suggests the CME’s orientation relative to Earth likely caused the April 2023 storm to become surprisingly strong.

The researchers gathered observations from five heliophysics spacecraft across the inner solar system to study the CME in detail as it emerged from the Sun and traveled to Earth.

They noticed a large coronal hole near the CME’s birthplace. Coronal holes are areas where the solar wind – a stream of particles flowing from the Sun – floods outward at higher than normal speeds.

“The fast solar wind coming from this coronal hole acted like an air current, nudging the CME away from its original straight-line path and pushing it closer to Earth’s orbital plane,” said the paper’s lead author, Evangelos Paouris of the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland. “In addition to this deflection, the CME also rotated slightly.”

Paouris says this turned the CME’s magnetic fields opposite to Earth’s magnetic field and held them there – allowing more of the Sun’s energy to pour into Earth’s environment and intensifying the storm.

Cool Thermosphere

Meanwhile, NASA’s GOLD (Global-scale Observations of Limb and Disk) mission revealed another unexpected consequence of the April 2023 storm at Earth.

Before, during, and after the storm, GOLD studied the temperature in the middle thermosphere, a part of Earth’s upper atmosphere about 85 to 120 miles overhead. During the storm, temperatures increased throughout GOLD’s wide field of view over the Americas. But surprisingly, after the storm, temperatures dropped about 90 to 198 degrees Fahrenheit lower than they were before the storm (from about 980 to 1,070 degrees Fahrenheit before the storm to 870 to 980 degrees Fahrenheit afterward).

“Our measurement is the first to show widespread cooling in the middle thermosphere after a strong storm,” said Xuguang Cai of the University of Colorado, Boulder, lead author of a paper about GOLD’s observations published in the journal JGR Space Physics on April 15, 2025.

The thermosphere’s temperature is important, because it affects how much drag Earth-orbiting satellites and space debris experience.

“When the thermosphere cools, it contracts and becomes less dense at satellite altitudes, reducing drag,” Cai said. “This can cause satellites and space debris to stay in orbit longer than expected, increasing the risk of collisions. Understanding how geomagnetic storms and solar activity affect Earth’s upper atmosphere helps protect technologies we all rely on – like GPS, satellites, and radio communications.”

Predicting When Storms Strike

To predict when a CME will trigger a geomagnetic storm, or be “geoeffective,” some scientists are combining observations with machine learning. A paper published last November in the journal Solar Physics describes one such approach called GeoCME.

Machine learning is a type of artificial intelligence in which a computer algorithm learns from data to identify patterns, then uses those patterns to make decisions or predictions.

Scientists trained GeoCME by giving it images from the NASA/ESA (European Space Agency) SOHO (Solar and Heliospheric Observatory) spacecraft of different CMEs that reached Earth along with SOHO images of the Sun before, during, and after each CME. They then told the model whether each CME produced a geomagnetic storm.

Then, when it was given images from three different science instruments on SOHO, the model’s predictions were highly accurate. Out of 21 geoeffective CMEs, the model correctly predicted all 21 of them; of 7 non-geoeffective ones, it correctly predicted 5 of them.

“The algorithm shows promise,” said heliophysicist Jack Ireland of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who was not involved in the study. “Understanding if a CME will be geoeffective or not can help us protect infrastructure in space and technological systems on Earth. This paper shows machine learning approaches to predicting geoeffective CMEs are feasible.”

Earlier Warnings

During a severe geomagnetic storm in May 2024 – the strongest to rattle Earth in over 20 years – NASA’s STEREO (Solar Terrestrial Relations Observatory) measured the magnetic field structure of CMEs as they passed by.

When a CME headed for Earth hits a spacecraft first, that spacecraft can often measure the CME and its magnetic field directly, helping scientists determine how strong the geomagnetic storm will be at Earth. Typically, the first spacecraft to get hit are one million miles from Earth toward the Sun at a place called Lagrange Point 1 (L1), giving us only 10 to 60 minutes advanced warning.

By chance, during the May 2024 storm, when several CMEs erupted from the Sun and merged on their way to Earth, NASA’s STEREO-A spacecraft happened to be between us and the Sun, about 4 million miles closer to the Sun than L1.

A paper published March 17, 2025, in the journal Space Weather reports that if STEREO-A had served as a CME sentinel, it could have provided an accurate prediction of the resulting storm’s strength 2 hours and 34 minutes earlier than a spacecraft could at L1.

According to the paper’s lead author, Eva Weiler of the Austrian Space Weather Office in Graz, “No other Earth-directed superstorm has ever been observed by a spacecraft positioned closer to the Sun than L1.”