The 10 Most Significant Space Events of 2024

The year 2024 has been packed with remarkable achievements in the field of space exploration. Successful launches by SpaceX’s Super Heavy and ESA’s Ariane 6, important scientific missions and discoveries, the first space tourists venturing into open space, and the final decision on the fate of the International Space Station (ISS) all took place this year. Let’s look back and examine the key milestones of the past 12 months.  

New scientific missions: Europa Clipper, PACE, and PROBA-3  

2024 marked the launch of several scientific missions aimed at significantly expanding humanity’s knowledge of planets, ecosystems, and cosmic phenomena.  

On February 8, 2024, NASA launched a climate mission aboard a SpaceX Falcon 9 rocket from Cape Canaveral, Florida. The mission’s purpose is to study the ocean and atmosphere. The Plankton, Aerosol, Cloud, & ocean Ecosystem (PACE)  satellite is designed to investigate microorganisms and microparticles in the ocean, offering insights into our planet. According to NASA, PACE will help us better understand how atmospheric and oceanic particles impact Earth’s climate, particularly vis-a-vis global warming. For the first time, scientists will be able to monitor air quality, track the distribution of phytoplankton in marine environments, and study how sunlight interacts with particles in the atmosphere directly from space. Ultimately, this mission will provide a clearer understanding of the ocean-atmosphere relationship and their combined influence on global climate.  

The spacecraft and all research equipment for the PACE mission were developed at NASA’s Goddard Space Flight Center.  

On October 14, 2024, the Europa Clipper probe was launched. As the name suggests, its purpose is to study Europa, one of Jupiter’s Galilean moons (also known as the Galilean satellites). The probe is set to become the largest spacecraft ever developed by NASA for a planetary mission. After traveling 2.9 billion kilometers, it is expected to arrive at Jupiter in 2030 to begin collecting data.  

Then, in 2031, Europa Clipper will initiate a series of flybys, during which time specialized instruments will be used to confirm or refute the theory that Europa’s icy surface and subsurface ocean could harbor conditions suitable for life. Previously, the Galileo spacecraft, which orbited Jupiter from 1995 to 2003, detected evidence suggesting that components essential for life might exist on Europa.  

On December 5, 2024, one of the most ambitious European solar research missions, PROBA-3, was launched from the Satish Dhawan Space Centre on Sriharikota Island, India. The mission consists of two spacecraft launched synchronously: the CSC (Coronagraph Spacecraft) and the OSC (Occulter Spacecraft). These spacecraft will align with the Sun at a distance of 150 meters from each other, with one casting a controlled shadow on the other.  

The goal of PROBA-3 is to create an artificial “solar eclipse,” which will enable scientists to study the Sun’s corona. This will help address questions such as why the corona is significantly hotter than the Sun’s surface, how the solar wind accelerates, the mechanisms of coronal mass ejections, and the behavior of electrons trapped in Earth’s radiation belts.  

The significance of PROBA-3 also extends beyond its primary mission. Its success will demonstrate the feasibility of precise coordination between two separate spacecraft maintaining a fixed distance from one another. This breakthrough makes it likely that, in the future, other research could be conducted simultaneously from multiple platforms working together as a single unit.

Three discoveries: evolving dark matter, “empty” galaxies, and ancient dwarf galaxies 

2024 saw three major astronomical discoveries, each of which significantly advanced the fields of exoplanet research, cosmology, and astrophysics.  

In January 2024, scientists identified two “empty,” or starless, galaxies that are so diffuse that they never actually formed stars. This discovery challenges the very definition of a “galaxy,” which is traditionally understood as a gravitationally bound system of stars, star clusters, interstellar gas and dust, planets, and dark matter.  

One of these “empty” galaxies, named Nube, or “cloud,” is located 300 million light-years from Earth. These galaxies contain the gas necessary for star formation, yet no stars have formed, leaving scientists with the puzzle of understanding why.

In April 2024, it was discovered that dark matter may actually evolve over time, challenging the previous belief that it has remained constant throughout the Universe’s existence. This hypothesis was proposed by astronomers who created the largest-ever three-dimensional map of dark matter. If future data confirm their theory, it could be as revolutionary as the discovery of the accelerated expansion of the Universe itself.

The third important discovery of 2024 was made using the James Webb Space Telescope (JWST). Thanks to its exceptional infrared capabilities, the telescope is able to capture unique images of the most distant galaxies, including those emitting extremely faint light.  

At the beginning of the year, astronomers using the JWST discovered so-called “dwarf” galaxies that formed shortly after the birth of the Universe and illuminated it during its first few hundred million years of existence.  

The European Space Agency launches Ariane 6

This year, ESA successfully launched its heavy-lift launch vehicle, Ariane 6, with its maiden flight taking place on July 9, 2024, from the European Spaceport in French Guiana. Although the mission was primarily demonstrative, several payloads were onboard.  

Unlike its predecessor, Ariane 5, the new Ariane 6 in its Ariane 62 configuration features an improved modular design, enabling missions to low Earth orbit (LEO). With a mass of 540 tons, it can deliver up to 10.3 tons of cargo to LEO and up to 4.5 tons to a geostationary transfer orbit (GTO).

The Ariane 6 launch demonstrated the rocket’s ability to successfully deliver payloads into space. More importantly, it marked a significant step toward overcoming Europe’s “space crisis.” With the Russian Soyuz program abandoned, the Vega C launch failure, and delays in the development of Ariane 6, Europe was left with virtually no backup options.  

Against the backdrop of SpaceX’s dominance in reusable rockets, the situation appeared to be quite grim. The success of Ariane 6 helped mitigate this issue, giving Europe the capability to independently conduct space launches. However, ESA still cannot compete with Elon Musk’s company in terms of launch costs, neither with the medium-lift Ariane 62 nor the heavy-lift Ariane 64 configuration.

First successful launch and landing of Super Heavy

After less-than-successful Starship/Super Heavy launches in 2023, SpaceX finally achieved its goal. On June 6, 2024, during the fourth test flight, the booster made a soft landing in the Gulf of Mexico. Four months later, on October 13, Super Heavy returned to the launch pad, where it was captured and secured by the “Mechazilla” tower’s manipulators. During this operation, the 250-ton booster sustained less visible damage as compared to previous launches. The Starship spacecraft itself was placed on its calculated trajectory and successfully splashed down in the Indian Ocean.

SpaceX has demonstrated that it can learn quickly from its mistakes and proved that it is possible to return a booster to the launch site. Super Heavy was primarily designed for the cost-effective delivery of cargo to space: initially up to 100 tons, with the potential to increase to 150 tons. It is expected that Starship will be refuelable in orbit and can be effectively used for satellite launches to low Earth orbit, resupply missions to the ISS and commercial stations, crewed tourist and scientific missions, and, the hope is, for exploring and colonizing Mars in the future.  

In the long term, Starship will replace other rockets and space transportation solutions from SpaceX, such as Falcon 9, Falcon Heavy, and Dragon 2. This will largely be made possible by the reduction in launch costs, enabling a more economical transportation of people and payloads.

Polaris Dawn and the first space tourists in open space 

The private Polaris space program was organized in 2022 by billionaire entrepreneur and astronaut Jared Isaacman, who had previously commanded the Inspiration4 mission. He also led Polaris Dawn, the first private flight during which commercial space tourists, including Isaacman himself, ventured into open space. The mission, managed by SpaceX, began on September 10, 2024, and was the first of three planned missions under the Polaris program. The expedition aboard the Dragon 2 spacecraft lasted until September 15, 2024. During this time, the spacecraft completed several orbits before ascending to a height of 1,400 km—the highest altitude reached in a crewed flight since the last Apollo mission in 1972.

Along with the billionaire, a former combat pilot and two SpaceX employees with mission experience also ventured into open space. The crew members were the first to wear a new type of spacesuit designed by SpaceX specifically for extravehicular activities using innovative materials. The modified spacesuits included a new thermal regulation system, a new helmet visor coating, and a camera and display integrated into the visor.

Japan successfully launched two rockets into space

Last year, the first two test flights of Japan’s newest rocket, H3, ended in failure. However, in 2024, the Japan Aerospace Exploration Agency (JAXA) made a comeback and successfully launched it twice: first on February 17 and again on November 4. Earlier, in January 2024, the lunar module, SLIM, made a pinpoint landing, making Japan the fifth country in the world to send a spacecraft to the Moon.  

The February launch of the new flagship H3 rocket helped revitalize Japan’s space program, which has not yet successfully positioned itself as a significant player in space while increasing competition with China. During the first two-hour flight, the rocket deployed a microsatellite and a satellite model. During the November flight, the Kirameki 3 (or DSN-3) military communication satellite was launched.

Astronomical events: total solar eclipse and Earth’s “mini-moon”

2024 was marked by several notable astronomical events. For example, on April 8, a total solar eclipse could be observed simultaneously in the United States, Canada, and Mexico for the first time in the 21st century. It was also partially visible in Western Europe. To offer customers an opportunity to witness this rare phenomenon up close, Delta Air Lines organized a special flight from Austin to Detroit aboard an A220-300 aircraft with large windows. The next such opportunity for Americans will only occur in March 2033.  

Moreover, last fall, the Moon temporarily lost its status as Earth’s only natural satellite due to the appearance of asteroid 2024 PT5, which measured approximately 11 meters in diameter. For nearly two months, from late September to late November, it served as Earth’s “mini-moon” before departing into the Solar System and continuing to orbit the Sun. Asteroids like Arjuna periodically pass near Earth, having a similar orbit. This time, one of them came within nearly 3 million kilometers, where it was captured by Earth. The closest approach was recorded on August 8, when the distance between the objects narrowed to 567,000 km. It is estimated that the asteroid will return to Earth’s orbit again in May 2084. As before, it will not pose any threat.  

Last December, large asteroids also approached Earth. One of them, approximately 6 meters in width, passed at a distance of 735,000 km.

The new Boeing Starliner made its first flight, and for the first time, was piloted by a woman

Indian-American astronaut Sunita Williams became the first woman to pilot a brand-new spacecraft during its first test flight. The 58-year-old Williams, serving as spacecraft commander, and Butch Wilmore, the second crew member, launched on June 5, 2024, from Cape Canaveral, Florida, aboard Boeing’s Starliner capsule. Initially, the mission was planned to last eight days, but due to engine issues caused by a helium leak, the astronauts will not be able to return to Earth earlier than February 2025 as part of SpaceX’s Crew-9 mission, a decision made by NASA for safety reasons.

This achievement is not Williams’s first career milestone. In 2006, she set a world record for women by conducting four spacewalks, with a total duration of 29 hours and 17 minutes, and in 2012, she spent 50 hours and 40 minutes in space. Both records were later surpassed by another astronaut, Peggy Whitson.

The Boeing CST-100 Starliner is meant to be a reusable crewed spacecraft, and is already being called the “space capsule of the 21st century.” It was developed to accommodate seven crew members or four crew members and cargo for flights to low Earth orbit—specifically for NASA’s service missions to the ISS. Its unique seamless design allows it to be used up to ten times with a six-month interval between flights. On September 6, 2024, the Starliner returned to Earth after its second test orbital flight. Meanwhile, Sunita Williams and Butch Wilmore continue their work on the ISS as part of Expedition 71/72.

The fate of the ISS

In June 2024, NASA released a report on the decommissioning of the International Space Station (ISS). The agency listed all possible options and highlighted the best one: an intentional deorbit, scheduled to begin in 2030. Alternatives considered included dismantling the station with a staged return to Earth, moving it to a higher orbit, and transferring it to a commercial operator. However, the first two options were deemed technically infeasible and the third was complicated by the fact that ISS components technically belong to multiple countries. The report stated that “the controlled deorbit of the space station at the end of its service life is the safest and only feasible method of decommissioning this historic symbol of science, technology, and cooperation.”

On the day the report was published, details of a $843 million contract between NASA and SpaceX were unveiled. The agency chose SpaceX to develop the United States Deorbit Vehicle (USDV), a spacecraft that will perform the controlled descent of the ISS and help avoid risks to people on Earth. The USDV is expected to carry out a series of maneuvers to move the station to a remote, pre-designated location in the southern Pacific Ocean. 

It is anticipated that the ISS’s outer shell and equipment will burn up due to intense heat during reentry into the atmosphere, while more heat-resistant components will fall into the ocean and settle on its floor. NASA is also exploring the possibility of using some components for commercial and demonstration purposes.

Interstellar’s return to the big screen

Christopher Nolan’s “Interstellar” returned to the big screen in celebration of its 10th anniversary. The screening of one of the greatest science fiction films of all time began in IMAX format on December 6, 2024, at select theaters across the United States. At the time of its release, the film received five Academy Award nominations, winning one for “Best Visual Effects.” However, it is remembered for more than just that: the film accurately captured the atmosphere of a supermassive black hole, with the script being based on the scientific theories of renowned American theoretical physicist and astronomer Kip Thorne.