The Israeli startup company Hopper is on the final list of the European Space Agency's technology accelerator, surprising findings about the moon, and especially close black holes. This week in space.

The Israeli start-up company WeSpace is among five companies selected to participate in the ESRIC program, a joint initiative for promoting space-sector start-ups organized by the Luxembourg government and the European Space Agency (ESA). Companies that have reached this stage receive three months of product development mentorship, and at the end of the process, one company will be chosen to receive a financial grant and assistance in establishing its operations in Luxembourg, which in recent years has been increasingly supporting space sector-related enterprises. WeSpace is developing autonomous moon-surface drones that employ rocket propulsion, since other forms of flight are not possible there due to the lack of an atmosphere. 

The development of these aerial vehicles, dubbed "Hoppers", is led by Yigal Harel, former head of the space program at SpaceIL – the Israeli non-profit organization that endeavored to land on the moon in 2019 but crashed during its landing attempt. Harel now serves as the CTO of WeSpace Technologies, alongside his co-founder Yifat Feffer who serves as CEO. "The great advantage of our drones is the navigation, flight, and guidance system, which allows autonomous flight even without direct communication with the Earth or with infrastructure on the moon," Harel told the Davidson Institute website. "This is our main intellectual property, and it's a flexible system that can easily be adapted to different mission trajectories and drones of different sizes."

The company plans to build drones powered by clean fuel, based on oxygen-enriched water. The plan is to produce three sizes of drones – ranging from a few kilograms to hundreds of kilograms. These versatile vehicles will be tasked with mapping the moon's surface, assessing its permeability and accessibility for wheeled vehicles, to identify potential landing sites, and primarily to locate local resources such as specific minerals, and particularly ice. Previous research suggested the presence of significant frozen water reserves around the moon's south pole, in perpetually shadowed regions or beneath the lunar surface. Locating such water could be the key to long-term human activity on the moon: it would be used for drinking and agriculture, and equally important, for the production of oxygen and hydrogen. The oxygen is essential for breathing, but the combination of both gasses also serves as rocket fuel, essential for propelling rockets, spacecraft, and even the drones themselves, which would otherwise be single-use vehicles. "The big advantage of the drones is access to difficult places, including craters that a wheeled vehicle cannot descend to," Feffer said. "And mainly – they are much faster than any rover. If rovers travel a few meters a day, a drone designed for a half an hour of flight can map tens of kilometers in that brief timeframe."

 A flexible and intelligent flight system. Harel, Feffer, and the drone’s blueprint | Photo by Itay Nevo.

The company began its operations within the framework of the aerospace industry's technology accelerator. As they collaborate with the ESRIC accelerator, WeSpace is nearing the conclusion of discussions with a leading U.S. space company. This partnership could provide WeSpace with an entryway to NASA's tenders. According to Feffer and Harel, NASA has already expressed informal interest in the project. "NASA is interested in launching our drone, equipped with a range of spectrometers for mapping areas near the lunar south pole for the upcoming Artemis program," says Harel.

"Our drone can pave the way for infrastructure establishment on the moon and assist in transitioning from the operations of large entities, such as space agencies, to the operations of private companies," emphasizes Feffer. "Once water is discovered there, it will be possible to produce hydrogen and oxygen and fuel it, and the potential for this is huge. Alongside our work with NASA, participation in the accelerator, led by the European Space Agency, also opens doors to European markets and we are optimistic that more companies will recognize the innovation in our product and join, including Israel-based companies.

Mapping tens of kilometers in just half an hour of flight, even in terrain that is otherwise inaccessible. The drone of the Israeli start-up company | Visualization: WeSpace.

Hard to Find Ice 

Another interesting finding pertains to the concentration of electric charges above the moon's surface. While the moon lacks a true atmosphere, it does have a very thin plasma layer composed of electrons and ions (electrically charged atoms). Measurements of this plasma showed an electron concentration ranging from 50 million to 300 million electrons per cubic meter, significantly lower than Earth's ionosphere, which has approximately a million electrons per cubic centimeter, and is located tens of kilometers above the ground. According to the researchers, this discovery eases concerns about communication and navigation challenges during future missions to this region, concerns that would have arisen had the plasma been denser.

The spacecraft's instruments also detected an unexpected abundance of sulfur within the moon's soil. It is still unclear whether it originates from ancient volcanic activity on the lunar surface or from asteroid impacts at later stages. Notably, the lander’s seismograph also detected one anomalous movement, and researchers are trying to determine whether it was a minor lunar quake or a meteorite impacting the lunar surface. The new findings underscore the profound gaps in our understanding of our nearest celestial neighbor, despite numerous lunar missions, including manned ventures. The southern polar region in particular, remains unexplored on the lunar surface and warrants further exploration.  Enhanced understanding of this region is particularly important as we contemplate sending humans back to the moon, especially for extended missions.

 We still have a lot to learn about the moon, particularly about its southern polar region. The Indian lander Vikram captured by the rover Pragyan | Source: ISRO.

Seeing Darkness Nearby - Hidden Black Holes in Our Cosmic Proximity?  

In the center of our galaxy, the Milky Way, situated approximately 27,000 light years away from Earth, resides a colossal black hole known as Sagittarius A*. Now, a team of astronomers reports the possible presence of a black hole much closer to us, only about 150 light years away, and possibly even more than one. The team, led by Stefano Torniamenti from the University of Padua in Italy, conducted extensive computer simulations of celestial body movements within the Hyades, an open star cluster within the Taurus constellation. Open clusters are loosely structured regions, abundant with stars that were born from the same gas cloud, thus sharing a similar age and composition. The research team conducted a set of simulations of star formation in this cluster, spanning several light years. In some of these simulations, the potential presence of black holes was introduced. Subsequently, the simulation results were compared with data collected by the European Space Telescope Gaia, which maps the Milky Way.

"Our simulations can only simultaneously match the mass and size of the Hyades if some black holes are present at the center of the cluster today (or until recently),"  said Torniamenti. Impressively, simulations resembling the cluster's present state most closely, featured the existence of two or three black holes in the cluster, although it's possible they may no longer be there. Even if these black holes were present in the cluster and subsequently ejected from it within the last 150 million years, the simulations still remarkably mirror the current scenario. Even in this scenario, the black holes are likely still positioned in the vicinity of the cluster, potentially making them the nearest black holes to our solar system - significantly closer than the nearest known black hole, which is situated approximately 1,500 light years away.

Can you spot the black hole hiding in the photograph? Or perhaps two or three of them? For now, even the scientists don't have the answer. The Hyades Cluster | Photo: Jose Mtanous