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The Orbital Index

Issue No. 327 | Jul 16, 2025


🚀 🌍 🛰
 

ESA selects 5 from the field of Euro launch startups. Moving forward with the European Launcher Challenge (ELC), first announced in 2023, Europe’s space agency ‘preselected’ five proposals for either launch contracts for ESA missions or for demonstrating improved launch services. These five will now compete for phase two selection with launch contracts available as soon as 2026. However, the agency is looking to its member countries to fund these selected companies, meaning each selected startup may encounter a very different funding environment. The startups downselected to submit proposals for the next phase of the process are:

  • Isar Aerospace (Germany). Isar, the first of two German launch startups in the group, is the only company of the five to have ever attempted an orbital launch. In March, their first rocket failed seconds after liftoff from its Norwegian launch pad. Isar is developing Spectrum, capable of launching 1,000 kg of payload to LEO.
  • PLD Space (Spain). PLD has launched their Miura 1 suborbital rocket once, completing a reasonably successful low altitude first mission— intended recovery of the booster was unsuccessful, sinking before it could be retrieved. They are working on the scaled-up, liquid-fueled Miura 5, possibly launching sometime next year and capable of ~1,100 kg to LEO.
  • Orbex (UK). Orbex is developing its Prime propane-fueled micro-launch system (200 kg payload to LEO) with a first demonstration currently planned for 2026 from SaxaVord. Orbex originally started as a failed crowdfunding effort to send a private spacecraft to the Moon.
  • Rocket Factory Augsburg (Germany). Germany’s second preselected startup may have to compete with Isar for domestic funding. RFA, also launching from SaxaVord, had a static fire anomaly in 2024, resulting in the loss of their first rocket and damage to their ground systems. RFA One is designed to lift 1,600 kg to LEO.
  • MaiaSpace (France). A subsidiary of ArianeGroup, so perhaps unfairly labeled a startup, the company is developing a launch vehicle focused on reusability and next-generation launch capabilities, relying on ESA’s Prometheus engine project for its reusable first stage. It plans to launch its Maia vehicle on an inaugural flight in 2026 with a LEO payload capability of 1,500 kg (expandable to 2,500 kg when fully expendable and with the addition of a future third-stage kick stage).
  • This doesn’t represent all the vehicles that might launch from Europe in the near future, however. Passed over in the selection were Skyrora (UK) and Latitude (France), potentially along with HyImpulse, HyPrSpace, DARK, Pangea, and The Exploration Company (the 12 ELC proposals were not publicly released).

The five launchers selected for phase two of the ELC (Left to Right: RFA One, Isar Spectrum, Orbex Prime, PLD Miura 5, MaiaSpace Maia). Credit: European Spaceflight

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Weird papers (about the Moon).

  • While near-Earth asteroid 2024 YR4 won’t hit Earth, there’s currently an estimated 4.3% probability that it will hit the Moon in 2032. A recent, not yet-peer-reviewed paper estimates that 100 million kilograms of material could be ejected, 10% of which could enter Earth’s atmosphere if the object hits the lunar near side. Little would reach the ground, but humanity’s spacecraft in orbit would be at risk.
  • A mathematical model of how our Universe could be the result of a black hole in a parent universe collapsing and then bouncing in a way that looks like inflation. This model makes testable predictions about how space-time should curve if this is true (paper), something future experiments can check on. Broadly, this type of model is a form of Black hole cosmology.
  • European company Lunar Cargo proposes a net-like structure on the Moon which could catch and decelerate cargo from lunar orbit, like a giant catcher’s mitt. With the tortured acronym of MACEDONAS, the Momentum Absorption Catcher for Express Deliveries on Non-Atmospheric Somata system would allow delivery of cargo to the Moon without retropropulsion or high-speed ejecta debris. (Okay, we can’t find a paper, but this kind of had to go in this particular newsletter section.)
  • Railguns or coilguns on the Moon could be a means to deliver mined lunar material to orbit for utilization. However, the lunar gravity field is uneven, and uncontrolled objects tend to impact the surface after a low number of orbits. A recent paper looks at using existing lunar gravity anomalies, aligned with specific launch sites and directions, to find orbits where a passive projectile could remain in orbit much longer before crashing back into the surface (at about 1.7 km/s). They found some orbits that could remain stable for up to 9 Earth days, sufficient time for space vehicles to rendezvous with launched material and collect it for refueling / manufacturing / blocking out the sun.

Astronomers are a little unsure of the applicability of this index, but NASA's Planetary Protection Officer is all in favor.XKCD #2908

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News in brief. ESA and NASA successfully demonstrated a deep-space optical comms link, establishing a connection between Psyche and a newly developed ground segment in Greece over 265 million km SpaceX conducted their 500th Falcon launch, and is seeking a $400B valuation (the record valuation of a privately held US company) in their next insider share sale Over 2,000 NASA employees, mostly specialized senior staff (a huge brain drain), are departing the agency due to pressure from federal budget cuts Japanese launch startup Interstellar Space raised a $61.8M Series F to boost development of their Zero rocket, set to debut in 2027 Taiwanese private launch company TiSpace terminated the inaugural suborbital flight of its hybrid-fueled VP01 rocket shortly after lift-off South Korean launch startup Innospace qualified the second stage of its first commercial launch vehicle ‘HANBIT-Nano’ Firefly filed an S-1 prospectus with the SEC in order to IPO soon Varda Space raised $187M to expand their in-space pharmaceutical research CisLunar Industries raised $1M in seed funding to scale production of their power processing units (PPUs) Chinese scientists proposed sending a spacecraft to Neptune, a 16-year journey featuring a gravity assist around Triton before orbital insertion in 2049 Sean Duffy, the US Secretary of Transportation, has been appointed “interim” NASA administrator Axiom-4’s crew dragon spacecraft undocked from the ISS and splashed down on Tuesday—commander Peggy Whitson extended her record as longest American and woman in space to a total of 695 days.
 
 

The SpaceX Dragon spacecraft carrying the Ax-4 crew docked to the ISS’s Harmony module, with the Canadarm2 robotic arm and its latching end effector visible.

Etc.

On its way to asteroid 469219 Kamoʻoalewa (and then to comet 311P/PANSTARRS), China’s Tianwen-2 probe captured this image looking back at Earth from a mere 590,000 km away. The probe will attempt to collect samples from Kamoʻoalewa when the object is about 41,000,000 km away from Earth.