¶Papers- Gaps in protoplanetary disks due to planetary formation have been observed before, but until a recent JWST and ALMA observation, we hadn't seen the earliest stages of planet formation. The duo spotted the signature of warm silicon monoxide gas and crystalline silicate minerals, which indicate materials solidifying out of the protoplanetary disk, about 2 AU from the still-growing orange dwarf star HOPS-315 (paper). In a million years, the star’s hot gas inflows will have brought it to about the same mass as our Sun (it's at about 60% right now). Related: Also check out these amazing photos of protoplanetary disks around binary stars.
- Explaining why rovers get stuck in sand in low-gravity environments, like the Moon and Mars, requires understanding how sand grains themselves interact in low gravity. “On Earth, sand is more rigid and supportive — reducing the likelihood it will shift under a vehicle’s wheels. But the moon’s surface is “fluffier” and therefore shifts more easily — meaning rovers have less traction, which can hinder their mobility.” Computational models of sand in lower gravity (using the open source Project Chrono simulation engine) show that gravitational offsets (suspension systems) or light-weighted rover models during terrestrial testing are insufficient to predict how wheels will actually behave on arrival (paper).
- Type Ia supernovae are the primary source of iron in the Universe (and also a standard candle for our understanding of cosmology). They occur when a white dwarf star slowly accretes material from an orbiting stellar partner until it passes the Chandrasekhar limit and collapses, creating a supernova with a consistent brightness. However, some Type Ia supernovae may be better explained by a ‘double detonation,’ where “[the] white dwarf forms a blanket of stolen helium around itself, which can become unstable and ignite. This first explosion generates a shockwave that travels around the white dwarf and inwards, triggering a second detonation in the core of the star—ultimately creating the supernova.” This type of event should produce two separate shells of calcium atoms in the debris, and a first example (below) has now been spotted by ESO’s VLT (paper).
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 | The first visual evidence of a star having undergone a double detonation Type Ia supernova. The calcium layers are shown in blue in supernova remnant SNR 0509-67.5. |
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¶Dawn keeps giving. NASA’s Dawn Discovery-class mission ended seven years ago when the craft finally ran out of the hydrazine used for its attitude control. But, much like other NASA science missions, the results continue for years after the mission ends. In Dawn’s case, we continue to learn about the two protoplanets the craft visited over its 11-year life. Dawn was the first NASA mission to use ion thrusters to enter orbit around a small celestial object, and was the first spacecraft to orbit two different bodies (other than Earth). Ceres, the largest of the main belt objects (940 kilometers in diameter), was the primary target of the mission, and where the craft spent its final three years. Now, new modeling of the internal thermal dynamics of Ceres suggests that, in addition to the water and carbon (and ~6 million Belters) previously found via Dawn data, upwelling subsurface brine in Ceres’s past was likely to contain dissolved gases from rock in the midst of metamorphosis, heated through radioactive decay (paper). These components are all those thought necessary for basic life to occur. We don’t have any data that suggests Ceres ever developed life, but if it did, it would have been a long time ago, likely ~2-4.5 billion years in the past, when radioactive heating provided enough energy for the whole process to go. |
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 | | Ceres is shown in this enhanced-color rendering of the dwarf planet, generated from Dawn imagery. The bright spot shows salt deposits left over from upwelling liquid earlier in the world’s life. |
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¶Who knew a dingle dangle could be so useful? ESA announced the launch of an interesting demo mission from PERSEI Space: E.T. Pack, focused on flight testing the Spanish company’s propellant-free tether-based propulsion and deorbiting component (another entry in the electrodynamic tether game over the years is Tethers Unlimited, now part of Arka; there’s also J-SPARC, but we’re not sure if it’s still actively being pursued at its new home with BULL Co.). The system energizes its deployed tether to either pull the attached craft into, or push it away from, the Earth's magnetic field—a 5 km tether would deorbit a craft at 2-7 km/day. PERSEI is developing several versions of its tech focused on the small spacecraft market, but is also working on an attachable device that could be slapped onto particularly offensive pieces of space debris for controlled deorbit (one can imagine an RPOD craft installing these on multiple large debris objects during a single mission). E.T. Pack launches aboard a Vega-C in 2026 through the ESA/EU Flight Ticket program, with commercial availability slated for 2027. |
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 | E.T. Pack will demonstrate a kilometer-long conductive aluminum tether when it launches next year. |
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¶News in brief. U.S. Space Command will relocate to Huntsville (with ~1,600 jobs uprooted with the move), reversing a previous decision to keep the temporary headquarters in Colorado Springs ● The White House eliminated NASA labor unions for ‘national security’ ● Orienspace raised an undisclosed amount between $27 million and $124 million (which feels like a pretty big range) ● Amazon’s Project Kuiper secured its first airline deal with JetBlue; service is planned to begin in 2027—project leadership has been excitedly sharing download speeds of 1+ Gbps ● Korea increased their 2026 space budget by 15% to $7.98B ● NASA selected Amit Kshatriya, former head of the Moon to Mars Program, as the new associate administrator, the agency’s top civil service role ● Pittsburgh-based Astrobotic signed a deal with Andøya Space to launch their Xodiac VTVL test vehicle from their launch site in Norway, which could be the first propulsive landing on European soil by an American company ● The FAA granted SpaceX permission to go from 50 to 120 Falcon 9 launches annually at LC40 ● The FAA also started exploring SpaceX’s request for 44 annual Starship launches from the Cape, prompting pushback from concerned Florida citizens and environmentalists ● ExxonMobile will use GHGSat’s spacecraft for methane monitoring ● SpaceX’s Dragon successfully boosted the ISS a little in an initial test burn (c.f. Issue 334) ● Echostar dropped their plans for a direct-to-device constellation and instead sold their S-band spectrum to SpaceX for $17B ● China conducted three launches in just over 36 hours, comprising of a Long March 3C carrying the Shiyan-29 to GEO, a commercial Ceres-1, and a Long March 6A taking a set of satellites to LEO for RF and geolocation missions. |
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 | A Ceres-1 solid rocket from Chinese commercial launch provider Galactic Energy, lifting off from Jiuquan Satellite Launch Center. |
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| “[JWST] captured newborn stars forming in clouds of dust and gas (colored golden and orange in this image) in a star-forming region called Pismis 24. Though these clouds can hide stars by trapping visible light within, in the infrared, the stars shine through the nebula and together appear to be glowing. In the center is Pismis 24-1, an object formerly thought to be a single massive star, now known to be at least two stars. At 74 and 66 solar masses, they are some of the most massive and luminous stars ever seen […]. Cyan indicates hot or ionized hydrogen gas being heated by the massive stars. Dust molecules are represented in orange. Red signifies cooler, denser molecular hydrogen - the darker the red, the cooler the gas.” |  |
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