¶Ramses, ESA’s mission to Apophis. ESA recently announced Ramses, a mission to rendezvous with 99942 Apophis when it passes inside the GEO belt to within 32,000 km of Earth in 2029. The mission will launch in April 2028, only two months before rendezvous and just in time to observe the asteroid during its closest approach to Earth. Ramses will watch the NEO for structural changes due to gravitational forces and infer details about its composition, interior structure, cohesion, and other properties. Richard Moissl, the head of ESA's Planetary Defence Office, also points out that Ramses’ fast(ish) turnaround from approval to launch will help demonstrate humanity’s ability to quickly survey a newly discovered, potentially hazardous object in the future (although 4 years is hardly a Bruce Willis-in-Armageddon-speed response). Catching up with Apophis after the encounter will be OSIRIS-APEX (neé OSIRIS-REx) and maybe the mothballed Psyche Janus probes, while a number of other missions, some private, are also being considered. We wrote more about upcoming planetary defense missions in Issue № 275. |
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 | Goldstone radar observations of Apophis in March 2021, during its last close approach to Earth before 2029, ruled out an Earth impact for at least a century. (Unless any spacecraft bump into it too aggressively in 2029…) |
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¶WOW, but probably not special. The WOW! Signal, detected on August 15, 1977, is an unexplained radio source near the 1420 Mhz hydrogen line, received by the OSU ‘Big Ear’ radio telescope. Like any potential technosignature, it should be viewed with skepticism and most likely originated from some poorly understood phenomena or interference (space debris, an Earth-based signal, a passing flying saucer, etc.). Ohio State University’s Big Ear was a single axis telescope, only able to change its azimuth. Any signal with a fixed origin in the sky would grow and then fade as the Earth turned and Big Ear scanned across the signal source. The WOW signal followed this pattern, rising to a peak of 30 σ above background noise. Its origin came from the direction of Sagittarius, but due to Big Ear’s two-horn receiver design, there are two areas the signal may have originated from based on which horn actually detected the signal (which can’t be determined from the data). The signal was thought to have been explained in 2017 as two comets that were coincident with the signal’s detection, but these have since been proven unlikely to be the source. Other potential technosignatures have regularly been found and disproven, such as SHGb02+14a (no candidate stars near the origin and a frequency drift that would indicate a planet rotating 40x the speed of Earth), HD 164595 (only detected once with a frequency sometimes used by military satellite downlinks), and BLC1 (c.f. Issue № 96). BLC1, in particular, seems unlikely, as its source would have been Proxima Centauri. Based on the Copernican principle, having a radio-transmitting civilization right next door (in galactic terms that is, since space is BIG) would be eight orders of magnitude greater than predicted by the principle (paper)—the panspermia hypothesis might attempt to explain this surprising proximity, but the relative motion of Proxima Centauri to Sol (22 km/s toward us) makes it a “new” neighbor on the timescale of life on Earth. Since 1977, the WOW signal has been searched for multiple times unsuccessfully, meaning it doesn’t meet the SETI Institute requirement of a second telescope confirming any signal. This could be because the transmission was short-lived, rotated out of view, or most likely, was terrestrial or erroneous. Recent work on WOW includes a null result for one candidate origin system (2MASS 19281982-2640123) and a project searching for similar technosignatures from other star systems in archived Arecibo data (which will release its first findings on August 15th, 47 years after the detection). But, based on SETI’s revised Rio scale for rating the importance of potential extraterrestrial signal detection events, WOW doesn’t even cross the threshold to being a 1 (insignificant) out of 10. |
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 | Jerry Ehman identified this signature while reviewing data by hand as a SETI volunteer in 1977, writing ‘Wow!’ on the data sheet (left); the signature plotted against background noise (right). |
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| ¶News in brief. SpaceX Falcon 9 returned to flight with three Starlink launches in 30 hours after only 15 days of being grounded due to its recent upper-stage anomaly (a brittle, and presumably cracked, pressure monitoring line) and conducted its 300th reflight of a booster ● Boeing performed a hot fire test of the 27 RCS thrusters aboard the docked Starliner, which could be the last test before the spacecraft’s delayed return to Earth is approved ● ABL Space Systems suffered “irrecoverable” damage to an RS1 rocket intended for their second launch attempt, caused by a residual pad fire that started during a preflight static fire test ● Astranis raised a $200M Series D to build their next-generation microGEO communications satellites, aiming to increase the satellite’s bandwidth by 5x at the same size ● A NASA committee concluded that it will be impossible to continue operating the Chandra X-ray Observatory under the proposed 2025 budget, due to a billion-dollar shortfall in agency science funding (SaveChandra!) ● iSpace Europe completed their European designed, manufactured, and assembled lunar micro rover ahead of its shipment to Japan for integration into the HAKUTO-R Mission 2 lunar lander ● SpaceX is moving Crew Dragon splashdown and recovery operations from Florida to the West Coast to reduce the risk of renentering debris hitting land ● Star Catcher raised a $12M Seed round to develop satellites with large solar arrays and lasers to transmit energy to solar panels on existing satellites (these will need to combine at least three wavelengths of light to support the triple junction panels used by most LEO spacecraft)—others working on similar space-to-space power beaming include Space Power, Litepulse, Photonicity, Aquila, and Powerlight ● New Frontier Aerospace, a startup building a suborbital point-to-point vehicle, started testing their small-scale Mjölnir full-flow staged combustion engine rated at 1.3 tons of thrust ● India is allocating $1.56B to their Department of Space (with majority of funds going to the ISRO) in 2024, an 18% increase from 2023 (According to Jatan, this is less significant than it sounds given that budgets were significantly underspent last year and likely rolled forward) ● Sierra Space conducted the second full-scale burst test of their inflatable module for the Orbital Reef commercial space station, inflating the 300-cubic-meter module until it burst at 74 psi (NASA’s recommended level is 60.8 psi, the expected maximum operating pressure of 15.2 psi multiplied by four for added safety). |
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 | Sierra Space’s inflatable space station module exploding at 74 psi as part of their second full-scale burst test |
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¶Etc.- ESA also recently approved LUMIO, the Lunar Meteoroid Impacts Observer, a cubesat that will watch the lunar surface for meteorite impacts, the rate of which is poorly known and which obviously pose a threat to future lunar infrastructure and habitation. Targeting 2027, the mission will autonomously orbit the Earth-Moon L2 to watch the lunar farside.
- Some gorgeous slo-mo footage of Starship’s 6 engines during a recent static fire ahead of flight 5.
- After 14+ successful years in space, NASA’s NEOWISE (Near-Earth Object Wide-field Infrared Survey Explorer) spacecraft will stop surveying the skies on July 31st before being commanded into hibernation a week later. This spacecraft’s retirement is due to its descent to a low altitude, which cannot be corrected without a propulsion system, compounded by the effects of the solar maximum.
- The UK Space Agency invested £24M into eight early-stage space projects, including HyImpulse (suborbital testing from SaxaVord spaceport), Rolls Royce (fission microreactor), startup SuperSharp (thermal imaging telescope), Lunasa (satellite docking), Spire (weather forecasting data), ETL Systems (ground equipment linking satellites with 5G and 6G mobile networks), Orbit Fab (further development of their satellite refueling tech), and Wayland Additive (electric propulsion). There were additionally another 15 ‘Kick Starter’ projects receiving £9M total.
- Footage of the moments before, during, and after the Arecibo Radio Telescope collapse.
- Eric Berger writes in ‘SpaceX just stomped the competition for a new contract—that’s not great’ about how SpaceX is dominating US commercial space, winning on price and reliability (both good things!), but also starting to become a sole source provider when more competition would be better long term.
- Satcat is a database of real-time satellite, debris, and space weather info from Kayhan Space.
- A methane leak in Kazakhstan observed via satellite released 131 ± 34 kilotons of methane (paper), larger than any known prior release. As methane’s 100-year impact is about 28x CO2, this is something like 3.7 megatons of CO2e. Meanwhile, two days last week were the hottest days for the planet on record with the planet’s average surface air temperature reaching 17.15 °C, and the EU’s Copernicus Climate Change Service reports an average global temperature of 1.5 °C above pre-industrial levels for the last 12 consecutive months, and the hottest June on record, now the “13th month in a row that was the warmest in the ERA5 record for the respective month of the year.”
- Faxes From the Far Side: the 1950s-era Soviet mission to first photograph the far side of the Moon.
- Videos of confused baby quail trying to fly in space, for science.
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Hubble in front of the Moon from the perspective of Space Shuttle Endeavor during the first Hubble servicing mission in 1993. |  |
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