¶Do the Beta Taurids hold more Tunguska-scale impactors? The Taurid meteor shower which stretches from October into November occurs when the Earth passes through the trails of dust, micrometeoroids, and other debris from the comet Ecke and the asteroid 2004 TG (which itself might be a large fragment of Ecke). This trail of debris has a 7:2 resonance with the orbit of Jupiter which has caused it to spread out into a large stream, believed to represent the largest such stream of matter in the inner solar system. While we move through the stream heading away from the Sun in October/November, we also intersect with the stream in June/July while we are headed toward the Sun, making it mostly invisible—this cross section of the stream is known as the Beta Taurids. In 2019, new models suggested that the Tunguska event (June 30, 1908) closely matched the timing and trajectory of an object originating from the Beta Taurids. Models suggest that Tunguska-scale events should be very infrequent, occurring every 1,000 to 10,000 years (cf. all the way back to Issue No. 20 for more). However, if the Beta Taurids contain additional 100m+ asteroids, it could be one of the only concentrated sources of Potential Hazardous Objects (PHOs)—and, a source we’d have trouble detecting PHOs from because of glare from the Sun (paper). This year's primary Taurids started on Tuesday and an observation campaign to characterize their potential for hiding more PHO-scale objects is underway. Related: If you'd like to join the Global Meteor Network, you can start with a RaspberryPi and buy or hack together an all-sky meteor camera. ☄️
Earth’s path as it passes through this year’s Taurid meteor stream.
¶Space science as a service. Blue Skies Space (BSS), a UK- and Italy-based startup offering commercial science missions in partnership with ESA, announced their upcoming Mauve satellite. Mauve will observe nearby stars which may host exoplanets for stellar flare activity, studying how those energetic events affect the habitability of their planets. (Our Sun is an unusually quiet star, and the massive flares that are more common elsewhere may make the evolution of life challenging.) Mauve will carry a UV spectrometer and a 15 cm telescope. BSS is also working on a second satellite, Twinkle, which will spend seven years spectroscopically observing exoplanet atmospheres and bodies in our solar system. We think BSS’s “space-science-as-a-service” subscription model is quite interesting and is distinct from hosted payload providers like Loft Orbital which provide space-as-a-service, but don’t generally design the payload or mission CONOPS itself. We’d love to hear about other companies with similar business models.
¶Papers (about stellar cataclysms).
- A Sun-sized star has been spotted tightly orbiting (and accreting onto) a white dwarf with a period of only 51 minutes (paper). This is the most rapidly orbiting “cataclysmic variable” binary system seen yet.
- Meanwhile, Gaia BH1 is a bright, also Sun-like star in an eccentric orbit around something heavy (9.8 solar masses) and invisible… it seems like it could be a dormant black hole, without an accretion disk (paper).
- Relativistic jets of matter from a pair of colliding neutron stars were measured by Hubble to be moving at greater than 99.97% the speed of light (paper). The event, dubbed GW170817, was observed in August 2017 and was the first time we’ve detected both gravitational waves and gamma radiation from a binary neutron star merger, followed up by 70 additional observations made from Earth and space.
- A pair of orbiting black holes has shown a precession effect predicted by general relativity (paper). One of the pair, about 40 times more massive than our Sun, is spinning so rapidly that it distorts spacetime and causes the binary system’s orbit to wobble back and forth, precessing several times per second. The spinning black hole is rotating almost as fast as is physically possible according to our current theories.
- On October 9th, orbiting X-ray and gamma-ray telescopes detected a record-breaking gamma-ray burst (GRB), likely the result of a supernova and black hole formation. GRB 221009A was 10-100 times brighter than previously observed GRBs. This event, which was fortunately 2.4 billion light-years away (still considered close for a GRB), was so powerful that it created detectable ionospheric disturbances in Earth’s atmosphere. That's nuts. If such a burst occurred within the Milky Way it could be powerful enough to damage the ozone layer. 💥
¶News in brief. Following its mostly-successful first orbital launch, Firefly has added former NASA Administrator Bridenstine to its board of advisors ● The third and final Tiangong space station module was rolled out to the pad atop its Long March-5B—launch is expected October 31st ● The ISS had to thrust for 5 minutes to avoid debris from the November 2021 Russian ASAT test (again) ● Starlink launched an aviation service offering ● The first Falcon Heavy launch since 2019 is NET Oct 31 ● NASA bought three more Orion spacecraft from Lockheed Martin for the Artemis VI, VII, and VIII missions, totaling $1.99B ● The European Commission announced €200M in funding for 49 space-related projects ● Orbex closed a £40.4M Series C—the company’s upcoming two-stage, biofuel-based Prime vehicle is designed to take 180 kg to LEO ● An Indian LVM3 delivered 36 OneWeb satellites to orbit, the country’s heaviest payload to date—unfortunately it looks like future OneWeb launches are pushing back the launch of Chandrayaan 3 ● Ariane 6 has been delayed again, until the end of 2023—ESA’s Hera and Euclid missions will now launch on Falcon 9s, with JUICE slated for the first Ariane 6 launch ● YASL with 54 Starlink satellites on board in SpaceX’s 48th launch of the year (in 43 weeks)—there are now 3,100 active Starlink satellites, more than all other active sats combined ● NASA ISS spacewalks will resume after analysis of the March 23rd leaking space suit found no specific hardware flaw ● Jim McDivitt, commander of Gemini 4 and Apollo 9, passed away at 93—Universe Today has a remembrance.
- A detailed writeup of the 1994 Long March 3B Intelsat disaster, possibly the worst (and least well-known) rocket launch failure in history. Official reports stated 2 deaths and 57 injuries, but many believe this only included launch site personnel and deaths among villagers may have reached into the hundreds.
- The scary sound of Earth’s magnetic field.
- SpaceX recently announced changes to their rideshare program, lowering the minimum booking size to 50 kg starting in 2024. “Now, even though the price per kg remains the same, the minimum contract price is now just $275k. Not only that, they invite you to buy the slots and book the launch directly with them. In one fell swoop, SpaceX has challenged the ‘buy in bulk, divide, and conquer” business model’ of aggregators like D-Orbit, ExoLaunch, Momentus, and Spaceflight. There’s still value in last-mile orbital tug-based delivery, but simply bundling and releasing smallsats may soon become a non-viable business model.
- Tianwen-1 is China’s successful Mars mission. Tianwen-2, in 2025, will be a sample return mission to near-Earth asteroid Kamo’oalewa (technically a quasi-satellite of Earth). Tianwen-3 is China’s ambitious Mars sample return mission targeting a 2028 launch (cf. Issue 175). Now we know about Tianwen-4: a double-spacecraft mission to orbit Jupiter’s moon Callisto while a second smaller craft heads on to Uranus. It would be only the second spacecraft (after Voyager 2) to visit Uranus. NASA is also considering a Uranus mission design. The “Tianwen” series of missions are named after a 2,300-year-old poem, “Heavenly Questions”. Related: even more speculative missions are being explored, such as a trip to Ceres and a massive space telescope.
- Speaking of Uranus, we now have a theory on why it’s tilted 98 degrees: computer models suggest that if a large moon entered orbit around the planet sometime in the past, it could have gravitationally destabilized the planet enough to tilt the system dramatically, before ultimately crashing into the ice giant. 🪐