¶The (Bob)cat’s out of the bag. Bobcat-1, a CubeSat developed at Ohio University (OU) and manifested for flight through NASA’s Educational Launch of Nanosatellites (ElaNa) Mission 31, launched last month from Wallops Flight Facility on Cygnus NG-14. Bobcat-1 is OU’s first CubeSat and has a primary mission to demonstrate the estimation of global navigation satellite system (GNSS) inter-system time offsets from measurements made in LEO. GNSS systems such as GPS (US), GLONASS (Russia), Galileo (EU), and BeiDou (China) each operate on independent time scales, and the offsets between these time scales are some of the most significant biases to be accounted for in a multi-system solution. Estimating inter-system time offsets is a crucial part of creating an inter-operable worldwide GNSS service, which is of particular benefit to users with limited GNSS visibility, such as terrestrial users in urban canyons or space vehicles orbiting at a higher altitude than typical GNSS satellites (e.g. GEO/HEO satellites receiving signals across Earth’s limb). Bobcat-1’s short orbit period will enable visibility of all navigation satellites within a small time frame, allowing for frequent measurements of satellites from all major positioning constellations. Measurements that are taken in orbit avoid many terrestrial error sources like signal propagation delay through Earth’s atmosphere and multipath reflection from terrain and buildings. Measurements from the CubeSat’s onboard GNSS receiver will be downlinked and then post-processed. Bobcat-1 was deployed from the ISS at 4:05 AM EST on November 5, 2020, along with the University of Georgia’s SPOC CubeSat. Since deployment, Bobcat-1 has been tracked by ground stations across the planet, enabled by the SatNOGS network of amateur satellite ground stations, including one on top of OU’s engineering building. Bobcat-1’s SatNOGS data dashboard is available here. — Brian Peters & Kevin Croissant, students on the Bobcat-1 team (follow Bobcat-1 on Twitter). |
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¶What is Biden’s space policy? With the United States’ election of Joe Biden as its next president, we expect to see some changes in NASA’s focus. A return to a prioritization of Earth and climate science can be expected, much to our relief. We also assume that Biden will continue promoting commercial space programs—something he helped see to initial successes during the Obama Administration. What we’re much less confident about is the future of the Artemis missions—a slip from the 2024 target is basically inevitable, but a reversion to a 2028 timeline would be disappointing. What we do know is that NASA Administrator Jim Bridenstine has publicly announced his intention to leave the role under Biden, but there may be a small possibility of him continuing on—we feel he’s been one of the most successful appointees of the current administration and wouldn’t mind him staying. (Related: Potential budget cuts under the new administration may jump to mind since the current budget includes significant Artemis-related line items. However, NASA budgets have generally fared slightly better under Democratic presidents since the Apollo era, while predominantly following macro-economic trends [paper].) |
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¶Superflares. Many of the 4,301 exoplanets confirmed so far (Ed.: this number is up 5 from when we initially wrote this on 11/4), such as Proxima b (only 4.2 light-years away!), are around M-type red dwarf stars, which seem to frequently harbor Earth-sized rocky worlds and outnumber stars like our Sun tenfold in the Milky Way. Unfortunately, red dwarfs are also very active and are known to emit powerful flares that would bathe planets in UV light (paper) and potentially strip away their atmospheres. As an example, GJ 887, which has 2+ planets (paper), was thought to be unusually calm for a red dwarf, but new research calls that into question, citing detection of hourly flares (paper). The ASU-led Star-Planet Activity Research CubeSat (SPARCS) 6U CubeSat mission will monitor ultraviolet flares and sunspot activity on these incredibly common stars to better understand the potential habitability of planets that orbit them. |
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| ¶News in brief. A Chinese rocket company, Galactic Energy, successfully launched their first orbital rocket, the four-stage Ceres-1, becoming the second Chinese New Space company to achieve orbit (they also secured 200 million yuan in Series A funding); after suspending operations a year ago, Vector Space is back under new investor ownership; in a first, NASA objected to the FCC regarding a proposed satellite constellation (pdf)—SpaceMobile would consist of satellites with 900 m2 antennas for communicating with 5G mobile phones, but NASA is concerned that they would be too close to NASA’s remote-sensing satellites and could present a “catastrophic collision” risk—the company, naturally, disagrees; ESA granted €500,000 contracts to three German small launch startups as part of their Boost! program: HyImpulse Technologies, Isar Aerospace Technologies, and Rocket Factory Augsburg; SpaceX returned non-flight proven Falcon 9 hardware to service, after a brief lacquer-induced hiatus, with last week’s GPS III-SV04 launch; former astronaut Mark Kelly won a US Senate seat in Arizona; a Chinese Long March 6 delivered 13 satellites to SSO, including 10 ÑuSat Earth observation satellites for Satellogic, who now have 21 sats, some of which provide 70 cm resolution imagery; India returned to launch activity with the recent launch of an Earth observation satellite and nine rideshare small sats; and, NASA successfully contacted Voyager 2 using the recently upgraded Deep Space Network. |
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¶Etc.- The current status of SpaceX's Starship & Superheavy prototypes as of 11/1/20.
- Bacteria that use atmospheric hydrogen to break down CO2 for growth, effectively living on air, previously found in the arctic, have now been found on both poles and in the Himalayas (paper).
- A Russian actress will head to the ISS in 2021 to star in a first feature film shot in space.
- DuAxel (video) is a cool design for a rover that can break into two tethered halves for exploring steep terrain.
- We linked offhand last week to a recent study that analyzed Kepler and Gaia data and found that up to half of Sun-like stars could host potentially-habitable worlds. This study is worth a further highlight—a NASA press release reads: “Our galaxy holds at least an estimated 300 million of these potentially habitable worlds, based on even the most conservative interpretation of the results [...]. Some of these exoplanets could even be our interstellar neighbors, with at least four potentially within 30 light-years of our Sun and the closest likely to be at most about 20 light-years from us. These are the minimum numbers of such planets based on the most conservative estimate that 7% of Sun-like stars host such worlds. However, at the average expected rate of 50%, there could be many more.”
- Additionally, Earth is great and all (and we’d like to keep it that way!), but there are likely planets out there that are even more hospitable to life. A recent survey selected 24 “superhabitable” planets out of the >4.000 known exoplanets that are a little warmer, a little older, and a little larger than Earth and orbit longer-lived and more stable stars. These make great observing targets for next-generation telescopes like the JWST.
- Related to the mention of SpaceX’s Starlink TOS Mars sovereignty clause from last week: Mars is not a legal vacuum.
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