Observable tests for the light-sail scenario of interstellar objects
arXiv:2208.13818 · doi:10.1051/0004-6361/202244119
Abstract
We scrutinize the light sail scenario of the first interstellar object (ISO) 1I/2017 U1 (`Oumuamua) by making comparisons between physical models and observational constraints. These analyses can be generalized for future surveys of `Oumuamua-like objects. The light sail goes through a drift in the interstellar space due to the magnetic field and gas atoms, which poses challenges to the navigation system. When the light sail enters the inner solar system, the sideways radiation pressure leads to a considerable non-radial displacement. The immensely high dimensional ratio and the tumbling motion could cause a light curve with an extremely large amplitude and could even make the light sail invisible from time to time. These observational features allow us to examine the light sail scenario of interstellar objects. Our results show that the drift of the freely rotating light sail in the interstellar medium is au even if the travel distance is only 1 pc. The probability is < 1.5\% for the expected brightness modulation of the light sail to match with `Oumuamua's observed variation amplitude ( 2.5 -- 3). In addition, the probability is 0.4% for the tumbling light-sail to be visible (brighter than V=27) in all 55 observations spread over two months after discovery. Radiation pressure could cause a larger displacement that is normal to the orbital plane for a lightsail than that for `Oumuamua. Also, the ratio of anti-solar to sideways acceleration of `Oumuamua deviates from that of the light sail by ~ 1.5σ. We suggest that `Oumuamua is unlikely a light sail. The dynamics of an intruding light sail, if exist, has distinct observational signatures, which can be quantitatively identified and analyzed with our methods in future surveys.
arXiv comment17 pages, 13 figures Comments are welcome
References in corpus (27)
- REBOUND: An open-source multi-purpose N-body code for collisional dynamics
- REBOUNDx: A Library for Adding Conservative and Dissipative Forces to Otherwise Symplectic N-body Integrations
- Interstellar Interloper 1I/2017 U1: Observations from the NOT and WIYN Telescopes
- Dusty gas with SPH - I. Algorithm and test suite
- Interstellar Interlopers: Number Density and Origins of 'Oumuamua-like Objects
- The Natural History of 'Oumuamua
- Spitzer Observations of Interstellar Object 1I/`Oumuamua
- Col-OSSOS: Colors of the Interstellar Planetesimal 1I/`Oumuamua
- The origin of interstellar asteroidal objects like 1I/2017 U1 'Oumuamua
- APO Time Resolved Color Photometry of Highly-Elongated Interstellar Object 1I/'Oumuamua
- The tumbling rotational state of 1I/`Oumuamua
- Implications of the interstellar object 1I/'Oumuamua for planetary dynamics and planetesimal formation
- Modeling the light curve of `Oumuamua: evidence for torque and disc-like shape
- On the rotation period and shape of the hyperbolic asteroid 1I/`Oumuamua (2017) U1 from its lightcurve
- Implications for planetary system formation from interstellar object 1I/2017 U1 (`Oumuamua)
- 1I/`Oumuamua as a Tidal Disruption Fragment From a Binary Star System
- Tidal fragmentation as the origin of 1I/2017 U1 ('Oumuamua)
- Could 1I/'Oumuamua be an icy fractal aggregate?
- Interstellar object 'Oumuamua as an extinct fragment of an ejected cometary planetesimal
- 1I/'Oumuamua as an N2 ice fragment of an exo-Pluto surface: I. size and compositional constraints
- The interstellar object 'Oumuamua as a fractal dust aggregate
- Evidence Suggesting that 'Oumuamua is the ~30 Myr-old product of a Molecular Cloud
- Turbulent power spectrum in warm and cold neutral medium using the Galactic HI 21 cm emission
- Interstellar Asteroid Rotation with the Mechanical Torque Produced by Interstellar Medium
- Evidence against non-gravitational acceleration of 1I/2017 U1 `Oumuamua
- Oumuamuas passing through molecular clouds
- 'Oumuamua as a light sail -- evidence against artificial origin