Art imagination of Oumuamua (Credit: ESO and M. Kornmesser)
In 2017, astronomers discovered an uninvited guest within the solar system: the interstellar rock Oumuamua, the first time humans have observed objects from outside the solar system entering the solar system. However, some of Oumuamua's peculiar properties seem to suggest that it is not naturally formed, and some scientists even boldly speculate that it is an alien spacecraft that broke into the solar system to collect information near The Earth. Now that Oumuamua has moved beyond the orbit of Neptune, in order to unveil its true face, some scientists have proposed that a probe should be launched to catch up with Oumuamua and take pictures of it...
On October 18, 2017, Hawaii's Pan-STARRS telescope observed a peculiar object: a cigar-shaped rocky asteroid about 100 meters in diameter rushing into the solar system from the direction of the constellation of Lyra. The object has hyperbolic orbital velocities of up to 26 kilometers per second (as the distance from the Sun approaches infinity), and the interactions of the objects in the Solar System cannot provide such high kinetic energy, and the Sun's gravitational pull cannot capture such fast objects. As a result, scientists speculate that Oumuamua comes from outside the solar system. This is the first time that humans have found objects from outside the solar system in the solar system.
This uninvited visitor to the solar system was named "Oumuamua," which means "scout" in Hawaiian. Oumuamua's orbit is not closed ellipsoid, but open, meaning it does not return periodically like Halley's Comet. Oumuamua skimmed Saturn's orbit in January 2019 and is now estimated to be somewhere beyond Neptune's orbit, heading towards the constellation Pegasus. However, some of Oumuamua's properties suggest that it may not be an ordinary interstellar object, and some scientists even suspect that it is an alien spacecraft. In order to unveil its true face, some people now plan to launch a probe to catch up with Oumuran in 2028 and take a close photo of it.
Alien spacecraft?
In June 2018, astronomers at the European Space Agency discovered that beyond the gravitational pull of the sun and planets, there was a faint force slowly pushing Oumuamua. Scientists are curious about the source of this force. Later, scientists Shmuel Bialy and Avi Loeb of the Harvard-Smithsonian Center for Astrophysics proposed that this extra force might come from daylight. However, if Oumuamua is to be propelled by sunlight like a light sail, it is either very thin in itself, like a layer of polyester film, or very low in density. Is this really the shape of Oumuamua? Scientists are not yet sure.
If Oumuamua is a naturally formed interstellar rock, it will also bring a difficult problem. Loeb collaborated with Amaya Moro-Martín and Ed Turner in a 2009 paper calculating the number of interstellar rocks. The article builds on our understanding of the solar system and the assumption that these stones are from solar-like planetary systems orbiting other stars. But to explain the emergence of Oumuamua, the number of interstellar rocks in the required unit volume far exceeded expectations, and exceeded several orders of magnitude. If all of Theomuamua-like objects are distributed on random trajectories and have equal probabilities of moving in all directions, then there should be a thousand trillion such objects in the solar system at any given time.
Image source: Pixabay
So Loeb and other scientists wondered if OuMuamua would be a flying machine made by an alien civilization. If Oumuamua had created the solar system to collect data from habitable areas near Earth, the number of such objects could be reduced to a reasonable range. In this case, Oumuamua's thin, flat shape may indicate that it is a receiver that receives data from probes that have long been scattered on Earth. And it is not propelled by sunlight to gain power, it is just a side effect of its shape.
Although the idea of Oumuamua being an alien spacecraft is not mainstream in academia, the questions surrounding it still arouse the curiosity of astronomers. What is oumuamer made of? Can it really be pushed by light pressure? Unfortunately, however, because Ofumua is moving so fast, it is difficult for even the largest telescope to observe it a few months after its discovery. Now some scientists have come up with a bold idea: launch a probe to catch up with Oumuamua and take a picture of it.
Catch up with Omuamua
In a paper published recently on the preprinted website, scientists from the British nonprofit Initiative for Interstellar Studies and space Initiatives Inc in the United States proposed specific options for catching up with Oumuar. If this is implemented according to this plan, the spacecraft launched from Earth in 2028 will catch up with Oumuar in 26 years and take pictures of it for astronomers to study.
The researchers refer to this scheme as the "Jupiter Oberth maneuver." According to the plan, the probe will be launched from Earth in 2028 and then orbit Venus and Earth in turn. This minimizes the fuel for the probe to sail to Jupiter, the researchers say. About four years later, the probe entered the orbit of Jupiter, which would burn fuel and accelerate, flying toward Oumuamua at a speed of 133,200 kilometers per hour under Jupiter's gravitational slingshot effect. After that, the probe will sail for nearly 18 years, eventually approaching Oumuamua around 2050.
Schematic diagram of Jupiter Olbers strategy (Image source: original paper)
The plan sounds eye-catching, but whether it will be approved is unknown. Every decade, NASA publishes a Decadal Survey white paper that summarizes the ideas and priorities of space research for each mission. Proponents of the idea of catching up with Oumuamua have submitted their proposals to NASA, hoping to get encouragement from the scientific community. If the plan does work, hopefully, more than two decades later, someone will remember that a strange object suspected of being an alien spacecraft broke into the solar system.
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bibliography
https://www.scientificamerican.com/article/a-possible-link-between-oumuamua-and-unidentified-aerial-phenomena/
https://www.livescience.com/oumuamua-mission-plan
Global Science November 2020, OuMuamua: The Bizarre Interstellar Invaders