One of the first profiles ofIt's been published, and it looks almost like most other comets. What doesn't look like is the first interstellar object, , which made its closest passage through the Earth exactly two years ago today.
The paper, published Monday in Astronomy of Nature, shows early data on Borisov, which is only the second object to visit our solar system so far. While scientists will get a better look as the comet gets closer to Earth in the next few weeks, so far it looks to be the same color and size as most ordinary comets. Previous research has also revealed that it refers to known tail modes that contain some of thewe expect interstellar comets.
"We immediately noticed the known coma and tail that were not seen around Oumuamuwa," said Michal Dahrus of Jagiellonian University in Poland, who led the study. "This is really interesting because it means that our new visitor is one of these mythical and never before seen 'real' interstellar comets."
The implication here is that Omuayama was not a "real" interstellar comet, which then leads to the obvious question: So what is the bad one?
Your basic comet, a category that includes Borisov so far, is a typically spheroidal mass of rock and ice that starts to extinguish as it is heated by the sun, producing its characteristic coma or tail. Omuamu was a heavy cigar-shaped table that didn't show many signs of gas or coma. Even strange was the fact that it seemed to accelerate as it flew back into deep space.
We can never look at Oumuamua because it was first observed five days after its close access, already out of the solar system.
Many astronomers now believe that interstellar visitors may be more frequent than previously thought. Our technologies and techniques are only finally sufficiently refined to detect them. As such, we should expect to find many more stars from other stars spinning around our neighborhood over the coming years. We may notice more elongated or odd interplanetary space rocks and conclude that Oumuamu was not very strange.
Or it may not, which may give credence to the idea proposed by the respected astronomer Harvard, Avi Loebfrom another civilization. The idea has earned Loeb some critique, and it's an easy idea to drift on to an object we probably will never see again.
But Lob thinks we may be able to find evidence of life from other star systems at a much closer location: the Moon.
"The idea is to consider the surface of the Moon as a fishing net for interstellar objects collected over time," he wrote in a column for The American Scientist last month.
Lobb argues that if interstellar objects are commonplace, some of them are likely to crash into the moon at some point, leaving well-preserved debris that may even carry the building blocks of other critics.
"Identifying biomarkers from the remnants of material that comes from the zone that can reside around other stars will inform us about the nature of alien life," writes Lob. "The fundamental question is whether distant life resembles the biochemical structures we find on Earth. The similarities can mean that there is a unique chemical pathway to life everywhere or that life is transmitted between systems. "
He goes on to evaluate the case that a lunar research base for the search and study of such ancient, interstellar fossils could represent a major shortcut in the search for ET. compared to undertaking generational missions to visit other stars.
It's been two years since Oumuamuwa visited us, and now it seems to be harder than ever. Even if we never see that strange flying cigarette again, her cousins could be in now. In fact, Lob also claims we already are.
Bottom line: Our solar system has probably been receiving interstellar visitors for a very long time. Now that they have finally caught our attention, we can learn how diverse (and perhaps even lively) a group they really are.