Dear friends,
Exciting space-related news have emerged in recent weeks. First, came the discovery of what may be the closest habitable planet ever found, Ross 128 b. This planet has a minimum mass of 1.4 Earth masses and is thought to be rocky. It orbits a relatively stable host star that is about 1/280 less luminous than the Sun at a distance that is about 1/20 the Earth-Sun distance. Ross 128 b receives an amount of light that is higher than but comparable to that received by Earth. It may have an atmosphere and its temperature may allow for water to exist in liquid form on parts of its surface. In many ways, it is similar to Proxima Centauri b, but it orbits a quieter star and is therefore more likely to be habitable. It is astounding that a potentially habitable planet has been found around the nearest star to us, Proxima Centauri, only 4.2 light years away, and now around Ross 128, only 11 light years away. Our galactic backyard may be home to several habitable planets.
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Artist's impression of Ross 128 b. Source: European Southern Observatory (ESO).
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Next, came the discovery of the first known interstellar asteroid, initially designated 2017 U1. After the interstellar nature of this object was confirmed — observations showed that it was not bound to the Sun on either the inbound or outbound legs of its foray into the Solar System — a new class of objects was established by the International Astronomical Union (IAU), and the object became known as 1I/2017 U1, where "I" stands for interstellar and "1" stands for the first member of the class. The discovery team then proposed the Hawaiian name ʻOumuamua, which was accepted by the IAU's nomenclature committee. 2017 U1 did not develop any cometary activity as it approached the Sun, indicating the absence of near-surface ice, an observation that many astronomers found surprising. Because of the relative abundance of elements, the general expectation is that there are many more icy bodies (i.e., comets) than rocky bodies (i.e., asteroids) in the universe. So most interstellar visitors are expected to be icy bodies. The lack of cometary activity suggests that (1) we noticed the passage of an asteroid (unlikely but not impossible), (2) 2017 U1 was originally a comet that became desiccated (i.e., extinct) because of previous heating episodes, or (3) a mantle of insulating material, perhaps emplaced by long exposure to cosmic rays, prevented interior ice from sublimating. The available data are consistent with any one of these hypotheses. A far more exotic hypothesis is that 2017 U1 did not develop cometary activity because it is a spacecraft built by an alien civilization. I am skeptical about this latter hypothesis given the physics of interstellar travel. The object was observed by SETI scientists with the Green Bank Telescope and the Allen Telescope Array, but nothing unusual was reported. Perhaps the most regrettable aspect of the 2017 U1 encounter is that the Arecibo radar was not operational in the aftermath of Hurricane Maria, preventing us from observing the object with radar. A radar detection would have provided valuable information about the reflectivity, size, shape, and spin state of 2017 U1.
A few weeks later, the news media reported details about a former program funded by the U.S. government to study unidentified flying objects (UFOs). The "Advanced Aviation Threat Identification Program" was run by the Defense Intelligence Agency and cost about $22 million over a five-year period (2007-2012). It is understandable that the U.S. would want to gather intelligence about the defense capabilities of other nations. However, the program's director and the primary contractor have both made claims suggesting that extraterrestrials have visited Earth, and it appears that the effort was focused on finding evidence of E.T. flying in Earth's atmosphere. SETI provides much better chances of identifying extraterrestrial civilizations than a search for UFOs because, unlike spacecraft, radio waves can travel at the speed of light, can propagate in multiple directions, and don't need maintenance. Yet, the U.S. government has not funded SETI research in over two decades.
From my perspective, the most exciting recent news is that UCLA graduate student Paul Pinchuk has decided to devote part of his research time to SETI. Paul took the SETI course in Spring 2017 and passed his Physics Qualifying Examination in Fall 2017. Since then, he has already made important contributions to our data analysis efforts and I very much look forward to continuing my work with him.
We are now seeking to secure sufficient funds to expand our data storage capabilities and once again provide an observing experience during the third offering of the UCLA SETI course in Spring 2018. I am extremely grateful for the generous support of our donors, who enable an impactful and memorable learning experience.
Warm regards and best wishes for a happy new year,
Jean-Luc Margot
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