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Neptune Planet Solar System space isolated

Researchers: There Are Cold Planets Throughout Our Galaxy

They report that there are even cold planets in the Galactic bulge, where it was not certain they would exist

Researchers from Osaka University, using gravitational microlensing, have determined that there are cold planets throughout our galaxy. Cold planets would have average temperatures below the freezing point. The results show that the planetary distribution is not strongly dependent on the distance from the Galactic center. Instead, cold planets orbiting far from their stars seem to exist universally in the Milky Way. This includes the Galactic bulge, which has a very different environment to the solar neighborhood, and where the presence of planets has long been uncertain. “Stars in the bulge region are older and are located much closer to each other than stars in the solar neighborhood,” explains lead author of the study Naoki Koshimoto. “Our finding that planets reside…

Venus against the background of the sun. Elements of this image furnished by NASA

Carl Sagan Institute: Who Can See Us From Outer Space?

Most exoplanets are spotted when they dim a star’s light while crossing it. Earth does the same thing

We’ve all heard of astronomer Carl Sagan’s pale blue dot (Earth from a billion miles away, 1990). But Jaimie Green reminds us at Slate that Sagan (1934–1996) also published a paper in 1993 that looked at Earth from that distance as if it were an exoplanet. What signals would prompt them to suspect life here? That approach is still followed by astronomer and director Lisa Kaltenegger at Cornell University’s Carl Sagan Institute. One question is, where would an intelligent, technologically advanced civilization need to be to see us? Kaltenegger and her collaborators used new data from the European Space Agency’s Gaia mission to figure out which stars have, have had, or will in the next 5,000 years have the right…

The Earth from space. This image elements furnished by NASA.

Cornell: Earth Could Be Seen by ET Far More Easily Than Thought

Using analytic software, researchers can determine whether Earth would be visible from a given star system

According to Cornell and American Museum of Natural History researchers, “Scientists have identified 2,034 nearby star-systems — within the small cosmic distance of 326 light-years — that could find Earth merely by watching our pale blue dot cross our sun”: Scientists at Cornell University and the American Museum of Natural History have identified 2,034 nearby star-systems — within the small cosmic distance of 326 light-years — that could find Earth merely by watching our pale blue dot cross our sun. That’s 1,715 star-systems that could have spotted Earth since human civilization blossomed about 5,000 years ago, and 319 more star-systems that will be added over the next 5,000 years. Exoplanets around these nearby stars have a cosmic front-row seat to…

Illustration of an extraterrestrial wearing a spacesuit standing on a mountaintop looking at the blue sky on an alien planet.

Astronomer Bets a Cup of Coffee That We’ll Encounter ET by 2036

Seth Shostak points to the increase in the number of exoplanets identified and the increase in computing power

Seth Shostak, iconic astronomer who directs the Search for Extraterrestrial Intelligence (SETI), is so confident that the vast increase in computing power, based on Moore’s Law, will make the difference in detecting signals from alien civilizations that he will bet you a cup of Starbucks coffee that we make contact by 2036. Moore’s Law (1965) originally held that computers would double in power every two years. But today’s pace is actually faster than that. And on the horizon is quantum computing and carbon computing, which would speed things up while reducing energy consumption. So Shostak (pictured) is looking at considerable reinforcements for a systematic search. He stresses that the search for ET is now largely computerized: “We don’t sit in…

weird ice planet

We Won’t Find ET on Ocean Planets, Researchers Say

We will see few extraterrestrials if a great many promising exoplanets are Waterworlds

Science writer Matt Williams has been writing a series on the question of why, despite the size of our galaxy, we see no other intelligent life forms. It could be, he suggests, that “many planets out there are just too watery!” Williams points out that, although water covers 71% of Earth’s surface, it is only 0.02% of the planet’s mass. If the proportion were much higher, Earth would be an ocean planet because the water would surface. It’s an open question whether an ocean planet would feature highly technologically developed intelligent life forms. Dolphins, for example, are quite intelligent but they do not seek to use any technology. The question of whether a planet could have too much water arose,…