Profile cover photo
Profile photo
SETI Institute
7,569,186 followers -
Our mission is to explore, understand and explain the origin, nature and prevalence of life in the universe.
Our mission is to explore, understand and explain the origin, nature and prevalence of life in the universe.

7,569,186 followers
About
SETI Institute's posts

Post has attachment
On February 23, 2017, the SETI Institute went "Facebook Live" to talk about the newly identified exoplanets named TRAPPIST-1 with SETI Institute researchers Seth Shostak, Franck Marchis, and Susan Thompson, and our CEO Bill Diamond. This is the first time scientists have discovered so many terrestrial planets orbiting a single star – this could be the best target in the galaxy to search for extraterrestrial life. See and hear what our scientists think about this discovery and what is coming next. Watch here: http://buff.ly/2lCZZEf

Post has attachment
Searching for Life on 7 Nearby Alien Worlds: How Scientists Will Do It

The team continues to study the TRAPPIST-1 system with Hubble. But such work can characterize atmospheres only in a relatively broad sense; the hunt for possible signatures of life such as oxygen and methane will require new instruments, the researchers said.

Luckily, such gear will be online soon. NASA's $8.8 billion James Webb Space Telescope (JWST) is scheduled to launch in late 2018, and three huge ground-based instruments — the European Extremely Large Telescope (E-ELT), the Giant Magellan Telescope (GMT) and the Thirty Meter Telescope (TMT) — should start observing the heavens by the early to mid-2020s.

Indeed, the TRAPPIST-1 system will likely be one of the first targets for JWST once the telescope is operational, Nikole Lewis, an astronomer at the Space Telescope Science Institute in Baltimore and co-leader of the 2016 Hubble study, said during a press briefing today. JWST's observations should allow astronomers to get a good handle on the TRAPPIST-1 planets' atmospheres by the early 2020s, Lewis added.

JWST, E-ELT, GMT and TMT will all be capable of sniffing out "biosignature" gases, their builders have said. (The big ground-based scopes will also be able to image a number of exoplanets directly, but the TRAPPIST-1 worlds aren't good candidates for such photography because they're so close to their parent star, study team members said.)

Read more: http://buff.ly/2lCWhud

Post has attachment
NASA’s New Horizons, IAU Set Pluto Naming Themes

In early 2015, the SETI Institute hosted the “OurPluto” naming campaign, which was endorsed by NASA and the International Astronomical Union (IAU). The goal was to prepare a list of potential categories and names for the surface features on Pluto and its large moon Charon. At the time, New Horizons was speeding toward the Pluto system, preparing for its July encounter.

This week, the IAU accepted the naming themes that were developed as a part of the public campaign. This clears the way for the IAU to begin formalizing the names that were proposed by the public through the OurPluto web site.

“We have been delighted to be able to share the excitement of the New Horizons mission with people from all over the world,” said Mark Showalter, a senior research scientist at the SETI Institute and the New Horizons team member who organized the “Our Pluto” naming campaign. “I look forward to seeing many of the public’s thoughtful suggestions officially assigned to the maps of Pluto and its moons.”

Read more: http://buff.ly/2mjc8fK

Post has attachment
A Planet Soon to Meet Its Demise

The Kilogree Extremely Little Telescope (KELT) consists of two telescopes — one in Arizona and one in South Africa — that each have a 4.2-centimeter aperture. In total, KELT observes roughly 70% of the entire sky searching for planets transiting bright hosts. And it’s recently found quite an interesting one: KELT-16b. In a publication led by Thomas Oberst (Westminster College in Pennsylvania), a team of scientists presents their find.

KELT-16b is what’s known as a hot Jupiter. Using the KELT data and follow-up observations of 19 transits, Oberst and collaborators estimate KELT-16b’s radius at roughly 1.4 times that of Jupiter and its mass at 2.75 times Jupiter’s. Its equilibrium temperature is a scalding 2453 K — caused by the fact that it orbits so close to its host star that it completes each orbit in a mere 0.97 days!

This short period is extremely unusual: there are only five other known transiting exoplanets with periods shorter than a day. KELT-16b is orbiting very close to its host, making it subject to extreme irradiation and strong tidal forces.

Based on KELT-16b’s orbit, Oberst and collaborators estimate that the planet began a runaway inspiral by the age of 1 billion years. Now, at ~3.1 billion years old, KELT-16b is orbiting at a radius of just over 3 stellar radii above its host’s surface. The authors estimate that KELT-16b’s continuing inward spiral could end in the planet’s destruction by tidal forces in as little as another 550,000 years.

Read more: http://buff.ly/2lxUrLk

Post has attachment
Layers and Dark Dunes

Much of Mars' surface is covered by fine-grained materials that hide the bedrock, but elsewhere, such as in this scene, the bedrock is well exposed (except where covered by sand dunes).

Colors are enhanced in the cutout of a pit exposing reddish layers.

The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 26.7 centimeters (10.5 inches) per pixel (with 1 x 1 binning); objects on the order of 80 centimeters (31.5 inches) across are resolved.] North is up.

Image credit: NASA/JPL-Caltech/Univ. of Arizona

Larger image: http://buff.ly/2lBJRBp
Photo

Post has attachment
Winston Churchill and E.T

The context of his ruminations was shaped by the work of astronomer Edwin Hubble and others, who had just shown that the universe was far larger than previously believed. There were not only hundreds of billions of stars populating the galaxy, but vast numbers of other galaxies.

But were there also planets, the presumed habitats for life? In Churchill’s time, the received wisdom on planet formation was the 1905 Chamberlin-Moulton theory. It postulated that solar systems were the result of close interactions between two stars. Since stars seldom get close to one another, this theory implied that planets would be extraordinarily rare.

This might have dissuaded a lesser thinker from believing that the heavens could have many cool worlds on which to host biology. But Churchill had a daring mind, and considered that the Chamberlin-Moulton idea might be wrong (and in fact, it is). He then proceeded to argue in a stunningly modern way that the number of planets spangling the heavens could be almost inconceivably large, and that modesty alone would suggest that Earth is not the only place where intelligent life might exist.

Read more: http://buff.ly/2lwsUdg

Post has attachment
REMINDER: Join us today, Thursday 23 February at 3 pm PST, as scientists from the SETI Institute participate in our first ever Facebook Live event! We will broadcast a short discussion between astronomers Seth Shostak, Franck Marchis, and Susan Thompson. They will be talking about today’s NASA announcement that seven potentially habitable planets have been discovered in orbit around red dwarf star TRAPPIST-1. Visit our FB page here: http://buff.ly/2lt6MQL

Image credit: Franck Marchis & Helene Marchis
Photo

Post has attachment
A Solar System Found Crowded With Seven Earth-Sized Exoplanets

Seven planets orbiting one star. All of them roughly the size of Earth. A record three in what is considered the habitable zone, the distance from the host star where liquid water could exist on the surface. The system a mere 40 light-years away.

The latest impressive additions to the world of exoplanets orbit the dwarf star known as TRAPPIST-1, named after a European Southern Observatory telescope in Chile.

Previously a team of astronomers based in Belgium discovered three planets around this dim star, but now that number has increased to include the largest number of Earth-sized planets found to date, as well as the largest number in one solar system in the habitable zone.

This is a very different kind of sun-and-exoplanet system than has generally been studied. The broad quest for an Earth-sized planet in a habitable zone has focused on stars of the size and power of our sun. But this one is 8 percent the mass of our sun — not that much larger than Jupiter — and with a luminosity (or energy) but 0.05 percent of that put out by our sun.

Read more: http://buff.ly/2lNY14M

Post has attachment
ICYMI: This weird planetary system seems like something from science fiction (by Seth Shostak)

...Meanwhile, we can do at least one experiment: Examine this system for radio signals that would indicate the presence of intelligence. And indeed, the SETI Institute used its Allen Telescope Array last year to observe the environs of TRAPPIST-1, scanning through 10 billion radio channels in search of signals. No transmissions were detected, although new observations are in the offing.

How sensitive was this search? Assuming that the putative inhabitants of this solar system can use a transmitting antenna as large as the 500-meter FAST radio telescope in China to beam their messages our way, then the Allen Array could have found a signal if the aliens use a transmitter with 100 kilowatts of power or more. This is only about 10 times as energetic as the radar down at your local airport.

And whether or not TRAPPIST-1 has inhabitants, its discovery has underlined the growing conviction that the universe is replete with real estate on which biology could both arise and flourish. If you still think the rest of the universe is sterile, you are surely singular, and probably wrong.

Read more:

Post has attachment
Light curves of the seven TRAPPIST-1 planets as they transit

This diagram shows how the light of the dim red ultra cool dwarf star TRAPPIST-1 fades as each of its seven known planets passes in front of it and blocks some of its light. The larger planets create deeper dips and the more distance ones have longer lasting transits as they are orbiting more slowly. These data were obtained from observations made with the NASA Spitzer Space Telescope.

Credit: ESO/M. Gillon et al.

Larger image: http://buff.ly/2lIw7Xv
Photo
Wait while more posts are being loaded