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Des mondes similaires au nôtre cachés dans des centaines d’exoplanètes ? SETI PR en Francais

Communiqué de presse de l’Institut SETI et de CASCA
Monday, June 09 2014 – 12:15pm, PDT

Mountain View, CA -
Cette année a été intense pour les chasseurs d’exoplanètes, ces planètes autour d’autres étoiles. Une équipe d’astronomes de l’Institut SETI et du centre de recherche de la NASA Ames a découvert 715 nouvelles exoplanètes enfouies dans les données du télescope spatial Kepler. Ces nouveaux mondes qui tournent autour de 305 étoiles différentes, constituent des systèmes planétaires multiples, similaires a notre système solaire, lui-même constitué de huit planètes. L’annonce de cette découverte a été suivie par une nouvelle encore plus importante dans le monde de l’astronomie : la même équipe a annoncé la découverte de Kepler 186f, une planète de la même taille que la Terre qui tourne autour de son étoile dans la zone dite habitable. Cette decouverte constitue une étape essentielle vers la détermination de l’existence de planètes de type Terre dans la Voie Lactée.

Une vue artistique décrivant les systèmes planétaires découverts par le télescope spatial Kepler. Crédit: NASA

Une vue artistique décrivant les systèmes planétaires découverts par le télescope spatial Kepler. Crédit: NASA

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The always-changing landscape

ESP_035558_1830_0.831xA piece of Mars: Over time, windblown sand can wear down a surface. This isn’t so common on Earth, where water, ice, and life are more likely to change the landscape, but it’s typical of many places on Mars. Here, we see one moment in time, where neverending sand (blowing from bottom right to top left) creates a pattern on the surface and scours a hole around a resistant rock. (ESP_035558_1830, NASA/JPL/Univ. of Arizona)

First Observing Run

I recently returned from the third commissioning run for the Gemini Planet Imager. Up until now, I had never been observing. I had never even seen the Milky Way. And as far as firsts go, I hit the jackpot — my first observing run at Gemini South, commissioning GPI.

Pointing to Gemini

Up on the mountain for 6 days, sunset to sunrise we busily work to gather light from the sky into GPI. But everyone takes a few moments during the night to step outside and look at the sky with their own eyes — no one misses the opportunity.

I’ve always lived in a city where only a handful of stars are visible at best. While I was always fascinated with the universe (especially thanks to fantastic Hubble press releases) I guess astronomy never felt that accessible to an urbanite like me, for whatever reason. By some stroke of luck, this May I found myself surrounded by mountains and stars, sitting in the control room of a massive telescope filled with technologically impressive instruments and equally impressive brains grasping for answers from the sky. I am definitely fulfilling a childhood dream.

While taking data in the control room, the tone is mostly quiet concentration and focus. But when we get to see the 8-meter move, everyone watches in excitement and awe. Luckily, I hit record.

This has been one of the most interesting and exciting trips I’ve taken. I have an added appreciation for the Gemini Planet Imager and its operation after being on the front line. GPI is not only a platform for great science but an amazing resource and opportunity for the students that are part the commissioning workforce.

Flow

ESP_031944_1790_0.38xA piece of Mars: This is a bit of the flank of Arsia Mons, one of Mars’ great volcanoes. The big changes in topography are ancient relics of erosion by lava and great tectonic pulling. What I like is that the scene (1.58×1.18 km, or 0.98×0.74 mi) is covered in bright dust (looks a bit like snow here, doesn’t it?). And that dust has been eroded by wind channeled through the topography. So here we see signs of flow, both from ancient lava and from more recent wind. (HiRISE ESP_031944_1790, NASA/JPL/Univ. of Arizona)

54 years of space exploration: an updated map that you must see

National Geographic asked 5W Infographics to update its 50 Years of Exploration graphic, a classic that I use often in my talks to illustrate our space exploration program and its focus on the inner part of the solar system.

The updated version, renamed “Cosmic Journey“, is spectacular, better organized and easier to follow than its predecessor. It has been updated to include new missions sent over the past 4 years. The new color code includes the paths of failed, as well as successful, missions and also the nation that led them.

Cosmic Journey by Sean McNaughton, Samuel Velasco, 5W Infographics, Matthew Twombly and Jane Vessels, NGM staff, Amanda Hobbs. Source: NASA, Chris Gamble.

Cosmic Journey by Sean McNaughton, Samuel Velasco, 5W Infographics, Matthew Twombly and Jane Vessels, NGM staff, Amanda Hobbs.

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Debunking Hoagland’s “Glass Worms” with HiRISE

ESP_035634_2160_1.0xA piece of Mars: Several years ago, a guy named Richard Hoagland claimed that some parallel linear features on Mars looked like the ridges of a transparent earthworm, calling these things “glass worms”. Phil Plait debunked it nicely, but Hoagland stood his ground. He hasn’t said much about them lately, has he? Here’s why. New images show that, as scientists originally thought, these are nothing more than windblown ripples in the floors of channels, just like the many thousands of ripples seen all over Mars. Go science! (HiRISE ESP_035634_2160, NASA/JPL/Univ. of Arizona)

SETI – Your Opinion Doesn’t Matter: part 3

This is part 3 and final installment in the Your Opinion Doesn’t Matter blog. Please read parts 1 and 2 for context.

In part 2 I divided spurious opinions regarding topics in SETI into 3 categories: science-free, anti-scientific, and convicted statements of the “self evident.” Here we exemplify the last category.

Convicted Opinions that are not so Self-Evident

Steven Hawking is the epitome of scientific hero. He overcame dramatic life challenges to become a peerless leader in the progress of general relativity theory of gravity and quantum mechanics. When it comes to theoretical gravitation, I’m not fit to tie his bootlaces. But he isn’t God. (I hear the jingling of sharpened spoons outside my window.) As far as I know! Speaking of intelligent life elsewhere, he said[4], “To my mathematical brain, the numbers alone make thinking about aliens perfectly rational.” This quote appears only because it supports my own point of view, ha ha! I’m about to say that Hawking isn’t the best source for information about ET.

Unlike many people, Hawking has an imagination: “I imagine they [aliens] might exist in massive ships, … become nomads, looking to conquer and colonise whatever planets they can reach.” Whoa! Where did that come from? Possibly… from a science fiction movie?  Proof that Steven Hawking is really a college undergraduate at heart.  (jingle…) Ahem, that was just my little joke, Mr. Dr. Professor Hawking. Sir.

It is plausible that Hawking’s comment inspired this excellent book[5], penned by scientists** who really are expert*** in SETI issues. For the greater part, experts suggest that aliens are more likely to be altruistic — willing to help us out with no expectation of immediate reward — than predatory. For example, members of a predatory species that have conquered their planet will have only each other to prey upon. This is a state of unstable equilibrium. So they had better lose their predatory instincts fast, or annihilation is inevitable in the long run. Hence, the aliens are not likely to be purely predatory.

**By sheer coincidence, this book is edited by none other than Doug Vakoch, the Director for Interstellar Message Construction at the SETI Institute, with an office a few doors down from mine.

*** At least, as expert as anyone could be.

So, what do you think? It doesn’t matter! “Do aliens exist?” is a question that will someday be answered by science. Provided we don’t give up on the search for them.

[4] http://www.telegraph.co.uk/science/space/7631252/Stephen-Hawking-alien-life-is-out-there-scientist-warns.html

[5] http://www.amazon.com/Extraterrestrial-Altruism-Evolution-Frontiers-Collection/dp/3642377491

SETI – Your Opinion Doesn’t Matter: part 2

This blog extends part 1 of a blog with the same title, and is followed by part 3.

Albeit imperfect, the radio search for extraterrestrial intelligence (SETI) tests a scientific question (hypothesis), “Did intelligent life get started anywhere else in the universe?” This a scientific question (not a matter of opinion), because it has a definitive answer (yes or no) that can be tested by observing nature (i.e. with our telescope). “Is there a God?” also has a definitive answer, but it is not scientific because we have no hope that observations of nature can answer this question. The God question falls into the realm of “opinion” (sound of jingling spoons) because it can be answered only by methods outside the scientific framework. (Crickets…, OK, that’s better!)

Malformed opinions about SETI topics can be broken down into 3 types : (1) science-free, (2) conflicting with science, and (3) strongly convicted statements of the “self evident” which aren’t, really.

Ignorance is bliss (science-free) Opinions

A very readable book (meaning that I could read it all the way through), “The Elusive Wow: Searching for Extraterrestrial Intelligence,” by Robert H. Gray discusses the “WoW!” signal, observed at Ohio State University in 1977. I am critical of “WoW!” because the signal did not even pass the candidate tests in the original experiment, so why should we believe it based on arguments made after the fact? A review on Amazon [2] speaks differently. It discredits Gray’s book with the argument that, signals from far away are very weak. Wow! That’s convincing. Especially compared with actual science showing that an Arecibo-like transmissions from nearby stars can be detected, right now, by us, if we look hard enough.

Anti-scientific Opinions (conflicting with science)

A certain blog [3] states that there are even (50-50) chances of finding intelligent life around the recently-discovered exoplanet Kepler 186-f. Remember, Kepler 186-f is a “goldilocks” planet orbiting a star 500 light-years from ours. 186-f is almost the same size as Earth, presumably a rocky planet and in a “hot” (that is, not hot) orbit around its star to keep the temperature just right (that is, possibly close to a temperature) where (microbial) life (as we know it) can flourish (that is, be not immediately destroyed). And then the life must be intelligent like us and be actively transmitting in our direction. 50-50 chance, huh?

In round numbers, all targeted SETI searches until now show that fewer than 1/1000 “likely” stars harbor planets that are intentionally beaming signals toward us.* We think 1/1000 is still a pretty big number compared to something like 100000000000 planets just in our galaxy. Even better, exoplanets discovered by the Kepler telescope and other probes show that most stars have planets, and somewhere around 1/5 of stars host “habitable” planets that are favorable for the evolution of life. Promising indeed. Even so, these probabilities don’t add up to a 50-50 chance of finding intelligence.

*Are you surprised that 50 years of SETI research can say no more than that? This actually shows how little effort (money) has been expended over the years to do SETI. Not for lack of scientific interest, but simply because scientists have to eat. Write your congressional representatives and urge them to support funding for SETI research.

If anyone wants to place a bet, we have insider information on Kepler 186-f, thanks to first author Elisa Quintana, a scientist at the SETI Institute. In the few weeks between submission of the paper and announcement of the discovery of 186-f, the SETI Institute pointed its telescope ATA at Kepler 186-f as much as possible (>8 hours / day) looking for technology-generated signals between 1-9 GHz. Sadly, our observations did not discover any evidence for artificial signals from that direction. So far.

This blog is continued in part 3.

[2] http://www.amazon.com/review/R13G7YIOCUL0WN

[3] http://www.science20.com/quantum_gravity/blog/a_better_than_5050_chance_kepler186f_has_technological_life-134555

SETI – Your Opinion Doesn’t Matter: part 1

Ha ha! The title should garner angry crowds bearing sharpened spoons*, chanting before my office window in Mountain View.

*Because spoons are the only tools their caretakers will allow.

Not so seriously, a hilarious article in the tabloid, Daily Mail, is illustrative, and reminds me of the famous “heavy boots[1]” questionnaire:

http://www.dailymail.co.uk/sciencetech/article-2622311/Were-not-ready-meet-aliens-Humans-stupid-religious-cope-extra-terrestrial-life-claims-expert.html.

Even the link is funny! An apparently reputable journal recently published results of interviews with 116 college undergraduates describing their scientific “opinions” about SETI (search for extraterrestrial intelligence). We leave aside the societal relevance of opinions from 18-23 year olds who’ve never worked a day in their life! (Uh oh, I hear jingling spoons again.) Ha ha, just kidding, all you large, young, and physically intimidating people attending their first years of college!  The crucial results:

(a) 82.1% think it is important to have a space agency.

(b) 71.4% think the military should have the main role in the event of contact with an alien civilisation.

(c) 80% believe if we find aliens more advanced than us they will try to conquer us.

(d) 78% believe there is a chance we’ve been visited by aliens in the past.

From (d) we infer that most undergraduates received their foundational science education from science fiction movies. This helps explain the rest. I’m most worried about question (b). Should the military be the first of “diplomats” that aliens meet?  The army has a hammer, called war. What better way to start a war than by throwing spitballs at aliens?

Actual posted comments to the article:
” When the Old Ones, who dwell among the stars return, they will put us in our place.”

“It would destroy religion and the oil industry.”

Fan favorite:

” The Vatican is at this very moment expecting to meet an alien to save the world. This will be the seed of Satan!”

The point I’m making is that SETI is a branch of science. The opposite of “science,” for want of a better word, might be called “belief.” (jingle, jingle…) Example: Recently at the ATA (visitor hours 9am-3pm M-F), a courageous young man told me straight to my face, “I don’t believe in aliens.” What was I to do? I said, “Well, it’s not a religion.” (jingle, jingle…) Ah! Not to disparage religion or any other system of beliefs.  To avoid the imminent mobs, I’ll re-label what I called “beliefs” as, “convicted opinions that cannot be tested by observations of nature,” or opinions for short.

Whether or not aliens exist is not a matter of anyone’s opinion. It is a scientific question that can and should be answered with science.

For more see parts 2 and 3 on this blog topic.

[1] http://blog.sciencegeekgirl.com/2009/11/09/myth-because-the-astronauts-had-heavy-boots/

GPI 3rd commissioning run — Astrometric calibration with a little help from MagAO

Astrometric calibration is critical for GPI: When we see a faint dot near a star, the best way to check whether it is a planet orbiting that star, versus whether it is a background star along the same line-of-sight, is to compare the astrometry at a later date. Astrometry means measuring the stars — measuring the exact position in arcseconds and angle from North. But to figure out the size of our pixels on the sky, and the orientation of our camera and which way is North, we have to observe known groups of stars and measure their separations and angles. Then we compare our measurements to those from other instruments and tie that back to basic calibrations done in the lab with pinhole masks to create a common reference frame. This is how we calibrate astrometry.

A handful of faint stars clustered around a bright guide star makes for an excellent astrometric calibration field. These are images of the same field with MagAO/VisAO in z’, MagAO/Clio in H-band, and GPI in H-band. VisAO images courtesy Jared Males, Clio images courtesy KM, and GPI images courtesy Jason Wang.

But the field of view of GPI is very small, and it is hard to find a group of stars that are very close together, that also have a bright enough guide star for the AO system. (more…)