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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.



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:

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.


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…)

Tour of the Telescope

Yesterday, we had a chance to see the telescope in all of its glory. And it is HUGE!

The Gemini South Telescope with the dome lights on.

The Gemini South Telescope with the dome lights on.

It really makes you appreciate the amount of equipment you need to directly image these faint extrasolar planets that are orbiting other stars. Andrew, the telescope operator, then pointed the telescope down so that we could get some nice photographs with the 8-meter mirror. Here’s my telescope selfie:


Telescope selfie!

Telescope selfie!

The 8 meter mirror is so big it’s hard to fit into one single shot. This was the best I could do. Although some others are a bit more serious about their photography…

Markus sprawling out to get a nice shot of Lee, a journalist visiting us, and the telescope mirror.

Markus sprawling out to get a nice shot of Lee, a journalist visiting us, with the telescope.

Before the sun fully set, I ran outside to grab this image of the telescope dome open.

The telescope dome open at sunset .

The telescope dome open at sunset .

Now back to observing!

Looking for signs of life on Kepler 186-F

Consider this post, which firmly states that proto-Earth Kepler 186-f has a 50% chance of harboring technologically equipped intelligent life:

Although about science, this blog is primarily lacking in real science. By my reckoning, even the most optimistic assumptions indicate a probability of << 1/1000. But that is the topic of another blog.


A few of the 42 radio dishes of he Allen Telescope Array at the time of its dedication in October 2007. Photo courtesy of the SETI Institute.

Here I’m exposing greater detail about a secret experiment conducted at the SETI Institute in March and April of 2014.


GPI 3rd Commissioning Run – Introduction

Hello GPI fans – this is my first post at Cosmic Diary. I’m a NASA Sagan postdoctoral fellow at the University of Arizona and a member of the Gemini Planet Imager science team. While I was at UC-Santa Cruz for my PhD, I worked with the PI, Bruce Macintosh, to develop MEMS deformable mirrors for GPI. These days, I spend a lot of time in Chile commissioning extreme AO systems, which is pretty fun! Specifically, I’m usually working on and blogging about the Magellan AO system, MagAO.

Sunset at Gemini

But this week, I’ve come down to Chile to help with GPI’s 3rd commissioning run. I’m excited to be here and to see GPI on sky!


How we know wind blows down Olympus Mons’ flanks

ESP_035663_1985_1.0xA piece of Mars: It’s similar to my last post, but I love these wind tails. This is a tiny bit of the eastern slope of the gigantic volcano, Olympus Mons. The dusty surface has been covered by boulders (the largest of which is ~20 m, or 65 ft), probably flung there from a distant meteor impact on Mars. Winds screaming from the top of the volcano (from the left) have formed wind tails in the lee of these boulders. And there are some funky little ripples on them. (ESP_035663_1985, NASA/JPL/Univ. of Arizona)

The wind giveth and the wind taketh away

ESP_035994_1805_1.0xA piece of Mars: In the center of this image is a 270 m crater (885 ft) that was nearly buried, along with the surrounding terrain, by dust. Since then, wind from the upper left has scoured the dust deposit, forming streamlined horse-tail shapes. A few meter-scale boulders, possibly flung in from nearby impacts, show the most recent streamlined erosion. (ESP_035994_1805, NASA/JPL/Univ. of Arizona)

Big ripples near Opportunity

ESP_035909_1775_0.42xA piece of Mars: This shows the location of the rover Opportunity as of late March, 2014. It’s been trolling around the rim of Endeavour crater. Just inside the crater, there are some large ripples (the biggest is ~10 m wide) that have formed from erosional scours in dark sediments on the crater interior walls. The rover won’t ever go over there, but maybe it will climb to the other side of the rim and take some nice images of them. (HiRISE ESP_035909_1775, NASA/JPL/Univ. of Arizona)

Characterizing the exoplanet HD 95086b with GPI.

Another week and yet another article based on GPI data has been accepted for publication. A team led by a European astronomer has analyzed observations of the planetary system named HD 95086, which has been known since last year for hosting an exoplanet, named HD 95086b. GPI data was extremely useful in confirming that the planet is co-moving with its star and in constraining its properties, such as its temperature and composition.


Final images of the HD 95086 system at H (top) and K1
(bottom) bands from two different data analysis pipelines. The planet (arrow)
is detected in all images.