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NASA Tweetup Here I Come
I still remember the moment I found out I was selected to attend the GRAIL launch NASA Tweetup. While driving home from the annual meeting of the Astronomical Society of the Pacific, I found myself getting a little tired so I decided to stop off and grab a shot of sugar via a strawberry milkshake. As I sipped down my pink goo, I passed the time by reading my latest emails. That’s when I first saw the email inviting me to the Kennedy Space Center to participate in a NASA Tweetup! Naturally, my response was to tweet the news.
NASA Tweetups are outreach events in which the space agency invites selected twitter users to attend special events such as shuttle launches and festivities. The upcoming tweetup will be held the 25th hosted by NASA. To be selected all you need is an active twitter account and the ability to attend the scheduled events. If you satisfy these simple criteria, you can throw your name into a hat and hope it’s randomly picked. For the GRAIL tweetup there were over 825 entries, 150 of which were selected for attendance.
During a typical tweetup participants are given behind the scenes tours of facilities, in addition to formal and informal talks by mission scientists, engineers, and NASA officials. Some tweetups are as short as a few hours, while the longest last for a week in the case of the STS 133 shuttle launch tweetup.
Before a few days ago I couldn’t comment too much as to what the GRAIL tweetup would entail, mostly because the details hadn’t yet been finalized. Then, last Thursday we got our orders. The planned list of activities looks absolutely awesome. Before, I was excited just to be invited, now I’m absolutely ecstatic.
The GRAIL NASA Tweetup is a two day event. It starts first thing Wednesday morning (Sep 7) with tours of Kennedy Space Center and Cape Canaveral Air Force Station. After lunch we’ll be treated to talks by:
- Jim Adams — deputy director, Planetary Division, Science Mission Directorate
- Charles Bolden — NASA Administrator
- Sami Asmar — GRAIL deputy project scientist, NASA’s Jet Propulsion Laboratory
- Maria Zuber — GRAIL principal investigator
- Neil de Grasse Tyson — Frederick P. Rose director at the Hayden Planetarium at the American Museum of Natural History
Besides the above speakers, there will be representatives from Sally Ride Science, United Launch Alliance, and Lockheed Martin.
And that’s just the first day, pre-launch activities. Day 2 starts with a trip to the causeway for viewing of the Delta II rocket launch that will carry the twin GRAIL satellites into space. After a successful launch (al fingers crossed here) we’ll head to the Kennedy Space Center Visitor Complex for talks by Apollo 16 astronaut Charlie Duke, Neil deGrasse Tyson, and Nichelle Nichols (Lt Uhura from the original Star Trek series).
That’s it for the official GRAIL launch NASA Tweetup. However, that’s not the end of the fun. The second day will only be considered complete after the tweetup tradition of the Endless BBQ held at the Cocoa Beach Brewing Company.
Carl Sagan’s Cosmos gets a Reboot with Surprise Players Involved
When Carl Sagan’s miniseries Cosmos: A Personal Voyage first aired in 1980 I was only three years old. Even though it has been replayed a number of times since then, I’ve admittedly not seen it. Unlike most of my colleagues who often site Carl Sagan as inspiration—and try to imitate his iconic mannerisms—I cannot say this show influenced my love of astronomy. What’s worst, I think (I’m not even positive) that I may have a copy of the thirteen part PBS miniseries sitting on a shelf in my office. I’m so ashamed.
I haven’t prioritized watching the Cosmos series because I know personally how fast astronomy changes. In the thirty plus years since the original airing, our views of the Universe have changed drastically. My (unfounded) expectations are that the outdated Cosmos episodes wouldn’t capture my CGI-needed imagination.
Luckily that will all change soon enough. Recently Fox Broadcasting Company (yes, that Fox) has announced that it will be remaking Cosmos. The updated version, which will be called Cosmos: A Space-Time Odyssey, will in 2013.
As of right now, the show will air on Fox in a primetime slot. This is interesting in of itself. The original Cosmos aired on PBS which has a certain self-selected audience. Fox has its own audience and it’s one that I wouldn’t personally equate to PBS. So there is a possible concern here that maybe Fox will butcher a classic to align with its brand of entertainment.
However, there is some saving grace here. First off, two of the original three responsible for Sagan’s version of Cosmos will be involved in the production of the updated version (his widow and writer Ann Druyan, and astrophysicist Steven Soter). Second, although Sagan is not replaceable, Fox has gotten the next best option in Neil deGrasse Tyson to be the new host. In fact, it was from Tyson himself that I first heard this news when he recently announced it at the annual meeting of the Astronomical Society of the Pacific. Currently Tyson is the host of the largely successful NOVA scienceNOW show on PBS in addition to writing popular books and being the Frederick P. Rose Director of the Hayden Planetarium in New York City.
Now for the last twist in this story. One of the executive producers of the new series is Seth MacFarlane, the creator of Fox shows Family Guy, American Dad, and The Cleveland Show. As someone that watches each of these shows, and I follow MacFarlane on twitter, I can say that he does occasionally sneak in some great science geek jokes. In reading about the recent news for the Cosmos remake (see here and here for example) I’ve come to also realize that MacFarlane is a fan of science and he’s concerned about the direction the US is heading in. In fact, it was MacFarlane’s doing that got the new version on Fox where it will get primetime exposure and will hopefully hit an audience that traditional science shows miss.
My First Amaz!ng Meeting – Day 1
The 2011 edition of the The Amaz!ng Meeting, TAM 9 from Outer Space, represented my first foray into a skepticism meeting. Having heard so much about TAM through podcasts, twitter, and the blogosphere I thought it was time to experience TAM for myself. In a prior blog post, My First Amaz!ng Meeting – Prologue, I described the general idea of TAM and the workshops leading into the meat of the meeting. Now for my retelling of day 1.
[Side note: I apologize for the length of this post. This was my favorite day at TAM 9 and a lot of what happened on this day I found so cool.]
Having flown in from the east coast the day before it wasn’t too hard to wake up for the 8:00 am live recording of the Skeptics Guide to the Universe (SGU) podcast. Admittedly I’ve never listened to SGU before. My podcast time is usually taken up with Skepticality, Monster Talk, and Skeptoid. I may have been the only person in the audience that hadn’t listen to SGU. They seem to have a cult following and now I see why. Even without a frame of reference to know what the usual SGU format is, I still found the podcast interesting and even a bit funny. I’m going to have to find time to listen to SGU.
Following the SGU recording, the first in a parade of invited speakers took the stage. Being my first TAM I was admittedly star struck to see the likes of James Randi and Michael Shermer right out of the gate. Throughout TAM my admiration for Randi grew. Not only has he dedicated his life to spreading skepticism, he has the absolute greatest, most welcoming personality. Unfortunately I was not able to talk with Randi personally, but I continually heard conversations about those lucky ones that were able to get a hug from him. It seems James Randi is big on hugs, which he repeatedly professed throughout the meeting.
After Michael Shermer spoke about his new book The Believing Brain: From Ghosts and Gods to Politics and Conspiracies
Next was Eugenie Scott, the Executive Director of the National Center for Science Education (NCSE). I’ve had the pleasure of hearing Dr Scott speak before on the NCSE’s original focus of combating the Intelligent Design’s movement to include creationism in school curricula. This time Dr Scott’s talk illustrated the parallels between Intelligent Design proponents and Anthropomorphic Global Warming deniers. It’s amazing to see how loud, but poorly supported rhetoric can be effective in persuading individuals to believe garbage. The most important outcome of Dr Scott’s talk is that the NCSE is now going to expand its already effective anti-Intelligent Design efforts to now include producing resources for addressing global warming deniers.
Immediately following Eugenie Scott was astronomer Lawrence Krauss. Dr Krauss’ talk was exclusively on one of my favorite physicists, Richard Feynman. I find Feynman fascinating for a number of reasons, including his seemingly superhuman intelligence coupled with his fun loving appreciation of life. Dr Krauss’ talk covered a number of stories from Feynman’s early years, one of which has now become my favorite Feynman tale: Early in Feynman’s career he found the love of his life, Arline Greenbaum. Despite knowing that his eventual wife was going to die of tuberculosis, Feynman married Arline all the same. Sadly she did die at a young age with Feynman at her side. At the time of her death Feynman notice that the clock in her hospital room had stopped. For many this would have been a sign of divine intervention, but to Feynman there was a simple, natural explanation. Despite watching his love die before him, through the grief he figured out the clock probably stopped because the nurse accidentally stopped the clock when she recorded the time of death.
Heading into lunch magician Jamy Ian Swiss interviewed James “The Amazing” Randi along with Steve Shaw (Banachek) and Michael Edwards on their involvement in the infamous Project Alpha. I cannot do the Project Alpha justice here so instead I’ll direct you to Wikipedia entry. Although I had heard the story before, it was still entertaining to hear directly from the participants. If there’s ever a case study in the proper use of ethics in a skeptical investigation, Project Alpha is it.
During the afternoon session, biologist, and author of the Pharyngula blog, PZ Myers spoke on A Skeptical Look at Aliens. Being an astronomer and Dr Meyers a biologist, I had never had the opportunity to hear him speak in person before. Although his topic covered some technical aspects of what we might expect out of how an alien life form may look, PZ’s eloquent presentation and simple explanation made his talk completely accessible. I’ve always respected PZ’s willingness to speak out against bad information and bad arguments on the sensitive topic of religion, but from one scientist watching another, I now have a new admiration for his professional work as well. (To be clear, Dr Myers’ credentials stand on their own, but witnessing him in person really put his talents into perspective.)
Following PZ was astronomer Pamela Gay. Dr Gay’s talk summarized our sad current state of space science. She noted how inspirational NASA has been and how the allure of space is so accessible and enticing to young kids. Yet as our government continually tightens its fiscal belts, it has repeatedly reduced funding for space exploration and science education. During this emotional speech she spoke about our country’s youth and how we were failing them, taking away their scientific aspirations. In the end, this was one of my favorite TAM talks.
Sticking with the space theme, following Dr Gay’s speech was a panel discussion on Our Future in Space. The panelist included Bill Nye “The Science Guy”, Neil deGrasse Tyson, Pamela Gay, and Lawrence Krauss. The panel discussion was moderated by astronomer Phil Plait of the Bad Astronomy fame. To state it simply, this panel discussion fracas was pure entertainment. Between some very valid points about the financial cost, what has driven space exploration in the past, and the expected science returns of space exploration, was entertaining banter between the panelist. The coup de grâce of the discussion was when Dr Gay shushed Dr Tyson so she could speak. It was obvious that there was much mutual respect amongst the panelist but it was just as obvious that they truly have differing viewpoints on our future in space exploration. Although the panel consisted of only four individuals, their disagreement is reflective of the astronomy community as a whole. There really isn’t a clear consensus of what we should do, with the exception that all astronomers are in agreement that all of science is not receiving the appropriate financial government support.
The final talk of the day was the keynote address by Neil deGrasse Tyson. This was the third time I’ve heard him speak and some of the material was repetitive to earlier talks, but regardless, I was informed and entertained. The central theme of Dr Tyson’s talk was America’s drifting away from being a superpower in science innovation. Although we were the first country to put a person on the Moon, we have slipped away and allowed such nonsense as not labeling the thirteenth floor of skyscrapers, bad news reporting, and not recognizing scientists as public figures like other countries do. Most telling from Dr Tyson’s talk was a pair of maps that displayed the scientific output from all the countries. While the United States does produce a substantial amount of scientific findings, if you look at the change in output over the last ten years, countries like Japan and China are sky rocketing to the lead of scientific results. The finale of the keynote address was a reminder of how cosmically insignificant humans are, yet we have the ability to learn so much about the Universe, but only if we try.
Epilogue for Day 1
I would feel remorse if I didn’t mentioned Penn Jillette’s Rock & Roll, Doughnut and Bacon Party. Yes you read that right. Penn Jillette (from Penn & Teller) hosted a party for all TAM participants. At the party Krispy Kreme doughnuts were served along side bacon. Drinks were served through a cash bar. I can now say that Corona does a nice job of washing down Krispy Kreme’s famous glazed doughnuts. For entertainment, Penn’s band No God played original and cover songs.
While I found the party entertaining it was just as fun to watch how the skeptical audience members interacted with one another. Let’s face it, there’s a selection bias in that most people that are drawn to skepticism are not former high school jocks and cheerleaders. Most skeptics were probably, to put it gently, socially awkward growing up. Me included! (The rumor amongst my former students is that I am still socially awkward.)
So that was it for day 1 of TAM 9 from Outer Space.
Check out my other reminisces about TAM 9:
My First Amaz!ng Meeting – Prologue
About eighteen months ago I started listening to the podcast Skepticality, an official podcast of Skeptic magazine. The hosts of Skepticality would often begin a podcast by promoting the upcoming annual skeptics meeting known as The Amaz!ng Meeting (TAM). At that time I had no idea how big TAM really is, so I made the mistake of not attending TAM 8. After the meeting came and went, it was clear from all the dedicated podcasts and blog posts that TAM was something special and needed to be witnessed in person, so this year I made the trek out to Las Vegas and experienced TAM for myself.
For those that haven’t been to a TAM, the meeting lasts four days and consists of a combination of workshops, talks, and activities. This year’s meeting was formally called TAM 9 from Outer Space as a homage to the classic(?) movie Plan 9 from Outer Space. Although the general theme was space, topics ranged from the paranormal to medicine and psychology to magic. The list of invited speakers was a who’s who of skepticism, which included the likes of Michael Shermer, Neil deGrasse Tyson, Eugenie Scott, Richard Wiseman, Bill Nye, and Richard Dawkins. This year’s meeting had a record attendance with over 1,600 participants, roughly half of which were experiencing TAM for the first time.
Originally I was going to write a single blog post on my personal retrospective of the meeting, then I began writing. It was quickly evident that this meeting had a large effect on me. That single post quickly grew into a monster, so I’ve decided to break apart my account into a sequence of posts each of which will represent a single day at TAM.
I will not be able to comment on everything. There simply was too much. Instead I’m going to describe what I personally found most memorable. For those speakers I don’t mention, my apologies. Every talk—and I mean this sincerely—was fascinating, but from my point of view certain talks piqued my interest more than others. For a more complete retelling of the events at TAM 9 see the live blogging at the Friendly Atheist.
TAM 9 started off with a full day of workshops. Unfortunately, because I flew in during that morning I missed the first set of workshops. From what I heard from other TAMers, the workshop on faking your own UFO pictures was interesting. Although I missed it, this workshop gave me an idea for a future Astro 101 assignment. More on that in a later post.
The first workshop I was able to attend was on Problems in Paranormal Investigation. After famed paranormal investigator Joe Nickell spoke (which was fun and interesting to hear), the guys from the Rocky Mountain Paranormal Research Society spoke on their punking of a claimed ghost detective. Their talk was not only interesting, but it led into some very interesting questions and discussions on the ethical boundaries paranormal skeptics must work within. Is it justifiable to lie, work undercover, or blatantly deceive an individual to gather pertinent information about a supposed paranormal occurrence? There’s not a simple answer to this question. Sometimes it may be worth fighting fire with fire ghosts with ghosts.
The second workshop was on Skepticism in the Classroom. While most of the discussion was not directly applicable to my own teaching, I was impressed with how effective the use of simple magic tricks could be in a physics/astronomy course as a gateway for discussing the scientific method. (The intersection of magic and skepticism was a common theme at TAM—well duh given it was hosted by the James Randi Education Foundation.) It seems I may need to learn a little magic before the start of the next semester.
Check out my other reminisces about TAM 9:
An Astrology Interview that gets Us Nowhere
It started with a brief email from a local news reporter asking if I was interested in speaking about the recent viral news for a 13th zodiac sign. Sure, why not I thought. So I immediately replied. No kidding, within 45 minutes of receiving the initial email I found myself in front of a camera, being interviewed about something I teach every semester in my Astro 101 class. (No I don’t teach astrology, but I do teach about constellations, the zodiac, and pseudoscience so naturally astrology comes up in the discussion.)
The interview went well. Lisa Edge, the news reporter, and her camera man were very polite and asked very intelligent and directed questions. I answered them to the best of abilities and tried to avoid technical jargon. After 15 minutes or so we were done. I thought things went well. So here’s what made the cut,
Okay, first off, I had no idea that they also interviewed a christian psychic. (WTF is that anyways?) I guess that’s okay because the news is suppose to be balanced. What gets me is all that great science material I gave her was lost to the editing floor. A bit of a consolation prize is that much of what she said as the story’s wrap-up is stuff we talked about.
The one question that she did ask that I wish would have survived the cut is, “Do you think this news of a 13th zodiac sign is good for astronomy?” My answer was two sided (and probably why it got cut).
On the one hand, scientists are continually trying to educate the public about what is and is not science. On a regular bases we try to demonstrate how certain studies—and I use the term loosely—act scientific but in fact are not; astrology being one of the oldest examples. For this reason, when astronomers see astrology getting face time in the media we tend to roll our eyes and think here we go again. (For some entertaining blasting of astrology check out Astrological Sign of the Times, Astrology is Still Bullshit and the Universe Doesn’t Care About You, and This is why Horoscopes are Full of Assfog.)
However, there is the flip side. Although astrology plays the roll of a child at an adult only party, there’s still a teaching moment that we as educators can seize upon. Here we have so many people listening and interested in learning about a topic closely related to astronomy and most of the professional astronomy and science educators communities are turning their backs. Instead we should take this time to educate and to demonstrate why the 13th zodiac sign is nothing new. Why astronomers have known for ages that everyones astrological sign is off because of the Earth’s precession. Why astrology is considered a pseudoscience. Ultimately this is why I did not hesitate to give the interview. While most of the science was lost in the editorial process, and I knew it would be, I still tried to get through a little bit of scientific knowledge.
For the record, I have also posted an extensive blog entry on this whole zodiac issue: The Zodiac Shuffle According to Astronomers. This entry is meant to briefly explain the science behind the 13th zodiac sign and why most everyone’s astrological sign has shifted. For another reference, check out An Astronomer Looks at Astrology by Andrew Fraknoi.
The Zodiac Shuffle According to Astronomers
Have you heard the Earth shattering news (to be read with sarcasm)? Your zodiac sign may have changed! So if you were once a Pisces, like I was, you may now be an Aquarius. To make things worst, there’s now a thirteenth astrological sign, Ophiuchus, and it’s one that nobody can figure out how to say. I can’t imagine how many relationships are now in peril, how many new found jobs will be lost, or how many missed opportunities now exist. So what are we to make of this nonsense change? Hell, why is this happening now after thousands of years of studying the stars?
The truth is, to astronomers this is old news. Very, very, very old news. Slow shifts in astrological signs and even a thirteenth zodiac member have been known for two millennia now. To understand why this is really nothing new, let’s break down all the players in the story.
We begin with a discussion on constellations. A constellation is really nothing more than arbitrary grouping of stars that lie in close proximity to each other on the sky. The stars that make up a constellation are not necessarily—and in fact rarely are—physically connected or even related to each other. For example, the stars that make up one of the most recognizable constellations Orion (shown to the right), are at all kinds of distances. The bright red star on the top left (Betelgeuse) is 429 lightyears away while the bright blue star on the bottom right (Rigel) is 777 light-years distant. If you were to travel to another nearby star in our galaxy, then Orion would look completely different. From a historical perspective, stars found their ways into constellations because ancient cultures would relate the apparent star patterns to mythological beings and tales.
The use of constellations have not been forgotten by modern astronomers. However, their purpose has change. Today constellations play the same role as borders do on Earth. Just as political boundaries are used to identify large regions of land, constellations allow astronomers to quickly describe sections of the sky. If an astronomer says they’re observing the star Beta Orionis, it’s immediately known that the object being studied is the second brightest star in the constellation of Orion (beta being the second letter in the Greek alphabet and Orionis designating the Orion constellation).
An obvious problem with this approach is that constellations are usually identified by a small number of bright stars. What about all those dim, overlooked stars that lie in-between the constellations? To resolve this problem, in 1930 the International Astronomical Union adopted the constellation boundaries suggested by noted Belgian astronomer Eugène Delporte. The constellation boundaries were chosen such that every patch of the sky falls within the jurisdiction of one and only one constellation. Today there are 88 official constellations recognized by the astronomical community. The below figure shows the constellation boundaries in the region around Orion.
During the daytime hours stars cannot be seen because the Earth’s atmosphere spreads the Sun’s incident light across the sky. (By the way, this is why the sky is blue.) If we could remove this atmospheric effect then we would observe the Sun “in” a particular constellation. The thirteen constellations that the Sun passes through during the course of the year are collectively known as the zodiac. Yes I said thirteen. During the early part of December the Sun passes through a region of the sky assigned to Ophiuchus. The figure below represents what the sky would look like at noon on December 11, minus that atmospheric effect. Notice that the Sun is not within the official boundaries of Scorpius, which is the normal astrological designation assigned to this time of year. The unidentified region of the sky is Ophiuchus. The reason it’s unidentified is that even in Starry Night, the program I used to produce these figures, there are only twelve zodiac members.
This brings us to the recent news stories about the zodiac shuffle. In a local story, astronomer Parke Kunkle of the Minnesota Planetarium Society, told reporters that the traditional astrological signs have shifted. In reality all that has been done is that someone took the time to calculate the exact dates the Sun passes through the zodiac constellations, including Ophiuchus, and compared them to the generally accepted astrological signs. This isn’t anything new. Astronomers have know for a long time about the existence of a thirteenth zodiac sign. At a minimum, you could argue it’s been known in the astronomical community since 1930 when the official constellation boundaries were accepted. It’s not a stretch either to argue that astronomers knew of this even before 1930 because some of the bright stars of Ophiuchus do dip down into the zodiac.
But that’s just the part of the story about the thirteenth zodiac sign. There’s still the bit about the shifting of most everyone’s astrological sign. For that we have to introduce some more science.
The Earth is continually executing three major motions: it orbits the Sun in one year, it rotates about its own axis in a day, and the Earth’s rotation axis wobbles (precesses). It’s the last type of motion we’re interested in here.
Precession is a slow wobble. Think of a child’s top like the one shown to the left of the below picture. A top will spin very fast about a central axis, but that axis will move around in a circle at a much slower pace. For the Earth, the precession rate is very slow. It takes approximately 26,000 years for the Earth’s wobble to complete one circle. The planet’s precession leads to two observable outcomes. The first is that the North Star changes in time. For now Polaris is the North Star, but in the future other North Stars will come and go. In 12,000 years, the bright star Vega will be the North Star.
This image was borrowed from Astronomy Today by Chaisson & McMillan.
The other result of the Earth’s precession is that the dates in which the Sun passes through the various zodiac constellations progressively changes. Because the Earth’s precession rate is very slow, this shift is likewise slow. Recall, that astrology has been around for thousands of years which isn’t the complete 26,000 year precessional rate, but it’s enough to offset the zodiac dates by a noticeable amount. In fact, the accumulative shift over the last few thousand years is about one whole constellation. The below figure is the same as before—noontime on December 11—but now the year is 4011. Notice how the Sun is now in Libra? In the two thousands years from today, the Sun has slowly drifted over one zodiacal sign as it has done in the thousands of years since the original astrological signs had been decreed.
Much like with the thirteenth zodiac member, the Earth’s precession has been known for two thousand years. So again, the shift in your astrological sign is old news to astronomers.
Astronomers now possess such accurate models of the Earth’s motions that they can tell you, or anyone that has or will ever live, their exact astrological sign. What you do with that information is up to you. Unfortunately the reason that these recent stories on changes in astrological signs have gone so viral is that a substantial fraction of the population seems to believe that the position of heavenly bodies have some kind of influence on their daily lives. Most any newspaper in America has a daily horoscope, but not a a regular science section. Ugh.
Astronomy as a Personal Inspiration
It seems lately that a lot of coincidental events have cropped up in my life. One of the latest is the idea that astronomy can inspire an individual. The latest xkcd comic, which I read this morning, greatly demonstrates how the wonders of astronomy can inspire an individual to compare the science of starlight to art.
I can relate to this comic in that I’m also inspired by astronomy. I remember one day, during my undergraduate years, I was sitting on my couch reading Stephen Hawking’s A Brief History of Time. At one point I paused in reading the book, looked around the room and the objects I interact with on a daily basis, and then thought it was amazing that somewhere out there in the Universe are these beasts of an object known as black holes. To think that common items like books, computers, cars, etc. that we’ve manufactured on this tiny speck of an Earth have nothing on what Nature has produced. That to me is what makes astronomy so interesting and inspirational.
Now for the coincidental part of my story. Yesterday, as it happened, I was also listening to an old Skepticality podcast in which Dr Michael Shermer is interviewing James “The Amazing” Randi. During the interview, Dr Shermer asks Randi (about 25:20 minutes in), “What catches your breath? What gives you a tingle in the spine?” Randi responds that taking out his personal telescope on the front lawn is what inspires him. The source of inspiration isn’t so much in the image but what occurs in making this image. Just like with the comic above, Randi likes to think about the fact that when he looks at distant objects it takes light some amount of time to travel to us. As an example, Randi talks about the Andromeda galaxy who’s light takes 2.7 million years to reach us on Earth. In other words, when we look at Andromeda we don’t see it as it is today, but how it was 2.7 million years ago.
James Randi takes it even further by commenting that what makes science even more inspirational is the fact that we, as humans, have the capabilities to contemplate such wonders and to make sense of them. Science can evoke emotional responses that both complement our understanding of a natural wonder while simultaneously causing personal inspiration. Two seemingly unlikely bedfellows, the strict rule following scientific mentality and the sometimes non-rational emotional responses, can come together to cause inspiration.
Gliese 581g: Are you really out there?
There’s something about astronomy that captures the imagination of the public. Unlike most other sciences, astronomy addresses some of the deepest and most cherished questions we have about ourselves. (I would also argue that evolutionary biology and recently neuroscience has also revealed a lot about human nature.) Collectively astronomy has given us a view of the Universe in which we’ve discovered that we’re not even justified in calling ourselves a speck. We’re located in an uninteresting corner of a great expanse. Through the subfield of cosmogony we’ve learned a great deal about how the Universe evolved after the Big Bang including how galaxies and stars form. Stellar astrophysicists have taught us that we’re all made of stardust. Even planetary scientists have discovered a number of essential features about solar system formation that may lead to life.
One of the foremost goals of astronomy has been to address the commonality of planets like Earth. Is our home special or are there many others like it out there? The reason we’re so interested in this question is that crawling all over the surface of Earth is life in many forms, some living in delicate ecosystems, others living under very extreme conditions (think extremophiles). If we could find other planets, and possibly a lot of them, then maybe there’s an abundance of life out there.
Hunting for earth-like planets around other stars is not trivial. The problem is Earth is relatively small both in size and in mass. Because of this the methods astronomers use to search for extrasolar planets tend to overlook earth-like planets. Despite the enormous challenges involved in looking for small planets, a collaboration of astronomers using the Keck Observatory in Hawaii discovered an earth-sized planet. (A preprint of their scientific paper can be found here.) This in and of itself is a special find—only a handful of other small planets have been found before. But what makes Gliese 581g, as it’s referred to, special is that it’s just the right distance from its parent star that the planet’s surface temperature should allow for liquid water. This is the first time an earth-like planet has been found in the habitable zone! Naturally there was plenty of news coverage. Not only that, one of the leading astronomers in the project went as far as to say, ”Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say, my own personal feeling is that the chances of life on this planet are 100 percent,” during a press conference.
Now the fun begins. One of the great things about science is that it produces testable results. After a discovery other scientists are not only invited, but are expected to verify the results. In this case, other astronomers need to find Gliese 581g for themselves. Unfortunately so far there has been no luck. At a recent International Astronomical Union meeting another group of astronomers announced that they could not confirm the existence of Gliese 581g when they looked at their independent data.
I love this announcement. Not because I have my own doubts about the original findings but because it demonstrates how science works. It starts with the hard work of a scientist, or in this example, a team of scientists. They make a major discovery that could advance the field by a large leap. But for this to happen, their work has to be checked. Enter a second, or possibly many other groups. Their job is to confirm the original findings and even sometimes to improve our understanding of the situation. If the second study confirms the first, great. Now a third, fourth, fifth, … group can also confirm it. However, when no confirmation can be made, then things get even more interesting. Everybody will go back to the observations, scrutinize the data, reconsidered the analyses, and possibly make new discoveries in the process. In the end, science makes progress regardless of the outcome. This is what distinguishes science from pseudoscience.
LIGO: Listening for Loud Bangs in the Universe
You may not be aware of it, but for the last eight years or so astronomers have been listening to the Universe. They’ve been doing so using the Laser Interferometer Gravitational-Wave Observatory or simply LIGO. Most astronomical telescopes that we’re familiar with are designed to collect electromagnetic radiation, which is just fancy talk for light. The output of these traditional telescopes are the familiar images we see on the news or popular websites like Astronomy Picture of the Day. Of course, many of the images released to the public have been enhanced or even adjusted to account for the fact that our eyes are only able to view a select kind of light, namely visible light (as opposed to the other kinds of light: radio, microwave, infrared, ultraviolet, x-ray, and gamma-ray). LIGO is an entirely different beast. It, or I should say they, were designed to detect gravitational radiation.
The idea of gravitational radiation is really straightforward. Just like shaking a charged particle produces light, shaking a mass produces the gravitational analog to light: gravitational waves. (Ok, they’re are some rules for how the mass has to be shaken, but that’s a minor detail here.) The production of gravitational waves is a natural consequence of Einstein’s general theory of relativity. Even Einstein knew they were a trivial byproduct of his theory, but he and his contemporaries also recognized a severe problem. Gravitational waves are an extremely weak phenomenon.
When a gravitational wave passes through an extended object it induces a strain in that object. In other words, the passing gravitational wave actually causes a change in the dimensions of the object. For LIGO the change in size caused by the expected gravitational radiation is in the neighborhood of 10-16 centimeters. That’s about a billionth of the size of an atom! This is why only now, 95 years after the discover of general relativity, has technology advanced sufficiently to allow astronomers to build detectors sensitive enough to measure such a tiny effect.
For the past eight years LIGO has been attempting to detect gravitational waves. Unfortunately they, nor any other gravitational wave detector, has had any such luck. Astronomers have never detected gravitational waves directly, only indirectly. But that’s okay. When LIGO was initially pitched to the National Science Foundation (the main funding source for LIGO), the original design goal was set primarily to reach a given noise threshold. It was known—as well as these things can be known—that the initial LIGO design probably wouldn’t detect anything. So why was it funded? Because if LIGO could reach the designed noise threshold within the time frame, then future upgrades would improve LIGO’s sensitivity to where it should detect gravitational waves. And that brings us to today.
Just this week, on October 20, LIGO completed its last science run. Over the next few months and years, the data will be scrupulously analyzed in hopes of dredging out a gravitational wave signal. In the meantime LIGO is going to be overhauled into Super LIGO. Actually it will go by the less spectacular name of Advanced LIGO. The upgrades will lower the noise threshold on the instruments, bringing them down to the level where the expectations for detection are much higher. In fact, I’ve heard it said that if Advance LIGO doesn’t make regular detections it will cause astronomers to rethink the event rates and distributions for gravitational wave sources.
Oh, by the way, what is LIGO and its future incarnation looking for? Only the coolest things in the Universe. The collisions of black holes, the mergers of neutron stars, and supernovas along with a few other gravitational wave sources. The best sources of gravitational waves are situations were massive yet compact (i.e. highly dense) objects are moving at extremely high speeds. LIGO is really searching for the exotic.
When LIGO does find something, don’t expect to see a pretty picture slapped all over the internet or on the news. Gravitational wave detectors don’t output images. They output sound. Recall that gravitational detectors monitor the change in the sizes the detector as a gravitational wave passes through. These changes in size are translated into an audio signal because the frequencies of the gravitational waves are very similar to audible frequencies. You can hear a sample of simulated gravitational wave sounds here. Even though gravitational wave astronomers aren’t able to retrieve an image of the source, they can still figure out a number of details about the source by studying the changing pitch in the signals.
So keep your eyes on the news about LIGO while LIGO keeps its ears open to the Universe.
