26 Questions from General Conference

This isn't related to astronomy at all, but I thought I'd share a compilation of questions you can ask yourself taken from this past General Conference. There's 26 questions, one for each week until the next General Conference. You can think of this as a version of Alma 5...only not as long :)

1) Will we respond with love when an opportunity is before us to make a visit or a phone call, write a note, or spend a day meeting the needs of someone else? - Elder Rasband

2) Do you realize how deeply the Lord loves and cherishes you, even now? - Sister Reeves

3) Are we securely tied to God so that our faith shows, or are we actually tied to something else? - Elder Nelson

4) Where is our faith? Is it in a team? Is it in a brand? Is it in a celebrity? Even the best teams can fail. Celebrities can fade. There is only One in whom your faith is always safe, and that is in the Lord Jesus Christ - Elder Nelson

5) Why do any of us choose to be disobedient when we know the eternal consequences of sin?  - Elder Hales

6) How often do we make a mistake about the right way, letting ourselves be led along by the trends of the world?  - Elder Zivic

7) What does the phrase “no corrupt communication” mean to you? what would happen to the “corrupt communication” … if our own position included empathy for another’s experience first? - Elder Zwick

8) What changes are required of us to become the manner of men we ought to be? - Elder Hallstrom

9) What does your heart desire? What do you gravitate toward? Where will your desires lead? - Elder Ridd

10) Many of us immediately stop whatever we are doing to read a text message—should we not place even more importance on messages from the Lord? - Elder Ridd

11) Are you sleeping through the Restoration? - Pres Uchtdorf

12) When our time in mortality is complete, what experiences will we be able to share about our own contribution to this significant period of our lives and to the furthering of the Lord’s work? Will we be able to say that we rolled up our sleeves and labored with all our heart, might, mind, and strength? Or will we have to admit that our role was mostly that of an observer? - Pres Uchtdorf

13) All these things [hobby, a sport, vocational interests, and community or political issues], but are they leaving us time and energy for what should be our highest priorities? - Pres Uchtdorf

14) We will almost certainly be called upon to defend that which we believe. Will we have the courage to do so? - Pres Monson

15) None of us would wish to wear such a label [of hypocrite], and yet are we reluctant to declare our faith in some circumstances? - Pres Monson

16) Are you the same person wherever you are and whatever you are doing—the person our Heavenly Father wants you to be and the person you know you should be? - Pres Monson

17) How much of life do we miss by waiting to see the rainbow before thanking God that there is rain? - Pres Uchtdorf

18) Have we not reason to be filled with gratitude, regardless of the circumstances in which we find ourselves? Do we need any greater reason to let our hearts “be full of thanks unto God” “Have we not great reason to rejoice?” - Pres Uchtdorf

19) Brothers and sisters, can you imagine the impact if family and friends included things they are learning from their personal study of Preach My Gospel in their letters and emails to their full-time missionaries? - Elder Ballard

 20) Can you picture the blessings that will come to families when they know and understand better what their sons and daughters will be studying and teaching on their missions? - Elder Ballard

 21) Can you even begin to fathom the extraordinary outpouring of atoning grace that will be ours, individually and collectively, according to the Savior’s promise to all who bear testimony in the process of inviting souls to come unto Him—and then following up on those invitations? - Elder Ballard

22) You have the Savior of the world on your side. If you seek His help and follow His directions, how can you fail? - Bishop Stevenson

23) Is there someone who needs your encouragement? a family member? a friend? a classmate or fellow quorum member? -Bishop Stevenson

24) Is the load I am carrying producing the spiritual traction that will enable me to press forward with faith in Christ on the strait and narrow path and avoid getting stuck? - Elder Bednar

25) Is the load I am carrying creating sufficient spiritual traction so I ultimately can return home to Heavenly Father?” - Elder Bednar

26) Most of us know that when we do things wrong and need help to overcome the effects of sin in our lives, the Savior has made it possible for us to become clean through His redeeming power. But do we also understand that the Atonement is for faithful men and women who are obedient, worthy, and conscientious and who are striving to become better and serve more faithfully? - Elder Bednar

"Earth-like" Exoplanet Discovered!

Many of you may have seen the news about the "most Earth-like habitable planet" discovered. Well, the result is pretty convincing, but the implications may not be quite as grand as what people have been talking about...

First off, the discovery. The planet was found using the Kepler satellite, which is a space telescope that just looks at one patch of the sky (or did, until it broke). Kepler was looking for transiting planets, or planets that pass in front of their parent star from our point of view. When the planet goes in front of the star, we see a faint dip in the star's brightness. Detecting that small dip over and over again as the planet passes in front of the star strongly implies that there's a planet orbiting that star.

One of Kepler's mission goals was to determine how many Earth-like planets are out there. It's done a great job of finding tons of Earth-sized planets, but the planets its found are usually much, much too hot to really be Earth-like. Those planets are easier to find, but there have been a couple planets only slightly larger than Earth found in the so-called Habitable Zone of the star where the temperatures are just right for life.

This discovery was of a planet in the habitable zone of a star much fainter than the sun, known as an M dwarf class star. The really exciting part about the discovery is that the planet is only 10% bigger than the Earth, meaning it's basically Earth-like. Quite frankly, no planet has ever been found that's this Earth-like.

Now time for me to be a wet blanket. Finding planets like the Earth is great, but (you know there was going to be a but) this planet is way too far away for any sort of in-depth follow-up. Meaning even if there's life on the planet, we have no way of detecting it now or even in the near (next few decades) future.

Kepler has been great for finding Earth-like planets, but the next step is to find planets that are close by (at least, relatively close by. They would still be light years away!) And in fact, this is exactly what the 2nd part of Kepler's mission is - now that it's slightly broken it'll be looking at things a little closer to home. There are also plenty of new space telescopes coming along, like the Transiting Exoplanet Survey Satellite (TESS), that will enhance what Kepler has done.

The next step after finding nearby Earth-like planets is characterizing them. The upcoming James Webb Space Telescope (JWST) and upcoming extremely large telescopes (they're actually called 'extremely large') could be able to characterize Earth-like planets.

So when will I really get excited? Probably when we find a good target planet - a planet orbiting a nearby star that we can actually learn about. But that, unfortunately, will have to wait at least a few years.

Book Review: The Man Who Found Time

I just finished reading a biography of James Hutton, "The Man Who Found Time." Unless you're a geologist, you probably don't know who James Hutton is (I didn't before I read the book). But his discoveries profoundly changed how we think about the world and our place in it.

This won't really be a traditional book review; I'm not going to summarize the book and I'm not really going to critique it. All I'll say is, I really enjoyed it and it was a great refresher on the Scottish Enlightenment and the amazing ideas that came out of it that continue to shape the way we think.

James Hutton is the man who dared to defy conventional wisdom that the Earth was 6,000 years old. Yes, I know some people still believe that today, but just over 200 years ago everyone believed this, especially some of the most learned scholars in the world. They tried to explain the geology around them by using the flood and assuming that the great catastrophe of the flood and the waters receding back left everything that we see now.

Hutton's major breakthrough was realizing that rocks form all the time. As debris is eroded off of old rocks, it can gather at the bottom of a body of water, and over time enough pressure builds to turn the eroded material into new rock. This rock can then be lifted above the sea level by geological processes, which explains many of the formations he saw around him. The key here is that he realized that the process of erosion would take a very, very long time, meaning that for new rock to be formed, the Earth had to be extremely old. He didn't put a number on it, but he realized it was much more than 6,000 years old.

I think Hutton's discovery and story are incredible for two reasons. The first is that it's something that is relatively obvious in hindsight. Hutton's discovery required no advanced geological background; in fact, geology as a field didn't exist yet. He was a chemist, which certainly helped, but the things he saw could have been identified much earlier. Are there any problems like that today, where something is blatantly obvious once it's figured out, but it takes a veritable genius to crack the code? I think it happens fairly regularly on the scale of small problems, but what about big problems. If anyone knows of something like this let me know :)

The second thing that really struck me about this story was the intense backlash Hutton received for this theory.  The standard church doctrine was that the Earth was 6,000 years old, and no one really wants to go against that. I suppose we see hints of that today with so many people refusing to believe in an Earth that's older than 6,000 years old, but in Hutton's time the backlash came from fellow scientists. I've heard similar stories about this happening in science today, but rarely does it last someone's entire life like it did for Hutton.

Reading this book made me glad that I'm a member of a church that respects science. The church doesn't have an official stance on the age of the Earth or evolution, leaving room for science to do its job. And this makes sense. The church's job is to bring the gospel to people, not force scientific ideas on people. The church (and of course, God) care much more about our spirituality and whether we're keeping our covenants than whether or not we adopt a literal interpretation of the biblical creation story. Learning about science is encouraged, and is something that can help us later in the eternities.

Why do we have four limbs?

One of the greatest things about Astrobiology is how expansive it is - it literally includes everything "in heaven and in the earth, and under the earth; things which have been, things which are, [and] things which must shortly come to pass" (DC 88:79). Today's entry is about the topic of evolution, which is not my main field of study, but is something that falls under the purview of astrobiology.

Today I came across this article from the science news site Science Daily, which by the way, is a site I really like for news from all fields of science. The article is on animal evolution, and specifically about why we have four limbs. It's been known for quite some time that all mammals. birds, reptiles and amphibians are tetrapods, meaning they have four limbs. The limbs could be fins, wings or arms and legs (or even tiny stubs that you'd never notice), but they're all related to each other. But the reason for why all these animals have four lime is still an unsolved problem in biology.

The researchers were studying animals hatchlings and embryos and comparing physiological features. (From Science Daily)

Very early in the development of all the embryos the group looked at, the embryos form into 3 distinct layers, known as germ layers. Each of the three germ layers has a specific purpose - the ectoderm (outside layer) generally forms the skin and nervous system, the endoderm (inside layer) forms the digestive tract and many other essential organs, and the mesoderm (middle layer) generally forms muscle, tissue, bone and other parts of the body.

Very early on in an embryo's development the mesoderm splits into two separate layers. The hypothesis presented in this paper is that pairs of limbs can only form where these mesoderm layers interact with the ectoderm. Between these points, they propose that limbs simply can't form because the gut is developing.

Sorry, no centaurs allowed in this universe apparently.

But I suppose a god may be able to muster a one or two (dozen) extra arms

To be completely honest, reading about this left me with a lot more questions than answers, but parts of it make sense. The gut is really the most important part of any organism. Without the ability to have energy sources come in and be turned into something the body can use, the organism dies. I could imagine that growing an extra leg or two right next to the developing digestive system might interfere with survival. That being said, I'm still not sure why limbs can only form there, or how exactly this process happens.

The spiritual conclusion I came to while reading this is that we really are created in God's image. There's something innate about the way we look that isn't random. It could be that the laws of physics simply don't allow anything else. I don't know though, that's pure speculation. What I do know is that God created this Earth and everything on it with a plan. Call it intelligent design if you'd like, but I know that as we keep learning about how evolution worked that more things like this will be discovered, and we'll see God's hand in the entire process.

The full paper is available for free here. The title is "The lateral mesodermal divide: an epigenetic model of the origin of paired fins," Evolution & Development, 2014 by Laura Nuño de la Rosa, Gerd B. Müller, and Brian D. Metscher from the University of Vienna.

"Worlds Without Number" - Exoplanets and LDS Beliefs

In Moses, we read that God has created "worlds without number" (Moses 1:30) and it is strongly implied that many of these worlds have inhabitants on them that are similar to us.

In my last entry I wrote about finding and characterizing Earth-like planets, and I just glossed over the fact that we actually have discovered thousands of potential planets around other stars, known as extrasolar planets or exoplanets. This is one example where science has corroborated revelations given nearly two centuries ago, in that we think the number of worlds or planets in our galaxy like numbers in the 100's of billions - certainly enough to qualify as "worlds without number."

Diagram for the radial velocity method to detect exoplanets.

First, a little bit of background on exoplanets and how they're discovered. The first exoplanet around a star like the Sun was discovered in 1995. The way it was discovered was by looking at the slight change in the star's position from the planet. You see, we think of planet's orbiting around stars and the stars staying put, but in reality the star "orbits" around the planet too - it just moves far less than the planet does. So as the planet moves around the star, the star moves in response. When the star's position changes, it's velocity or speed towards us will change, and then we can take advantage of a physical effect known as the Doppler Effect. Everyone knows what this is even if they don't know the term - you know when a fire truck or ambulance is coming towards you and you can hear the pitch of the siren change as it passes you? That's the Doppler Effect, only instead of talking about the pitch (or frequency of the sound) change, we're talking about the frequency (or color) of light changing. So as the star moves in it's "orbit," we see it's color change a very minuscule amount, and from that we can infer that there must be a planet orbiting the star.

How transit work - we see a dip in the star's
brightness and infer a planet must be there.

The other main method of detecting a planet is called the transit method. This is one is thankfully much more intuitive. For certain planet-star systems, the orientation is just right that we can actually see the planet pass in front of the star, like in an eclipse. Planets are much, much fainter than stars so when the planet is in front of the star, we see a decrease in the amount of light from the planet, and based on the amount that the light decreases by we can not only tell that there's a planet, but also how big the planet is relative to the star. You might have read news articles about planets being discovered by a mission called Kepler. The Kepler spacecraft stared at one spot in the sky for more than 3 years looking for transiting planets, and it found thousands of them. It's made the transit method the most successful method for finding planets to date.

So now that the background is out of the way, what do the results mean? Well, first off, we've found a lot of planets. You can check this site to get an up to date count, but as of right now we're at over 1,000 confirmed planets and over 3,600 planet candidates (likely to be planets, but need follow-up observation). Based on the statistics from missions like Kepler, there should be billions of planets in our galaxy alone, and in the universe, probably trillions.

But I think the most interesting part about all these discoveries is that God thew a bunch of things at us that we never expected. A lot of people more or less assumed that exoplanet solar systems would be a lot like our own solar system - rocky planets in the inner part, gas giant planets in the outer part, all with nice and neat circular orbits. But that's not what we've seen at all. We've found that about 1% of stars have what are called Hot Jupiter planets, planets that are the size of Jupiter but found 10 times closer to their star than Mercury is to our Sun. There have been planets found with highly elliptical (non-circular) orbits, and also planets in multi-planet systems where the inclinations are completely misaligned - meaning that instead of the orbits lying on a flat surface, they criss-cross each other. There are a lot of planets that have sizes between Earth-sized and Neptune-sized, things that we really don't know anything about because we don't have anything like that in the solar system. It really seems like God has created every single planet he possibly could in this wondrous universe.

It's tempting for me to think that our solar system is unique and that it's not possible to have life on a planet without having the exact right setup, but I'm sure I would be proven wrong eventually. The neat thing about these planets is that they're all, in some way or another, created to bring to pass the work of Heavenly Father - the immortality and eternal life of His children, which includes us! Even in our own solar system we have 7 other planets, countless moons and dwarf planets and a large number of asteroids and other small objects, and it's all for us. How amazing is that? And more so, how humbling is that?

So in conclusion, in exoplanets, as well as in our own lives, God helps us to remember that He knows far more than we do. He is constantly surprising us and throwing new concepts and challenges at us. There are indeed "worlds without numbers" out there, in all shapes and sizes and there will be things we never expected to see, but God knows all His creations, and He has created them for own purpose - to save His children.

The Quest to find an Earth-like Planet

This is a tremendously exciting time to be an astronomer, or just anyone with an interest in science. Why? Because of fast-paced field of exoplanets, or planets around other stars. There's way too much about this field to cover in one post, but to keep it short, the progress that's been made in a relatively short amount of time is amazing. Less than 20 years ago, the first exoplanet was discovered. A couple decades and thousands of planets later, we're not just discovering exoplanets, we're also starting to be able to characterize them and learn about their atmospheres.

I was at the American Astronomical Society (AAS) meeting in Washington D.C. a couple weeks ago. This is the biggest astronomy meeting in the world, with about 3000 people registered for the conference. At the meeting, there were several talks about an observational technique called transit transmission spectroscopy, which incidentally happens to be what my dissertation is on. For some exoplanets, the exo-solar system is aligned just right that our viewing angle lets us see the planet pass in front of the star, or transit. This is one of the main ways we discover exoplanets - by looking for the dip in the star's light as the planet transits it. But what's more interesting to me is that some of the star's light passes through the planet's atmosphere, where it can be absorbed and scattered by molecules and particles in the atmosphere. The atmosphere leaves a spectral signature on the light, which can then be used to figure out what the atmosphere is made up of and potentially even the pressure and temperature that we can see.

Animation of a transiting planet. We see a dip in the star's light when the planet passes in front of the star

You can imagine that you need pretty good precision to be able to do this. Star's are incredibly bright, and planets are, well, not very bright at all. The percentage dip in stellar light from a transiting planet is maybe 1% for a lot of the planets being characterized (for a true Earth-like planet, it'll be closer to 0.01%). But that's for the planet as a whole. For just the atmosphere, the signal can be a lot lower. The current best precision is 30 parts per million. To give you a sense of how small that is, look at a light bulb in the room you're in. Now put a speck of dust on the light bulb. No, not a dust mite, literally a speck of dust. The decrease in the light bulb's brightness is about 30 parts per million. That's the level of precision we're getting for stars that are light years away.

But 30 parts per million isn't good enough. What we really want is to able to characterize the atmosphere of something like the Earth. And to do that even to the most minimal level we need to be precise enough to get 10 parts per million, and to be able to detect things like oxygen (which is a biosignature for photosynthesis and a very strong indicator of life) you'd probably need at least 1 part per million precision. Again, 1 part per million for a star that's light years away. Thankfully, we might actually be able to do this within the near future. The interesting thing about getting very precise measurements is that for these types of observations, the longer you look at something and the bigger the telescope you have, the better your precision. The current observations are using the Hubble Space Telescope for near 60 hours on one star. Within about 10 years, the James Webb Space Telescope, which has a collecting area about 7 times larger than Hubble.

So with the James Webb, it should be possible to actually get a good look at an Earth-like atmosphere within the next 10-15 years. I'm not saying it'll be easy, but it's at least possible. If there is another Earth out there that's relatively close by, we'll be able to find it and learn about it's atmosphere.

Did Life Originate from a Global Chemical Reactor?

The origin of life remains one of the most open scientific questions in Astrobiology. While there's been great headway in both laboratory and theoretical understanding in how life may have originated, we still don't know when, where or how life originated.

Today's post revolves around this paper by Eva Stueken and others (mostly from the Univ. of Washington) I just reviewed in a seminar on a theory for the origin of life that looks at the early Earth as a global chemical reactor that could have led to the right reactants coming together to make life. The paper is open access, meaning anyone can go ahead and download it. The punchline of the paper is that instead of being a random event that occurred on the early Earth in one habitat, the origin of life was a more gradual process relying on multiple reactions from all over the Earth.

Most theories for the origin of life assume that life originated in one fairly limited region of the early Earth. This new theory looks at the exact opposite idea - what if life couldn't have formed in an isolated habitat? What if it required chemical reactions and transport schemes occurring all over the planet, perhaps not even at the same time?

The authors look at 8 different locales on the early Earth - the atmosphere, lakes and rivers, beaches, sea-ice, sea-surface micro layer, marine sediments, hydrothermal vents, and the oceanic crust. Each local has certain chemical reactions that are favored. For example, only places on or very near the surface have access to sunlight, which is important for a lot of the reactions believed to be necessary for life to form. On the other hand, hydrothermal vents are major sources of metals into the ocean, and therefore could play an essential role in the origin of life. Some people have even gone as far as to say that hydrothermal vents alone are where life originated.

Once the reactions occurred in each environment, there need to be various transport mechanisms to get the reaction products from one area to another. Thankfully, between winds, currents, tectonic outgassing and even convection in the crust, there's no reason to believe that this wasn't the case. So you could have molecule A form in a lake on the surface, molecule B form near a hydrothermal vent, molecule C from the sea-surface micro layer, and they all get together on the beach and suddenly...A+B+C = life.

Scientifically and theologically, the implications of this are profound. This is a hard theory to test, but if it were true, that would change the origin of life from a somewhat random event that relied on a specific chemical reaction occurring in one location to a more gradual, deterministic event that doesn't seem so improbable, if you have the right conditions.

What are the right conditions? It seems to be that you need a wide variety of environments. So perhaps if you have a planet like the Earth in the habitable zone of another star, life would have a high probability of forming.  But what about a world like Europa, where the ocean is (mostly) cut off from the surface? Well, if there might be mechanisms to transport products from the surface to the ocean, but it doesn't seem as likely as life originating on an Earth-like planet.

What does this mean theologically? That's a bit more speculative, but we know that we are created in God's image, so it would make sense if God put a system in place to have life originate in places like the Earth. It's not scientifically obvious that evolution would automatically lead to homo sapiens (most scientists would argue it wouldn't) but there's still so much we don't understand about this topic.