Wednesday, March 19, 2014

All mysteries solved??

I received an email from a relative, asking if the newly discovered “missing link” in astronomy now solves all the known mysteries. My original response was a defiant “No”—for how could observation of polarized light from gravitational waves at the time of the Big Bang, thereby proving inflation, be the answer to all of our mysteries? It definitely does not help answer the question of “how far away is epsilon Aurigae?” But it got me thinking about what impact this amazing finding will actually have on physics. Does it really solve all mysteries?

I first heard about the proof of inflation via a feed I get in my email. There is an excellent summation of what this really means on the Bad Astronomy blog from slate.com. It is quite a complicated finding, but let’s see if I can write a brief summary of what it is and what the BICEP2 B-mode figure means.




The published figure shows polarization (the lines) “ripples” in the Cosmic Microwave Background (CMB), which were created during the inflationary period at the beginning of the universe. The lines show how the light/radiation/CMB is polarized. (Your polarized sunglasses block out light polarized in a certain orientation) The CMB is left-over radiation from the beginning of the universe—it permeates everywhere (that is shown in the blue and red). It is how the polarization “curls” that is the signature astronomers have been looking for. This is indicative of gravitational waves interacting with the CMB.

Now, why does this matter? The figure below gives a lot of information, but the point is that the inflation period happened quickly and allows for the gravitational waves to polarize the CMB. So, it is essentially proof of how the universe came to be—it helps answer how everything is. It provides a link toward the grand unification where the strong, weak, and electromagnetic interactions are all unified (see the 3rd figure, here). This is a wonderful statement from Phil Plait of Bad Astronomy:

“Inflation is based on principles of quantum mechanics, while gravitational waves are the purview of relativity. QM has brought us computers, solar power, atomic energy—a huge amount of modern tech. Relativity is critical in many aspects of our lives as well, including GPS and also nuclear power. In the past these two concepts haven’t played well together, but now we have a direct and profound connection between them. This result is new, and we have a long, long way to go to understand it better. There’s no way to know what will result from this. Yet. But whenever we open up new fields of science, all sorts of interesting things follow. Bet on it.”



So, let’s refine the opening statement: it solves many mysteries, just not all; and it will open the door to more.

Friday, March 7, 2014

The Future of Space Science

NASA's 2015 budget was unveiled earlier this week and, not surprisingly, the numbers weren't pretty. The proposed budget is 180 million less than for 2014, for a total of 17.5 billion. But only about 5 billion of this is NASA's science budget.  Large amounts of money are required for other NASA programs, specifically anything related to human spaceflight.  For example, development on the Orion capsule and rocket will cost 2.8 billion for the year, and commercial spacecraft development another 850 million.

SOFIA
However, in order to pay the bills associated with human spaceflight, NASA has resorted to gutting its other science programs.  For example, it plans to cut funding for SOFIA entirely. SOFIA is an infrared observatory that is mounted inside a Boeing 747.  The advantage of this telescope is that it can get above much of the interference/absorption from the atmosphere that ground-based telescopes suffer from while flying, but when it lands repairs or upgrades can be made, which is difficult (or usually impossible) on space telescopes.  This is also an international project, so NASA is letting their partner space agencies down in addition to the scientific community.  Of course I'm paraphrasing, but it sounds like NASA's official stance is that if the Germans want to use SOFIA, they can pay for it.

Jupiter's moon Europa
Jupiter's moon Europa
Of course there are science programs receiving funding.  James Webb Space Telescope got 645 million to keep it on track for a 2018 launch, and Planetary Science is getting 1.3 billion. However, most of that money goes toward Mars missions. While I acknowledge that NASA's Mars program has had numerous recent successes and yielded interesting results, there are many other interesting targets in the solar system that are being ignored as a result of this almost singular focus.  One example is a mission to Europa, considered by some to be the likeliest place in the solar system to find life other than earth.  This received only 15 million in funding - just enough for so-called "pre-formulation work"...it isn't even on NASA's long-term roadmap yet.

Plutonium pellet
Plutonium pellet
There's also the question of powering a Europa orbiter, or any future deep-space mission for that matter. Because you receive less light from the sun the farther you get away from it, probes sent deep into the solar system can't rely on solar panels to generate their power. Instead, they use a radioisotope thermoelectric generator (RTG), sometimes called a nuclear battery.  These contain plutonium-238 (not the isotope that goes into nuclear bombs).  The plutonium heats up to over 1200° C, and that heat can be converted into electricity.  The Cassini mission to Saturn and New Horizons to the Kuiper Belt both use RTGs.  Both Voyager probes can attribute their long lives to the reliability of power from an RTG.  So, what's the problem?  NASA only has 36 pounds of plutonium-238 left (the previously mentioned Europa orbiter would require 47), and it hasn't been produced anywhere since the 1980s.  Due to lawmakers dragging their feet on restarting production, it's likely that all the plutonium-238 on the planet will have been used by the end of the decade.

While NASA's Orion project may provide future PR for the space program, it is enormously expensive.  If only a fraction of the 2.8 billion it will get next year (or the 3.1 billion it got this year) was diverted into restarting plutonium production, NASA could save its planetary science program. The same goes for the approximately 2 billion it would cost for asteroid redirection mission planned for 2025, which in essence "creates" a destination for Orion. However, it seems that even given the reality that NASA's budget isn't getting bigger, politicians and administrators continue to choose big, flashy missions that give good photo ops rather than the ones that can give the most science for the money.  Now stepping down from my soapbox...

Thursday, March 6, 2014

Cosmos: The book and TV series

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I guess many of you saw the promo for the upcoming show called Cosmos: A Space-time Odyssey. If you haven't seen it yet then you should definitely watch it http://www.youtube.com/watch?v=kBTd9--9VMI 
It is a 13 episodes television series featuring Neil deGrasse Tyson which will air in many television stations from March 9th. It is a follow up of 1980 Cosmos: A Personal Voyage by Carl Sagan http://www.youtube.com/watch?v=ClPShKs9Kr0 . You can watch all the episodes from the series in youtube. There is also a book titled Cosmos by Carl Sagan. This book and the television series have many crossovers as well as different content.
I highly recommend every one to watch this documentary as it is informative and easy to understand. If you prefer to read, then Cosmos will be a good read (in case you haven't read it yet). The book is written in plain English and you don't need to have science background to understand it. It is one my favourite books of all time. What I liked the most about this book was information on the history of science, astronomy in particular. He discusses about how different civilizations approached scientific endeavours. I was left in awe when I read about many historical persons who achieved so much at time when there was not much to work with. In addition to historical events there are many other interesting stuffs in this book. It tries to answer the basic questions about our cosmos which most of us have wonder at some point in our lives.
Do you have any recommendation for other good books?

Wednesday, March 5, 2014

Asteroids Galore!

Another asteroid just made a close approach! Asteroid 2014 DX110 was closest to the Earth at 4pm EST.

How close?   According to the officials at NASA's Jet Propulsion Laboratory in California, the asteroids closest approach was about 217,000 miles, which is about 350,000 km. Remember, the average distance from the Earth to the moon is 239,000 miles. That means this asteroid just passed between the Earth and the moon!

Now, for us here in Denver, or even those on the East Coast, the sun is still up. You couldn't see anything. Even for those people on the other side of the globe, you still couldn't see anything without a large telescope. This asteroid only has a diameter of 100 meters and thus is very, very faint. Even with some larger telescopes, this asteroid was moving so quickly, it was still hard to track.

The image on the right shows the asteroid that just made its close approach in relation to the background stars. 2014 DX110 is highlighted in a box and blown up so you can see what the object looks like. Mostly, it just looks like just another background star, except for the streak, which was caused because this asteroid is moving so quickly.





The image to the left shows the path the asteroid took as it made its close approach. The path that is depicted is how far the asteroid traveled in only 2 hours! Because this asteroid moves so quickly, it makes it very difficult to track. 





Why might you not have heard about this object? Most likely because it was only discovered last Friday, announced by the Minor Planet Center on Sunday, it is faint, and it won’t be impacting Earth. Although, Slooh hosted a live event detailing this asteroid as it made its close approach. You can watch it here and catch up on all the details.

During the show, the host mentioned that there is going to be another asteroid the will pass extremely close to us within the next couple of days. This object is 2014 CU13, an asteroid of about 20-46 feet in diameter. This asteroid will pass within 37,000 miles of Earth!! Slooh will be hosting another live show on Sunday to track this asteroid.

Sunday, March 2, 2014

Science kids

I was in a thrift store the other day looking through the vast number of available children’s books for my toddler son. Out of all of those books, I found a book with a black and blue cover with semi-purple lettering; there were white spots across the front and a misty, blue-purplish region in the upper left. Sure enough, it was the same book I had as a child: A Book About Planets and Stars.
I could remember spending hours staring through the pages and soaking in the variety of features our solar system holds in its planets. I don’t know how much influence that had on me choosing to become an astrophysicist, but I know I loved it then.

And just the other day, my 2 ½ year-old asked me to read him that book before bed. We went through the inner solar system (Mercury, Venus, Earth, Mars) and discussed (yes, discussed!) the differences between these planets. Okay, we just discussed the difference in color, but even then we talked about why. And I’m pretty sure he knows each of the names of the planets now.

Anyway, the point of this post is not to brag about my son, but to point out the importance of helping kids get excited about science/astronomy/physics. From television shows—for instance, Zoom, Bill Nye the Science Guy, and Sid the Science Kid—to youth programs—such as Odyssey of the Mind, FIRST LEGO League, FIRST, YAE— there are a lot of ways for children to participate and compete/learn.


The figure above shows data from APS, documenting the number of physics bachelor’s over the last 45 years, verse the number of bachelor’s in STEM fields (including the medical sciences). It is interesting to note the peaks of the physics numbers: the first peak follows the landing on the moon (1969); the second precedes the successful Pathfinder mission to Mars in 1997 (the first since 1976). I don’t know if the scientific programming as stated previously had anything to do with the increase since 2000, but it is great to see this increase occurring.

The important thing is to help spread the joy of science and discovery to people of all ages, especially those that will influence the path of science for the next generation. Any other thoughts of ideas?

And here are sum fun images regarding Moon and Mars missions from wikipedia: