Science and Religion are Compatible

As a scientist who strives to provide public access to science, I applaud the wonderful article by Lori Kozlowski about science and society in the Los Angeles Times on August 22, 2009, and wish to contribute some thoughts.

Contrary to what some scientists and some non-scientists stridently proclaim, I believe science and religion are compatible – both are organized efforts to find Truth. Best go to science to find the distance to the Sun, the age of the Earth, or similar questions whose answers are numbers. But science has not, and in my view never will, determine whether or not God exists, what is the purpose of human life, or to what ethical code good people should aspire. Science is incapable of answering such very important questions.

Science is not an obscure cult practiced by estranged people. Science is simply the extension of everyone’s innate curiosity. Children continually ask Why? They are born wanting to learn about and understand their world. Scientists are just people who never stopped asking Why?

Science should be for everyone. Just as you don’t have to be a great musician to appreciate great music, you don’t have to master complex math and technical jargon to appreciate the exciting discoveries of modern science. We live in the Golden Age of Science – more has been discovered in our lifetimes than in the entire prior history of mankind. We have found nature’s smallest parts and have seen out to the edge of the universe and back almost to the beginning of time. These exciting discoveries can be presented so that everyone can participate. I have given science talks at a wide range of venues from major universities to the Latina club of a local middle school. Audiences everywhere and of all ages have the same desire to understand more about their world. They just need information they can digest.

Science has not just increased our academic knowledge, but has also added to our wealth and welfare. A century ago, life expectancy in the U.S. was 47 years. In a single year, 40 million people died of the flu worldwide. Only 6% of Americans graduated from high school, and there were no iPods, DVDs, cellphones, internet, GPS, lasers, radio, movies, or television. In 100 years, our life expectancy has increased to 78 years, and of Americans over 25, 85% now graduate from high school and 27% earn college degrees. Most of these improvements are due to the advance of science and technology.

Looking forward, science is how we will reduce our dependency on foreign oil, mitigate pollution and solve global warming. It behooves the public to better understand science, so they can more knowledgeably participate in determining what sort of world we will leave to our children and grandchildren.

EPA Should Not Deny Public’s Right To Know

An EPA decision to restrict greenhouse gas emissions may be of some benefit to the climate, but it certainly will substantially increase energy costs and unemployment as more jobs will be lost to countries without such restrictions. As a scientist and a taxpayer, I strongly believe the public has a right to a fair and open hearing and examination of the evidence supporting restrictions that will have such far-reaching impact.

As reported in the LA Times on August 25th, EPA spokesman Brendan Gilfillan claimed no public hearings were necessary because scientific evidence “overwhelmingly indicates that climate change presents a threat to human health and welfare.” However, nothing was said about any evidence that human activity is the cause of climate change, or that restrictions on the U.S. economy will solve this problem despite the most populous and most polluting nations continuing their rapidly increasing emissions.

I was particularly appalled by the reactionary comment of Brenda Ekwurzel of the Union of Concerned Scientists who compared a public inquiry to a witch hunt. Scientists who aren’t willing to publicly present their data and defend their conclusions should get out of science and become political lobbyists, no doubt that pays better. Oh, maybe some has already thought of that.


Please visit my website: http://www.guidetothecosmos.com or email me at cosmos.guide@sbcglobal.net

Hubble Proved the Universe is Expanding

Edwin Hubble, after whom the newly repaired space telescope is named, used Henrietta Leavitt’s discovery to leap beyond the reaches of our galaxy. Hubble observed (before there were any space telescopes) that galaxies throughout the universe are moving away from Earth at velocities that are proportional to their distances from Earth; this is called Hubble’s Law.

We should not interpret Hubble's Law to mean that Earth is the center of the universe, nor that each galaxy is flying through space with a velocity that just happens to obey a certain formula. It doesn’t seem reasonable that each of the hundred billion galaxies just happens to have the right velocity. There must be some mechanism, some profound principle of nature, that choreographs this cosmic dance. The choreographer is space itself. What is really happening is that space is expanding and carrying with it everything it contains. As the space between galaxies expands, they move apart. Every location in the universe can lay equal claim to being the center of expansion – the universe expands in the same way as seen from every location.

Consider a simpler example. Imagine a strip of elastic tape with coins attached to it. If we stretch the tape, the coins will move apart. Now think of each coin as being a galaxy. Astronomers in each galaxy will observe all other galaxies moving away from them. They will observe galaxies that are twice as far away moving twice as fast, because there is twice as much tape stretching between them. They will discover Hubble’s Law. It isn’t really the galaxies (coins) that are moving, it’s the space (tape) between them that is expanding. In this example of a stretching tape, the expansion is in only one dimension. But, in our universe, all three dimensions of space are expanding at the same time and at the same rate.

View my video: YouTube Video

Hubble's Law Proves the Big Bang

What is the meaning of Hubble’s Law, which says that all the galaxies in the universe are moving away from Earth at velocities that are proportional to their distances from Earth?

Hubble’s Law leads us directly to conclude that the universe is expanding and that it had a beginning – the Big Bang!

To understand this, consider a simpler, down-to-Earth example. Imagine that we were on the top of the Seattle Space Needle (on a clear day in Seattle) using a telescope to look at traffic leaving the city for a long weekend. Also imagine that we discover that every vehicle on the road happens to be moving away from us at a velocity proportional to their distance (Hubble’s Law v = H d). Thus if we see a minivan 75 miles away going 25 mph, we know H = 1/3. And if we see a sports car 150 miles away, it must be going 50 mph per Hubble’s Law. If none of the vehicles changed their velocities, then where were they 3 hours earlier? Since the minivan covers 75 miles in 3 hours (25 mph times 3 hours), and it is 75 miles away now, it must have been at the base of the Space Needle 3 hours ago. Similarly, the sports car covers 150 miles in 3 hours, so it too was at the Space Needle 3 hours ago. In fact, if every vehicle on the road is obeying Hubble’s Law, then every one of them must have been in the same place 3 hours ago (probably when everyone got off work). This must be true because we can rearrange Hubble’s Law to read d – v/H = 0.

What’s all that got to do with the universe? If all the galaxies are moving away from us at velocities proportional to their distances (Hubble’s Law), as we observe that they do indeed, then all the galaxies must have been in one place at one time long ago – we call that moment the Big Bang.

Hubble's Constant and the Expansion of the Universe

We discussed earlier how Henrietta Leavitt discovered how to use Cepheid variable stars as one of astronomy’s most precise “standard candles” to measure vast distances. Edwin Hubble built on Leavitt’s discovery to make some of the most important scientific advances of the 20th century.

Before Hubble’s work, astronomers thought our galaxy, the Milky Way, was the entire universe – they really didn’t have a concept of galaxies being separate structures within a larger universe.

Starting in 1919, Hubble began measuring the period and apparent brightness of numerous Cepheid variables in various so-called “nebulae” that were then thought to be fuzzy patches with “lots” of stars. In 1925, Hubble announced his findings. Using Leavitt’s work, he found that some of these “nebulae” were immensely farther from us than the rest of the Milky Way. And to be as bright as they appear to us, they must have billions of stars – they must themselves be separate galaxies, some comparable or even larger than our galaxy. Almost overnight, our concept of the size of the universe was literally blown away – its vastness was far beyond anyone’s wildest dreams.

In 1929, Hubble went even further. He combined his galaxy distance measurements with “redshift” measurements of the same galaxies. Redshifts are changes in the frequency of starlight that allow us to determine a star’s (or a galaxy’s) velocity. What Hubble discovered was that almost every galaxy was moving away from us, and for distant galaxies, their recessional velocity was proportional to their distance from Earth. In math, this is written v = H d, where d is the galaxy’s distance away, v is its recessional velocity, and H is a number we call the Hubble “constant.”

Based on Hubble Space Telescope data published by NASA two weeks ago, we now know H = 51,000 mph per million light-years, to a precision of 5%. (A light-year is the distance light travels in one year, about 6 trillion miles.) This means a galaxy 10 million light-years away is moving away from us at 510,000 mph, and a galaxy 100 million light-years away is moving 5.1 million mph.

The value of H has an enormous impact on the evolution of the universe. For nearly a century, measuring H has been one of the most important and most difficult tasks in astronomy and the source of great controversy. Edwin Hubble’s first measurements were about 7 times too high and had a very large measurement uncertainty. Even as recently as the 1990’s, some astronomers believed H was twice as large as what others thought. Using the space telescope named in his honor, Hubble’s constant has been measured with great precision.

More on Hubble

Edwin’s Hubble’s famous discoveries about our universe were made possible by the remarkable work of Henrietta Leavitt. Overcoming her deafness and male chauvinism, Leavitt became the first famous American woman astronomer by solving one of astronomy’s greatest challenges.

After graduating from Radcliffe, Leavitt joined the Harvard Observatory in 1893 as a low-level technical assistant – women were not allowed to operate telescopes at that time. Her job was to count stars on photographic plates and measure their brightness.

Leavitt saw beyond her mundane task and discovered a special relationship for stars of a certain type — Cepheid variables. These are stars whose brightness waxes and wanes in a regular periodic fashion. Several types of stars vary in brightness, but Leavitt relaized that among Cepheid variables, the longer it took the star to go through its brightness cycle the brighter the star was at its peak. In fact, Leavitt demonstrated that from the length of a Cepheids’ cycle, its “period”, the star’s true, or “intrinsic”, brightness can be determined with great precision. Then by measuring how bright that star appears to us on Earth, its distance from Earth can be calculated. Leavitt discovered how Cepheids could become one of astronomy’s most precise “standard candles.”

As the notion of standard candles is of great importance in astronomy, it merits a bit more explanation. Imagine looking down a residential street at night and seeing a row of porch lights. If we knew that each house had a 100 watt blub on its porch, and we knew the distance to the nearest house, we could figure out the distance to every one of the other houses. We would measure how bright each porch light looks from our house and use the fact that the intensity of light drops with the square of the distance it travels – the light from a house twice as far away will appear one-quarter as bright. Astronomers can identify Cepheids, measure their periods, and, using Leavitt discovery, compute their distance.

This was huge! Measuring the distance to very remote objects has always been the most challenging task in astronomy. Thanks to Henrietta Leavitt, astronomers were finally able to measure vast distances – distances on a galactic scale and beyond.

With Leavitt’s discovery, Hubble forever changed our view of the universe. He recognized the importance of Leaviit's contribution and recommended that she be awarded the Nobel Prize in Physics. Unfortunately, Leavitt died in 1921, before the completion of Hubble’s work, and Nobel Prizes are not awarded posthumously.

Launch of Hubble Space Telescope Repair Mission

On Monday, May 11th, NASA launched the fifth and final repair mission for the Hubble Space Telescope (HST). Originally launched in April 1990, HST has provided some of the greatest advances in our understanding of the universe. The repair mission will replace failed gyroscopes, batteries and instruments, extending the life of the world’s most important telescope to 2014, and perhaps beyond.

The chart illustrates just how powerful the HST truly is. The chart shows how the amount of detail that astronomers could observe has grown over the last few centuries. Before 1609, astronomy was done solely with the human eye, which can resolve details as small as 1/50th of a degree. In 1609, Galileo pointed the first telescope at the heavens and was able to see about 600 times more than has ever been seen before. The world is celebrating the 400th anniversary of Galileo’s advance by declaring 2009 to be the International Year of Astronomy. As the chart shows, in the 400 years since Galileo, steady progress was made with ever more powerful telescopes. But all these pale in comparison to the dramatic advance achieved by the HST, which has provided almost 3 million times the information that can be seen by eye.

HST has opened a Golden Age of astronomy and opened our eyes to a more profound understanding of our universe and our place in it.

More on the telescope and the science later.

Now, we hope for the success and safe return of Space Shuttle crew Andrew Feustel, Michael Good, John Grunsfeld, Greg Johnson, Michael Massimino, Megan McArthur and Commander Scott Altman. These seven brave astronauts have trained for years and have accepted considerable risk to restore one of the greatest scientific instruments in human history.

Visit my Video: YouTube Video.