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Astrophysics Book Review – Space: 10 Things You Should Know

11 Friday Oct 2019

Posted by in Astronomy, Book Review, Communication, Education, Entertainment, Exploration, Higher Education, Information Technology, Internet, NASA, Passionate People, Photography, Print Media, review, Science, Social Interactive Media (SIM), Space, Technology, Traditional Media, Universities, Women, Writing

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Minding the Gap of Knowledge

Sharing the knowledge of scholars (e.g.; astrophysicists) with non-scholars is difficult. Astrophysics scholars have spent years obtaining a foundational understanding of the dynamics of our universe that is not obviously known to the public. They also have a working knowledge of special terms, acronyms, and highly cited authors. This creates a chasm with scholars on one side, who are advancing human knowledge, and non-scholars on the other side, unaware of the progress and activities of those in the field.

As scholars tend to be focused on their work and the work of their peers, it is rare to have a scholar attempt to bridge the chasm and help non-scholars have access to the secrets that have been uncovered and the challenges to be overcome. 

Dr. Becky Smethurst, astrophysics researcher, educator, YouTuber, and author

Dr. Rebecca Smethurst, or Dr. Becky as she is known on her YouTube channel, is one of those rare scholars who is diligently immersed in sharing new knowledge and discoveries in astrophysics with the public as she actively participates in furthering our understanding of it. In her new book, Space:  10 Things You Should Know, (2019) Dr. Smethurst continues to inform and enlighten us about what humans know and don’t know about the development of galaxies and the stars within them.

Review – Space:  10 Things You Should Know

Category:  Nonfiction, Science, Non-Textbook

UK/Europe Release: 5 September 2019 by Seven Dials Publishing
North America Release:  Summer 2020 by Ten Speed Press

Informative  ★★★★★
Relevancy  ★★★★★
Readability  ★★★★☆
Half-Life  ★★★☆☆
Expertise  ★★★★★
Visuals  ★☆☆☆☆

[Formats: Hardcover, Audio]

Dr. Smethurst has written multiple scholarly articles; however, this is her first book. It is a short, easy-to-read work of 10 chapters. Each chapter reveals information about our universe that may not be part of public awareness. 

The book is written in conversational language, not scholar-speak. It provides a basic knowledge of what we know about the formation of the universe, galaxies, and planets (including the Earth.) Amateur astronomers likely know most of this information, but Dr. Smethurst provides nuggets of new information that make the book worthwhile to read.

She begins with a view of how gravity is critical to how the universe functions. Because her work deals with supermassive black holes, Dr. Smethurst discusses what we know about black holes and theories of how supermassive black holes impact the galaxy they’re located in.

Dr. Becky also discusses Dark Matter, why scientists believe it is real, and what it means in the grand scheme of the universe. Two other chapters talk about the hunt for planets outside of our solar system and the practicality and current limitations of human space travel.

This book could serve as a unit in a middle or high school science class, but it is just as functional as a broad-based survey of current astrophysics knowledge for adults who can read above a sixth-grade level. As a first book by a doctorate-level scholar for consumption by the general public, it is brilliant.

As one might expect with a book of this nature, the subject matter is fleeting. As Dr. Smethurst states in her preface, “…science moves quickly…” Though this is not a textbook, it encounters the same problem as most textbooks in that research and discovery move forward while the printed book remains unchanged.

My projection is that the half-life of this is about seven to ten years. After that, about half of the information will become less relevant as new discoveries push astrophysics forward. That said, this book is certainly not a wasted effort and the need to persevere with updated information is critical.

If this book were a second or third book by this author I would expect to see a more expansive book and more visually stimulating. Both Carl Sagan and Brian Cox have used television and print to ignite a passion for science in the minds of the public. Their books are filled with images that help the reader to see science as a living entity filled with wonder and adventure.

Dr. Becky uses imagery extensively on her YouTube channel so it is likely that we can expect future books to have a greater visual element.

Still, as a first book, coupled with her YouTube work, Dr. Smethurst has built an impressive bridge to reach out to the public. As an active researcher, she offers a unique opportunity for non-scholars to access scientific information from a knowledgeable source rather than the entertainment-based news media.

Dr. Rebecca Smethurst is the one to keep a telescopic eye on.

Dr. Becky’s Astrophysics Work

Understanding The Life and Times of a Galaxy

In the last 100 years, our ability to visualize the stars has vastly improved but the galaxies we see today have changed very little in the past 10,000 years. Changes in the shape and location of a galaxy take millions of years to occur so what astronomers see today isn’t that much different than what they could have seen thousands of years ago.

What astrophysicists do know is the relative age of a galaxy. When we image a galaxy that is ten million light-years away we are seeing how it looked ten million years ago. By using the relative age of a galaxy and the characteristics of that galaxy, astrophysicists can identify group traits of similar galaxies and begin to understand how galaxies develop and eventually die.

The work of Dr. Smethurst has been to increase our understanding of the role of a galaxy’s core black hole (supermassive black hole) in the development of a galaxy and of its ability to establish new generations of stars. The current theory is that as the galaxy matures the core supermassive black hole sucks much of the free hydrogen out of the galaxy. Without an adequate source of hydrogen, the fuel for the formation of new stars is depleted and the galaxy becomes inactive. 

Dr. Smethurst’s Scholarly Astrophysics Linage

Dr. Smethurst’s advising faculty for her doctorate program was Dr. Chris Lintott. Since 2013, Dr. Lintott has been a co-presenter for the BBC’s enduring documentary astronomy television program, The Sky At Night and is a co-founder of Galaxy Zoo, an online crowdsourced project to engage the public in helping to categorize millions of galaxies for research purposes. Dr. Lintott’s advising faculty included the highly published and cited cosmologist Dr. Ofer Lahav.

Dr. Becky earned her Master’s degree in Physics with Astronomy at the University of Durham and her Doctorate degree in Astrophysics at the University of Oxford. Currently, she is a Junior Research Fellow at Christ Church College at Oxford University. Her focus is on studying galaxies and their interactions with their core supermassive black hole.

In 2014, [23 April 2014] Dr. Smethhurst was asked where she saw herself in five years. Her response was, “I’d look to reach the most amount of people as possible…to spread the word about the amazing things that people have no idea about.”

…to spread the word about the amazing things that people have no idea about…

Dr. Rebecca Smethurst – 23 April 2014

Now, five years later, Dr. Smethurst is achieving that goal through her new book, her YouTube channel, and her outreach work.  

Dr. Becky Smethurst

Dr. Becky on:

Sample of co-authored published work:

 

Ten Reasons There is Life on Earth

21 Wednesday Mar 2018

Posted by in All Rights Reserved, Astronomy, Exploration, Global warming, Green, History, Life, NASA, Nevada, Reno, Science, Space, US Space Program, Water, Weather

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As scientists are finding more planets orbiting other stars it is becoming more of a reality that we are not alone in the universe. We may never be able to contact or observe life on other planets, but no one can deny the possibility that life might take root these islands in space. Still, it is important to remember that life on Earth is due to special circumstances.

Ten Factors Required For Life On Earth

A planet orbiting a star does not necessarily result in the development of life. On our planet, we have at least ten factors that allowed life to develop.

1. Not Too Close to Other Stars (Location, location, location)

If our solar system was located near the center of the Milky Way Galaxy, life probably would not have been able to develop on Earth. Stars are dangerous. They do bad things including spitting out radiation that destroys the basic structures of complex life. A planet in a solar system with other stars in the neighborhood is asking for trouble.

2. Our Sun is Special

Life on any planet requires a star, but not just any star will do. Size matters in the development of life. So do the qualities of the star. Our Sun is bigger than most, but still it is a relatively small, stable star and it’s been that way for over four and a half billion years. It will be stable for about another 5 billion years. It also has a treasure of heavy elements that are necessary for planet formation. Without planets, there is no life.

Life around stars of different sizes are possible, but our Sun seems to be about the perfect size for the development of life. In addition, our Sun is 85% brighter than the rest of the stars in the Milky Way, which has been vital in ‘powering’ our planet.

3. A Star’s Habitable Zone

Planet hunters and the media have made a major issue out of the concept of the ‘Goldilocks Zone.’ This is the area around a Sun where a planet is not too close, nor too far away. It is an important aspect of the potential for development of life on a planet, but it is only one factor of many. For Earth, we are resting in the orbit that is just right.

4. Moon

It’s hard to overstate the importance of the Moon for the development of life on Earth. First, the Moon was likely formed in a collision when a small planet-sized object hit Earth and tilted our axis (more on this later.) In addition, the Moon has slowed the Earth’s rotation down (more on this later,) and helped enhance the tidal movement of the Earth’s oceans. The Moon has played an important role in human activity, but just as an important role for all our planet’s species.

5. Size of the Planet

Again, size matters. If a planet is too big and the gravity will inhibit the formation of larger, more complex molecular organic structures. Too small and there can be no atmosphere. Earth is in the zone.

6. Axial Tilt

If Earth’s axis was perpendicular to the plane of the solar system the Sun would heat up the equator creating a zone too hot for most life forms. The poles would have minimal solar heating and would be extremely cold. In between would be the combat zone between hot and cold. Constant violent storms and wind would batter the mid-latitudes.

The tilt of the Earth causes solar heating to warm one hemisphere and allows the other to cool down. Every six months the warm/cool cycle swaps hemispheres. This creates storm systems in both hemispheres, but they act to distribute the warmth more evenly. The tilt of Earth’s axis is almost perfect for nurturing life.

7. Length of Day (spin)

We take the 24 hour day for granted. We shouldn’t. Last year Takanori Sasaki, a planetary scientist with Kyoto University, pointed out that the Earth originally spun so fast that its ‘day’ was only four hours long. Multicellular life didn’t develop on Earth until the day was 23 hours long. It’s is not clear at what point a planet’s rotation makes it habitable, but it seems obvious that a planet’s spin is a factor in the possibility of life formation.

8. Atmosphere

It may be obvious that an atmosphere is required for the development of life, but there are qualities to an atmosphere that are also required. The atmosphere cannot be too thick or too thin. It has to consist of an oxidizer, such as oxygen, to promote chemical reactions in cell structures. There is more to Earth’s air than just air.

9. Liquid Water

Water is necessary for all life that we are aware of, even though it is more important to some species than others. Liquid water is even more important to life than water vapor or ice. It is not an accident that the development of life happened on a planet where 71% of the surface is covered with liquid water.

10. Continent to Ocean Ratio

It’s not obvious, but life on Earth has been helped by the ratio of land to ocean. Land tends to have more temperature variance than the oceans between summer and winter. Land that is not covered in ice or vegetation absorbs much more heat in the summer. If most of our planet consisted of continents, the temperature change from summer to winter would be more dramatic, and less friendly to life.

Earth is Unique, Not Rare

Life on Earth was not an accident, nor is it divine. The conditions that led to the development of life here must exist on millions of planets, but there are an estimated 100 billion planets in the Milky Way Galaxy alone. We are unique, but we cannot be alone. Give life an opportunity and it will seize it.

Center of the Milky Way: Update

20 Tuesday Feb 2018

Posted by in Astronomy, Exploration, Generational, NASA, Photography, Science, Space, US Space Program

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During the history of humankind, we have looked up and stared at the center of our galaxy. Most of that time we created stories about it, but now we know some of the facts. If you’re not a space geek, astronomer, or science nut, you may not know what new information has been discovered about the center of the Milky Way. A lot of information has been learned in the course of our lifetime, even if you are only 16 years old.

ESO image Milky Way

The Milky Way Galaxy…as it was 26,000 years ago

Dust in the Wind

To see the Milky Way Galaxy requires getting away from bright city lights on a clear night. It looks like a faint cloud running across the sky at an odd angle. What a person sees is light that has traveled from the center of our galaxy for about 26,000 years. Some of those stars are gone, and new stars have formed.

What you may not know is the dim light coming from the central bulge at the center would be brighter than the full Moon if it weren’t for space dust. Near the center of the Milky Way are over ten million stars. If there were no dust we would just see a dazzling glow from the central bulge.

The Story of Black Holes

Our understanding of the Milky Way has coincided with our awareness and understanding of black holes in space. The idea of a black hole was first suggested in a letter by John Michell published in November 1784. The work of Albert Einstein on general relativity led to theoretical work confirming the mathematical possibility of black holes during the first half of the 20th century.

However, the first prospective black hole wasn’t discovered until 1971. At this point, no one suspected that the centers of all galaxies were black holes. It would be 2002 before Max Planck Institute for Extraterrestrial Physics in Germany would produce evidence that a black hole was at the center of the Milky Way Galaxy.

What You Can’t See

The problems with determining a potential black hole are that, 1) as mentioned before, there is too much dust between Earth and the center of the Milky Way galaxy and, 2) a black hole doesn’t emit light. The first problem is solvable by using different wavelengths of radiation other than visible light. Gamma, infrared, and radio waves pass through space dust and allow astronomers to see their source.

The second problem in revealing a black hole is not what they are, but what they do. What black holes do best is produce the pull of gravity. Their gravitational effect is so strong that stars orbit black holes…before they are eaten by it. All astronomers had to do is find an invisible point that stars are orbiting.

Really, Really Fast Stars

It wasn’t as easy as it sounds, but they did it. What is now known as the supermassive black hole called Sagittarius A is at the center of our galaxy. A close group of stars orbit this invisible point at incredible speeds. Astronomers estimate the size of the black hole is big enough to encompass our Sun and extend almost to the orbit of Mercury.

One of the orbiting stars known as S2 comes only as close to Sagittarius A as four times the distance of Neptune is from our Sun. Despite that distance, S2 reaches speeds of 5000 km/s (11 million mph) as it swoops by Sagittarius A and heads back out in a highly elliptical orbit. S2’s orbit takes less than 16 years to make one complete orbit. S2 will make it’s next closest approach in a few months….well, it actually will have happened 26,000 years ago.