Questions from an astronomy hobbyist

After watching the excellent BBC series The Planets, I realized that I know little to nothing about how we actually get rockets off the ground and into space in order for them to explore our solar system. That is probably the case for most people; they're content just to watch the marvel of space travel without understanding it. And I agree--it is wondrous to watch rockets take off, escape the pull of gravity, move into orbit around the earth, and even to watch booster rockets return to their launch pads as was the case with one of the SpaceX missions in 2019 (https://youtu.be/HVqWEoyiaBA). I haven't experienced the need to understand some of what is actually going on, until now. Because I have so many questions; you can't watch programs like The Planets and not have questions. For example, why are planets round in shape, rather than rectangular or octagonal? The answer is gravity. If you want the full answer, google this question and read some of the links that are returned. As it turns out, gravity is the answer to many of the questions about what has gone on and what goes on in the solar system--e.g. the formation of the planets. So what is gravity? My husband smiles when I ask this question; he studied biophysics in college and has a good background in math and physics. There is no simple answer. He reminds me that astronomers and scientists have been studying gravity forever, and will probably still be studying it a century from now. As Wikipedia states:
Attempts to develop a theory of gravity consistent with quantum mechanics, a quantum gravity theory, which would allow gravity to be united in a common mathematical framework (a theory of everything) with the other three fundamental interactions of physics, are a current area of research. 

So, for those of you who understand much more than I do in this field, you'll have to pardon my ignorance. These are my questions listed below, and I'm well on my way to reading about each of them, albeit, reading the articles about them written for lay people. My understanding of the complicated math and physics necessary to understand all of this ended when I was in my second year of college (I hit the math wall when we began to study the derivatives of trigonometric functions). So my interest in astronomy and cosmology is purely that of a hobbyist.

• What are the different kinds of rockets?
• What powers a booster rocket?
• What powers main engine rockets?
• Where are booster and main rockets manufactured?
• Where is the fuel manufactured?
• There is solid fuel and liquid fuel--which ones are used in the different types of rockets?
• Why are nuclear reactors not used to power rockets?
• What keeps rockets going in deep space; why don't they use up their fuel quickly?
• Why do spaceships go into orbit? To save fuel? 
• How did the SpaceX booster rockets manage to get back to earth? Most of the time the booster rockets end up in the oceans and are retrieved by ships for reuse at future launches.
• What is a gravitational slingshot (gravity assist)?
• What is tidal force? (this played a huge role in the formation of the planets)

These are just some of the questions I have, and am currently exploring online in order to find answers that I can understand as a layperson. NASA itself has a very good website that provides a lot of useful information: https://www.nasa.gov/ , and there are other very good websites for astronomy hobbysists as well. 

After seeing the movie Interstellar in 2014, my interest in our universe really took off, if for no other reason than that I wanted to understand some of the concepts brought up in that movie (tesseracts, for example). I bought the book The Science of Interstellar, written by Kip Thorne, and read it carefully. But prior to that, my interest was already piqued by many of the astronomy lectures sponsored by the University of Oslo's Science Library when I worked there as a consultant from 2010 to 2013. There was and is a healthy interest in astronomy and cosmology on this campus, and it was reflected in the choice of invited speakers. And if I think back even further, to when I was a pre-teenager and a teenager, I was already interested in science fiction, reading authors like Ray Bradbury, Madeleine L' Engle, Isaac Asimov, C.S. Lewis, Ira Levin, and others. So the table was set many years ago. At least I know how I am going to use some of my time when I retire; I plan on visiting Cape Canaveral in Florida again (this time I'll appreciate it more), as well as at least one of the astronomical observatories in the USA as well as one here in Norway (not far from Oslo). As one of my former university professors wrote to me recently, 'you'll definitely have no problem keeping yourself intellectually occupied'. I think he's right.

In praise of NASA

I've been watching the BBC series The Planets, narrated by professor Brian Cox. It's an amazing and breathtakingly beautiful series, and I highly recommend it. So far I've seen the following episodes:

• Life Beyond the Sun--Saturn
• Into the Darkness--Ice Worlds, which covers Uranus, Neptune, the former planet Pluto and the Kuiper Belt
• A Moment in the Sun--The Terrestrial Planets, which covers Mercury, Venus, and Mars and discusses them comparatively with Earth

The final two episodes deal with Jupiter, Earth and Mars, and I'm looking forward to seeing them. 

Besides the wonder inspired by Cox's fascinating presentation of the planets in our solar system, I am in awe of all that the National Aeronautics and Space Administration (NASA) has accomplished since they started their space exploration program in 1958. Founded by President Dwight Eisenhower, this independent agency of the US federal government has delivered time and again, exploring the far reaches of our solar system and uncovering the secrets of the planets and the moons that orbit them. 

But it is the daily lives of the NASA employees that interest me as well--the astronauts, astronomers, cosmologists, technicians, engineers, computer scientists, biologists, geologists--the team of scientists who work together to bring about the success of each space mission. There have been catastrophic failures from which they have learned, and moved on from. But the successes are brilliant and breathtaking, and I love watching the control room explode into joy and relief when a mission has been successful--when pictures are received from millions of miles away from Earth, when a spacecraft lands and begins to move about a planet's surface, or just when the rocket carrying these probes into space takes off successfully. When I think about what NASA has accomplished--the engineering feats necessary to land a spacecraft/probe on distant planets, or to orbit them for long periods of time--I am impressed with the attention to the minutest detail that has facilitated the gorgeous pictures taken by cameras that survive the harshest atmospheres and conditions. Because it is that attention to detail that defines science and real scientists. It is why a scientific career is not for everyone, but for those of us who have worked in science, we can attest to the fact that the success of any experiment lies in the well-planned details. The basic knowledge has to be there first, along with creativity and futuristic visions, and the combination of these leads to the discovery of new data and realities that further our knowledge and expand our ways of looking at things. 

I am proud too of the politicians who envisioned this program for the USA. Despite the fact that it was part of our space race with the Russians during the Cold War era, it grew far beyond that into true scientific exploration. Little did the politicians know when NASA was established that men would actually walk on the moon, that motorized vehicles would traverse the surface of Mars, that spacecraft would travel out into the Kuiper Belt at the edge of our solar system. It boggles the mind, truly, to see what has been accomplished. Yes, it has been expensive, and there are those who would argue unnecessarily expensive, that the money could have been better spent on other things. Perhaps. But when I watch the public response to rocket lift-offs, to moon landings, to Mars landings, it tells me that it is worth the money. Because we are learning all the time, we are doing what man/woman is meant to do--explore his/her surroundings, question his/her origins, and ponder the meaning of life in general and his/her life in particular, on the one planet in our solar system that supports life as we know it. We are blessed each and every day to be able to wake up on a planet that provides all of the conditions we need to live. That by itself is awe-and -gratitude inspiring. 

My sci-fi heart and the death of Oppy

Who knew, who ever knows, how one will react to different news stories? The demise of the Mars Rover Opportunity after 15 years spent on the Red Planet touched me in a way I didn't realize was possible. Perhaps it was its last message to its scientist caretakers here on earth at NASA that got to me: "My battery is low and it's getting dark". My heart went out to 'Oppy'. As I wrote on Facebook--"its demise is strangely poignant". For me and for many others, it is. I realize that I'm talking about a robot, but for some reason, the fact that it could relay that message to the scientists told me that in some strange way, it 'knew' that it was dying, as it knew that it was alive. And that's enough for me. Have I read and seen too many sci-fi books and movies? Perhaps. But NASA understands us and has made it possible for those who want to send a postcard in memory of Oppy, to do so. I sent a postcard that read: "Thank you for 15 years of service, Oppy. Rest in peace on the Red Planet. Maybe one day some of us will join you there".

Here is the link if you want to do the same:   https://mars.nasa.gov/participate/postcard/opportunity-rover/#Step-1, and a link to the original article I read this morning: https://abc7ny.com/5137455/?fbclid=IwAR05vvlqMPgZDiUNPi5WbMAQ7YRC4TU2xVvOV37Z5kEoWWTrTz_dhypHIDU

There are many of us who will miss Oppy. Thank you NASA, for all the great work you did keeping Oppy up and running, and for the important and necessary work you do, everyday. Your work inspires those of us who are curious, adventurous, interested in space exploration, and interested in science.

Watching the Orion liftoff

If you want to watch live coverage of the Orion liftoff, check out the following links:

http://www.nasa.gov/multimedia/nasatv/index.html#.VIBDJ9LF8rV

http://www.ustream.tv/nasahdtv

The liftoff has already been delayed several times due to wind, core engine temperature readings and a fuel and drain valve that did not close. Let's hope there is a launch today within the time window remaining.

For those of you who don't follow NASA's activities, Orion is an unmanned flight that will launch atop a Delta IV heavy rocket. It will be a two-orbit, four-hour flight followed by landing in the Pacific Ocean. The launch will be at Cape Canaveral in Florida, and will be a flight test of the systems that are most critical to safety. The ultimate and future goal is to take astronauts further into space than they've ever gone before.