Which giant planet formed first?
Short answer: Jupiter
Long answer: Still Jupiter, but let’s dive in and take a more detailed look.
Image Credit: NASA
Birth of a Gas Giant
A long time ago in a solar system very near you, just 1 or 2 AU past the snow line, enough surrounding planetesimals were accreted to become an Earth-like body containing about ten (10) Earth masses of metal and rock. This, in turn, gave this massive body enough gravitational attraction to pull vast amounts of hydrogen, helium and ices near its orbit, creating the first planet in our solar system: Jupiter. Impacts from the infalling gases and ices heated Jupiter up, so much so that for a short time, it outshown the protosun, if viewed from equal distances. Jupiter lacked the total mass to become a star, needing to be seventy-five (75) times more massive to achieve the necessary compression and heat in its core to sustain fusion.
This week’s discussion topic will attempt to answer the question:
Suppose your Newtonian reflector has a mirror with a diameter of 20 cm and a focal length of 2 m. What magnification do you get with eyepieces whose focal lengths are: a. 9 mm, b. 20 mm, and c. 55 mm?
From my textbook:
The magnification of a reflecting telescope is equal to the focal length of the primary mirror divided by the focal length of the eyepiece lens:
Magnification = Focal Length of Primary / Focal Length of Eyepiece
In the question stated above, the three different eyepieces will result in the following magnifications:
|2000 mm / 9 mm = 222X
|2000 mm / 20 mm = 100X
|2000 mm / 55 mm = 36X
My second post in my series of weekly discussion topics for my Introduction to Astronomy online class. Last week I got up close and personal with the many sides of the Moon. This week I take a closer look at the other blue planet in our solar system and how we discovered it without observing it first.
The image is among the last full disk photos that Voyager 2 took before beginning its endless journey into interstellar space. (NASA Jan 1996)
Why was the discovery of Neptune a major confirmation of Newton’s universal law of gravitation?
Before Newton, astronomy relied on observational data from which mathematical formulae and equations were created. Newton pioneered an approach which allowed mathematicians to extrapolate and predict the movement of objects using three assumptions, now commonly known as his laws of motion. Together with his formula for gravitational force, Newton transformed Kepler’s three laws to predict orbits of comets and other solar system objects. He further formulated a mathematical model, known as the Law of Universal Gravitation, that describes the behavior of the gravitational force that keeps the planets in their orbits. (Comins, 2015, p. 42-44)
Image credit Tony Wayne Jan 2004
Another semester is upon me and my continuing pursuit of a degree. This fall I’m seeking my science lab course credit so I decided to enroll in something I can easily get excited about: Astronomy
The following post begins a series of weekly discussion topics I’m required to choose and post to my online Introduction to Astronomy class discussion board. Since the formatting is very similar to that employed here at my blog, I’ll draft and publish my topics here as well. Feel free to comment or ask questions. I’ll do my best to answer or at least point you in the right direction.
Near and Far, Light and Dark; the Many Sides of Our Moon
Yin and yang can be thought of as complementary (rather than opposing) forces that interact to form a dynamic system in which the whole is greater than the assembled parts. Everything has both yin and yang aspects (for instance, shadow cannot exist without light).
The moon’s rotation (axial spin) matches its revolution (orbit), also known as a synchronous rotation or tidally locked. This results in the same side, the near side, always facing towards Earth. Until 1959, humans had no idea what the far side of the moon looked like. Continue reading
I knew going into Friday I would have a very long day ahead of me. I had errands I needed to run first thing in the morning, so I planned to be late to work. I stayed up past my usual bedtime, keeping my husband company. We watched the inaugural episode of the new Amazon series “The Tick”, which is a remake of the two other Tick series from the 90s and 00s. We also watched the latest episode of “Salvation,” which is shaping up nicely. Not enough science, but plenty of political and personal interactions to keep the layman interested.
I forgot to turn off my alarm but didn’t mind getting up at my normal time of half past five. I did a few minutes of exercise on our elliptical and ran myself through the shower. I avoided logging in to work so I wouldn’t distract myself from the errands I needed to complete. In honor of Monday’s total solar eclipse, I wore my commemorative T-shirt produced by the Astronomical Society of Kansas City. I made sure to grab my ASKC name badge and place it in my car as I would need it for the final event on my Friday schedule.
At half past seven, I left and headed north, with a quick side trip through the car wash, which was surprisingly unbusy so early in the morning. I continued north through Lansing and most of Leavenworth until I reached the old county courthouse. I parked in the Justice Center’s parking lot and serendipitously ran into one of my book club friends on her way to work.
I walked the block back to the old courthouse and grabbed number 45 from the dispenser with about ten minutes wait time before the Treasurer’s office opened. I decided to pay the taxes and fees for my newest vehicle the old-fashioned way – in person and with a handwritten check. The number displayed as being served was 41 so I knew I wouldn’t have long to wait. I made myself comfortable on the old pew-like wooden bench and continued listening to the Dreamsnake audiobook I’d recently checked out via Hoopla.
Posted in Astronomy, Epic Fantasy, Fantasy, Jupiter, Moon, Musings, Saturn, Seasons, Summer
Tagged amateur astronomy, college, crescent moon, education, epic fantasy, fantasy, Jupiter, Saturn, science, TGIF, Tolkien
Tonight is opening night for Seattle Opera’s production of Madame Butterfly. My daughter, Rachelle, is once again a member of the cast. She appears third from the left in both photos below.
[ Philip Newton photo ]
[ Philip Newton photo ]
Earlier this year, Rachelle was also a member of the cast of Sarasota Opera’s production of Madame Butterfly
. So she really has done this show from coast to coast.
Rachelle as Kate Pinkerton
Now I’m wishing I was in Seattle so I could attend opening night.
Break a leg!
Modesitt is preaching to my choir again:
… minorities, women, and others affected by the history and legacy of racial and gender discrimination. They’re tired of endlessly waiting for equality, and with ethnic, racial, and gender discrimination continuing, those feeling that discrimination is continuing are also getting angrier and angrier.
The Anger Problem, published 7/25/2017 http://www.lemodesittjr.com/2017/07/25/the-anger-problem/
Also read this morning, and a blog post I also commented upon:
If we had maximum democracy every registered voter would vote on every bill without using representatives. Since we have a representative democracy, our elected proxies should vote the way we want. Often, this doesn’t happen because they work for a minority rather than the majority. This is called an oligarchy, and since our oligarchs are rich, we call our form of oligarchy a plutocracy. I guess that’s fancier label than Rule by Billionaires.
We Need More Democracy
I’m just all kinds of warm and fuzzy today but I blame that on the hot humid Kansas summer.