Jovian planets always interested me. The term “Jovian” is naturally everyone’s first guess – derived from the Latin root, Iovis, or Jovis. It’s a 3rd declension, genitive singular noun, so any classics nerds should know that it very specifically translates to OF Jupiter.
I don’t know, I just find it interesting that an entire class of planets was named after one. Speaking of that one, Jupiter in particular has always been of interest. It’s the giant of our system…a stormy, gaseous planet. There’s so much more though. The violent, 300mph winds, raging storms visible as a large spot lasting for centuries, and extremely powerful lightning…There’s so much exciting weather to explore with Jupiter!
One more calming phenomenon I find is the aurora, which we know on Earth to be a beautiful luminescence near our pole. Well, sure enough, Jupiter has auroras. Kind of makes sense, but we normally wouldn’t associate such a pretty picture with a planet that tends to have key word searches like storms and violent. They occur at both poles on Jupiter and are constantly occurring!
The astronomical symbols of the solar system. NASA.
When looking at our solar system, it is pretty easy to notice one thing that separates Earth from the other planets with which we share a star. Namely, Earth is the only planet not named after a Roman deity. You have Mercury, Venus, Mars, Jupiter, Saturn, Neptune, Uranus, and even Pluto! So where does “Earth” come from? Well, LiveScience has half an answer.
The word “earth” comes from from the Anglo-Saxon “erde” or “erda,” meaning literally ground. Eventually, English turned the word into “eorthe”, and then the “earth” we know and use today. However, it is unknown how the word came to represent the whole planet as well.
Also, how we denote Earth has had a number of changes over the generations. We know typically symbolize Earth with either 🜨 or ♁. However, the earliest civilizations had yet to understand Earth as a sphere, and used symbols representing flatness, like the Sumerian 𒆠, which started out meaning something like a floor. More about earth symbols (including cool alchemy stuff) here!
Strict Aristotelian cosmology follows that all bodies are made of the four elements: earth, water, air, and fire. These four exist in the terrestrial realm and the stars exist in the celestial realm. A fifth element, aether, exists there and that is what heavenly bodies are composed of. Aristotle provided the basics of the physics that would be proven about the universe without any qualitative information. For Aristotle, the universe is not infinite in size and could be measured. Besides the up-down, back-forward, and left-right movement, there is an eternal time frame that moves in circular motion swiftly encompassing the bodies of the fundamental elements and the objects they compose. Hipparchus used two motion orbit to calculate the precession periods caused by the sidereal and solar year. He used the basis of Aristotle’s proof that the universe is a circle and can be measured using geometry with the understanding that the circumference would be twenty- four hours, the earth’s orbit. On the other hand, Ptolemy preferred the simple single model. Ptolemy was able to create models of the planets based on these descriptions of the physical universe. His calculations took into consideration that there did not exist any vacuums between the spheres so all measurements were consecutive. He enlarged Aristotle’s ideas and made the correction that the equant, the circle proposed to surround the earth, is off-center. It still would have the constant speed and angular motion that it was believed to have. The use of Aristotle’s cosmology lies in its common-sense appeal that wasn’t proven wrong for over a thousand years.
Climate change is predominantly caused by the greenhouse effect, which is when gases in our atmosphere prevent heat from the sun from escaping the Earth. As greenhouse gasses continue to be added to our atmosphere (primarily by burning fossil fuels), the greenhouse effect becomes more severe, allowing less and less heat to escape from our atmosphere, causing global warming. The earth’s temperature has fluxuated over time, but CO2 levels on Earth today have not been so high in hundreds of thousands of years. Global warming impacts our weather, our health, our oceans, our crops, and much more. We can combat climate change by finding cleaner, more renewable forms of generating energy. Climate change is especially relevant today, as our president continues to deny its existence. In order to create change, we need someone in charge who will listen to our scientists and do what needs to be done to preserve the health of ourselves and our environment.
A short video in which you can see solar flares and solar prominences occurring along the Sun’s surface.
I obviously can’t speak for anyone
else, but I whole-heartedly believed that the beautiful loops of material that
we sometimes see images and videos of on the Sun were included in the term ‘solar
flare.’ As I looked into it, I came to find that solar flares and solar
prominences (the ‘loops’) are in fact separate things.
Solar flares are sudden
flashes of brightness sometimes observable on the surface of the Sun. They occur
when an area of the plasma of the Sun interacts with accelerated charged particles,
and the plasma is heated to tens of millions of Kelvin while ions are accelerated
to nearly light speed. Flares happen in active regions (near sunspots) and
occur when magnetic energy stored in the Sun’s corona is suddenly released.
Flares produce electromagnetic radiation, but only some of the energy released
is within the range of visible light, meaning that the majority of a solar
flare is not actually visible to the naked eye. X-rays and UV rays from solar
flares can have effects on Earth’s upper atmosphere, while radio emissions can
disrupt Earth’s long-range communications (e.g. radar devices that depend on
radio frequencies).
Solar prominences, on
the other hand, are essentially loops of relatively cool plasma that form on
the Sun’s surface and extend outward into the corona. They form in the magnetic
fields generated by sunspots. Prominences can reach up to hundreds of thousands
of miles into space and persist for several weeks or months. Some prominences
may break apart and result in coronal mass ejections. {A coronal mass ejection
(CME) refers to the release of a large amount of plasma and electromagnetic
radiation from the solar corona into space. They often follow solar flares or
other solar activity and can cause both negative effects (e.g. communications disruptions
as aforementioned in the discussion of solar flares) and positive effects (e.g.
auroras).}
One topic regarding Saturn’s rings that I found extremely interesting was the concept of its Shepherd Moons and how they contribute to the uniformity of the rings. If my understanding and memory are correct, this phenomenon is governed by conservation of energy. Essentially, the moons are on opposite sides of the ring, where the moon that has the farthest distance from the planet is moving slower than the closer moon. That’s because of a bunch of physics formulae that illustrate an inverse relationship between velocity and energy (and velocity and radius). Long story short, an equation similar to the gravitational force equation, E=GMm/2r as well as setting up a system of total mechanical energy E = K + U yields E = 1/2mv^2 – GMm/r and we treat E to thus equal GMm/2r when you simplify it. Also, setting the force of gravity equal to centripetal force yields v^2=GM/r which lends to the mathematical proofs of the above relationships.
Aaaanyway, physics aside, the really interesting part about this is how it regulates Saturn’s ring shape! How is it so picture perfect? Well, it’s been a while since I took physics, but basically, if a particle from the ring were to drift, in the direction closer to Saturn, as it’s getting closer to the shepherd moon, the moon will give it a tug…This is because the moon is going even faster (remember, smaller radius, greater velocity), and thus adds extra energy to that system. Remembering that E has an inverse relationship with velocity, now that it has greater energy, it is of a greater radius and lower velocity…aka, it moved to a position farther away from the planet. The opposite also works, but it’s the slower moon on the outer radius that imposes a drag force, if memory serves. Physics might be a drag and tests might be hard but the way it works is undeniably cool!
The planet Venus is named for the Roman goddess of love and beauty.
It is the second largest terrestrial planet. It is also the second brightest natural object in the sky. Venus’ apparent
magnitude of -3.8 to -4.6 makes it visible on a clear day. Venus’ atmosphere
can be divided into two layers: the cloud bank that covers the entire planet
and the atmosphere below these clouds. The clouds extend from 50 to 80
kilometers over the planet’s surface and are composed primarily of SO2 and
H2SO4. These clouds are so dense that they reflect 60% of the sunlight Venus
receives back into space with an atmospheric density of approximately 480° C.
This makes Venus’ surface the hottest of all of the planets in the solar
system.
Scientists have been able to use the method of radar mapping to
acquire images. Using radar mapping with Venus allows microwave radiation to
pass through the planet’s thick clouds, whereas photography is unable to do so
because of light. The first radar mappings the surface of Venus came via
spacecraft came in 1978 when the Pioneer Venus spacecraft began orbiting the
planet. The surface was made mostly of plains formed by the flow of ancient
lava, with only two highland areas, Ishtar Terra and Aphrodite Terra. These
volcanoes, unlike the ones on Earth were formed from an eruption of all of the
volcano’s lava at once through a single vent. After such an eruption, the lava then
spreads outwardly in a uniform, circular manner. Like the goddess the planet is
named after, Venus is composed of passion and turbulent geological features.
Nuclear fusion is where two nuclei combine resulting in a displacement of energy. The fusion of hydrogen atoms into helium specifically is what powers the energy output of the sun. This can only occur under the most extreme conditions – typically, the positively charged nuclei of two atoms repel each other quite strongly, and so nuclear fusion can only occur under extremely high temperatures and densities. The sun accomplishes these conditions due to gravity and the sun’s incredible mass. Scientists are still working on harnessing the power of nuclear fusion for our own use, but it is extremely difficult to generate enough energy to fuse atoms. Most methods revolve around heating plasma. Magnetic confinement reactors use electromagnets to move the plasma incredibly fast. Inertial confinement reactors use pulsing lasers to heat up fuel pellets until hot enough to fuse. If nuclear fusion energy gets enough funding, it could provide massive amounts of clean and sustainable energy.
Though we do not currently have the means to see directly inside the Earth (or any other planet), we can use clues to make inferences about what may be lying beneath their surfaces. On Earth and the Moon, our most helpful data stems from the analysis of seismic waves, or vibrations that travel along the world’s surface and through its interior after earthquakes. For other terrestrial worlds, we can use other measurements like average density and gravity to determine the distribution of mass in the world’s interior. In this blog post, I will be discussing the three major layers that are present inside the terrestrial worlds: the core, the mantle, and the crust.
The Core: The innermost layer of the terrestrial worlds also has the highest density. It is primarily composed of metals, including iron and nickel. Mercury has a very large core of iron that comprises around 85 percent of its interior. The cores of Earth and Venus are made up of a solid, inner core and a molten outer core. Tectonic activity is also caused by heat in the world’s core.
The Mantle: Thick, rocky, moderate-density mantles surround the cores of the terrestrial planets. They are composed of mostly minerals that contain oxygen, silicon, and other elements. With the exception of Mercury, the mantle makes up a large portion of a terrestrial world’s volume; Earth’s mantle makes up 84 percent of the planet’s total volume.
The Crust: The terrestrial planets have thin crusts composed of low-density rock that make up their outermost layer. The Earth’s crust contains a great assortment of metamorphic, sedimentary, and igneous rocks; however, it makes up less than 1 percent of the planet’s total volume. The crusts of the terrestrial planets were formed through various igneous processes, and they frequently change due to erosion, sedimentation, volcanism, and cratering.
Photographers had known about it for decades, but scientists didn’t get wind of it until 2016. It’s a streak, purple or white, across the night sky. It looks like it could be a type of aurora… but that’s not what it is.
The kind of aurora that we’re familiar with happen when charged particles (electrons and photons) from the sun hit neutral atoms in the Earth’s ionosphere. These collisions excite molecules in our atmosphere, bringing them to higher energy levels. When these charged particles drop down to lower energy states, they release light. This creates the bright streaks that we picture when we think of aurora. The specific colors depends on which gases are being excited. For example, oxygen gives off green and Nitrogen can give off blue or red. In addition, aurora can only be seen near the poles, and are visible every night (with the right viewing conditions).
The new things people were seeing, the purple streaks, do not behave like this. They show up near the equator, and only a few times a year. We also know that they aren’t excited protons, because they show up on equipment that wouldn’t otherwise be able to detect proton wavelengths.
The observers who brought it to researchers’ attention call it Steve, referring to the movie “Over the Hedge.” Scientists decided to turn it into an acronym. Now, the phenomenon is called STEVE, for Strong Thermal Emission Velocity Enhancement.
So we know it’s not aurora. But what is it?
Researchers from the University of Calgary wanted to see if it was a similar mechanism to aurora–if it was from particle interaction in the ionosphere. To figure it out, they analyzed pictures from a STEVE event in 2008. They also looked at data from a satellite called POES-17, which can measure charged particles raining down to the ionosphere. The satellite had no record of charged particles entering the ionosphere while the event was occurring, which means that STEVE happens for different reasons. What those specific reasons are have yet to be determined.
For now, that is the only science out about this event. As of now, the best language researchers have to describe this is “skyglow.” In future studies, they want to find out if the light is coming from the ionosphere, or higher up.
