Category Archives: Mac’s Notebook

There May Be a New Ninth Planet (Sorry Pluto)

It was long a well known truth that our solar system had nine planets, until scientists realized that Pluto was, in fact, a dwarf planet. Dwarf planets are planetoids which meet two of the criteria for a planet — being an object large enough to crush itself into a sphere, but not large enough to cause thermonuclear fission — but has failed to clear its domain of space debris. For a few years after our conception of the solar system was shocked, all was well and stable, but then astronomers started noticing a strange attribute of five objects in the far reaches of our universe: they all had strangely eccentric — meaning elliptical instead of circular — orbits which aligned into a plane, and they all orbited in the same direction.

The Pair of Scientists Searching for the Planet
The Pair of Scientists Searching for the Planet

Mike Brown, an astronomer at the California Institute of Technology and the leader of the team who discovered these objects, came to the conclusion that there was less than a one percent chance that all five orbits would align without some outside force influencing them. To solve the mystery, he enlisted the help of Theoretical Astrophysicist Konstantin Batygin.

The answer they came up with was that there must be some massive object in the solar system that affects their orbits. The thing is, when they started to look at possible orbital paths that would allow them to interact and cause that pattern, they realized that this hypothetical Planet Nine would only be close enough to these five objects every 50,000 years or so. If this is the case, then Planet Nine would have to be truly huge — at least ten times the size of Earth.

The Telescope Being Used to Find Planet Nine
The Telescope Being Used to Find Planet Nine

While the scientific community has generally been skeptical about claims to have found a new planet in the solar system, for obvious reasons, it seems like this time is different. This time, the math actually checks out, and it points astronomers to the supposed location of this new planet. As of now, the two scientists are using a telescope named Subaru to scan swathes of the sky, but it could still take over five years for them to scan all of the potential ninth planet’s expected location. Keep an eye on your favorite source of science news, and wait to see if this pans out!

Juno enters the orbit of Jupiter after over four years in space.

A digital representation of Juno’s view as it approached Jupiter

Late in the evening of July 4th, 2016, NASA’s probe Juno finished its journey to Jupiter, the fifth planet in our solar system, and entered orbit around it.

The probe was launched back on August 5th, 2011, as part of the New Frontiers program, which previously sent the New Horizons space probe to Pluto in 2006. The objective of the unmanned mission is to investigate Jupiter and report back with previously unknown information about Jupiter’s physical make up. This information will help scientists understand how Jupiter, and by extension the rest of the planets in the solar system formed. It is planned to spend the next twenty months orbiting Jupiter, completing 37 full orbits, before allowing its orbit to decay and falling into the gas giant. It will be transmitting information to NASA for this entire duration.

The last photo sent from Juno before powering down nonessential instruments to enter orbit.
The last photo sent from Juno before powering down nonessential instruments to enter orbit.

When news of the successful orbit reached NASA the mood was one of jubilation, with administrator Charles Borden saying Independence Day always is something to celebrate, but today we can add to America’s birthday another reason to cheer — Juno is at Jupiter. And what is more American than a NASA mission going boldly where no spacecraft has gone before? With Juno, we will investigate the unknowns of Jupiter’s massive radiation belts to delve deep into not only the planet’s interior, but into how Jupiter was born and how our entire solar system evolved.”

The name of the probe comes from Greco-Roman mythology, specifically a story where Juno, wife of Jupiter, penetrates swirling clouds surrounding him to find his true nature. The Juno probe has the same objective, although in a slightly different context.

One (More) Small Step: Orion Spacecraft Set to Launch

NASA’s-Orion-Spacecraft-2-798x350When NASA launches its brand-new Orion spacecraft later this year, it is also launching what it hopes will be a new era of human spaceflight. It will be a test flight, but the ultimate goal of the Orion project is to send humans further into space than the moon for the first time ever.

The test flight is scheduled for December. NASA will launch Orion from Florida. From there, it will orbit the Earth twice before landing in the Pacific Ocean. Although the point of Orion is to carry astronauts into space, this test will be unmanned. Scientists and engineers want to see how the spacecraft performs, especially Orion’s life support systems and the systems that connect Orion to the rocket.

Image converted using ImgCvtThink of future space launches as having two main parts. Orion is the module that will carry astronauts. Once the astronauts have completed their mission, Orion also has the capacity to safely reenter the atmosphere. The Space Launch System, or SLS, is the system of rockets that will lift it into space. The SLS is still being developed. For the December test, Orion will be launched using a type of rocket that already exists.

The goal of the Orion program is to first capture an asteroid that has been towed into lunar orbit, and eventually take humans to Mars, which NASA projects may happen by 2025.

Orion is a revival of the United States’ largely dormant space program that should see humanity go further than it ever has. So you can bet that when Orion takes off in December, all eyes will be on it.

OrionWhat’s in a Name?
Orion is one of the most famous constellations in the night sky. In the epic Greek adventure by Homer, The Odyssey, Orion was a hunter who, upon his death, was made into a constellation.

Fun Facts:

  • Orion’s first test flight will take it 3600 miles above the Earth, 15 times the distance of the International Space Station.
  • Orion’s test flight will use the Delta IV Heavy, but when Orion is actually used to transport humans, it will change to the more powerful Space Launch System.
  • When Orion reenters the atmosphere, it will be moving at over 20,000 miles per hour, which will cause the exterior of the spacecraft to heat up to 4,000 degrees Fahrenheit.

9. How to Think Like a Scientist – Astro Scale

Astronomy scale distances
Illustrators and designers have struggled with the best way to represent the Solar System graphically.

Imagine holding an automobile in your hand. It’s easy, just pick up a matchbox car. Matchbox cars have lots of features of a real car, just shrunk down. Scientists call this a “scale model.” Model because it is not a real car, and scale because all the parts are shrunk down by the same amount. A Matchbox car is scaled by about 1:64, meaning a real car is 64 times bigger than the toy.

thunderbird_matchboxA Barbie doll is also a scale model, but it can’t fit in the matchbox car because it is scaled differently. Barbie dolls are scaled by about 1:6. A real girl is about 6 times bigger than the doll. Barbie is over 10 times bigger than the matchbox car. For Barbie to drive a Matchbox car, the car would have to be about the size of a football, or she would have to be shrunk down to the size of penny.

Thinking like a scientist means trying to describe reality to make future predictions. A very effective way to do this is by using models. They help scientists understand things that are too humungously big (or small) or too freakazoidically far away to make sense of. But remember, for a model to make sense all objects in the model must be at the same scale. Barbies and Matchbox cars are both scale models, just not to the same scale.

Models are often mathematical, but can also be made of die-cast metal and plastic. The more accurate the model and the more closely it describes reality, the better. Some toy cars just roll. Others have working doors and make noise.

Definitely Not to Scale: Here is a real picture of a basketball and a real picture of a pea. Presented together, the pictures suggest something that anyone who has played basketball and eaten their vegetables knows to be untrue -- that they are roughly the same size. You'll notice that in scientific pictures, a ruler or some other object of known size is often included in the frame. Otherwise, it's very hard to know from a photograph how big something really is.
Definitely Not to Scale: Here is a real picture of a basketball and a real picture of a pea. Presented together, the pictures suggest something that anyone who has played basketball and eaten their vegetables knows to be untrue — that they are roughly the same size. You’ll notice that in scientific pictures, a ruler or some other object of known size is often included in the frame. Otherwise, it’s very hard to know from a photograph how big something really is. But of course, a ruler wouldn’t help much with objects of planetary size.

Consider our solar system: Our nearest star, the Sun, is big. Really big. 865,000 miles wide. 110 times wider than the Earth. But what does that mean? Let’s build a model.

Imagine the Sun was scaled down to the size of a basketball, how big would the Earth be? The size of a baseball? Of a golf ball? No. More like the size of a pea. A basketball and a pea.

To Scale, Sort of: In this picture, our basketball and our pea are presented in proper size relative to one another. Case closed? Not quite. Since this article is talking about models and has been discussing the earth and the sun in terms of peas and basketballs, this picture suggests that this is how the earth and sun would look together. It is, sort of, but for the model to work the pea would need to be much, much further away from the basketball, 94 times as far away, in fact. Many of the Solar System maps you see on posters show the planets and sun much closer together than they really are, even when the relative size differences are factored in.
To Scale, Sort of: In this picture, our basketball and our pea are presented in proper size relative to one another. Case closed? Not quite. Since this article is talking about models and has been discussing the earth and the sun in terms of peas and basketballs, this picture suggests that this is how the earth and sun would look together. It is, sort of, but for the model to work the pea would need to be much, much further away from the basketball, 94 times as far away, in fact. Many of the Solar System maps you see on posters show the planets and sun much closer together than they really are, even when the size differences are factored in.

The Sun is far away from us, 93 million miles away. But what does that mean? If the Sun was a basketball in the hoop of one basket at a basketball court, the Earth would be a pea at the other basket 94 feet away.

If we keep going, a quarter-mile away from the basketball Sun is a golf ball named Jupiter. A half-mile mile away is a pingpong ball called Saturn. Three-quarters of a miles away is a walnut named Neptune. The NASA spaceship Voyager 1 (the furthest out manmade object ever) is a speck of dust about a mile away from the basketball.

Perfect: We've created the most accurate picture yet! Only problem, it may be the world's most boring poster. (The yellow arrow helps you find the pea in this expansive field of blue. It's there - we promise). There is a reason they call it space.
Perfect: We’ve created the most accurate picture yet! Only problem, it may be the world’s most boring poster. (The yellow arrow helps you find the pea in this expansive field of blue. It’s there – we promise). There is a reason they call it space.
So the Sun is really big and far away But the other stars are so much farther away I can barely describe it. The Sun is just one of many stars in our Milky Way galaxy. One of the next closest stars is Alpha Centari over 26 trillion miles (4 light years away). But what does that mean? Let’s expand the model.

Suppose the Sun was a basketball was at Disneyworld, Orlando Florida, at the Space Mountain ride. At that scale, Alpha Centari would be another basketball at Space Mountain in Disneyland in Pasedena, California 2,500 miles away! And that’s just the closest star. Other stars in our galaxy are much farther away.

To make sense of them, we would have to change the scale of our model again. Shrink the Sun down to the size of a pea. Earth is the size of a poppy seed. Alpha Centauri is now a pea only a mile away still in Orlando Florida. Other stars in our Milky Way galaxy are peas in California. And that’s just our galaxy.

The next closest galaxy to the Milky Way is Andromeda. The Andromeda galaxy is 2 million light years away. What does that mean? We need another scale!

Stars are really far away. Musician George Hrab explained it best in his classic song, “Far.”

“I sense all the explosions going off inside your brain
As your mind gets blown by what I just did explain
Sorry if my words might drive you all insane
But that’s what happens when precision is your middle name

This stuff is far, [it’s really far] this stuff is far far far away
We’re talkin’ far, [like über far] you can’t get there by car in a day”


Talking Like a Scientist: Magnitude
Scientists have an easy tool to help make sense of really big numbers and make comparisons.. When looking at any two numbers, scientists count the number of digits in each number. For instance, with Barbie’s scale factor (the number of times it is shrunk), 64 has two digits a 6 and a 4. If two scale factors have the same number of digits (like 64 and 11), then scientists say they are of the same order of magnitude. If one scale has 2 digits and the other has 1 digits (like 64 and 6), the 64 is considered to be an order of magnitude smaller. Barbie dolls are an order of magnitude larger than a matchbox car.

Venus is closer to the Sun than Earth, but they are the same order of magnitude away. Andromeda is 6 orders of magnitude farther away from Earth than Alpha Centari.


References:

http://en.wikipedia.org/wiki/Matchbox_(brand)

http://www.eharm.net/night_sky_guide/distance_and_time/distance_and_time.html

Song, “Far” by George Hrab from the album Trebuchet.

Song “The Sun is a Mass of Incandescent Gas” – by They Might Be Giants, from the album Severe Tire Damage.

365DaysofAstronomy.org