In this week’s astronomy lab, my students needed to make some simple calculations, mostly involving some arithmetic and a little bit of algebra to convert hours and minutes into decimal hours (for example, 1hr 30min = 1.5 hrs) and some arithmetic. Nothing too complex, but it was nevertheless a major challenge for many of my students, eliciting groans of “I suck at math”, “I’m not a math person”, etc.
I’m sympathetic, to a point. I struggled with math quite a bit as a wee lad, and even as an undergraduate astronomy major in college (don’t tell anyone). But looking back, I realize that the reason I “sucked” at math was because I told myself I sucked at math. Once I decided I no longer sucked at math, I suddenly got better at it.
I watched this happen to a student when faced with the problem of calculating the difference in time. He was struggling with some time calculations and asked me for help. It went something like this (and yes, I’m paraphrasing):
Me: Ok, so you need to figure out the time difference between 1:16 and 1:21. What is it? Student (tired, frustrated): Oh man, I’m just not sure right now. Me: No problem. Let’s imagine you and I are playing blackjack together in Atlantic City— Student: Now you’re talking my language! Me: Cool. So you’re dealt a 7 and a 9. What do you have? Student: 16, a really sucky hand. Me: And the dealer is showing an 8, what do you need to do? Student: This sucks, I have to hit. Me: Yeah, you do, but what do you have to pull in order to make 21 and guarantee you won’t get beat? Student: A 5. Me: Right, so what’s the difference between 1:16 and 1:21 again? Student: Oh geez, of course. Duh!
I got a little lucky here – I didn’t know that the student played blackjack, I just guessed. But mathematically, the problem was the same. The context of the problem seemed to make all the difference. At the blackjack table, he no longer seemed to think he sucked at math and suddenly the problem was a piece of cake.
A lot of math phobia gets swept away when you are presented with problems in a more familiar setting. That’s why I know my students don’t suck at math, or at least not nearly to the degree they think they do. After all, math is hard, but it’s a skill you can learn.
I’ll wrap this up with a video that caught my eye this morning that dispels a lot of the myths, fears, and misconceptions about math. I’m not a genius at math by any means, and I might have to stop and think a little bit more when solving a problem than others. But I don’t suck at it, and neither do you.
I realize that there are no shortageofreviews of last night’s premiere of Cosmos: A Spacetime Odyssey (including one by my good friend Mike Brotherton), but I did have a few thoughts of my own. First and foremost, I loved this show. It was beautiful and poetic, thoughtful and insightful, and firmly made the case that science is the only way to really understand the world and universe we live in. Will I love it as much as Carl Sagan’s original? Maybe, maybe not, and truthfully, I’m ok with either outcome.
Although Sagan is no longer with us, having his protege Neil deGrasse Tyson at the helm of the new Ship of the Imagination is a fitting passing of the torch. And what better way to begin the new voyage than with an homage to Sagan. I couldn’t imagine a more fitting kickoff to this series than to literally begin at the same location Carl did 34 years ago.
But in that time a new audience has grown up that is inundated with even more television channels and production values that far surpass anything Hollywood was capable of producing in 1980. Make no mistake, the production values of the original Cosmos were, in my opinion, absolutely incredible. I truly felt like I was flying through the universe with Carl on his ship. Even though there is no way they could possibly do a poor job with this new production, I was wondering if the new series might go overboard with the use of visual effects, or use them in a way that has, quite frankly, been done to death in other science programs. The answer, to be honest, was a bit of a mixed bag for me.
Cosmos sets out to orient the viewer in much the same way as it originally started out – by describing our place in both in space and in time. The space bit had Tyson and his ship zipping through the Solar System, which was fine until…
To be fair, they didn’t show the Ship zigzaging around the asteroids in hairpin tuns a-la the Millennium Falcon in Star Wars: The Empire Strikes Back; This shot was much more graceful than that, suggesting perhaps a little bit more space between the asteroids. But the truth is that asteroids are already very, very far apart from one another. I personally would have much preferred a setup where the audience thinks they’re about to play cosmic dodge ball, only to discover that the asteroid belt is wide open with nothing in sight, and Tyson actually having to set course to fly by an asteroid in order to glimpse one up close. That might not have been as visually stunning, so it looks like they went for the cool shot instead, but they also reinforced a very common misconception.
Things get much more interesting – and pretty accurate – when passing through the Jupiter system. The sequence of flying through the Great Red Spot absolutely blew me away.
Of course, you can’t do a Saturn flyby without going through the rings. I’ve heard some complaints that they didn’t get the scale right here, but the thickness of Saturn’s rings vary from as thin as 10 meters to as thick as 1 kilometer.
All things being equal, this was just too cool a shot to pass up, so I’m good with it.
Next was an all-too brief mention of the ice giants Uranus and Neptune. I know it’s an ambitious first episode show and there’s only so much time to devote to such things but I feel bad for those two worlds. To their credit, they took a moment to describe Trans-Neptunian Objects and the icy worlds of the Kuiper Belt, but once again they overcrowded the scene.
It seems that in this new sequence, we are dodging space rocks a-la the Millennium Falcon, which is unfortunate. In reality, there’s even more space between Kuiper Belt objects than there are between asteroids by virtue of the fact that the Kuiper Belt extends so much farther from the Sun than the asteroid belt. Alas, the cool shot wins out and a misconception is reinforced. Bummer.
Interestingly, as Tyson leaves the Solar System, he looks back on the Oort Cloud and notes that the objects there are as far apart from one another as Earth is from Saturn. I guess that’s why he didn’t have to dodge them on the way out. My only observation here, as with any depiction of the Oort Cloud, is that at this imagined distance, the icy comets that populate the cloud are much too small to be seen; The Oort Cloud would be no more noticeable from outside the solar system than it is from our vantage point well within it. And yet there needs to be a way to visually communicate to the viewer that they’re there, so we get a delicate sphere around the Sun.
Jumping forward in the sequence, Tyson continues to define our cosmic address through our diminishing place in the Virgo Supercluster of galaxies. Whenever I see shots like this, I get goosebumps, despite having been familiar with the scale of the observable universe for most of my life. However, I’ll just note that if we really were as far out in between galaxies as depicted in the sequence, we wouldn’t be able to discern each individual galaxy with our own eyes. Remember, each galaxy in an image like the Hubble eXtreme Deep Field is the result of 2 million seconds of exposure time – nothing our eye would ever be able to register in a glimpse, even if we were looking through the Hubble Space Telescope itself. Still…goosebumps!
It’s when we zoom out to the large scale structure of the observable universe that we finally complete our cosmic address.
I’m not sure why they chose to represent this as purple in color, but my guess is that it was inspired by the Millennium Simulation Project, an ambitious model of the gravitational interaction of a whopping 10 billion galaxies. Here is a small piece of their result:
To tell the truth, I wish they had used this image instead of the one they created. Not only is it more realistic, but it makes the observable universe seem larger than it appeared in Cosmos.
When describing the history of the universe, we are (re)introduced to the analogy of an earth calendar. I always thought this was the best way to convey the 13.8 billion-year history of the universe, and the comparatively negligible length of time humans have been around to notice it, to a lay audience. Naturally, this has to start with the Big Bang which, unfortunately, cannot really be properly described even with the most sophisticated of visual effects.
Don’t get me wrong, it was a cool sequence. The problem is that you cannot really depict spacetime expanding into itself, which is what really happened (and is continuing to happen). That’s because there is no outside for the universe to expand into. Perhaps the most accurate way to depict a Big Bang is to show nothing on screen, then show “fire” everywhere. There was a 1991 documentary called The Astronomers that depicted the Big Bang exactly this way. But it’s hard to convey the idea of a massive explosion without showing something…well…exploding. Hmm…
Truth be told, I’d be ok with this had Tyson not made the statement that in the beginning the entire universe was compressed down to the size of an atom. If he had instead said it was the observable universe that was so compressed, it would have made all of the difference. Here’s why:
Most cosmologists generally believe that the universe is infinite. By that definition, it extends farther beyond the farthest points in space we can see. These farthest points define the observable universe, and Tyson makes a point of distinguishing the observable universe from the entire universe, which is infinite.
But here’s the catch – if the entire universe is infinite today, then it must have been infinite in the beginning as well. But how can something be both infinite and compressed down to the size of an atom? It can’t, but the part that defines today’s observable universe can, with all of the points of the infinite universe beyond compressed next to it, and so on. Here’s an illustration from Edward Wright’s excellent cosmology FAQ:
The green circle represents our observable universe, with the galaxies (dots) much closer together a billion years after the Big Bang than they are today. If we run the clock back further to the beginning, our green observable universe would be infinitesimally small, but the dots (representing the galaxies we will never see) will still go on forever.
Alas, by stating that the entire universe was compressed to the size of an atom, I think Tyson may have reinforced a major misconception.
Again, none of this is to take away from what I thought was an amazing production. And truth be told, we need Cosmos on our screens now more than ever. Carl Sagan presented Cosmos at a time of both great exploration of our solar system and of grave danger to our home planet and to humanity’s own existence. Sagan understood that our very survival depends on humankind’s knowledge of the cosmos, and of our place in it.
Today, we find ourselves once again in peril – perhaps not from nuclear annihilation but certainly from a rapidly warming planet – but now amid an ever-increasing wave of science denial. Denial of global warming, modern medicine, biotechnology, and of investments in research. If there was ever a time when we need to present Cosmos to a new generation, it’s now.
You can view the entire episode here. Enjoy the journey.
“The purpose of life is to live it, to taste experience to the utmost, to reach out eagerly and without fear for newer and richer experience.”
Would you take a one-way trip to Mars? Think about that for a moment: would you leave your family, friends, the entire planet Earth behind to live out your days forever enclosed in a sealed habitat on a distant planet, entirely dependent on your fellow colonists and resupply ships from Earth? Here are some people who say they will:
It’s a thought-provoking short film which gives insight into the type of people who are willing to undertake such a journey. All of them applied to Mars One, an ambitious program to select and train the first human colonists to live out their lives on Mars. There are many reasons why this would have to be a one-way mission, but the short version is that by the time humans get to Mars, there would be no way they could survive a return to Earth. Mars’ gravity is less than ½ of Earth’s. Even if we could somehow simulate that environment on the journey to/from Mars, their muscular/skeletal structures would atrophy far too much to make survival in Earth’s 1g environment possible. That’s why the trip would have to be one-way: permanent exile on Mars.
And yet, for these people, such exile would give their lives tremendous purpose, one far different from those of us who would remain behind on Earth. It’s important to consider this because it shows that in a very real sense, humanity is going to have to change in a fundamental way if we ever become a true multi-world species.
When you have one-thousand thirty eight confirmed exoplanets. you get to do some pretty cool things with all of that data. The Open Exoplanet Catalogue put together a really cool bubble chart of these planets’ sizes and temperatures.
Pretty, isn’t it? And there’s a whole lot of information packed into each bubble. The size of the bubble corresponds to the relative size of the planet and its color corresponds to its equilibrium temperature. We can think of a planet’s equilibrium temperature as an idealized case where the planet is only heated by its parent star, and there is no warming or cooling due to the planet’s atmosphere. Of course, that’s never the case in real life and that’s why the the folks at the Open Exoplanet Catalogue were careful to point out that “green might be right.”
Take a look at the visualization yourself and spend a few minutes (or hours) hovering over the planets. Visualizations like these are a great way to explore large sets of data like these all at once. And with another 1,073 (and counting) unconfirmed exoplanets, there’s going to be an ever-expanding dataset to explore.
For any graduate student or postdoc, teaching is a rite of passage. Lucky for me, I got to experience teaching early on as an undergraduate at Villanova University starting in the late eighties as a teaching assistant for the core undergraduate astronomy lab.
That also happened to be the last time I actually taught astronomy lab until now. I’ve done my fair share of public outreach, informal educational activities, school partnerships, and even a weeklong cram astronomy workshop, but formally teaching for realz for a full semester at a university is something I haven’t done in over 20 years, until now.
Last night I taught the first of 12 labs for Astronomy 161 at Towson University. Now, I don’t plan on telling any war stories, but if last night is any indication, there may not be any war stories to tell anyway (I know, famous last words.)
As a subject, astronomy is one of the most counterintuitive to us. It requires to contemplate the greater universe far beyond the trappings of our day to day world. Consider these “simple” questions:
Which direction is East?
Which direction is West?
Where is the highest star in the sky?
Right off the bat, we’re faced with questions that have no bearing on our everyday experience, yet are fundamentally important to understanding our place in the cosmos.
Unsurprisingly, some people were stumped by these questions at first. But it wasn’t long before the light bulbs started going off and one by one, connections to the cosmos were made right in front of me in that lab.
It feels great to be teaching again and I’m kind of kicking myself for not thinking to do this sooner, seeing as I loved it so much going back to my undergrad days. Oh well, I’m here now at Towson and I’m looking forward to the rest of the semester.
To any of my students who might be reading this post, welcome! Feel free to grab a Astr.161 Syllabus in case you didn’t get it from the school’s Blackboard site (which is something else I’m trying to figure out – these new fangled computer internets and all…)
Oh, and feel free to leave your answers to the above questions in the comments below
We had some time to kill today, so Tom Wolf and I made a little video to explain today’s launch postponement. Since making this video, we learned that launch is GO for tomorrow, so yay! My full post is below, but in the meantime…
I woke up this morning in my hotel to a beautiful, albeit cold, morning on Chincoteague Island, VA. I glanced at my email only to discover that today’s launch had been postponed. It wasn’t a problem with the Cygnus spacecraft, nor the Antares rocket, nor (thankfully) a new problem on board the International Space Station. Everything was perfect down here on earth.
But in space, the weather was absolutely horrible. Here’s why:
Holy mother of all sunspots, Batman, those are HUGE! To give you an idea of just how large we’re talking about, let’s make a little comparison for scale:
Those sunspots are the reason for today’s postponement. Sunspots are regions of angelic instability on the “surface” of the Sun. They mark the locations of magnetic field lines that rupture, unleashing a storm of charged particles into space at speeds of up to 2 million miles per hour. Those particles strike Earth’s magnetic field, giving us aurorae at the north and south poles:
Unfortunately, that means a lot more radiation in the near-Earth environment, and this poses a problem for launch. The Cygnus spacecraft is “hardened” against radiation, but the Antares rocket isn’t, and the launch team were concerned that it might play havoc with the rocket’s avionics, hence the postponement.
Yesterday, Orbital Sciences rolled out the Antares rocket to the launch pad, hoping for a launch of Orb-1 to the International Space Station tomorrow. I’ll be heading down to Wallops Island tonight and will be out in the cold watching the launch (yes I know, I’m really taking one for the team here.)
As the trajectory for tomorrow’s launch hasn’t changed, I updated my launch viewing guidewith the planned launch window.
Launch is scheduled for tomorrow, January 8 at 1:32pm EST. Hope you get to see it from where you are!
On Christmas Eve, 1968, the crew of Apollo 8 were in orbit around the Moon and became the first human beings ever to witness the Earth rising over another world. Using data from the Lunar Reconnaissance Orbiter, we now have a incredible recreation of what they saw from inside their Apollo spacecraft. Be sure to go to high definition and full screen:
Quoting their description on YouTube:
In December of 1968, the crew of Apollo 8 became the first people to leave our home planet and travel to another body in space. But as crew members Frank Borman, James Lovell, and William Anders all later recalled, the most important thing they discovered was Earth.
Using photo mosaics and elevation data from Lunar Reconnaissance Orbiter (LRO), this video commemorates the 45th anniversary of Apollo 8′s historic flight by recreating the moment when the crew first saw and photographed the Earth rising from behind the Moon. Narrator Andrew Chaikin, author of A Man on the Moon, sets the scene for a three-minute visualization of the view from both inside and outside the spacecraft accompanied by the onboard audio of the astronauts.
The visualization draws on numerous historical sources, including the actual cloud pattern on Earth from the ESSA-7 satellite and dozens of photographs taken by Apollo 8, and it reveals new, historically significant information about the Earthrise photographs. It has not been widely known, for example, that the spacecraft was rolling when the photos were taken, and that it was this roll that brought the Earth into view. The visualization establishes the precise timing of the roll and, for the first time ever, identifies which window each photograph was taken from.
The key to the new work is a set of vertical stereo photographs taken by a camera mounted in the Command Module’s rendezvous window and pointing straight down onto the lunar surface. It automatically photographed the surface every 20 seconds. By registering each photograph to a model of the terrain based on LRO data, the orientation of the spacecraft can be precisely determined
Another day, another rocket launch out of the Mid-Atlantic Regional Spaceport. This time it’s an Antares rocket carrying a Cygnus cargo ship up to the International Space Station. Orbital Sciences corp launched a Cygnus to ISS back in September as a demonstration flight, giving NASA and Orbital the experience to take on regular resupply flights to the station, beginning with this week’s launch.
Antares was rolled out to the launch pad last night and there’s a really nice photo set on Flickr you can check out. Launch is currently scheduled for 9:19 pm Eastern time on Thursday, Dec 19, and yours truly will be there to cover it because they gave me press credentials (does happy dance).
Now keep in mind that NASA are currently working a cooling pump problem aboard the space station. They’re not sure if they can limp along with a backup system or if they will need to do a spacewalk to make repairs. If they decide to go ahead with an EVA, this launch could be postponed again, so stay tuned.
Be sure to check out their page as they have several visualizations from New York, Philly, Baltimore, Washington DC, and Norfolk VA, among other places. They also have a Google Earth KMZ file which you can download and use to get an idea of what the launch trajectory will look like from your location. Here’s a few I created:
What you should expect to see, and when
Antares is a liquid-fuel rocket, which means it should produce a yellow-white colored exhaust arcing quickly across the southeastern sky like what you see in the images above (except at night).
The launch window is from 9:19 – 9:24 pm EST on Thursday (02:19 – 02:24 am GMT Dec. 20) . 1:32-1:37 pm EST on Wednesday (18:32-18:37 GMT).They’ll try to launch on time at 9:19 1:32 but keep in mind that the farther you are from the launch site, the longer it will take for the rocket to clear the horizon. The images I show above assume a flat horizon all the way to Wallops, and we know that’s not the case. Fortunately, Orbital created a first sighting map to give you some idea of when you should expect to see the rocket clear the horizon (keep in mind though that it would have already moved slightly eastward by the time you pick it up).
Antares is a two-stage rocket, so it will appear to dim and then light up again a little further to the east as the expended stage is jettisoned and the next stage ignites.
Monitor the launch on your smart phone, but watch the timing
You can also monitor NASA Wallops on Twitter and Facebook as well to stay on top of the countdown and make sure nothing has been postponed so you can time your viewing just right.
…keep in mind that everything coming down to your tablet or cell phone is probably going to be a minute or so after the fact. If you wait until you hear them say “liftoff” to go outside and look, the rocket may already have reached orbit. Instead, listen to / follow the countdown to make sure the launch time hasn’t changed, and then use your cell phone’s clock to make sure you’re really at L-0, *then* look toward Wallops!
Watch with friends to increase your chances of actually seeing it
Even at night, the rocket may be hard to spot, especially if this is your first time. Haze, aircraft, and all kinds of things can be in the field of view to confuse you even more. If you’re with a small group of people, chances are that one of you will be able to spot it and point it out for the rest. Watch with friends to increase your chances!
Watching and tracking rocket launches is challenging and fun, especially at night. Hopefully the weather from your location will cooperate and you get to see an amazing show. Good luck!
Some cool bits to note: At 2:50, the spacecraft begins to rotate itself so that it’s underside points downward toward the lunar surface. At 5:00, the descent stops and hovers above the surface. At 5:30, you can see the spacecraft has adjusted itself to avoid an obstacle and then continues its descent. A little while later, we’re picking up some dust and we’ve landed!
What’s really amazing is that all of this was accomplished autonomously, with no assistance from the ground. How cool is that?