Weather

It’s Sol 4 on Mars for Phoenix. And although I haven’t been able to find a link to a consistent weather report, there is this:

From the Website:

The weather, as taken by the Canadian meteorological station, at the Phoenix landing site on Sol 4 was sunny with increasing dust, and therefore decreased visibility. Temperatures ranged from a high of minus 30 degrees Celsius (minus 22 degrees Fahrenheit) and a low of minus 80 (minus 112 degrees Fahrenheit). No wind measurements were available for Sol 4.

Even better

Even better than the last post, this one. It puts the Phoenix and parachute image in a bit of context. In this case, Heimdall Crater

To understand what’s going on, look at the box at the bottom left. It’s the magnified portion from the middle left part of the crater. On the larger photo, all you see is a speck of white, but that’s Phoenix

Click on the image to see it in full resolution.

It looks like Phoenix is headed for Heimdall, but really, it’s 20 km in front (towards the camera) of it. For a sense of scale, Hiemdall itself is ten km across, and the lander is 12 km above the surface. It just looks like it’s falling into the crater.

A little thing called parallax.

Soft landings

This is an amazing photograph.  Take a moment and look – really look – at it, and try to figure out what you’re seeing.

This is in fact the Phoenix Mars Lander, with parachute fully deployed.  The photo was taken by the HiRISE camera on NASA’s Mars Reconnaissance Orbiter. The brightness has been adjusted to make the parachute more obvious (it was bright daylight a landing).  If you look very closely, you can even see the shroud lines connecting the parachute.

The Orbiter is about 310 km above Mars’ surface, and Phoenix is about 12 km in altitude.

Phoenix has landed

The big news of the weekend is that the Mars Phoenix Lander has, in fact, landed. It touched down in the northern hemisphere at about 6pm (Calgary time) on Sunday. All seems well, and all systems are, as they say, a go.

Here’s one of the first images to be sent back from Vastitas Borealis (the Northern Wastelands).

Two special points need to be made about the Phoenix. The first is that this is the first controlled descent landing in a long time (since Viking, in 1976, in fact). All of the recent landings have involved air bag softened collisions with the surface. The second is that this is the northern most landing on Mars, at 68 degrees north latitude.

There are four broad goals to the Phoenix program (including the ever popular “prepare for human landing”), but the main mission is to find water. Previous orbiters have discovered indirect evidence of water, but Phoenix will dig for the frozen stuff with a specially designed “frozen stuff digger tool“.

And of course, the Canadian Space Agency has supplied the Meteorological package (a fancy word for “weather station”).

The latest news can be found here (from the official NASA site).

The latest imagery can be found here.

Seeing Spots

Everyone knows about Jupiter’s Great Red Spot, a centuries old storm that can fit about ten Earths in it. But there are two other “red spots” over there as well. The latest discovery, about half the size of Earth, is in the same neighbourhood.

Courtesy of NewScientistSpace.com:

Now, a third red spot, about half the size of Red Spot Junior, has broken out on the giant gaseous planet. The spot, previously a white storm, now appears red in Hubble Space Telescope images taken on 9 and 10 May. The observations were led by Imke de Pater of the University of California, Berkeley, US.

No one knows for sure what gives the three spots their red colour. But one theory is that especially violent storms dredge up material from deeper in Jupiter’s atmosphere, such as phosphorus-containing molecules, which undergo chemical reactions that turn them red when exposed to sunlight.

Mars Phoenix Lander

The Mars Phoenix Lander will be the next Martian probe to be land on the Red Planet.  Real soon now.  As in, on Sunday.

From the Phoenix Mars Mission homepage:

Mars is a cold desert planet with no liquid water on its surface. But in the Martian arctic, water ice lurks just below ground level. Discoveries made by the Mars Odyssey Orbiter in 2002 show large amounts of subsurface water ice in the northern arctic plain. The Phoenix lander targets this circumpolar region using a robotic arm to dig through the protective top soil layer to the water ice below and ultimately, to bring both soil and water ice to the lander platform for sophisticated scientific analysis.

The complement of the Phoenix spacecraft and its scientific instruments are ideally suited to uncover clues to the geologic history and biological potential of the Martian arctic. Phoenix will be the first mission to return data from either polar region providing an important contribution to the overall Mars science strategy “Follow the Water” and will be instrumental in achieving the four science goals of NASA’s long-term Mars Exploration Program.

One of the exciting things about this mission is the Canadian involvement.  The Canadian Space Agency has contributed an important package – a weather station.

Canada’s contribution to Phoenix is a meteorological station that will record the daily weather of the Martian northern plains using temperature, wind and pressure sensors, as well as a light detection and ranging (lidar) instrument. The weather station will help improve models of the Martian climate and predict future weather processes, paving the way for future exploration missions. This information may also improve scientists’ understanding of Earth’s dynamic polar regions by comparison between the two planets. Resembling a brilliant green laser, the lidar will probe what is known as the “boundary layer” of the Martian atmosphere (the turbulent layer of the atmosphere about 7-10 km above the surface) and provide information about the structure, composition and optical properties of clouds, fog and dust in the lower atmosphere (up to 20km above the landing site).

Astronomy (to end of the year)

Here is a list of projects that I have assigned, and which I will expect to be completed before then end of June 17, the last day of CTS classes (NOT core classes, just options). If you seek that coveted “A”, then all assignments must be completed and completed well. I will accept any of these assignments (many are submittable via email) up to and including June 17.

The bottle rockets will be expected a little earlier, as we will be launching on June 10 and 12, weather permitting.

But do be aware that just because assignments have been handed in by the deadline, it doesn’t mean that they have been done well or completely. Some of these assignments require an email conversation between you and I to flesh out your responses, and to help you answer fully and completely. If the first time I hear from you about assignment 5 (Big Questions) is on the 17th, then I guarantee you will not do well on that item.

All assignments can be found on the PDQ Science page.

Here’s what I will be evaluating:

Assignment 1 – astronomy picture of the day (a WP doc attached to an email)
Assignment 2 – wikispaces registration and login (for completion)
Assignment 3 – your wiki page, with links, photos, references (if you do more than one, you need to inform me via email with the links).
Assignment 4 – What is a rocket. (a WP doc attached to an email)
Assignment 5 – big questions in astronomy (this is an email conversation answering two or three of the big questions listed)
Assignment 6 – building the bottle rocket (necessarily done in class)
Assignment 7 – calculating rocket altitude (this will be assigned presently)

Astronomy Treasure Hunt

An astronomy treasure hunt.  Email to mister.buracas@gmail.com.

1. What is the last name of the person who discovered Pluto?
2. How many planets have rings?
3. About how many stars are visible with the naked eye?
4. What is our closest extra-galactic neighbour?
5. What was the first human made object to leave our solar system?
6. What did Percival Lowell discover on Mars
7. Where did did men last walk on the Moon?
8. Where were rockets first invented?
9. What was thefirst living thing sent into space?
10. What is at the center of the Milky Way

First come, first served with a prize, no less.

The galactic plane

Our galaxy, the Via Lactae, is round and flat. Like a frisbee, only with a bulge in the core. It’s called, oddly enough, the galactic core, and there’s very likely a black hole in that core. (But that’s another story.)

So yeh, we live on the rim of a flattened galaxy. When we view the Milky way from Earth, we’re looking through the edge of it, sort of like when we look at the edge of the rings of Saturn. Here’s a photograph from Japan’s Akari satellite taken in the infrared wavelength (ummm, infrared? huh?).

Remember, we’re taking this picture from within the Milky Way… we’re in the outer reaches!

Notice that the galactic disc is thin. Ish. The Milky Way is about 1 000 light years thick, but over 100 000 light years in diameter.

Now, to the point of this posting. Our solar system is on the edge of the galaxy. But guess what? we’re not standing still. No, we’re slowly rotating around the galactic core (like a satellite around a planet, or a planet around a star). We make one orbit in about 150 million years or so, and this is known as the galactic year.

But our “orbit” also wobbles a bit, up and down with respect to the galactic plane. You can imagine that when we cross through the middle of it, where it’s thicker, that there’s a lot of dust a debris and stuff.

Well, there is. And every 35 to 40 million years we cross the dusty area, and our chances of colliding with a comet increase by ten times. It’s what scientists think wiped out the dinosaurs 65 million years ago. Here’s the article from Cardiff University (it’s in Wales, in the UK):

Scientists at the Cardiff Centre for Astrobiology built a computer model of our solar system’s movement and found that it “bounces” up and down through the plane of the galaxy. As we pass through the densest part of the plane, gravitational forces from the surrounding giant gas and dust clouds dislodge comets from their paths. The comets plunge into the solar system, some of them colliding with the earth.

The Cardiff team found that we pass through the galactic plane every 35 to 40 million years, increasing the chances of a comet collision tenfold. Evidence from craters on Earth also suggests we suffer more collisions approximately 36 million years. Professor William Napier, of the Cardiff Centre for Astrobiology, said: “It’s a beautiful match between what we see on the ground and what is expected from the galactic record.”

Big questions in astronomy

The field of astronomy is full of big questions. How old is the universe? What came before the big bang? How do we know that there’s a watery planet around a star that’s 20 light years away?

Well, astronomy’s full of questions like that. We’ll begin by looking at – and answering – some basic questions in astronomy.

1. Where are we?
2. How old is the universe? How do we know?
3. How can we calculate the distances to stars?
4. How can we tell what stars are made of?
5. How do we know that galaxies are moving away from each other?
6. What are black holes, and why do they exist at the center of every galaxy?
7. How do we know that men walked on the moon and that it was not a hoax?
8. How do we know the Earth is a sphere, and not flat?
9. How do we know that the Heliocentric model is the correct one to describe our solar system?

Your job is to find the answers to these questions, and to explain them to me.

You will do this by email. You will research the answers, and then (in your own words, please) explain to me why and how. It might seem like an easy assignment, but I assure you that I will have questions of my own, which I will pose back at you through email.

This will probably take a few email exchanges between you and I, so be sure to check you email. When you have answered the question to my satisfaction, you will get one last reply from me with the keywords “YOU GOT IT!) in the subject line.

Until you get that last email from me, then your job is not done.

My email addy is, as usual, mister.buracas @ gmail.com. Please include your last name in the subject line, or it might not get an answer.

Carry on!