Watching the space station in twilight last week – Bob King/News Tribune

The Space Shuttle Discovery will take off this afternoon from Florida to dock with the International Space Station (ISS) on a two week long mission to install components of the Japanese Kibo scientific laboratory and its robotic arm system. This will be the 123rd shuttle flight — the first was launched in 1981.

We’ll have a Minnesotan on board Discovery’s seven-person crew. She’s 38-year-old mission specialist Karen Nyberg (at right), who hails from the small town of Vining, Minn. Her job will be to operate all three of the robotic arms on the station during her stay. Nyberg wanted to be an astronaut from the time she was in elementary school.

In her words: "Well, I decided when I was a little kid that I wanted to be an astronaut and, honestly, I can’t pinpoint an event or a person or anything that made me decide that. I just decided that that’s what I wanted to do and I kind of kept that with me." You can read more about Karen, including her passion for quilt making and painting, in this NASA interview.

The space station (ISS) continues to pass over our region during evening hours through June 7. As the Shuttle nears the ISS, I’ll update the blog with times when you can see both craft chasing each other like cat and mouse in the sky. For now, here are a couple times to watch for the station: ** UPDATE: Times now listed for the shuttle below.

* Tonight starting at 10:15 p.m. The space station will rise in the W-NW and follow an arc to the east, passing four outstretched fists above the horizon. It will do it again at 11:50 p.m. The space shuttle will follow the same path seven minutes later, appearing at 10:22 p.m. and 11:57 p.m.

* Tomorrow night June 1 starting at 10:37 p.m. (same time for the space shuttle, too.) The station will rise in the W-NW and arc over to the E-SE, passing nearly overhead. This will be an exceptionally bright pass!

The American flag and a mini-DVD on the deck of the Phoenix lander. The mini-DVD
from the Planetary Society contains a message to future Martian explorers, science
fiction and art inspired by Mars, and the names of a quarter million people.
NASA/JPL/Caltech/University of Arizona

Phoenix has now returned a couple very detailed panoramic photos of the Martian landscape around the lander. The images are large and and will require a couple minutes to display but oh, are they worth the wait. You’ll almost feel like an astronaut or geologist as you use your mouse to explore scene one and scene two. Notice the low range of hills in the second image. They’re likely the upraised rim of a crater. 

We have rain today and rain tomorrow. I’m happy for rain and the two atoms that compose the water in all those drops. Hydrogen and oxygen. Think for a minute about the origin of those elements. Hydrogen makes up about 75% of all the known matter in the universe, and was created some 13.7 billion years ago in the Big Bang. Hydrogen, with just one proton and one electron, came out the hot mix with ease.

Oxygen is more complicated. It has eight protons and eight electrons. It had to be cooked up later in the cores of stars, where hydrogen and helium fuse together under the star’s tremendous heat and pressure to create heavier elements like carbon, oxygen, neon and many more.

During the formation of the solar system from a cloud of gas and dust 4.7 billion years ago, hydrogen and oxygen happily combined to form water molecules. Almost five billion years later, you and I rush to our cars to avoid getting soaked by the rain.

Next time you’re hurrying in the rain, consider the epic journey all those hydrogen and oxygen atoms have been on since the dawn of time. And slow down a little.

Astro Bob’s vision of the Big Bang — dang hot!

Spring is seductive. The sky cleared late last night and I found myself wondering whether to go to bed or just stay out. It must have been the sound of the wind in the leaves that caught hold of me. Or maybe it was the pull of the Milky Way in the east. I offered no resistance and finally turned in just before two. 

I thought it wise to check on our friend Nu Draconis (see yesterday’s blog).  That’s when I noticed that the later it got, the more the star turned over to the left side of the trapezoid instead of being at the very top. If you do seek this double star, and are having difficulty in deciding which one it is, just pick the faintest of the four stars. My 10x binoculars easily split Nu-1 and Nu-2 into side-by-side white pearls.

The Big Dipper is high overhead in the northwestern sky around 10-10:30 p.m.
on May evenings.  

Last weekend I came across three earthly Ursa Majors (bears) in the woods, and despite my efforts to leave them in peace, we kept crossing each other’s trails. Finally, I walked out onto a nearby dirt road thinking they wouldn’t follow. But not two minutes later, here comes the mother and two cubs headed in my direction once more. I watched them from afar with binoculars until they lost interest and walked down to the creek. Later that night, that famous, starry bear circled overhead, so I finally took the hint and decided to write about bears — the celestial variety, naturally.

The Big Dipper is part of a much larger constellation called Ursa Major, the Great Bear. To find it, just look way high up in the northwestern sky near the end of twilight. All the Big Dipper’s stars have Arabic-derived names. Here’s a list of them and their meanings:

Alkaid (AL-kade) = the leader
Mizar (MY-zar) = waistcloth or apron
Alcor (AL-core) = the bull
Alioth (AL-ee-oth) = tail of a fat sheep
Megrez (meg-REZZ) = root of the tail
Phecda (FEK-da) = the thigh
Merak (MER-ak) = loin of the bear
Dubhe (DOOB-huh) = back of the bear

Rarely do the stars in constellations have anything to do with each other. They’re all at different distances, and appear to form shapes like hunters, scorpions and the like by chance alignment. This isn’t the case with the Big Dipper. It’s one of those rare constellations where the stars are part of a actual cluster like the Pleiades (Seven Sisters) or the Beehive. Called the Ursa Major Moving Cluster, it’s about 75 light years away, and includes all the Dipper stars except the two end members, Dubhe and Alkaid.

Like my bears in the woods, the stars of the Big Dipper keep together, and if you’re lucky enough to have clear skies, they’ll follow you all night.

(Ursa Major with Big Dipper at right — Stellarium)

Photographs of the Phoenix lander, parachute and heat shield taken by the Mars
Reconnaisance Orbiter this week. You can even see the ear-like solar arrays on the lander.  – NASA/JPL/CalTech/U of Ariz.

Looks like another sunny day with a breezy 12 mph wind from the northeast. The high temperature will be around -20 below with a predicated low around -112 below. What? Another spring day in Duluth? Sorry to disappoint local weather fanatics but this is a typical day at the Phoenix lander site in the Martian arctic. For comparison, the average temperature the past few days at the Amundsen-Scott south pole weather station in Antarctica has been hovering around 80 below with light northeast winds and blowing snow. Neither place sounds very hospitable but at least there’s air to breath at the south pole. Mars’ atmosphere is nearly all carbon dioxide and much too thin to breath anyway.

Facing east around 10:30 p.m. this week. Look for bright Vega, and
above it, the skewed square that marks the head of the dragon — Stellarium

Let’s go on a double star hunt this week. The star of the hour is Kuma or Nu Draconis, the faintest star in the head of Draco the dragon, who we visited in a blog earlier this week. You might remember that Draco is a large constellation winding between the Big and Little Dippers. The head of the dragon is a trapezoid of four stars located one outstretched fist above brilliant Vega. Vega is that unmistakably bright, white star visible in the northeastern sky during twilight.

To your eye, Nu Draconis looks like a single star but 10x binoculars will resolve it into a tiny pair of "headlights". Be sure your binoculars are focused sharply. You might be able to split the two with 7x if you brace yourself against a wall or car, or place the binoculars on a tripod.

The two stars, called Nu-1 and Nu-2, revolve around one another in space with a period of 44,000 years, and are separated by 177 billion miles. That’s about 47 times the distance between Pluto and the sun. Man, there’s lots of space out there.

Pick up your binoculars the next clear night, and try your eye at some star splitting. Wouldn’t you love to be able to say: " I Nu I could do it."

Sorry, that was a bad one but I couldn’t resist

Iridescence in lenticular clouds last week over downtown Duluth – Bob King/News Tribune

Mars and other stellar matters have kept things hopping this past week, but I wanted to share a photo with you of a colorful sky phenomenon called iridescence. I saw these clouds passing near the sun last week here at the News Tribune, and ran out to take a picture before they dissipated. By blocking the sun with a street light, it was easy to see several arcs of vivid color.

The arcs are caused by interference. Recall that light can be described as a series of waves. When the waves of light are diffracted or bent by the tiny droplets along the edge of the cloud, they can either reinforce each other or cancel each other out. This happens to each color of white light – the whole rainbow spectrum – creating a series of colorful rings or arcs along the cloud edge. The same phenomenon was responsible for the aureole around the moon more than a week ago.

 The purity of color and multiple arcs only form when the microscopic cloud droplets all have nearly identical sizes. While scanning the sky for this wondeful color show, you’ll usually find it near the sun. Sunglasses can make spotting it not only easier but more comfortable. For a more complete description of iridescence, please check out this link.

Phoenix lander takes a look around – NASA/JPL/CalTech/U of A

Here’s one of the latest photos taken by the Phoenix lander on Mars. It shows part of the lander, a section of solar panel (at left) and lots of pebbles. Below is a very realistic artist conception of the lander on the planet with its two large solar panels and robotic arm.

Artist conception of Phoenix lander on Mars – NASA/JPL/CalTech/U of A

MRO photo of Phoenix descent to the surface yesterday — NASA/JPL-Caltech/U of A

Talk about an amazing photo. Take a look at this image, the first-ever picture made of a spacecraft landing on another planet. It was taken by the Mars Reconaissance Orbiter, and shows the Phoenix lander suspended from a parachute during its descent to Mars’ surface. Wow!

Phoenix landed right on target in an arctic plain riddled with polygonal cracking. This peculiar landscape is caused by the seasonal expansion and contraction of water ice below the surface. It’s common in permafrost areas on Earth, and has also been photographed from orbit on Mars. Sometime in the next week, Phoenix will use its robotic arm to dig into the soil to test for the presence of ice.

Polygonal cracking on the North Slope of Alaska – photo by Matthew Druckenmiller

Polygons at the Phoenix lander
site – NASA/JPL-Caltech/U of A

If you’re excited the mission, and would like to see Mars for yourself, just look to the western sky during twilight this week. Use the map below to locate the red planet, and in your mind’s eye, imagine a strange world of polygons, huge extinct volcanoes, monster-sized craters, ancient river beds, dust storms and ice.

Mars and friends around 10-10:30 p.m. this coming week – created with Stellarium

A first look at the Martian surface and one of the Phoenix landing pads - NASA/JPL

The Martian arctic landscape taken shortly after
landing by the Phoenix stereo camera. Notice that
the soil is broken into plates. This pattern is called polygonal
cracking, and is also seen in permafrost on Earth. It’s
caused by seasonal freezing and thawing of ice. - NASA/JPL

We did it – we arrived again safely on the red planet. It was a splendid touchdown, and Phoenix is sending more images as you read this. If you’d like to see them all, click here. To watch a video of mission control’s reaction to the landing, and for a more complete story, click on this link.

News report from NASA:
Pasadena — A NASA spacecraft landed in the Martian arctic today to begin three months of examining a site chosen for the likelihood of having frozen water within reach of the lander’s robotic arm.

Radio signals received at 4:53 p.m. Pacific Time confirmed that the Phoenix Mars Lander had survived its difficult final descent and touchdown 15 minutes earlier. In the intervening time, those signals crossed the distance from Mars to Earth at the speed of light.

Mission team members at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.: Lockheed Martin Space Systems, Denver; and the University of Arizona, Tucson, cheered confirmation of the landing and eagerly awaited further information from Phoenix later tonight.

Artist conception of Phoenix just before touchdown this evening / NASA

This is the big day. If all goes according to plan, the Mars Phoenix lander will land safely in the Martian arctic just before 7 p.m. Central time. It’s equipped with a stereo camera to take pictures of the landscape, a robotic arm for digging beneath the surface, and two microscopes for close-up examination of the Martian soil. Inside the lander, there is a mini-chemistry lab where soil samples will be tested for their contents, including anything organic. The microscopes will study the soil particles on site, looking for signs that they’ve been shaped by water. If scientists find clay on Mars, that would almost certainly indicate liquid water was once present on the planet.

We take clay for granted around here. It gets stuck in our shoes and carried into the house. And if it wasn’t for all that $%^&@! clay, gardening would be a whole lot easier in our region. But ultimately, clay is rock that’s been weathered by water. And scientists believe that if you follow the water trail, you might turn up the possibility of life.

Animated orbital view showing Mars’ north polar cap and dust storm passing over
the Phoenix landing site (tiny oval at the 10 o’clock position) from May 16-22 / NASA

The forecast is for clear skies today at the landing site. There was a minor dust storm, which you can see passing over the oval landing site, but that has moved on. As long as Phoenix doesn’t hit a boulder before touchdown, we should be OK. Stay up to date with the latest news by visiting NASA’s Phoenix Mars Lander site.

Moon at closest (left) and farthest from the Earth – photo by Jim Schaff

I also want to share a wonderful image made by Jim Schaff, a member of our local Arrowhead Astronomical Society. It shows the moon at perigee and apogee – the closest and furthest points from Earth during its monthly orbit. The moon’s elliptical or oval orbit causes its distance to vary from our planet during each monthly cycle. Making the images took careful planning on Schaff’s part.

"I completed a project I was working on this past week. I was able to get the apogee moon this past Tuesday morning around 1 a.m. I was battling the clouds for the picture. It is not quite as sharp as I would have liked, but at least I got it," said Schaff.

Jim then copied and pasted the two images into one picture using Photoshop Elements. The difference in size is amazing, isn’t it? 

Thanks Jim, for this excellent illustration.

Look high in the north to find Draco around 10:30 p.m. – created with Stellarium

As we walked toward the east, my older daughter remarked last night how many stars she could see in that direction. The spare spring sky is giving way to the richness of summer and the Milky Way. Vega is the vanguard star for a whole troop of warm weather constellations.

Would you like to try your eye at one of them? There’s a huge swath of starry sky between the Big Dipper and Vega that’s home to one of the largest constellations, Draco the Dragon. I wish I could say this was an easy pattern to spot, but the dragon has no particularly bright stars. Still, its twisty, serpentine shape stands out nicely, once you’ve connected the dots.

Start with the two stars at the end of the Dipper’s Bowl. The first star you’ll see below them is the tip of Draco’s tail. Now work your way eastward, in stepping stone fashion, around the coils and curves of the tail toward brilliant Vega. The head of the dragon is a compact, keystone-shaped group about one outstretched fist to the left of Vega. It’s also the brightest and easiest part of the constellation.

Draco is a favorite at the UMD planetarium shows, because it’s one of the few constellations that looks like what it’s supposed to be. Dragons are scary, too, and children love that.

You guys have been busy with the space station so let’s keep the passes coming. Here’s a table for the next few days. Last night’s pass was really bright, and we even saw a short flare. Flares are caused by strong, brief reflections from one or more of the surfaces of the ISS. For measuring the ISS’ maximum altitude, one fist is equal to your balled up fist held vertically at arm’s length against the sky. The higher the altitude, the brighter the pass.

The space station zips across the telescope field of view last night – Bob King

We had two International Space Station (ISS) passes last night, and I hope you got to see them. Both were brilliant. I managed to chase down the station in my telescope at low power on each occasion. To do it, I pointed the telescope’s finderscope, a 10x telescope with crosshairs like a riflescope, in the direction of the ISS. After watching its motion for a few seconds, I then set the ISS off to one side of the field of view, so its path would take it over the crosshairs. I rushed back to the eyepiece and caught my target — which at 64x was moving VERY quickly — as it crossed the field. A steady push on the telescope kept the ISS in view. It felt like I was chasing a fleeing mouse.

On each pass, it was a thrill to discern the outline of the craft, especially those big, orange solar arrays the station uses to create power. The drawing above is a little crude but gives you a pretty good idea of shape and color. The panels are obvious, but seeing detail on the station requires a steady, smooth hand and great patience. Last night the station modules blended into one brilliant, white blob.

Enterprising telescope owners may want to try their own hand at seeing the station up close. At an altitude of 200+ miles, you wouldn’t think it possible, until you realize that the ISS is about as big as a football field. I don’t know what the lowest magnification would be to see the station’s "H" shape, but I’d guess 30x would do it.

Mars was in stellar company last night as well, wreathed by the stars in the Beehive Cluster. It’ll be there tonight and tomorrow night, too. The contrast between the pink planet and pearly white stars was awesome. The view (at right) shows what the scene looked like in binoculars or a small telescope.

The moon rises after midnight in Sagittarius tonight, a fine opportunity to get a sneak peak at the summer Milky Way in a dark sky. That means staying up later, too, but what the heck, it’s a Friday!

I’d suggest a drive to the country between 11:30 and midnight. Find a place with a wide open vista to the east, let you eyes adjust to the darkness, and take in the sweep of that glorious, cloudy band of starlight. If you notice three stars in a big triangle smack in the middle of it all, you’re seeing summer’s most famous asterism. It’s called the Summer Triangle, and the stars Vega, Deneb and Altair mark the three apexes.

The Milky Way is our home galaxy, and the sun one of the 200 billion stars that inhabit it. We circle around the galaxy’s center — in the direction of the constellation Sagittarius –once every 226 million years. We are a spark in the stardust on a great journey.

Enjoy the raw beauty of it all. Let it make you feel small. Good observing!

A wide sweep of the eastern sky at midnight with the Milky Way – created with Stellarium