Tag Archives: astronomy

Far Out, Dude! (Really, We Mean It…)

This artist's concept shows NASA's Voyager spacecraft against a field of stars in the darkness of space. (NASA/JPL-Caltech).
This artist’s concept shows NASA’s Voyager spacecraft against a field of stars in the darkness of space. (NASA/JPL-Caltech).
When I was 11 years old, my family went on a 1,500 mile, two-week, car trip from New England to Florida. I got to see New York City and Washington, D.C., from the car window. Highlights of the trip included Disney World and the Kennedy Space Center at Cape Canaveral. However, I was trapped in a station wagon with my older brother and sister for two weeks. To me, it was a very long voyage.

What did I know?

In 1977, three months after I returned to Connecticut, NASA launched two spaceships from Cape Canaveral. They were named Voyager 1 and Voyager 2. Their mission was to go as far from the sun as possible, to take the longest voyage ever.

The thing is: space is really big. It takes a really long time to get around.

The two Voyagers spent more than three years flying through the middle of our solar system, giving us Earthlings our very first up-close views of Jupiter and Saturn. The images they sent back were incredible — rings were found around Jupiter, volcanoes were seen on Jupiter’s moon, Io…

However, the Voyagers only gave these worlds a passing look, like driving past New York City going 100 miles per hour. It would be up to future missions to return to the outer planets for more in-depth research.

The Voyagers didn’t even slow down as they flew by the planets. While Voyager 2 took the long road, spending another ten years checking out Uranus and Neptune, Voyager 1 left Saturn in 1980 and headed out of town.

At this point, it is important to remind you that space is really big. It takes a long time to get anywhere! And the solar system is much bigger that orbit of Pluto (See: What Happened to Pluto?).

In August 2013, scientists determined that Voyager 1 had left the solar system. It is the first machine built by humans ever to leave the solar system — truly a triumph for all mankind! It is about 11.8 billion miles away in interstellar space, the space between stars! Voyager 2 is about four years behind. Their journey will continue for another 40,000 years before they reach another star.

The Golden Record sent with the Voyager Spacecraft. (NASA)
The Golden Record sent with the Voyager Spacecraft. (NASA)
In case space aliens ever find the Voyagers, NASA put some amazing items inside to explain Earth and humanity to them. There is a golden phonograph record album (before there were CDs or compact discs, there were phonograph records … ask your parents). Recorded on the album are samples of 55 Earth languages, and various music selections, everything from Mozart to rock-n-roll legend Chuck Berry. Steve Martin, (the comedian, author, actor, & musician) noted that it is quite possible, thanks to Voyager, that the first message we ever receive from an alien space civilization may very well be them asking us to “send more Chuck Berry”. Far out, in every sense.

Fun Phineas Facts

We are still in contact with both Voyagers. They have a radioactive power source onboard with lots of power and still send data regularly. Due to the vast distances, it takes over 35 hours to get a response after sending a message to them. By timing how long these communications take, we can calculate exactly how far away they are at all times. The messages travel at 186,000 miles per second – the speed of light.

Can you make the calculation yourself to solve how far away Voyager 1 is? Grab a calculator and be sure to ask you math teacher for help if you need it!

— Time to send message and get reply back from spacecraft: 35 hours
— How fast the messages travel: 186,000 miles per second
— Question: How far away is the spacecraft, in miles?

Process:
1. Determine the number of seconds in an hour (60 minutes times 60 seconds)
2. Multiply the number of seconds per hour times 35 hours (the total time it takes to send and get a reply)
3. Multiply your total by the speed of light — 186,000 miles per second. This gives you the total number of miles the message traveled.
4. Divide your answer by 2, since the message made two trips — one to the spacecraft and one back home.


References:

NASA Voyager Site

Voyager Program

More Info on Voyager’s Golden Record

Spotting the International Space Station

Astronaut Chris Cassidy works outside the space station on May 11, 2013.  Credit: NASA
Astronaut Chris Cassidy works outside the space station on May 11, 2013. Credit: NASA
Almost everyone has heard of the International Space Station (ISS). It is one of the most spectacular technological achievements ever, but it is easy to take it for granted. After all, it has been in orbit for more than 13 years. Astronauts have lived on board all that time, conducting science experiments and learning the kinds of things that will help humans extend their reach into space. Since ISS may be the coolest laboratory ever built, we recommend making a New Year’s commitment to keeping track of what’s going on there.

Luckily, NASA makes it easy to keep up with ISS. On the web site http://spacestationlive.nasa.gov/ you will find animations and education resources about “humankind’s permanent outpost in space.” You can find details of the daily activities for each astronaut, along with timelines and live video feeds. You can view the same data being viewed by ground control officers at NASA, so if you’ve ever wanted to try your hand at being a flight director, start here.

For an overview of what is going on with ISS, NASA provides a great option. The YouTube channel ReelNASA provides a weekly newscast about what’s happening aboard the International Space Station. You’ll find links to in-depth information about the experiments and projects that are discussed. You can even send in your own questions. It is pretty cool.

The space station, including its large solar arrays, spans the area of a U.S. football field, including the end zones, and weighs 924,739 pounds. The complex now has more livable room than a conventional six-bedroom house, and has two bathrooms, a gymnasium and a 360-degree bay window.
The space station, including its large solar arrays, spans the area of a U.S. football field, including the end zones, and weighs 924,739 pounds. The complex now has more livable room than a conventional six-bedroom house, and has two bathrooms, a gymnasium and a 360-degree bay window.
Spotting the International Space Station
For the ultimate in “keeping up with the ISS,” nothing beats taking a look with your own eyes. The ISS is the size of a football field and orbits Earth at an average altitude of 220 miles. Just before sunrise or when night has fallen where you live, the ISS is sometimes overhead and high enough to still be in the sunlight. It is highly reflective and very bright, so it is easy to spot if you know when to look. It moves quickly across the sky, which isn’t a surprise considering that the ISS orbits the Earth every 90 minutes and travels at a speed of 17,500 miles per hour. Between moving fast and being wildly bright, it is easy to spot.

To know when to look, go the the NASA site http://spotthestation.nasa.gov/ and click on Location Lookup. Simply enter your location information (Country, State, City, etc.). The site will display information about when the ISS will be visible to you. The main thing, of course, is to find a day and time when you can go outside and look, and then to hope it is not too cloudy during your viewing window.

The results for your local area provide all the information you need to pick a good viewing time. Then you just have to hope it is not cloudy.
The results for your local area provide all the information you need to pick a good viewing time. Then you just have to hope it is not cloudy.
The next important thing is to make sure the ISS will be high enough for you to see. For the “Max Height” column, know that 90 degrees equals directly overhead, so any number above, say, 45 degrees will put the ISS high in the sky. Lower numbers mean the ISS will appear closer to the horizon, so trees or buildings might be in the way and block your line of sight.

Use this graphic to visualize what path the ISS might take in the sky. Credit: NASA.
Use this graphic to visualize what path the ISS might take in the sky. Credit: NASA.
And remember, sight lines work both ways. Since NASA streams live views of the Earth from the ISS, you can very easily go outside to wait for the ISS to appear overhead while watching the live view of Earth from the ISS on a smartphone or tablet computer (if you have a web connection). This allows you to see what astronauts aboard the ISS see if they look down. If it is just past sunset where you live, for instance, look for the line on Earth between night and day to figure out about where you are in terms of east and west.

When the ISS blazes its way across the sky hundreds of miles overhead, you will have achieved a dual, realtime perspective that would have been almost impossible to dream of just a few decades ago. Give it a try!

This picture shows a five-second exposure of the ISS passing just above the Pleiades star cluster on Dec. 27, 2013. The length of the path over five seconds gives you an idea of how fast the ISS moves across the sky.
This picture shows a five-second exposure of the ISS passing just above the Pleiades star cluster on Dec. 27, 2013. The length of the path over five seconds gives you an idea of how fast the ISS moves across the sky. Credit: Clifton Dowell

Two Enduring Star Books for Curious Readers by H.A. Rey

rey_ha_astronomy

Find the Constellations & The Stars: A New Way to See Them by H.A. Rey

It’s not surprising that two astronomy books written by H.A. Rey more than 50 years are still popular. After all, Rey is the same writer/illustrator who, along with his wife, Margret, invented Curious George. The adventures of that famous cartoon monkey have entertained kids by the millions.

H.A. Rey thought the old way of showing constellations made them hard to remember. He thought drawing lines between the stars worked better. He was certainly right when it comes the The Twins.
H.A. Rey thought the old way of showing constellations made them hard to remember. He thought drawing lines between the stars worked better. He was certainly right when it comes the The Twins.
In both his astronomy books, Rey used a new way to draw constellations (or star groups) that he believed made them easier to find in the sky. Instead of placing fancy pictures over the stars to help readers visualize the constellations, he connected the stars like giant dot-to-dots. It works much better in some cases, but not all.

Another thing Rey did in both books is use English names for constellations — for instance, saying “The Bull” rather than “Taurus.” This also works OK, but can be confusing if everyone else is using the old names. As a fan of language, I think part of the fun of new hobbies is learning new words.

Both books are about looking at the sky and learning to find your way around the constellations. Rey writes that the books are meant for people “who want to know just enough about the stars to find the major constellations.” As every backyard astronomer knows, that’s the right place to start.

H.A. Rey had fun making the drawings for Find the Constellations, which he wrote for younger beginners.
H.A. Rey had fun making the drawings for Find the Constellations, which he wrote for younger beginners.
Of the two books, Find the Constellations is intended for younger readers. At only 72 pages, it is thin and features funny cartoons that kids will enjoy. Don’t let the laughs fool you. There is a lot of good information in Find the Constellations and it includes my favorite feature introduced by Rey: star-finding practice exercises!

Looking at star maps with lines or images placed over the constellations is one thing, but it is easy to be bewildered by the actual sky when you look up and see hundred of points of light. So Rey lets you practice by placing identical maps of the sky side-by-side on the page. One version has lines and stars; the other only stars. You can start training your mind to recognize star patterns and to associate them with constellations. And you can do it from the comfort of your favorite chair!

Sometimes trying to make sense of the night sky can be hard. So H.A. Rey lets readers practice comparing the star shapes they have memorized to the points of light they'll see outside.
Sometimes trying to make sense of the night sky can be hard. So H.A. Rey lets readers practice comparing the star shapes they have memorized to the points of light they’ll see outside.
The Stars: A New Way to See Them is also listed as a beginners guide to the stars, but contains more in-depth information about the star and constellations. It has more history and detailed star maps. While the presentation of the material is intended for older beginners, there are still cartoons and humor throughout the book.

What The Stars has that is completely beyond the scope of Find the Constellations, however, is a Part 4 section titled “Some Hows and Whys.”

In Part Four of The Stars,  H.A. Rey walks fearless readers through the geometry behind the nightly show stargazers see in the skies.
In Part Four of The Stars, H.A. Rey walks fearless readers through the geometry behind the nightly show stargazers see in the skies.
This section provides an orderly explanation of how factors such as the tilt of the earth’s axis and the earth’s constant progression around the sun lead to an ever-changing sky. It touches on geometry and demonstrates — again in a straightforward, relaxed style — how everything from navigating the seas to the changing seasons relates to the same factors.

Some people worry that presenting information that is beyond students can be discouraging to them, but I don’t think that is an issue here. In fact, Rey includes a cartoon at the beginning of the section warning that the road is going to be getting a little rougher ahead and that readers “should proceed at their own risk.”

So even if some of the concepts are advanced, daring students will be exposed to the notion that events such as eclipses, seasonal changes, solstices aren’t things that just happen. They happen predictably, for a reason. And they can be understood.

And when you know that, you are already one step closer to grasping the big picture, a big picture that took humankind thousands of years to figure out.

You begin to see yourself standing on the surface of a huge body that is in motion through three dimensional space. You begin to see something amazing about yourself, simply by looking up.

Saturn: Weirdo of the Solar System

This is an artists concept of Cassini during the Saturn Orbit Insertion (SOI) maneuver, just after the main engine has begun firing. The spacecraft is moving out of the plane of the page and to the right (firing to reduce its spacecraft velocity with respect to Saturn) and has just crossed the ring plane. Cassini's close proximity to the planet after the maneuver offers a unique opportunity to observe Saturn and its rings at extremely high resolution. Image Credit: NASA/JPL
This is an artists concept of Cassini during the Saturn Orbit Insertion (SOI) maneuver, just after the main engine has begun firing. The spacecraft is moving out of the plane of the page and to the right (firing to reduce its spacecraft velocity with respect to Saturn) and has just crossed the ring plane. Cassini’s close proximity to the planet after the maneuver offers a unique opportunity to observe Saturn and its rings at extremely high resolution.
Image Credit: NASA/JPL
There is a giant robot circling planet Saturn right now. And this robot is finding weird, amazing things: rainstorms of liquid diamonds, hurricanes bigger than the Earth, ice volcanoes…

But before we get to all that, I should back up a bit and give just a little background on Saturn so you will fully appreciate these new discoveries. Saturn is the sixth planet from the Sun, the farthest planet that can be easily seen without a telescope.

We have always known that Saturn was unusual. Actually, all of the planets were a little unusual to ancient star-gazers. They studied the night sky and saw that almost all the bright dots in the sky moved at the same speed and direction. But they also noticed that five bright dots in the sky moved differently than the stars and constellations. They called these five dots planets (which means wanderer): Mercury, Venus, Mars, Jupiter and Saturn wander among the constellations of the night sky.

Galileo's Drawings of SaturnMore than 500 years ago, in the year 1610, Mr. Galileo found that Saturn was really weird. He was the first person to point a telescope at Saturn and he saw the most incredible sight; Saturn had ears! His drawings looked a bit like Mickey Mouse, with a big circle in the middle and ears poking out on the right and left side.

Another astronomer, Chris Huygens, using a better telescope, found that the “ear” Galileo saw were actually a ring around the planet, just like one you might wear on your finger. Then a guy named Gio Cassini used an even better telescope and could see that the ring was actually multiple rings (at least three) with clear separations between them.

As Saturn advances in its orbit toward equinox and the sun gradually moves northward on the planet, the motion of Saturn's ring shadows and the changing colors of its atmosphere continue to transform the face of Saturn as seen by Cassini. Image Credit: PIA11141 NASA/JPL/Space Science Institute
As Saturn advances in its orbit toward equinox and the sun gradually moves northward on the planet, the motion of Saturn’s ring shadows and the changing colors of its atmosphere continue to transform the face of Saturn as seen by Cassini. Image Credit: PIA11141 NASA/JPL/Space Science Institute
Over the years, we have continued to learn just how weird Saturn is. Saturn has at least 62 moons and dozens of rings. It is the second largest planet, called a “gas giant” which means that it has no rocky surface, it’s all air. Even though it’s huge (760 times bigger than Earth), the gas is really light. If you could put Saturn in a big enough bucket of water, it would float!

Although it is so big, it spins really fast; a day on Saturn is only about 10 hours long. Gas spinning that fast causes tremendously violent storms. Hurricanes larger than whole the Earth rage across Saturn all the time.

Titan's atmosphere makes Saturn's largest moon look like a fuzzy orange ball in this natural color view from the Cassini spacecraft. Titan's north polar hood is visible at the top of the image, and a faint blue haze also can be detected above the south pole at the bottom of this view. (Image Credit: PIA14602 NASA/JPL-Caltech/Space Science Institute)
Titan’s atmosphere makes Saturn’s largest moon look like a fuzzy orange ball in this natural color view from the Cassini spacecraft. Titan’s north polar hood is visible at the top of the image, and a faint blue haze also can be detected above the south pole at the bottom of this view. (Image Credit: PIA14602 NASA/JPL-Caltech/Space Science Institute)
Saturn’s super moon, Titan, is bigger than planet Mercury and has clouds, lakes, rivers and oceans.

By 1990 we had learned a whole lot about Saturn using Earth based instruments (and two very brief flyby missions). But there is just so much you can do from about 1 billion miles away. To learn more, we needed to get up close and personal for an extended time.

In 1997 we launched robot spaceship to do just that. It was named in honor of Mr. Cassini, and carried a smaller robot onboard named after Huygens. Cassini/Huygens was the biggest spaceship NASA had ever built, over 6 tons, big as a school bus. After a six year journey Cassini/Huygens arrived at Saturn and started sending back jaw-dropping details about our sixth planet.

In the next post, I will share some of the secrets of Saturn uncovered by Cassini/Huygens. Be prepared to be amazed!

Fun Phineas Facts
Saturn’s rings disappear every few years! It happened in 1612, completely shocking Galileo. Then to his surprise, the next year they reappeared.

To understand why, you can do a simple experiment. Find a round disc in your home (a quarter, CD, frisbee…) and hold it out at arms length so it looks like a circle. Now tilt it so all you can see is the edge.

Saturns rings are like the disc in your hand. Saturns rings are very wide, but only 30 feet thick. As seen from Earth, Saturns rings wobble, and about every 7 years they are edge on, and basically invisible to us. Then they wobble some more and reappear.

References:

http://www.space.com/48-saturn-the-solar-systems-major-ring-bearer.html

http://saturn.jpl.nasa.gov/

Museo Galileo

Armchair Explorer: Postcards from the Red Planet

mars_rover
Self-Portrait of Mars Rover Curiosity – NASA/JPL-Caltech/MSSS


No matter how far you go, it’s always nice to keep in touch with the folks back home. That’s especially true for a spacecraft that has traveled millions of miles just to send pictures and other information from the surface of Mars back to scientists on Earth.

On June 19, researchers at NASA released their biggest, most detailed picture ever of the surface of Mars. For space fans following the progress of NASA’s Mars rover — named “Curiosity” — as it explores the surface of the Red Planet, pictures are nothing new. One of the great things about NASA is that mission scientists share lots of the data sent back to Earth. Armchair explorers can browse information on the Web — photos, charts, maps, animations and multimedia — alongside scientists around the world.

But the latest picture is NASA’s hugest ever (in camera terms, more than one billion pixels!), which means you can change your viewing angle, move it around and look at different parts of it. When you see something interesting, you can zoom in for closer inspection. See an interesting rock a mile away? No problem. Click and zoom until you get a better look.

It’s as close as you can get to taking a stroll around the surface of Mars.

Billion-Pixel View of Mars Surface with Pan and Zoom

The reason such detail is possible is that the image is made by stitching together nearly 900 pictures taken by Curiosity as it moved around the surface. The pictures were taken over several days in the October and November of 2012. The area photographed includes a windblown patch named “Rocknest,” and extends to Mount Sharp on the horizon. “It gives a sense of place and really shows off the cameras’ capabilities,” said Bob Deen of the Multi-Mission Image Processing Laboratory at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

To access the image and start your own “roving” adventure, go click on the link above.


TERMS

NASA: National Aeronautics and Space Administration, an independent agency of the United States government responsible for aviation and spaceflight.

PIXEL: The basic unit of the composition of an image on a display screen; basically, one single dot that can’t be divided.


SOURCES

PRESS RELEASE: Billion-Pixel View of Mars Comes From Curiosity Rover

WEB: NASA’s Mars Science Laboratory

WEB: NASA’s All About Mars

WIKI: Mars Science Laboratory

WEB: Information on NASA’s Multi-Mission Image Processing Laboratory


PHOTO CREDIT

Image credit: NASA/JPL-Caltech/MSSS “Updated Curiosity Self-Portrait at ‘John Klein'” This self-portrait of NASA’s Mars rover Curiosity combines dozens of exposures taken by the rover’s Mars Hand Lens Imager (MAHLI) during the 177th Martian day, or sol, of Curiosity’s work on Mars (Feb. 3, 2013), plus three exposures taken during Sol 270 (May 10, 2013) to update the appearance of part of the ground beside the rover. The updated area, which is in the lower left quadrant of the image, shows gray-powder and two holes where Curiosity used its drill on the rock target “John Klein.” The portion has been spliced into a self-portrait that was prepared and released in February (http://photojournal.jpl.nasa.gov/catalog/PIA16764), before the use of the drill. The result shows what the site where the self-portrait was taken looked like by the time the rover was ready to drive away from that site in May 2013.

The rover’s robotic arm is not visible in the mosaic. MAHLI, which took the component images for this mosaic, is mounted on a turret at the end of the arm. Wrist motions and turret rotations on the arm allowed MAHLI to acquire the mosaic’s component images. The arm was positioned out of the shot in the images, or portions of images, used in the mosaic.

Malin Space Science Systems, San Diego, developed, built and operates MAHLI. NASA’s Jet Propulsion Laboratory, Pasadena, Calif., manages the Mars Science Laboratory Project and the mission’s Curiosity rover for NASA’s Science Mission Directorate in Washington. The rover was designed and assembled at JPL, a division of the California Institute of Technology in Pasadena.