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    Two colleagues and I went out for lunch today and one of them asked what the word 'geosynchronous' meant. It's a term to describe the orbit of a satellite that appears to be stationary over the Earth, we answered, and then we all three pushed our imaginary glasses up the bridge of our noses.

    We were half right with our explanation. Geosynchronous is a term used to describe the orbit of a satellite that moves at the same speed that the Earth rotates about its axis. However, because this orbit can be titled over the Earth like an angel with a lopsided halo, the satellite can appear to move north and south in the sky throughout the day, though it always stays over the same line of longitude.

    A geostationary orbit, the one we often think of when we hear the word "geosynchronous," is when a satellite is in a geosynchronous orbit over the equator. In this kind of orbit, the satellite appears to be stationary over the Earth.

    In the same way that a square is always a rectangle but a rectangle isn't always a square, a satellite in a geostationary orbit is always in a geosynchronous orbit, but not the other way around.

    Communications satellites are often in geosynchronous orbits so that the antennas of ground stations can remain constantly pointed at the same spot in the sky. Weather satellites are also common geostationary orbiters so that they can constantly monitor the same spot on the Earth.

    Back to our lunch discussion: How fast, we wondered over our kebabs, would a geostationary satellite have to be moving to stay stationary in the sky? The space shuttle orbiter, we know, orbits at around 8,000 meters per second (18,000 miles per hour) but it does a complete orbit in about 90 minutes. Would a geostationary satellite be going faster or slower?

    To find out, I did a little math. To find the speed of an object, we divide the distance it crosses by the time it takes to cross that distance. (Speed equals distance divided by time.) The speed of the Earth's rotation is 465 meters per second, which we get from dividing it's circumference, 40,075 km, by 86,4000 seconds (the number of seconds in a day).

    To find the circumference of the geostationary satellites' orbit, we add the radius of the Earth, 6,378 km, to the height of the satellite's orbit, 35,786 km, (which we obtained from Wikipedia) to get 42,164 km. We then multiply that number by 2*pi (the equation for the circumference of a circle is the circle's radius times 2*pi) to get 264,924 km.

    Because the satellite has the same orbital period as the Earth's rotation, we divide the orbital circumference by 86,400 seconds and we get 3,066 meters per second (or 6,858 miles per hour) -- quite a bit slower than the space shuttle. Still, that's way faster than the average bear.
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    “How many of you think you know what the gap is going to be [in] American capability to take things to low Earth orbit between the end of shuttle and the onset of the next American capability?" NASA Administrator Charles Bolden asked a packed room at the University of Maryland's Samuel Riggs IV Alumni Center on Thursday morning.

    He opened the first NASA Future Forum of 2011 with a speech saying that though the shuttle days are over, NASA still has a future.     What remained unclear that morning, though, was what exactly that future might be.

    "It’s in terms of months," Bolden said. "We will be flying American vehicles to the International Space Station in less time than it took us to recover from Challenger or Columbia."

    The American space program won't have to rely on the Russians, the Europeans or the Japanese, Bolden said, though of course we still want to work closely with our international partners. Private companies like Orbital Sciences and Space X will take over the responsibility of access to low Earth orbit for Americans, with Space X possibly bringing cargo to the ISS by February.

    The administrator of NASA was all smiles as he spoke about the future of NASA to a room of attendees gathered to hear and discuss advances in science, technology and exploration that will help bolster NASA's future and inspire a whole new generation of explorers.

    Though Bolden sounded optimistic, the news about delivering cargo to the ISS wasn't entirely convincing and the first panel of the day quickly digressed into the same old NASA rhetoric, taking the wind out of Bolden's sails. Rhetoric about the glory of innovation and the spirit of dreaming, about eating your vegetables and studying hard so you, too, can be a John Glenn or a Sally Ride (even though the future of manned spaceflight is, at best, questionable right now, but don't focus too much on that!). Sadly, once again, NASA missed the opportunity to remind the world (and itself) that its missions are about more than manned spaceflight.

    When it comes to the future, science - real science - is what NASA needs to get back to, and the organization needs to find a way to make it fun and interesting and sexy. Relying on the glory of the Apollo days (though they were glorious, indeed) isn't enough any more.

    The second panel focused on technology and innovation and the one speaker whose rhetoric sounded fresh was a man the moderator introduced as the panel's "token scientist." Ralph McNutt, Jr., is a physicist at The Johns Hopkins University Applied Physics Laboratory. The list of NASA probes he has worked on is long and envious. (How can one person keep up with so many acronyms?)

    [Ralph McNutt, right, speaks while David Barbe, left, listens.]

    McNutt spoke about two probes whose futures were bright and promising. The first was the ongoing MESSENGER mission to Mercury. MESSENGER is the first spacecraft to ever orbit the Solar System's innermost planet and has already corrected something kids were taught in grade school.

    “Mercury is very definitely not like the Moon; It’s much more like the other terrestrial planets in the Solar System.” Innovation, combined with technology, McNutt said, was key to making the MESSENGER discovery possible. The spacecraft uses a gamma ray spectrometer to examine the planet's surface. The spectrometer must be very cold to work properly, though, not a simple requirement to meet for an instrument in orbit around the Solar System's hottest planet.

    [Though Mercury's surface looks a lot like the Moon, the MESSENGER mission has shown that the planet is more like its terrestrial planet siblings. In the three months it has been in orbit around Mercury, MESSENGER has snapped around 40,000 photos of the planet. Photo credit: NASA/MESSENGER.]

    Ultimately, a soda can-sized cryogenic cooler was taken from air-to-air missiles to be used on the spacecraft. The small cooler was only supposed to last a few years at best (nowhere near good enough for a space mission) but was improved upon for MESSENGER. That type of "innovation on the fly" helped to open a whole new chapter on our understanding of the inner part of the solar system, McNutt said.

    He then spoke about a future mission scientists are working to make a reality: Solar Probe Plus. This probe would visit the outer atmosphere of our Sun - the place where the disruptive solar wind that messes with our Blackberry devices and our satellite signals originates.

    “The problem is, we still don’t understand the physics of how exactly the Sun makes the solar wind and why the corona is so hot," McNutt said. To make that kind of research happen, we'll need new innovators and new technology. This rhetoric was inspiring. Figuring out the mysteries of the Sun and coming to the rescue of crackberry users worldwide are dreams that modern kids can get behind.

    The NASA spokespeople said over and over again during the morning of the forum that they want to reach out to academia and the public for ideas and innovation, and they encourage the public to reach out to NASA. But if the agency really wants to attract people, they need to ditch the old Apollo-era glamor and focus on a new-school allure. NASA needs a new hero. A Carl Sagan. A Neil deGrasse Tyson. A Mythbuster. One who will champion good, old-fashioned science.
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      ...Read On

    “How many of you think you know what the gap is going to be [in] American capability to take things to low Earth orbit between the end of shuttle and the onset of the next American capability?" NASA Administrator Charles Bolden asked a packed room at the University of Maryland's Samuel Riggs IV Alumni Center on Thursday morning.

    He opened the first NASA Future Forum of 2011 with a speech saying that though the shuttle days are over, NASA still has a future.     What remained unclear that morning, though, was what exactly that future might be.

    "It’s in terms of months," Bolden said. "We will be flying American vehicles to the International Space Station in less time than it took us to recover from Challenger or Columbia."

    The American space program won't have to rely on the Russians, the Europeans or the Japanese, Bolden said, though of course we still want to work closely with our international partners. Private companies like Orbital Sciences and Space X will take over the responsibility of access to low Earth orbit for Americans, with Space X possibly bringing cargo to the ISS by February.

    The administrator of NASA was all smiles as he spoke about the future of NASA to a room of attendees gathered to hear and discuss advances in science, technology and exploration that will help bolster NASA's future and inspire a whole new generation of explorers.

    Though Bolden sounded optimistic, the news about delivering cargo to the ISS wasn't entirely convincing and the first panel of the day quickly digressed into the same old NASA rhetoric, taking the wind out of Bolden's sails. Rhetoric about the glory of innovation and the spirit of dreaming, about eating your vegetables and studying hard so you, too, can be a John Glenn or a Sally Ride (even though the future of manned spaceflight is, at best, questionable right now, but don't focus too much on that!). Sadly, once again, NASA missed the opportunity to remind the world (and itself) that its missions are about more than manned spaceflight.

    When it comes to the future, science - real science - is what NASA needs to get back to, and the organization needs to find a way to make it fun and interesting and sexy. Relying on the glory of the Apollo days (though they were glorious, indeed) isn't enough any more.

    The second panel focused on technology and innovation and the one speaker whose rhetoric sounded fresh was a man the moderator introduced as the panel's "token scientist." Ralph McNutt, Jr., is a physicist at The Johns Hopkins University Applied Physics Laboratory. The list of NASA probes he has worked on is long and envious. (How can one person keep up with so many acronyms?)

    [Ralph McNutt, right, speaks while David Barbe, left, listens.]

    McNutt spoke about two probes whose futures were bright and promising. The first was the ongoing MESSENGER mission to Mercury. MESSENGER is the first spacecraft to ever orbit the Solar System's innermost planet and has already corrected something kids were taught in grade school.

    “Mercury is very definitely not like the Moon; It’s much more like the other terrestrial planets in the Solar System.” Innovation, combined with technology, McNutt said, was key to making the MESSENGER discovery possible. The spacecraft uses a gamma ray spectrometer to examine the planet's surface. The spectrometer must be very cold to work properly, though, not a simple requirement to meet for an instrument in orbit around the Solar System's hottest planet.

    [Though Mercury's surface looks a lot like the Moon, the MESSENGER mission has shown that the planet is more like its terrestrial planet siblings. In the three months it has been in orbit around Mercury, MESSENGER has snapped around 40,000 photos of the planet. Photo credit: NASA/MESSENGER.]

    Ultimately, a soda can-sized cryogenic cooler was taken from air-to-air missiles to be used on the spacecraft. The small cooler was only supposed to last a few years at best (nowhere near good enough for a space mission) but was improved upon for MESSENGER. That type of "innovation on the fly" helped to open a whole new chapter on our understanding of the inner part of the solar system, McNutt said.

    He then spoke about a future mission scientists are working to make a reality: Solar Probe Plus. This probe would visit the outer atmosphere of our Sun - the place where the disruptive solar wind that messes with our Blackberry devices and our satellite signals originates.

    “The problem is, we still don’t understand the physics of how exactly the Sun makes the solar wind and why the corona is so hot," McNutt said. To make that kind of research happen, we'll need new innovators and new technology. This rhetoric was inspiring. Figuring out the mysteries of the Sun and coming to the rescue of crackberry users worldwide are dreams that modern kids can get behind.

    The NASA spokespeople said over and over again during the morning of the forum that they want to reach out to academia and the public for ideas and innovation, and they encourage the public to reach out to NASA. But if the agency really wants to attract people, they need to ditch the old Apollo-era glamor and focus on a new-school allure. NASA needs a new hero. A Carl Sagan. A Neil deGrasse Tyson. A Mythbuster. One who will champion good, old-fashioned science.
      ...Read On

    Washington (AFP) Dec 30, 2010
    NASA said Thursday it has found four more small cracks on the metal supports of the shuttle Discovery's external fuel tank, as the shuttle and external tank undergo further X-ray testing before its final space mission next year. Repairs would be made to the cracks in a similar fashion to the cracks discovered after the November 5 launch attempt, the National Aeronautics and Space Administration said in a stat www.space-travel.com


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    Moscow, Russia (RIA Novosti) Dec 22, 2010
    Russia's Mission Control is preparing to adjust the orbit of the International Space Station (ISS) on Wednesday by raising it 4.2 kilometers (2.6 miles). The readjustment is necessary to ensure the best conditions for the docking of Russia's Progress M-09M space freighter and the U.S. Discovery's final mission to the orbital station before the veteran space shuttle is removed from future s www.space-travel.com


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