Ask an Expert

Ask an Expert: Our Solar System REALLY Gets Around
07.01.10
 
Cassini image of softly hued Saturn embraced by the shadows of its stately rings Cassini image of softly hued Saturn embraced by the shadows of its stately rings. (NASA)
Artist concept of Pluto and its moon Chiron Artist's concept of Pluto and its moon Charon. (NASA)
NASA image of a thermal image of Jupiter Red Spot interacting with smaller storms on the planet Thermal image of Jupiter's Red Spot interacting with smaller storms on the planet. (NASA)

More Information
NASA Worldbook: Solar System
Link: NASA's "Summer Science Camp"
The sun is the largest and most important object in our solar system, containing 99.8% of the solar system's mass, or quantity of matter. Among that remaining 0.2% are hot planets, icy moons, asteroid belts, chunks of rock, rings of ice, and over 100 worlds -- including our Earth. The "space" in between is a mesmerizing mix of the push-and-pull of gravity, solar winds, particle radiation, and magnetospheres. Not bad for a mere 0.2%!

On Thursday, July 1, scientist Jonathan Cirtain from NASA's Marshall Space Flight Center answered your questions about our fascinating solar system.

More About Chat Expert Jonathan Cirtain

Dr. Cirtain is an expert in Heliophysics and is the Hinode project scientist as well as the co-investigator on Hinode's onboard X-Ray Telescope. He also has served on the science team for the Atmospheric Imaging Array, an instrument on the recently launched Solar Dynamics Observatory satellite. Dr. Cirtain also has conducted several sounding rocket experiments to test new solar telescope technologies.

He graduated from the University of Memphis in May 2001 with bachelor's degrees in both physics and mathematics. He received a doctorate in physics from Montana State University in 2005, where he was a NASA GSRP fellow and a Harvard pre-doctoral fellow. He has 31 refereed papers, including 10 first-author journal articles.

Dr. Cirtain is an avid swimmer and runner and loves golf. His favorite pastime, however, is spending time with his daughter, Emily.

Chat Transcript
(Moderator Jason): Today's Chat is scheduled to Begin at 3pm ET. Please begin to ask your questions by typing them into the box at the bottom of the screen and clicking the 'Ask' button on the right. We'll begin answering them in about15 minutes. Thanks for your patience.

(Moderator Jason): Hello everyone. Our chat will begin momentarily. Please begin to ask your questions by typing them into the box at the bottom of the screen and clicking the 'Ask' button on the right. We'll begin answering them in just under a minute. Thanks for your patience.

abishek: Hi! Sir, how fast does our solar syster move?

Jonathan: Several thousand km per second around the galactic core. I'm not sure how fast it moves throughout the Universe, in a relative sense.

abishek: How many solar systems are there in the Milky Way galaxy?

Jonathan: There are billions of stars in the Milky Way. It's undetermined how many of those star systems have planets.

abishek: Why isn't Pluto a planet anymore?

Jonathan: NASA doesn't decide if celestial bodies are planets or plantesimals, but the institution that does decide what's called a planet determined that Pluto didn't meet several criteria they use for such a discrimination.

STEVE_IN_COVENTRY_UK: WHAT IS THE DIFFERENCE BETWEEN OUR SUN GOING NOVA AND THE WASP 12 EVENT?

Jonathan: I assume you're asking what would be the difference between the sun within our solar system going nova vs. what will happen in the WASP-12B stellar system when that super-Jupiter-like planet falls into that star. When our sun goes nova, it will balloon out to somewhere between Mars and Jupiter in radial extent and become a red giant until it uses so much internal fuel that it can no longer support the weight of matter in its outer convective envelope. It will then collapse into a white dwarf. That's estimated to happen in about 4 billion years. When the large planet collapses into WASP-12B star -- if we were there to watch it -- we'd see it consumed by fire and then vanish, leaving no trace of its existence.

abishek: What is the surface temperature of Mars, Sir?

Jonathan: Mars is much colder than Earth. Temperatures at the Martian surface vary from as low as about -195 degrees F (-125 degrees C) near the poles during the winter to as much as 70 degrees F (20 degrees C) at midday near the equator. The average temperature on Mars is about -80 degrees F (-60 degrees C).

AkarshValsan: Why are Mercury, Venus, Earth, and Mars called TERRESTRIAL PLANETS and Jupiter, Saturn, Uranus, and Neptune called GAS GIANTS?

Jonathan: They're called terrestrial planets because they have a surface. The gas giants are gas, thus it's not clear that they have a surface.

abishek: Is life possible on Mars?

Jonathan: With NASA, anything is possible. :) Come back next week for our "Extreme Life" Web chat -- that's more in the area of astrobiology.

abishek: Can water be formed on Mars?

Jonathan: Ice has been found on Mars.

abishek: Sir, did you find any new planets in our solar system?

Jonathan: There are still only eight planets in our solar system.

abishek: Sir. what is the temperature of comets?

Jonathan: Their temperatures vary as a function of their distance from the sun, but most of them are ice and metallic ores.

abishek: Sir, do aliens live on Mars or Titan?

Jonathan: Again, check back next week for some more answers about life and its possible forms. (Plus, I've never been to Mars or Titan!)

abishek: Sir, which planet is spectacular to see?

Jonathan: My favorite is Saturn.

AkarshValsan: Why do scholars say, "The further the planets from the Sun, the more spaced out they are?"

Jonathan: When the solar system coalesced out of dust and gas, the distance radially from the center of mass of the solar system for concentrations within this dusty gas cloud attracted more and more matter as a function of time. As the density of these objects increased, the gravitational pull they exerted on other bodes nearby also increased, drawing all of this in together. These large conglomerations of materials then followed Keplerian, effectively, orbits about that central gravitational well. Eventually, all of the mass in a particular circumferential area was swept up by these large masses, thus forming planets. The further out they are, the less collisions with other massive objects, so they're free to grow to larger size.

abishek: Sir, how is Venus both a morning and an evening star?

Jonathan: Time is arbitrary. In fact, Venus never climbs to the zenith so it's not far off the horizon in the morning or the evening depending on the relative position of Venus to Sun and Earth to the Sun, annually.

abishek: Sir, is there anything that is more spectacular for us to know?

Jonathan: There is always more to know. :)

Ediz_Celik: How did our solar system begin?

Jonathan: In a previous post, I explained roughly how planets form. Here's a recap: When the solar system coalesced out of dust and gas, the distance radially from the center of mass of the solar system for concentrations within this dusty gas cloud attracted more and more matter as a function of time. As the density of these objects increased, the gravitational pull they exerted on other bodes nearby also increased, drawing all of this in together. These large conglomerations of materials then followed Keplerian, effectively, orbits about that central gravitational well. Eventually, all of the mass in a particular circumferential area was swept up by these large masses, thus forming planets. The sun formed at the center of this planet-forming exercise when sufficient mass coalesced with sufficient density to initiate fusion.

Ediz_Celik: How do you calculate the distance of a planet from the sun? And how do you calculate the mass of a planet?

Jonathan(: Kepler used Newtonian laws of physics, in particular the Newtonian law for gravity. F=MA to determine the orbits and rough masses for all of the planets through Saturn exclusing Mercury. He did this by making precise measurements of the time of transit of the panets across the night sky. In doing so, he was able to determine how long it would take that planet to transit the sun, given his precise and accurate calculation for the distance from the Earth to the sun.

Ediz_Celik: What source of the Jupiter's Red Spot?

Jonathan: It's an enormous storm. I'm not sure anyone knows where it came from or why it's lasted so long.

rahulr96: Does the Oort Cloud end the solar system or does it go out farther? Where does it really end?

Jonathan: The heliosphere ends at the heliopause, which is roughly on the other side of the Oort cloud. In a few years, we'll know where the edge of the solar system is, as Voyager will exit the solar system and tell us.

abishek: Sir, is Venus hotter than the Earth's core?

Jonathan: The surface of Venus isn't hotter than the Earth's core. The Earth's core is primarily a liquid metal, generally 2,000 or so Kelvin. The surface of Venus is 10x cooler.

Lindsay: I've heard that Jupiter is actually a failed star. Does our solar system behave at all like a binary star system -- and if so, how? Thx!

Jonathan: Jupiter doesn't have sufficient mass -- nor is it likely that it ever did -- to go nuclear. The mass in our solar system is so widely distributed from the sun to the edge of the heliopause that comparison to a binary system isn't specifically appropriate.

CraigNASA: About how big is our solar system?

Jonathan: It's about a light year across, or roughly 50,000 Earth-sun distances.

abishek: Sir, how are you able to manage many questions at a same time?

Jonathan: I type really fast! :)

calvin: Greetings. Is it possible for there to be a planet similar to Earth in a perfectly simetric orbit (i.e. always behind the Sun from Earth's point of view) that may have thus remained undetected?

Jonathan: No, because Earth's orbit is an ellipse.

abishek: Thanks, Sir.

Jonathan: You're welcome, abishek.

CraigNASA: How many known plannets are in our solar system?

Jonathan: Currently, still eight.

longsheryl: How hot is our sun?

Jonathan: The surface temperature is roughly 5,600 degrees Celcius. In the core of the sun, where fusion happens, the temperature (if there is such a thing) is 100 million degrees Celcius. The sun's atmosphere is also a million degrees or so.

taaniagirgla: Why does the moon's gravity only have an effect on our water and nothing else?

Jonathan: The moon affects more than just water. In fact, the shape of the Earth changes as a function of the moon's distance, thus causing the tides. It also changes the shape of our atmosphere.

CraigNASA: How fast does the sun rotate?

Jonathan: A day on the sun -- a strange concept, to be sure! -- is 27 days. To put it differently, it takes 27 days for the sun to rotate relative to a fixed position.

astroivy: How long have you been working at NASA? And what's your favorite part of your job?

Jonathan: Three years, and launching rockets is my favorte part!

AkarshValsan: People say that without the sun's energy, life would not exist.But we all know there are stars bigger than the sun, such as Antares. Can any other stars take a role like the sun and support life like Earth?

Jonathan: Given that there are no other stars close enough to the Earth to deposit the amount of energy required to fuel photogsynthesis and other methods for conversion of energy into consumable units for life to use, without our sun -- there would be no "us."

(Moderator Jason): We're working to get through all of the great questions you've asked us. Keep them coming! To submit your own question, please type it in the box at the bottom of the window and click the 'Ask' button on the right side of the box. Thanks for your patience as we answer your questions.

taaniagirgla: Why do only the gas planets have rings?

Jonathan: In fact only two of the gas giants have rings: Saturn and Uranus. Eventually the rings from these planets will collapse or fall into the planet and they'll look just like Jupiter. Presumably, at some point in its past, Jupiter also had rings. However, Jupiter's many moons and self-gravitation consumed these rings with time.

abishek: Sir , are the Arctic poles the best place for observation of planets?

Jonathan: No, the equator is. It has the longest period of constant viewing relative to the heliospheric ecliptic. Also, the Arctic has days that last for months, and not so much land.

AkarshValsan: WHY DO SCHOLARS BELIEVE THE SOLAR SYSTEM WAS FORMED FROM AN PHOTO PLANETARY DISC?

Jonathan: Scholars do not believe the solar system formed from a proto planetary disc. They know it. :) We've observed stellar and planetary formation in various phases both within our own galaxy and other galaxies. Hubble has made many of these discoveries.

CraigNASA: Do you think we will ever be able to explore things out of our solar system?

Jonathan: Yes, we already do, remotely using telescopes over the entire electromagnetic spectrum. Also, Voyager is leaving the solar system soon and frequently reports back.

Lindsay: So the universe is expanding -- does that mean our solar system is expanding, too?

Jonathan: No, our solar system's size is dictated by a convolution of the gravitational pull of the massive black hole at the center of the galaxy, gas pressure, and external radiative and gas pressure from surrounding material within the galaxy.

abishek: Sir, are there any interesting websites for us to know more on planets?

Jonathan: Yes. http://www.nasa.gov/missions/index.html and http://www.nasa.gov/worldbook/index.html are good places to start.

sanema: Hello I'm Neify from Colombia, I just want to know if it is true that pluto is no longer a planet, and if it is, which were the reasons in ordr to arrive to that conclusion?

Jonathan: NASA doesn't decide if celestial bodies are planets or plantesimals, but the institution that does decide what's called a planet determined that Pluto didn't meet several criteria they use for such a discrimination. Size does matter. :)

Ediz_Celik: Thanks for answering our questions :)

Jonathan: You're very welcome. :)

AkarshValsan: Why did Galileo say that Jupiter has four little stars circling around it? Was it true?

Jonathan: Galileo didn't call them stars. In fact, in Italian, he coined the phrase "moon."

abishek: Sir, are there black holes in our solar system?

Jonathan: I hope not!

CraigNASA: When did scientists discover the red spot on Jupiter?

Jonathan: Galileo discovered it in the 1600s.

(Moderator Jason): We're still working on answering all the great questions you've asked. If you haven't seen yours yet, give us a few minutes to get to all of your questions. To submit your own question, please type it in the box at the bottom of the window and click the 'Ask' button on the right side of the box. Thanks for your patience as we answer your questions.

abishek: Sir, does Uranus have rings like Saturn?

Jonathan: No, Saturn's rings are inclined relative to the direction Saturn rotates about the sun of a few 10s of degrees. Uranus' rings are orthogonal to the direction of rotation of Uranus about the Sun. This is because Saturn rotates on it s axis in the plane of rotation about the sun whereas Uranus rotates on its axis in a place 90 degrees offset from the plane of rotation about the sun.

abishek: what do Saturn's rings consist of?

Jonathan: Small particles of dust.

AkarshValsan: Do every planets have Gravitational Pull?

Jonathan: Yes, they do. It's proportional to their mass.

djvexd: Don't you mean Pioneer will exit the solar system?

Jonathan: No, Voyager.

abishek: Sir, why does Mercury lose atmosphere more often?

Jonathan: Mercury actually has no atmosphere.

solarnut: Any missions planned to study the Sun?

Jonathan: There are a fleet of currently operating missions to study the sun. These include the Solar Dynamics Observatory (SDO), Hinode, RHESSI, the Solar and Heliospheric Observatory (SOHO), STEREO, PROBIS-B, and in the future, Solar Orbiter and Solar Probe. This last one, Solar Probe, will venture the last place in our solar system humankind has yet to explore: the solar atmosphere.

redplanet: Io is continually getting squeezed by Jupiter, causing it to spew lava from volcanoes all over the planet. Can this last forever? Or will Jupiter eventually tear Io apart?

Jonathan: It can't last forever. Jupiter will eventually beat Io down.

AkarshValsan: What is heliosphere?

Jonathan: The heliosphere is the region of space where the sun and the solar output dominate. It extends from the sun to well past Uranus and the Oort Cloud. It's balanced by the outward pressure of the solar wind and pressure from surrounding gas clouds within the galaxy.

taaniagirgla: Where is hydrogen created from?

Jonathan: Hydrogen isn't created any longer. Baryonic material formed a few 100,000 years after the Big Bang when quarks coalesced into protons and neutrons. There will never be any more.

AkarshValsan: Why is Venus hotter than Mercury?

Jonathan: The greenhouse effect.

CraigNASA: How long would it take to fly across our Solar System?

Jonathan: It would depend on your vehicle. In a Fiat, it would take about 200,000 years. In the Space Shuttle, it would take about 16,000 years. In the Star Trek Enterprise, with full impulse power, it only takes a matter of days. :)

abishek: Sir how do you calculate the length of the solar system?

Jonathan: Kelperian dynamics.

taaniagirgla: Why does only the moon affect our tides? Why not say the sun, which has a much greater mass?

Jonathan: Only the moon is in orbit about the Earth.

abishek: Sir how will you Find the edge of the solar system?

Jonathan: Voyager will tell us.

AkarshValsan: Which is the nearest star to the Earth?

Jonathan: The Sun. :)

sanema: I'm a teacher and I need to prove to parents the information about the existence of just eight planets, where can I send them or is it possible that you let me know about a site where parents can search and confirm the information. Unfortunately, there are too many who still do not believe, and keep on considering pluto as a planet. Thanks a lot for your time and your answer.

Jonathan: Try this link as a good source for that: http://www.iau.org/public/pluto.

longsheryl: How many times does Earth go around?

Jonathan(: It goes around once per day on its axis, once per year around the sun, and once every 17,500 years about the galactic core, approxiately.

AkarshValsan: Is Big Bang theory responsible for the expansion of Solar System?

Jonathan: The Big Bang, a theory about the origin of the universe, has already happened. It may be responsible in part for the expansion of the universe. But, the solar system volume doesn't appear to be changing appreciably.

abishek: Sir, how do you find other galaxies in the universe?

Jonathan: By using telescopes.

solarnut: How does solar wind affect satellites in orbit?

Jonathan: It produces drag, slowing the satellite down. Once the satellite loses angular momentum as a result it begins to also lose altitude.

Taania: Can we keep typing new questions up even though the previous ones have not been answered yet?

Jonathan: Yes

(Moderator Jason): We're still working on answering all the great questions you've asked. If you haven't seen yours yet, give us a few minutes to get to all of your questions. To submit your own question, please type it in the box at the bottom of the window and click the 'Ask' button on the right side of the box. Thanks for your patience as we answer your questions.

longsheryl: Sir how hot is our planet sun?

Jonathan: The Sun isn't a planet. :) Our sun, on its surface, has a temperature of roughly 6,000 C.

Taania: Why does a star die when is starts to create iron?

Jonathan: Iron is the last element where fusion can occur within a star. For elements with more protons in their nucleus, too much energy is required for fusion to create them. It's called an endothermic process. When a star runs out of fuel, it dies. Thus, when a star has converted all of its hydrogen into heavier elements, it dies.

solarnut: What happens in the transition region of the sun?

Jonathan: The transition region is a thin volume within the solar atmosphere sandwiched between the chromosphere and corona. It's a region where the temperature rapidly increases from 20,000 C to 1 million C and the density decreases a thousandfold, too.

solarnut: What is the aurora?

Jonathan: As the solar wind is trapped within the Earth's magnetosphere, electrons and protons are accelerated along the Earth's magnetic field and whenever charged particles are accelerated, they emit photons. This is the aurora.

LINDSAY....cant_touch_this: Do you know all of this off the top of your head? or do you have sources to glean info off of?

Jonathan: Yes. :)

AkarshValsan: Sir why is the corona white in colour?

Jonathan: The corona appears to be white during a total eclipse because of scattering. However, the solar corona emits electromagnetic radiation in every energy range from radio to gamma.

abishek: Sir how is the sun responsible for tides in the earth?

Jonathan: It's not -- that's caused by the moon.

nailson_BRA: How would our oceans behave if we had 2+ moons?

Jonathan: It would depend on the size and location of the moons relative to the Earth. How would you behave if you had three sisters? :)

AkarshValsan: What type of galaxy is milky way?

Jonathan: A spiral galaxy.

longsheryl: Sir where do you work Texas or Florida?

Jonathan: In Alabama.

CraigNASA: What was your favorite rocket that has been launched in your career, sir?

Jonathan: A Delta Heavy.

(Moderator Jason): We're still working on answering all the questions you've asked. If you haven't seen yours yet, give us a few minutes to get to all of your questions. To submit your own question, please type it in the box at the bottom of the window and click the 'Ask' button on the right side of the box. Thanks for your patience as we answer your questions.

Taania: Why will our sun shrink when it starst to fuse carbon? Isn't energy still being released in nuclear fusion when carbon is being created, thus, kepping the balance between outward pressure and gravity?

Jonathan: The sun will shrink because the outward radiative pressure resulting from the rate of fusion in the core is insufficient to withstand the inward pull of gravity. As part of the C-N-O fusion evolution, the rate of photonic output relative to each fusion event decreases with atomic weight.

CraigNASA: What gives the sun its color?

Jonathan: Color is proportional to surface temperature. The sun's surface is 5,600 C or so, and that's yellow. If it were 10,000 C, it would be blue.

longsheryl: Sir, how old is our planet?

Jonathan: Four billion years old, as a guess. I've only been around about a billion times less long. :)

CraigNASA: Is the sun considered a gas giant?

Jonathan: No. It's an average K.

Taania: Why does our magnetic field keep out solar wind but not meteors?

Jonathan: Generally meteors have a substantial mass-to-charge ratio. In fact, most solar wind content is a plasma. A plasma in the presence of a magnetic field directly interacts, and often the wind is reflected off the magnetosphere and back into interplanetary space. Meteors aren't reflected by the magnetic field because they don't "know it's there."

JohnDoe: Could a solar flare or coronal mass ejection ever be big enough to reach the Earth?

Jonathan: In fact they reach the Earth all the time. CMEs cause the aurora. In 1988 a large solar flare caused such a back EMF along the Canadian power grid in Quebec that the power grid failed and people were without electricity for days. So the question is not really if they're big enough, but if they're directed toward us often. The answer to that is also "fairly frequently." In solar physics, the term is geoeffective eruption.

LINDSAY....this_is_ur_conscience: What is the nearest black hole to us?

Jonathan: The nearest black hole that I'm aware of is in our galaxy's core.

AkarshValsan: Olympus Mons is on what planet?

Jonathan: Mars

Matt: What are micro black holes and how common are they?

Jonathan: Micro black holes are very small. They're theoretical and their existence in Nature is as-yet confirmed.

Taania: What are the basics of how the kinetic energy of the liquid iron in the core of our planet converts to magneticenergy and, thus, creates our magnetic field? I mean I know that our magnetic field comes form the liquid iron in our core, but what are the basics of how the field is created?

Jonathan: The liquid core of the Earth is a rotating plasma. Faraday's Law states that any charge in motion generates a magentic field. So, the charged liquid ball rotating in the center of the Earth is generating a large magnetic field in a direction requisite with the right-hand rule: thumb in the direction of rotation, curl your fingers, and that' s the direction of the magnetic field.

abishek: Sir, will space dust affect our rockets and satellites?

Jonathan: Yes. Dust in space creates drag for satellites in orbit about the Earth. Dust in your rocket or in your satellite impacts performance.

JohnDoe: Since the sun produces energy, could that become more of a power source beyond solar panels?

Jonathan: We actually use solar power for solar sails. Eventually, I imagine we'll use such technology as engines for spacecraft.

JohnDoe: Is there going to be a time when the sun will ever burn out? If so, when?

Jonathan: Yes, in about 4 billion years.

JohnDoe: The sun will grow larger when it gets older, right? Will it ever move closer to Earth?

Jonathan: Yes, eventually it will become a red giant and likely absorb the Earth.

AkarshValsan: Why is it impossible to see Venus's surface from Earth? :-)

Jonathan: Its atmosphere is too thick.

Ediz_Celik: Will the moon leave Earth one day?

Jonathan: Yes.

kid31: Can we look into the opposite of the big bang at the outher edge of the universe and what is out there?

Jonathan: No. On the opposite side of the Big Bang, there are no photons and thus nothing to see with. Matter and energy only exist within the Universe.

CraigNASA: Sir, What do you think is the most important peice of imformation that the SDO brought back?

Jonathan: SDO is a new mission with many exciting discoveries. One of my favorites is the generation of wave phenomena associated with flaring active regions.

(Moderator Jason): We've got about ten minutes left in today's chat and time to get answers for a few more questions. Jonathan is working hard to get through all the questions in the queue and answer as many as possible. Thanks for your patience.

abishek: Sir, do satellites also have gravitational pull?

Jonathan: Anything that is matter has a gravitational pull.

mastermitz: What might be the origin of perturbations in the Oort cloud that would send a comet to the inner solar system for the first time?

Jonathan: Passage of the heliosphere within a more dense or rarified region of the galaxy may cause gravitational perturbation in the shape of the heliosphere. This would change the dynamics of the volume of the Oort cloud and random collisions of the bodies within the cloud statistically may generate new comets.

Matt: What are solar winds?

Jonathan: In a seminal paper in 1958, Eugene Parker demonstrated theoretically from a magnetohydrodynamic basis that the pressure and temperature of plasma at the solar surface would drive mass away from the sun at a constant rate along magnetic field lines into the heliosphere.

CraigNASA: What is the "Green House Effect" sir?

Jonathan: Increases in particular types of gasses like carbon dioxide and hydroflurocarbons generate layers in the atmosphere that reflect heat. When radiation from the sun passes through one of these layers and heats the ground, the heat is thus trapped.

Taania: So, if no more hydrogen, then soon no more stars? That's a scary thought! What will be left in our universe then?

Jonathan: Eventually, this is true. Dark matter will be left.

(Moderator Jason): We've got time for just a few more questions...

CraigNASA: I want to work for Mission Control at NASA when I get older, What can I do now that could help me, sir?

Jonathan: Study math and science!

CraigNASA: Do you think that astronuats will EVER be able to go to the sun, sir?

Jonathan: No. They'll never go to the sun.

rahulr96: Can you work for NASA if you live in any state...say New Jersey ;)?

Jonathan: NASA has probably hired people from New Jersey. But there's no NASA center in NJ. You'd have to move. :)

Taania: Is it hard to geta job at NASA?

Jonathan: Well, it IS rocket science. :)

(Moderator Jason): Thanks to everyone who posed questions today. We hope you found this to be very interesting and that you got some great answers. And a big thanks to Jonathan for taking some time to sit down with everyone and answer your questions! Have a great weekend.
 
 


Janet Anderson, 256-544-0034
Marshall Space Flight Center, Huntsville, Ala.
Janet.L.Anderson@nasa.gov