National Aeronautics and Space Administration

A visualization of the sodium "exosphere" around Mercury courtesy of Matthew Burger at NASA's Goddard Space Flight Center.



In the space exploration racket, there is no sweeter word than “first.” And so it was last night that a NASA spacecraft made an important First in planetary exploration:

“NASA’s MESSENGER spacecraft successfully achieved orbit around Mercury at approximately 9 p.m. EDT Thursday. This marks the first time a spacecraft has accomplished this engineering and scientific milestone at our solar system’s innermost planet.”


We flung the Mariner 10 spacecraft past Mercury in fly-by missions in 1974-75. And Messenger itself did three fly-bys as it got into position for the final “orbital insertion.” Now it is the first space probe to park in orbit around the first rock from the sun.





Rosemary Killen, a researcher at Goddard, is one of the many scientists who will reap rewards from this so-far spectacularly successful mission. Her target is the thin “exosphere” of sodium, potassium, and calcium knocked off Mercury’s barren rocky surface by the “solar wind” streaming from the sun.

If you want all the scientific details, read a short explanation below by Rosemary Killen about her work And also read about some of the instruments that Goddard scientists and engineers helped to put on the spacecraft.

Otherwise, enjoy the slide show of Messenger images, 2004-2011, and an informative video by Tom Watters (below), a geologist in the Center for Earth and Planetary Studies at the Smithsonian Institution. He explains the goals of Messenger.





Rosemary Killen:

“I am a Participating Scientist on the MESSENGER mission and a member of the MASCS (Mercury Atmospheric and Surface Composition Spectrometer) team. MASCS is a spectrometer covering ultraviolet, visible, and near-infrared wavelengths. The MASCS ultraviolet and visible channel is designed primarily to observe the exosphere, or the very tenuous atmosphere about Mercury, by scanning over selected, diagnostic wavelength ranges.

“Our goals are to determine the composition of the exosphere (which is only partially known at present), and, over the mission lifetime, to determine its spatial and temporal variability. We do this by observing emission lines from atoms (and a few ions) in the exosphere above Mercury’s surface. In so doing we hope to determine the processes that eject atoms from the surface into the exosphere and that lead to the loss of material from the Mercury system.

“Important factors include the relationships among the exosphere and the solar ultraviolet flux, the solar wind and interplanetary magnetic field, and the planet’s intrinsic magnetic field. We hope to be able to determine the effects (if any) of meteor streams that may intersect Mercury’s orbit.

“One intriguing question is the nature of the deposits seen by Earth-based radar (specifically that at the Arecibo Observatory) in polar craters on Mercury, and what that tells us about the sequestration of volatiles. The visible and near-infrared channel of MASCS is primarily designed to measure the reflectance spectrum of the surface in order to determine the mineralogy of surface materials. Ultimately the goal is to unravel the history of the planet: its origin and evolution to the state it occupies today.”

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.



Marc Kuchner is an astrophysicist at Goddard Space Flight Center who studies planetary systems around other stars. As he explains in this video, the trouble is that when you point a telescope — even one as powerful as the Hubble Space Telescope — at a star with a planetary system, you can’t see the actual planets very clearly. At best you see a glowing dot.

But what you CAN see very clearly is the thin dusty disk that occupies a vast volume of space around the star. Our solar system has one, too: It’s called the zodiacal cloud.

Marc and his students — most notably, Christopher Stark, now at the Carnegie Institution for Science in Washington, D.C. — have developed computer simulations of planetary dust. This is what the simulations show: Although it may be some time before we have a space telescope powerful enough to directly image the face of an alien planet, we should be able to detect the presence of planets by the effects they have on dusty disks. Most likely those planetary telltales will be structures such as rings and dimples.

Want to know more about dust simulations? See a previous gogblog post and the computer visualization below for the details.

By the way, when Marc mentions during the interview that there are “about 400 planets known,” it was accurate. But since this interview was recorded, the count has risen to 500!



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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.

Hey kids — got a science report due on the solar system? Do I have a video for you: a guided tour of the inner rocky planets by Goddard’s James Garvin.

Chief Scientist of NASA’s Goddard Space Flight Center, Dr. Jim Garvin, takes us on a journey of Earth, the moon, and our neighboring planets. Why does space matter? Why is exploring the inner solar system so crucial? Where will humans venture to next? In this video lecture, Dr. Garvin answers these questions and discusses NASA’s past, present, and future of discovery on our nearest neighbors in the solar system.

Click the image above to see the entire 55-minute presentation on Blip TV. This version, compressed to play in a continues clip, is a little grainy. That short-changes you a bit on the fantastic computer simulations and images packed into Garvin’s talk. You have the option of watching the presentation in six higher-resolution YouTube clips (below). Or you could download the high-res files from Goddard’s Scientific Visualization Studio site.

Garvin covers Mercury, Venus, the moon, asteroids, Earth (a wee bit), and then Mars (quite a bit). He covers the detailed history of what we’ve done and what we still want to do. Garvin scores big points with his enormous energy and enthusiasm, deep knowledge of the subject (he’s a planetary scientist), and a humorous touch.

Check it out if you want an update from the bleeding edge of NASA planetary science from a true insider. It’s watchable and packed with interesting science/tech tidbits.

If you have a fast Internet connection, set the video segments below to play back at 720p for the maximum High Def data blast.


















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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.

[Um.... Make that the TUESDAY video rewind picture show. We had a network outage yesterday, so sorry about that. We now return to our regularly scheduled programming. . . ]

Given the recent upturn in stormy solar activity, it seemed a good time to revisit the spectacular piece of visualization known as Sentinels of the Heliosphere. This video debuted in 2009 at SIGGRAPH, an international conference and exhibition on computer graphics and interactive techniques.



_____________________________________________________________________________________________________ OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.



“I don’t know — when I was growing up, there was no such thing as planets around other stars. If you were to talk about it at a scientific meeting, people would laugh at you….”

Oh, how times change. And so begins a new short documentary by Goddard video producer Ryan Fitzgibbons and videographer Jamal Smith. 20 Years of Hubble Science: Exoplanets highlights the Hubble Space Telescope’s contributions to the study of planets around other stars.

In the video, Goddard scientists Marc Kuchner, Aki Roberge, and Jennifer Wiseman discuss how Hubble’s coronagraph and resulting images have helped scientists find exoplanets, dusty disks around other stars, and infant solar systems. All three astronomers are members of our Exoplanets and Stellar Astrophysics Laboratory.

The science is at the leading edge and the graphics are awesome — especially the animated timeline showing all exoplanet discoveries to date. Go to the Scientific Visualization Studio website to download and view this film at the highest possible resolution. It’s worth the download time.

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.