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December 12, 2012 | 18
The asteroid Vesta does not qualify as a planet, not even a dwarf planet. But the giant asteroid has plenty to offer planetary scientists nonetheless.
Vesta appears to be a differentiated body, like Earth, with distinct layers of core, mantle and crust. It also features some pretty dramatic topography. This photomosaic of Vesta's south pole, from NASA's Dawn spacecraft, centers on one of the tallest mountains in the solar system. The central peak within the crater Rheasilvia rises 22 kilometers, comparable with Mars's Olympus Mons and much higher than any mountain on Earth.
The mosaic comprises roughly three dozen images acquired by the Dawn spacecraft’s framing camera in 2011 and recently made available to the public. Daniel Macháček assembled the mosaic, along with several others, for his blog My Favorite Universe. In an English-language translation blog post for the Planetary Society, Macháček explained one curious feature of the mosaic—the unnatural pattern of shadows, which owes to Vesta's rapid rotation. "The shadows change so fast that there is not a set of images covering all of Vesta with the same lighting and from the same relative position of Vesta and Dawn," Macháček wrote. "My most viable option was to use the frames with the best lighting and minimal number of shadows."
Dawn shoved off from orbit around Vesta in September and headed for an even bigger asteroid. The spacecraft should arrive at Ceres, a body so large that it has been officially recognized as a dwarf planet, in 2015.
—John Matson
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18 Comments
Add CommentSOLID objects never orbit gas bags; a bullet cannot orbit a balloon. We're not that stupid.
Reply | Report Abuse | Link to thisThe work of piecing all that photo-material together is quite a work of art in itself. I at first had tried to figure that one large, noticeable impact crater or, depending on light angle, mountain. To do so, I followed my judgement on lighting only to soon see several highlight/shadow angles... My first thought was, 'What the...' and my very soon follow up response was, 'oh this must be a number of pieces. Then, I read the article. Wow. Great job, good work, and execllent information !
Reply | Report Abuse | Link to thisI found the last sentence confusing. The Dawn spacecraft will arrive at Ceres in 2015. Ceres was declared a dwarf planet by the IAU in 2006, according to Wikipedia.
Reply | Report Abuse | Link to thisIf by "gas bag" you refer to the Gas Giant planets, only the first 1000 km of Jupiter's radius is actually a gas. In order below that are supercritical liquid, solid metallic, and solid rocky layers. These are all at much higher temperatures than could remain solid under Earth normal conditions, but are kept in these states by enormous pressure.
Reply | Report Abuse | Link to thisThe Earth's core is as hot as the Sun's surface, and would be in a plasma state but for the large pressure from the whole planet squeezing it.
If the gas bag you are referring to is the SUN, which indeed is a plasma (not gas) throughout it's volume, you need to update your astronomy past the 17th century. The Sun has 99.9% of the mass of the Solar System, and gravity does not depend on what the mass is made of, just how much, and how far away you are (see Isaac Newton's work).
The whole last paragraph is confusing, it calls Ceres an asteroid in the first sentence and dwarf planet in the second. The paragraph should read more like:
Reply | Report Abuse | Link to this"Dawn...headed for an even larger Main Belt object, the dwarf planet 1 Ceres. The spacecraft should arrive in 2015."
The region between Mars and Jupiter should now be referred to as the Main Belt or Inner Belt, and not the "Asteroid Belt", since by mass it contains 1/3 dwarf planet (Ceres) and 2/3 asteroids. Small objects exist throughout the rest of the Solar System, and the Kuiper Belt has more total mass than the Inner Belt, although fewer discovered objects by number at this point. I think in the long run people will recognize there are two belts of minor planets, inner and outer (Kuiper), plus the scattered objects not concentrated in the belt regions.
What I find interesting in the picture, assuming sunlight is coming from the right, is up to six dark shadows suggesting cones, like cinder cones.
Reply | Report Abuse | Link to thisIf you found the sentence confusing, it is because you have only rudimentary notions of grammar. The word "body" is clearly an appositive to "Ceres," and is itself modified by the subordinate noun phrase beginning with "that." There will be a test at the close of this session.
Reply | Report Abuse | Link to thisI know you guys believe you know everything there is to know about spheres in space. But NASA images are not genuine nor truth-telling. NASA's images of Vesta were skewed, stretched, undeveloped and lacked hues so that depth-of-field was not discernible. Re-rendered to scale and with hues added, new details emerge.
Reply | Report Abuse | Link to thishttp://www.scienfree.org/images/SATURN/VESTA3dside.png
http://www.scienfree.org/images/SATURN/vesta05.png
http://www.scienfree.org/images/SATURN/vesta04.png
http://www.scienfree.org/images/SATURN/vesta03.png
By the way, I'm a former Xerox digital imaging tech and corporate trainer; and I begin a re-rendering (which I consider as an art-form) by defining "up and down," seeking details that manifest a response to gravity of some sort. Then I use scaling to create a visual focus; next I relight all the pixels; and finally, I add proportional hues to create a sense of depth-of-field. And that's how I work on each image.
Reply | Report Abuse | Link to thisGuys, I don't know whether to laugh or cry. The FACT you BELIEVE IN NASA's photoshopped, altered, UNDEVELOPED images just make's me grieve! How gullible do you wanna be? It's pathetic!
Reply | Report Abuse | Link to thisGuys, I don't know whether to laugh or cry. The FACT you BELIEVE IN NASA's photoshopped, altered, UNDEVELOPED images just make's me grieve! How gullible do you wanna be? It's pathetic!
Reply | Report Abuse | Link to thisAs you explained, the asteroid is spinning too fast to enable you to get an image of all its features with the same angle of illumination. That in itself makes your achievement all the more remarkable, without all those ignoramuses belittling it.
Reply | Report Abuse | Link to thisKeep up the good work, even with reduced funding!
EmilyCragg, I visited your webPage, excellent, thank you
Reply | Report Abuse | Link to thisEmilyCragg,
Reply | Report Abuse | Link to thisThank you for the entertaining website. I especially liked the "underground military compound" found in Victoria crater. It is unfortunate, however, that many uneducated conspiracy theorists will no doubt mistake the obvious parody of Richard Hoagland and his ilk as something remotely approaching the truth.
The truth is, by treaty we are not allowed to know the truth. Never mind, astronomy nor planetary politics. We are not privileged to KNOW. :shrug:
Reply | Report Abuse | Link to thisMight there be some things that are hidden from the general public? Perhaps so. But the fantastical claims on your site are completely ludicrous and are not backed up by any real data other than "I was an image technician for Xerox and my interpretations are the correct ones." Really? A hidden military complex on Mars? Then there is this gem, http://www.youtube.com/watch?v=Rg0TSuAdkUk. I like how you use the word "allegedly" just in case the real creator of the video comes forward and says it was all for a good laugh and not real.
Reply | Report Abuse | Link to thisWhat is true today is hidden by Federalist Elites who protect Treaties with ETs from the 1930s [with Germany]. You know and I know, Life is ubiquitous in different DNA formats, but always familiar in appearance. My claims are not fantastical, they're simply stating that Life is everywhere, and the people who deny IT are craZy or mind-controlled by official dogma. This is not "science" in any stretch of the imagination; it's wishing that what is true did not exist.
Reply | Report Abuse | Link to thisUngolythe, I have 40,000 NASA digital images on my hard-drive--Magellan, Apollo, Clementine, Cassini, etc., and about 1-2% are correctable to the point you can see people walking around. The image processors work very hard to conceal that by rotating (skewing), scrunching, stretching, dulling, adding pretty colors, etc. They want us to be fascinated with Space, as if it were an empty canvas for Terran Humanity to write a history. But fortunately or unfortunately, there is already a history written Out There. And it exists for us to LEARN, not for us to erase or write over.
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