Starship Asterisk*

THX1138 wrote:I'm sad to say that this optics focal length thing is really confusing for this astronomy 101 guy, darn it.
Question regarding my 10 inch reflector, Am i doing something wrong in that each time i drop in a higher magnification eye piece whatever i'm looking at grows darker and darker. I have the correct collimator eye piece for it and i always check and or adjust the mirror before every use of the scope. Am i doing something wrong. :?

A new animated video of dwarf planet Ceres, based on images taken by NASA's Dawn spacecraft, provides a unique perspective of this heavily cratered, mysterious world.

The video is based on observations of Ceres that were taken from Dawn's first mapping orbit, at an altitude of 8,400 miles (13,600 kilometers), as well as the most recent navigational images taken from 3,200 miles (5,100 kilometers).

Data from 80 images are combined into the video. Analysis of overlapping images provided three-dimensional detail. The vertical dimension is exaggerated by a factor of two in the video.

[img3="Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA"]http://photojournal.jpl.nasa.gov/jpeg/PIA19568.jpg[/img3][hr][/hr]

New images of dwarf planet Ceres, taken by NASA's Dawn spacecraft, show the cratered surface of this mysterious world in sharper detail than ever before. These are among the first snapshots from Dawn's second mapping orbit, which is 2,700 miles (4,400 kilometers) above Ceres.

The region with the brightest spots is in a crater about 55 miles (90 kilometers) across. The spots consist of many individual bright points of differing sizes, with a central cluster. So far, scientists have found no obvious explanation for their observed locations or brightness levels.

"The bright spots in this configuration make Ceres unique from anything we've seen before in the solar system. The science team is working to understand their source. Reflection from ice is the leading candidate in my mind, but the team continues to consider alternate possibilities, such as salt. With closer views from the new orbit and multiple view angles, we soon will be better able to determine the nature of this enigmatic phenomenon," said Chris Russell, principal investigator for the Dawn mission based at the University of California, Los Angeles. ...

[img3="This color-coded map from NASA's Dawn mission shows the
highs and lows of topography on the surface of dwarf planet Ceres.
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA"]http://www.jpl.nasa.gov/spaceimages/ima ... 606_ip.jpg[/img3][hr][/hr]

Colorful new maps of Ceres, based on data from NASA's Dawn spacecraft, showcase a diverse topography, with height differences between crater bottoms and mountain peaks as great as 9 miles (15 kilometers).

Scientists continue to analyze the latest data from Dawn as the spacecraft makes its way to its third mapping orbit.

"The craters we find on Ceres, in terms of their depth and diameter, are very similar to what we see on Dione and Tethys, two icy satellites of Saturn that are about the same size and density as Ceres. The features are pretty consistent with an ice-rich crust," said Dawn science team member Paul Schenk, a geologist at the Lunar and Planetary Institute, Houston.

Some of these craters and other features now have official names, inspired by spirits and deities relating to agriculture from a variety of cultures. The International Astronomical Union recently approved a batch of names for features on Ceres. ...

bystander wrote:New Names and Insights at Ceres
NASA | JPL-Caltech | Dawn | 2015 July 28

Some of these craters and other features now have official names, inspired by spirits and deities relating to agriculture from a variety of cultures. The International Astronomical Union recently approved a batch of names for features on Ceres. ...

https://en.wikipedia.org/wiki/Vegetation_deity wrote:
<<A vegetation deity is a nature deity whose disappearance and reappearance, or life, death and rebirth, embodies the growth cycle of plants. A vegetation deity is often a fertility deity. The deity typically undergoes dismemberment (see sparagmos), scattering, and reintegration, as narrated in a myth or reenacted by a religious ritual. The cyclical pattern is given theological significance on themes such as immortality, resurrection, and reincarnation. Vegetation myths have structural resemblances to certain creation myths in which parts of a primordial being's body generate aspects of the cosmos, such as the Norse myth of Ymir. In J.G. Frazer's _The Golden Bough_ [this] figure is related to the "corn spirit," "corn" in this sense meaning grain in general. That triviality is giving the concept its tendency to turn into a meaningless generality.>>

• and often even extremely embarrassing.

bystander wrote:Bright Spots Shine in Newest Dawn Ceres Images
NASA | JPL-Caltech | Dawn | 2015 Jun 10

"The bright spots in this configuration make Ceres unique from anything we've seen before in the solar system. The science team is working to understand their source. Reflection from ice is the leading candidate in my mind, but the team continues to consider alternate possibilities, such as salt. With closer views from the new orbit and multiple view angles, we soon will be better able to determine the nature of this enigmatic phenomenon,"
said Chris Russell, principal investigator for the Dawn mission based at the University of California, Los Angeles. ...

[img3="Dawn spotted this tall, conical mountain on Ceres. The mountain, located in the southern hemisphere, stands 4 miles (6 kilometers) high. Its perimeter is sharply defined, with almost no accumulated debris at the base of the brightly streaked slope."]http://www.jpl.nasa.gov/spaceimages/ima ... 631_ip.jpg[/img3]

[img3="Dawn took this image that shows a mountain ridge, near lower left, that lies in the center of Urvara crater on Ceres. Urvara is an Indian and Iranian deity of plants and fields. The crater's diameter is 101 miles (163 kilometers)."]http://www.jpl.nasa.gov/spaceimages/ima ... 632_ip.jpg[/img3]

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[img3="Dawn took this image of Gaue crater, the large crater on the bottom, on Ceres. Gaue is a Germanic goddess to whom offerings are made in harvesting rye. The center of this crater is sunken in. Its diameter is 84 kilometers (52 miles)."]http://www.jpl.nasa.gov/spaceimages/ima ... 633_ip.jpg[/img3]

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The closest-yet views of Ceres, delivered by NASA's Dawn spacecraft, show the small world's features in unprecedented detail, including Ceres' tall, conical mountain; crater formation features and narrow, braided fractures.

"Dawn is performing flawlessly in this new orbit as it conducts its ambitious exploration. The spacecraft's view is now three times as sharp as in its previous mapping orbit, revealing exciting new details of this intriguing dwarf planet," said Marc Rayman, Dawn's chief engineer and mission director, based at NASA's Jet Propulsion Laboratory, Pasadena, California.

At its current orbital altitude of 915 miles (1,470 kilometers), Dawn takes 11 days to capture and return images of Ceres' whole surface. Each 11-day cycle consists of 14 orbits. Over the next two months, the spacecraft will map the entirety of Ceres six times.

The spacecraft is using its framing camera to extensively map the surface, enabling 3-D modeling. Every image from this orbit has a resolution of 450 feet (140 meters) per pixel, and covers less than 1 percent of the surface of Ceres.

At the same time, Dawn's visible and infrared mapping spectrometer is collecting data that will give scientists a better understanding of the minerals found on Ceres' surface. ...

Image Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

https://en.wikipedia.org/wiki/Ceres_%28dwarf_planet%29_in_fiction wrote:

[i][b][color=#0000FF]Dawn spotted this tall, conical mountain on Ceres. The mountain, located in the southern hemisphere, stands 4 miles high. Its perimeter is sharply defined, with almost no accumulated debris at the base of the brightly streaked slope.[/color][/b][/i]

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Ceres (dwarf planet) in fiction

In Garrett P. Serviss' Edison's Conquest of Mars (1898), the Martians from H.G. Wells' The War of the Worlds (1897) are engaged in a war with giant beings from Ceres.

Ceres is mentioned in some of the stories of Isaac Asimov, who usually situates an observatory on Ceres, as for example in the juvenile novel Lucky Starr and the Pirates of the Asteroids (1953) and the Wendell Urth mystery "The Dying Night" (1956).

In Alfred Bester's book The Stars My Destination (1956), the main character claims to be a wealthy lord from Ceres.

Ceres is a prison planet in the A. Bertram Chandler's novelette "Raiders of the Solar Frontier" (1950) published in Donald A. Wollheim's pulp magazine Out of This World Adventures

In The Dune Encyclopedia (1984), Ceres becomes the "Seat of the Empire" (i.e., capital) after Earth is hit by an asteroid.

In Larry Niven's Known Space stories (1964 onward), the asteroid belt has a government based on Ceres. It is also the site of the narrow but deciding victory against the Kzin Fourth Fleet during the First Man-Kzin War.

In Jerry Pournelle's Exiles to Glory (1974, republished 2007) Ceres is the site of an interplanetary mystery involving the theft of asteroid-mined super-heavy metals.

In Bob Shaw's book The Ceres Solution (1981), extraterrestrials attempt to use Ceres to destroy Earth's moon thereby removing the effect of "third-order forces" that have been stunting human development since the dawn of civilization.

In L. Neil Smith's novel The Venus Belt (1981), Ceres contains a large underground city and several small settlements and stations, connected by a network hi of inverted highways.* In Bruce Sterling's novel Schismatrix (1985), Ceres Datacom News is a quasi-national entity networking the communications of the cybernetically enhanced inhabitants of the asteroids.

In S. M. Stirling's Draka novel The Stone Dogs (1990), the Alliance for Democracy has a large base on Ceres.

In Marooned in Realtime (1986) by Vernor Vinge, one of the murder suspects is the holder of a PhD in Mayan archaeology from the Universidad Polytecnica de Ceres.

Ron-Astro Pharmacist wrote:
Dawn's plot is unfolding right before our eyes. Thanks for the fiction references Art and, as always, the astronomical updates from bystander. Glad you didn't forget one of my favorites… IA - my favorite among many great choices.

After all he originally coined a term describing such bodies. I wonder how much the IAU considered his terminology. Maybe it was somewhere in the "meso"?

https://en.wikipedia.org/wiki/Isaac_Asimov wrote:
<<Isaac Asimov (born Isaak Yudovich Ozimov; circa January 2, 1920 – April 6, 1992) was a prominent member of the Baker Street Irregulars, the leading Sherlock Holmes society, for whom he wrote an essay arguing that Professor Moriarty's work "The Dynamics of An Asteroid" involved the willful destruction of an ancient civilized planet.>>

https://en.wikipedia.org/wiki/Lucky_Starr_and_the_Pirates_of_the_Asteroids wrote:
<<Returning to Ceres, Lucky Starr learns that Captain Anton's ship is taking Hansen to a secret Sirian base on Ganymede, whence the Sirians plan to attack Earth while Earth's fleet is occupied fighting the pirates in the Asteroid Belt. Lucky Starr and the Pirates of the Asteroids introduces the Sirians as the main threat to Earth. Pirates of the Asteroids turns the standard revenge drama plot on its head. Instead of spending the novel tracking down the man who killed his parents, Starr spends much of his time in the man's company, fully aware of his identity but pretending ignorance in order to reach his larger goal of ending the pirate menace. Instead of a climactic showdown that ends in Hansen's violent death, Starr patiently explains to him that his plan to help the Sirians conquer Earth has been thwarted, and persuades him to talk the Sirians into leaving the Solar System.>>

neufer wrote:
<<Returning to Ceres, Lucky Starr learns that Captain Anton's ship is taking Hansen to a secret Sirian base on Ganymede, whence the Sirians plan to attack Earth while Earth's fleet is occupied fighting the pirates in the Asteroid Belt. Lucky Starr and the Pirates of the Asteroids introduces the Sirians as the main threat to Earth. Pirates of the Asteroids turns the standard revenge drama plot on its head. Instead of spending the novel tracking down the man who killed his parents, Starr spends much of his time in the man's company, fully aware of his identity but pretending ignorance in order to reach his larger goal of ending the pirate menace. Instead of a climactic showdown that ends in Hansen's violent death, Starr patiently explains to him that his plan to help the Sirians conquer Earth has been thwarted, and persuades him to talk the Sirians into leaving the Solar System.>>

[img3="This image, made using images taken by NASA's Dawn spacecraft, shows
Occator crater on Ceres, home to a collection of intriguing bright spots.
Credits: Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA"]http://www.nasa.gov/sites/default/files ... a19889.jpg[/img3][hr][/hr]

The brightest spots on the dwarf planet Ceres gleam with mystery in new views delivered by NASA's Dawn spacecraft. These closest-yet views of Occator crater, with a resolution of 450 feet (140 meters) per pixel, give scientists a deeper perspective on these very unusual features.

The new up-close view of Occator crater from Dawn's current vantage point reveals better-defined shapes of the brightest, central spot and features on the crater floor. Because these spots are so much brighter than the rest of Ceres' surface, the Dawn team combined two different images into a single composite view -- one properly exposed for the bright spots, and one for the surrounding surface.

Scientists also have produced animations that provide a virtual fly-around of the crater, including a colorful topographic map.

Dawn scientists note the rim of Occator crater is almost vertical in some places, where it rises steeply for 1 mile (nearly 2 kilometers).

Views from Dawn's current orbit, taken at an altitude of 915 miles (1,470 kilometers), have about three times better resolution than the images the spacecraft delivered from its previous orbit in June, and nearly 10 times better than in the spacecraft's first orbit at Ceres in April and May. ...

http://dawn.jpl.nasa.gov/
http://www.nasa.gov/dawn

BMAONE23 wrote:
Where there were two distinct White Spots, there is now a single bland patch with interesting linear features

Because these spots are so much brighter than the rest of Ceres' surface, the Dawn team combined two different images into a single composite view -- one properly exposed for the bright spots, and one for the surrounding surface.

[img3="This map-projected view of Ceres was created from images taken by NASA's Dawn spacecraft during its high-altitude mapping orbit, in August and September, 2015.
(Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)"]http://www.jpl.nasa.gov/spaceimages/ima ... 977_ip.jpg[/img3][hr][/hr]

Mysteries and insights about Ceres are being discussed this week at the European Planetary Science Conference in Nantes, France. NASA's Dawn spacecraft is providing scientists with tantalizing views and other data about the intriguing dwarf planet that they continue to analyze. ...

A new color-coded topographic map shows more than a dozen recently approved names for features on Ceres, all eponymous for agricultural spirits, deities and festivals from cultures around the world. These include Jaja, after the Abkhazian harvest goddess, and Ernutet, after the cobra-headed Egyptian harvest goddess. A 12-mile (20-kilometer) diameter mountain near Ceres' north pole is now called Ysolo Mons, for an Albanian festival that marks the first day of the eggplant harvest.

Another new Ceres map, in false color, enhances compositional differences present on the surface. The variations are more subtle than on Vesta, Dawn's previous port of call. Color-coded topographic images of Occator (oh-KAH-tor) crater, home of Ceres' brightest spots, and a puzzling, cone-shaped 6-mile-high (4-kilometer-high) mountain, are also available. Scientists are still trying to identify processes that could produce these and other unique Cerean phenomena. ...

[img3="Cosmic Flypaper: Experiments using a high velocity cannon suggest that when asteroids hit targets that are icy or made of porous silicate materials, much of the impact material stays in the crater. The findings have implications for the surface composition of the dwarf planet Ceres. (Image: NASA Ames Research Center)"]https://news.brown.edu/files/styles/hor ... Ceres1.jpg[/img3][hr][/hr]

Ceres, the largest object in the asteroid belt and closest dwarf planet to Earth, had been remarkable for its plain surface. New research suggests that most of the material that has struck Ceres in high-speed collisions has stuck — billions of years worth of meteorite material.

A new set of high-velocity impact experiments suggests that the dwarf planet Ceres may be something of a cosmic dartboard: Projectiles that slam into it tend to stick.

The experiments, performed using the Vertical Gun Range at NASA’s Ames Research Center, suggest that when asteroids and other impactors hit Ceres, much of the impact material remains on the surface instead of bouncing off into space. The findings suggest the surface of Ceres could consist largely of a mish-mash of meteoritic material collected over billions of years of bombardment. ...

Ceres is the largest object in the asteroid belt and the nearest dwarf planet to Earth. Until the recent arrival of the Dawn spacecraft, all that was known about Ceres came from telescopic observations. The observations showed Ceres to be mysteriously low in density, suggesting it is made either of very porous silicate material, or perhaps contains a large layer of water ice. Observations of its surface were remarkable as well — largely for being unremarkable. ...

And to understand impact processes, the researchers turned to NASA’s Vertical Gun Range, a cannon with a 14-foot barrel that can launch projectiles at up to 16,000 miles per hour. For this work, Daly and Schultz wanted to simulate impacts into low-density surfaces that mimic the two broad possibilities for the composition of Ceres’s surface: porous silicate or icy. ...

• Geophysical Research Letters (online 13 Oct 2015) DOI: 10.1002/2015GL065601