does anyone know of a science related article....?

Question

i need a article that is related to a science topic that i can use for my science class.
it can be anything...... like about planets or diseases or anything like that

anything that i can look up online would help too..... anything acience related...like planets or diseases

Answer 1

Go to ScienceDaily. There a whole bunch or articles there. I use it everytime I need one.

www.sciencedaily.com

Answer 2

1

Answer 3

One excellent place to begin is your local newspaper or if you wish you can go on-line to the Washington Post.com or New York times or other papers and use their archive search features using science as a keyword. This will give you everything that has been printed in the paper for whatever period of time you specify. In these articles you will find references to the most current research results, who the researchers are, where their results have been published, and so on. You can then retrieve the original publications through your library. I heartily recommend this approach over a reliance on doing a web search alone. All too often what we find on the web is not well documented, incorrect citations, and questionable conclusions. I would go to the web only to do the newspaper archive search.

In conducting a similar search the other day on a similar question I dialed up washingtonpost.com, went to the bottom of the page, and typed in "global climate change" in the search box. The search came back with 161 results in the past 60 days alone together with short abstracts on each article. You may click on any of these to retrieve the entire article. This is a quick and honest way to do your research and it will be easy to document, with dates, authors, article names, and newspaper. An excellent way to prepare for a class assignment.

Answer 4

do no longer recognize what point of school you're in, or what your hobbies are, yet right that's some starters....and that i'm quite previous form, so off to the library with you! some dynamite magazines that have exciting technology articles, which you will have the skill to apply: Smithsonian technology information medical American under pressure greater effective yet, grab your friendly community or college librarian (who knows plenty approximately a thank you to do study, and who would be happy to share information), and ask for some greater concepts. Librarians are the secret Masters of the Universe, when you consider that they administration tips. good success!

Answer 5

Go look at Discover magazine in the library.

Answer 6

Extinction Tied to Global Warming
Greenhouse Effect Cited in Mass Decline 250 Million Years Ago

By Guy Gugliotta
Washington Post Staff Writer
Friday, January 21, 2005; Page A03

Scientists call it "the Great Dying," a 250 million-year-old catastrophe that wiped out 90 percent of ocean species and 70 percent of land species in the biggest mass extinction in Earth's geologic history.

The cause of this cataclysm is a matter of great dispute among paleontologists, but research released yesterday offers new evidence that global warming caused by massive and prolonged volcanic activity may have been the chief culprit.

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Huge amounts of carbon dioxide were released into the air from open volcanic fissures known to geologists as the "Siberian Traps," researchers said, triggering a greenhouse effect that warmed the earth and depleted oxygen from the atmosphere, causing environmental deterioration and finally collapse.

A second set of findings suggested that the warming also crippled the oceans' ability to refresh their oxygen supply, causing the seas to go sterile, destroying marine life and allowing anaerobic bacteria (which do not require oxygen) to release poisonous hydrogen sulfide "swamp" gas into the air.

The two reports, prepared independently, both cast doubt on another theory -- that the Great Dying was caused by the impact of an asteroid or comet such as the one that triggered the extinction of the dinosaurs 65 million years ago. Both studies were published yesterday by Science Express, the online version of the journal Science.

"This is not a world that is happy and then goes 'Bang!' " said University of Washington paleontologist Peter D. Ward, leader of one of the two new studies. "This is a world that's in trouble for a long time, and then it gets in even worse trouble."

Ward led a team of scientists in a seven-year project to chronicle 126 fossil skulls in a 1,000-foot-thick deposit of sedimentary rock in southeastern South Africa's Karoo Basin. He said in a telephone interview that the samples included reptiles and some amphibians, ranging from dog-size animals to predatory gorgonopsians, which he described as "a hideous cross between a lion and a particularly nasty lizard."

Ward said the team's excavations showed a steady decline in the number of species over 10 million years, followed by a sudden plunge 250 million years ago at the boundary between the Permian and Triassic periods of geologic time. The interval corresponds to a period of prolonged volcanic activity over one-third of modern-day Siberia.

Temperatures climbed globally as carbon dioxide poured into the atmosphere and oxygen levels fell, forcing gasping animals to gather at sea level, he said. "And the plants are not dealing well with the heat" either, he added. "Eventually the imbalance reaches a critical point, and everything dies."

The warming also meant that polar oceans were not cooled as much as they are today, and the convection cycle that circulates cold, oxygen- and nutrient-rich water between the poles and the tropics was slowed and even stopped, according to the second paper by a team of researchers led by Kliti Grice of the Curtin University of Technology in Perth, Australia.

"This has devastating effects on the marine organisms that rely on oxygen and nutrients to survive," the team said in an e-mail. "In the worst-case . . . a major part of the water column above the sea floor is devoid of oxygen."

Analyzing sulfur and carbon isotopes from core samples taken from the ocean bed off the coast of northwestern Australia, the team detected molecular traces from green sulfur bacteria, known as Chlorobiaceae, at the time of the Great Dying.

"The beauty of these [bacteria] is that they require sunlight and an anoxic [oxygen-free] environment," said team member Steven Turgeon, an Oak Ridge National Laboratory geochemist. "Because they live so close to the surface, we're pretty sure that what's beneath is anoxic."

This combination of factors, which has also been detected in waters off southern China, indicates that large swatches of ocean below a depth of 300 feet -- the deepest that significant light can penetrate -- became sterile, and that the entire ocean may have been oxygen-free.

Just as important, the bacteria derive energy from sulfate compounds in seawater and vent poisonous hydrogen sulfide gas into the air, Turgeon noted in a telephone interview.

The Grice team did not address the cause of the lethal warming, but Ward said his team found no evidence of the residue that would have fallen after a comet or asteroid impact threw tons of dust into the air to trigger a sudden and catastrophic greenhouse effect.

Still, University of Rochester earth scientist Robert Poreda, a proponent of the impact theory, noted that the "absence of evidence" at Karoo Basin "does not constitute evidence of absence."

"We propose there was preexisting volcanism" that became much worse because of the seismic energy released by the asteroid or comet impact, he said. "Some people have thought it feasible, while others have been adamantly opposed."
Sedna

The coldest most distant place known in the solar system; possibly the first object in the long-hypothesized Oort cloud

Artist's conception of the cold distant Sedna. The sun is a tiny point of light 8 billion miles away from the red planetoid. A hypothesized tiny moon appears nearby.

Artist's conception of the Inuit goddess Sedna, who rules over the seas (from the collection of M.E Brown).

The view from Sedna with everything identified

See the nice cover article in Discover Magazine about Sedna and the rest of the outer solar system

Does Sedna have a moon?

Is Sedna a planet? (is Pluto a planet? what exactly makes something a planet?)
Read the scientific paper describing this discovery
On 15 March 2004, astronomers from Caltech, Gemini Observatory, and Yale University announced the discovery of the coldest, most distant object known to orbit the sun. The object was found at a distance 90 times greater than that from the sun to the earth -- about 3 times further than Pluto, the most distant known planet.

The discovery was made on the Samuel Oschin Telescope at the Palomar Observatory east of San Diego on 14 November 2003 by the team of Mike Brown (Caltech), Chad Trujillo (Gemini Observatory) and David Rabinowitz (Yale).

Because of its frigid temperatures, the team has named the object Sedna, after the Inuit goddess of the sea from whom all sea creatures were created.

How far away is Sedna?
Sedna is the most distant solar system object ever discovered. It is twice as far from the sun as any other solar system object and three times farther than Pluto or Neptune. Standing on the surface of Sedna, you could block the entire sun with the head of a pin held at arm's length.

Even more interestingly, the orbit of Sedna is extreme elliptical, in contrast to all of the much closer planets, and it takes 10,500 years to circle the sun.

Here is an image of the orbit and position compared to all the known solar system objects (click for bigger version)


The sun is in the middle of the swarm of solar system objects. You can see that Sedna is at 90 AU (1 AU is an Astronomical Unit, the distance between the earth and the Sun, about 150 million kilometers, or 93 million miles).

Don't miss the fabulous video, put together by Robert Hurt at the Spitzer Science Center, showing a zoom out from the earth to Sedna to the Oort cloud (Robert is also responsible for the artist's rendition of Sedna at the top).

What is the Oort cloud and what is its relationship to Sedna?
The Oort cloud is a hypothetical shell of icy proto-comets in very loose orbits around the sun that extends to a distance of almost halfway to the nearest star. Occasionaly, passing stars cause a slight change in the orbit of one of these proto-comets which causes them to come steaking in to the inner solar system where we see them as comets. A nice explanation can be found here. Though the Oort cloud has never been seen directly, the comets that we do see are very strong evidence of its existence. As can be seen in the graphic above, though, the Oort cloud is expected to be much much further out than the orbit of Sedna. So why do we think Sedna is a member of the Oort cloud? We believe that the existence of Sedna is evidence that the Oort cloud actually extends much further in towards the sun than previously thought. This "inner Oort cloud" was formed in the same manner as the previously known "outer Oort cloud." Early in the history of the solar system many many small icy bodies were orbiting the sun and getting sling-shot out by close encounters with planets. As they were travelling further and further from the sun, the orbits of these bodies were affected by distant stars, causing them to slow down and stay attached to the sun. Sedna probably suffered a similar fate, except the stars which affected it must have been much much closer than previously expected. We believe that this is evidence that the sun formed in a tight-knit group along with many other stars.
How big is Sedna?
In our discovery images, we see only a point of light. We can't directly measure the size of Sedna from this point. The light that we see has travelled from the sun, been reflected off the surface of Sedna, and come back to us where we can see it in the images like the discovery images below. So a small icy object and a large coal-covered object, for example, would both look about the same brightness in the discovery images, because both objects could reflect about the same amount of sunlight.

We can measure Sedna's size using a thermal telescope, which measures the heat coming from the surface. We know how far away Sedna is, so we know that the surface temperature is about 400 degrees below zero Farenheit. A large object of that temperature will give off much more heat than a small object of that temperature (just light a match and a bonfire are the same temperature, but a bonfire keeps you much warmer at night because it is so much bigger). In collaboration with Frank Bertoldi at the MPIfR Bonn, we used the 30 meter diameter IRAM telscope, and in collaboration with John Stansberry at the University of Arizona and Bill Reach at the Spitzer Science Certer, we used the Spitzer Space Telescope. Sedna was too small to be detected in either. This tells us that Sedna is at most about 1800 km in diameter: about halfway in size between Pluto and the largest known Kuiper belt object Quaoar. Even though all we know for certain is that Sedna is smaller than 1800 km, we have evidence which suggests that the size might be pretty close to this number. We are virtually certain that the size is larger than the 1250 km size of Quaoar, though this object has shown many unexpected characteristics, so we can't completely rule out a smaller size.



Is Sedna a planet?
NO, at least not by our definition. Astronomers have been unable to agree on a precise definition of "planet", but we have a suggestion for a definition below which is both historically and scientifically motivated. By our definition, Sedna is not a planet. Nor is Pluto. But the other 8 are.

What is the definition of a planet?
Astoundingly, no precise scientific definition of the word "planet" currently exists. It is rare for scientists to have to define a word that is already in common usage and that everybody from school children on up already understand. How does one then go about constructing a scientific definition of such a word after the fact?

In such cases, we believe that it is important to be both true to the historical and popular perception of the meaning of the word while being scientifically descriptive, accurate, and meaningful. We will use these points -- historically valid and scientifically meaningful -- as the criteria on which to judge potential definitions of the word "planet." We have identified 4 major ideas for the definition of the word "planet" (though the most common have never been written down to our knowledge):

Purely historical. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto are planets. Nothing else in the solar system is a planet. This definition is definitely historically valid, but fails miserably under scientific meaning. What if a new object larger than Pluto is found? What is it? Why is Pluto a planet but an object 3/4 its size, like Sedna, is not? This definition, completely lacking in scientific motivation, makes the word "planet" meaningless as a scientific description.
Historical plus. Mercury through Pluto are planets, as is any newly discovered object larger than Pluto. This definition is, we believe, the one in most common colloquial use throughout the world, even if people don't realize that this is the definition they are using. Indeed, if Sedna had been larger than Pluto, most would have hailed it as a 10th planet. This definition -- like the previous -- is historically consistent, but -- like the previous -- still fails the scientific test. Why is Pluto the cutoff size? Is there really a big enough difference in size between Pluto and Sedna and Quaoar that one should be called a planet while the others are not? The scientific answer remains a resounding no.
Gravitational rounding. Any object which is round due to its own gravitational pull and which directly orbits the sun is called a planet. This definition is very different! It is strictly scientific, yet historically valid, as all objects that we call planets by the historical definitions are indeed round due to their own gravitational pull. More importantly (and by a complete coincidence) the dividing line between objects which are round and those which are not round is just a few times smaller than the size of Pluto. So why not take advantage of this coincidence and simply define planets to be objects which are round? To do so means that we must admit several other bodies to the class of "planet." Sedna, Quaoar, the asteroid Ceres, and perhaps a dozen Kuiper belt objects are also likely to be round and thus, by this definition, planets. But these additions are perhaps a small price to pay for a definition which rests on solid scientific principles.
Unfortunately, this definition completely fails the historical sanity check. Historically, where does the criterion to be round come from, except for the near coincidence between the historical definition of planet and the transition size from round to not round? At no time in previous history has any discussion of whether or not an object is round been part of the discussion of whether or not it should be called a planet. Ceres was initially considered to be a planet, but not because it is round (which was unknown at the time), but because it was the only object known to exist between Mars and Jupiter. When other asteroids of similar sizes were found at nearly the same location it was decided to call them all members of the asteroid belt, rather than planets.

Roundness is an important physical property, and gravity is the dominant force in the solar system, so perhaps it is important to have a special word which describes the class of objects in the solar system which are round. But simply because all historical planets are round does not at all mean that it is good science to define all round objects to be planets. A much better idea is to use a different word to descibe these objects. Spheroids? Gravispheres? Actually, we prefer the word "planetoid" as a new word to descibe round objects orbiting the sun. All planets are planetoids. Not all planetoids are planets.

Population classification. This definition requires a little more explanation and a little more understanding of the solar system, but, in the end, leads to the most satisfactory definition of "planet". Just like the solar system very naturally divides itself between round objects and non-round objects, it also very naturally divides itself between solitary individuals and members of large populations. The best known example of a large population is the asteroid belt. We call it a population because one region of space contains objects with a continuous range of sizes from one moderately large object (Ceres) to a handful of slightly smaller objects (Vesta, Pallas, Hermione) to a huge number of extremely small objects (rocks, dust particles). The solitary individuals are much different. In their region of space there is only them (Earth, say) and then a collection of much much smaller objects (the near-earth asteroids), with no continuous population in between. A single example helps to dramatize the difference between a continuous population and a solitary individual. Ceres, the largest asteroid, has a diameter of 900 km. The next largest asteroid, Pallas, has a diameter of 520 km. After that is Vesta at 500 km, and Hygiea at 430 km, and the list continues on down. The jump in size between asteroids is never more than a factor of two. In contrast, the earth has a diameter of about 12,000 km, while the largest other object in the earth's vicinity, the asteroid Ganymed, has a diameter of about 41 km, a factor of 300!
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune all count as solitary individuals by this definition. Pluto and Quaoar do not. Pluto is clearly a member of the Kuiper belt population, as can be seen from the fact that there are objects in the same vicinity slightly smaller than Pluto (Quaoar, 2004 DW, Varuna), and then even a larger number slightly smaller than that, and then on down.

What about Sedna? Sedna is currently the only object known in its orbital vicinity, but we strongly suspect that there will be many others found out there with time. We thus feel it is more reasonable to classify Sedna as a member of a large population (the inner Oort cloud of objects) rather than a solitary object. This classification saves us from having to go back and reclassify Sedna in a decade when we find more objects!

Since there is a clear scientific distinction between solitary individuals and members of large populations it is instructive to come up with words to describe these objects. The large populations can each be described by the particular population (asteroid belt, Kuiper belt, inner Oort cloud, Oort cloud). What about the solitary individuals? Isn't the best word to describe them "planet"?

Let's examine this definition in more details. First, it is certainly scientifically motivated and well-founded. But so was the "gravisphere" definition above. Is there any historical basis for saying that a planet is a solitary individual that is not a member of a large population? Yes! As mentioned earlier, historically Ceres and the first few asteroids were initially classified as planets. Only when it became known that there were many many asteroids in similar orbits was it decided that they should no longer be classified as planets. Historically, there is a clear distinction between planets and populations. Any definition which fails to make this distrinction is in strong trouble on historical grounds. This simple look at history shows that Pluto is completely analogous to Ceres. Pluto was initially thought to be a solitary individual. Over time we found more objects in the vicinity and realized instead that it is a member of a large population. Historically, then, Pluto, too, should no longer be considered a planet.

We are thus left with a final concept of the word planet. Every object in the solar system quite naturally can be classified as either a solitary individual or a member of a large population. The individuals are planets. The populations are not. This definition fits the historical desire to distinguish between asteroids and planets, and this definition fits all of the requirements of scientific motivation.

Even this definition is not perfect. People will always be able to imagine (and perhaps even find) pathological scenarios in which the above classification scheme fails. In contrast, the first three definitions are much more rigorous and will never need refining. We don't find this aspect of the first definitions an advantage, however. As we learn more about our solar system our language -- both popular and scientific -- should change to fit our knowledge. We think that our proposed classification scheme will suffice for everything that is found in our solar system, but we would like nothing better than to find some object which defies everything that we currently think we know and forces us to completely rethink fundamental questions like "what is a planet."

How well is the orbit known?
We know the orbit fairly well. After finding Sedna in November 2003, we were able to trace it back in archival data to 2001. With this nearly 3 year arc, we know that the perihelion (closest approach distance) is most likely to be within about 7 AU of our 76 AU perihelion estimate. With a perihelion of 76 AU, Sedna has a 60% farther closest approach than any other solar system object. We expect that the orbit will be improved in coming weeks as people search though archival data.

Is Sedna a Kuiper belt object?
NO. Sedna never enters the region of the Kuiper belt. The Kuiper belt is an icy asteroid belt just beyond Neptune. Extremely strong evidence shows that it has a rather sharp edge at 50 AU. Sedna never comes close than 76 AU. Calling Sedna an inner Oort cloud object makes much more sense.

There are some KBOs that go very far from the sun like Sedna does, but they all have closest approach at about 35-45 AU. Sedna is special because it doesn't come any closer than 75 AU to the sun. We believe that this is because of the effects of passing stars, as described above.

A second speculative explanation for Sedna's orbit is that a larger body, perhaps Mars-sized or larger could exist at around 70 AU in a circular orbit and could have caused Sedna to get thrown into its strange orbit. If such a planet existed, we would likely have already found it in our survey, though there are still a few places left to hide.

How was Sedna found?
We have been conducting an ongoing survey of the outer solar system using the Palomar QUEST camera and the Samuel Oschin Telescope at Palomar Observatory in Southern California. This survey has been operating since the fall of 2001, with the switch to the QUEST camera happening in the summer of 2003. To date we have found around 40 bright Kuiper belt objects.
To find objects, we take three pictures of a small region of the night sky over three hours and look for something that moves. The many billions of stars and galaxies visible in the sky appear stationary, while satellites, planets, asteroids, and comets appear to move. Objects in the inner Oort cloud are extremely distant and so move extremely slowly.

These are two slightly differently processed views of the same 3 discovery images. The total area of sky shown in the bottom image is equivalent in size to the head of a pin held at arm's length. Incidentally, that is how big the Sun would appear from Sedna.





It is moving quite slowly and is faint, much slower and fainter than the recently discovered 2004 DW, which we also found.

Vast areas of the sky have to be searched before something this unusual is found. Our search for new objects will continue for the next few years.

How bright is Sedna; can I see it?
Sedna is about 20.5 magnitudes in R, considerably fainter than 2004 DW and Quaoar. It is beyond the reach of almost all amateurs astronomers (though, interestingly, the first confirmation of the existence of Sedna was made at Tenagra Observatory, an extremely high-end amateur telescope run by Michael Schwartz in southern Arizona).

In March 2004, the location of Sedna is easily found in the evening sky to the southwest just after sunset. It is almost directly below Mars, and forms a triangle with the very bright Venus. The following sky chart was accurate for mid-March 2004 and is only left in place for an historical reference.



Where is Sedna (the detailed version)?
For orbital elements suitable for your telescope, planetarium, or sky software, please see the Minor Planet Center page
What is Sedna made of?
We don't know. Because it's surface is relatively bright, from the thermal observations (see above), we might expect it to have water ice or methane ice like Charon and Pluto have. But observations from the Gemini Telescope and (in collaboration with Chris Koresko at JPL) the Keck telescope suggest that this is not true. From observations at the 1.3-m SMARTS telescope in Chile, we do know that Sedna is one of the most red objects in the solar system -- almost as red as Mars. Why? We're currently baffled.

Do we see a moon around Sedna?


When we first announced the discovery of Sedna, we noted that circumstantial evidence suggested that there is a moon around Sedna. Soon after, we acquired the images below with the Hubble Space Telescope . Much to our suprise no moon is visible!





Why did we think we would see a moon?

The evidence for the existence of a moon is circumstantial, but nonetheless compelling. The story is a little complicated, though, and it goes like this:

We have found that Sedna systematically gets a little brighter and a little fainter every 20 days or so (more complete information can be found here ). We think this is because there are bright and dark spots on the surface of Sedna and Sedna is rotating once every 20 days or so.

Most planets and asteroids rotate much more quickly. The earth rotates in 24 hours, Jupiter and Saturn rotate in about 10 hours, many asteroids rotate in just a handful of hours. Why is Sedna so different?

The answer perhaps can be found by thinking about Pluto. Pluto, too, has an unusually slow rotation: about 6 days. For many years this slow rotation was a mystery until it was realized that Pluto has a large moon, Charon, which revolves around Pluto once every six days. We now understand that Pluto once rotated more quickly, but Charon's tug on Pluto has, over time, slowed the rotation of Pluto until now Pluto finally rotates as slowly as Charon revolves around it.

The same process could explain why Sedna rotates unusually slowly. If Sedna has a large moon which revolves around it with a 20 day or so orbital period that moon would have slowed Sedna's initially faster rotation and given the unusually slow rotation seen today.

(As an interesting aside, this also happens on the earth! The moon is gradually slowing the earth's rotation over time. Over a typical person's lifetime, the earth day gets longer by about one one-thousandth of a second.)

Why is no moon visible?

We can think of 4 possibilities for why we do not see a moon around Sedna.

(1) Perhaps we got extremely unlucky and the moon is hiding directly behind Sedna. This possibility is unlikely (about 1 in 100 chance), but can't be ruled out completely.
(2) Perhaps the moon is fainter than expected. We think that the moon has to be quite large to explain the very slow rotation of Sedna, so we think that it should be bright. But it is possible that it is large but has a very dark surface and so is difficult to see. We believe that many objects (other than Sedna!) in the outer reaches of the solar system should be quite dark, so perhaps this suggestion is not unreasonable.
(3) Perhaps the moon is gone! It is possible that there once was a moon which slowed the rotation of Sedna but now the moon is gone. Moons can get destroyed by impacts with other large objects in space or they can be stripped away by close encounters with other planetoids. While we can't rule out this possibility, we do not think it is very likely.
(4) Perhaps our circumstantial evidence is misleading us. There are 2 ways that we can think of for this to have happened:
Perhaps the brightening and dimming that we think we see are not real. Measurements in science are never perfect, and perhaps some of these imperfections have, by bad luck, led us to believe that we are measuring Sedna's rotation when we are really not. From our understanding of the measurements, we can estimate that there is about a 1 in 20 chance of this type of bad luck. We thus think it is unlikely, but, again, we can't rule it out.
Perhaps the measurement is real, but we are being fooled. Imagine that you look at a clock once every twenty-five hours. How fast would you think the hands were turning? The first day the clock would say noon. The second day 1pm. The third day 2pm. You might think the clock only moved 1 hour per twenty-five hours. Perhaps the same thing is happening with Sedna: Our measurements were made approximately every 24 hours, so if Sedna rotates every 25 hours, then every time we look it appears to have only rotated a little, and we think it takes 24 days to make a full rotation. This possibility cannot be ruled out with the current data, though it would require the unusual coincidence that Sedna's rotation period would have to be unusually close to the earth's rotation period!
How will we learn more about the possibility of a moon?
Understanding which of the 2 above possibilities is correct will be possible from additional observations of Sedna. The two types of observations that we would most like to see are:

A careful look at the rotation of Sedna next year. Right now Sedna is too close to the sun to carefully observe, but next fall it will again be well-placed for astronomical study. At that time we hope to make a concerted effort too see if the rotation period is close to 24 hours instead of 20 or so days. We will do that by watching Sedna for a full night to see if it varies. If it is really rotating once every 20 days or so, we will see no change in a night. If it is rotating more quickly we should see the change.
An optimized set of pictures from the Hubble Space Telescope. The pictures from HST were specifically designed to make it most possible to measure the size of Sedna. Unfortunately, that doesn't give us the best view of a moon. We would like to try a very short HST observation optimized for a moon to either detect the moon or put the most stringent limits possible on how faint it must be.
Sedna, 2004 DW, Quaoar, 2002 AW197, why are all these new, big objects being discovered NOW?
Technology is the reason. Clyde Tombaugh discovered Pluto in 1930 using photographic plates, which let you look at a very wide piece of the sky, but they are not nearly as sensitive as the CCD's that we use now. (A CCD is what you will find inside most digital cameras.) The new, large objects listed above tend to be just faint enough that they would be out of range of all the older surveys for moving objects done after Tombaugh's. Today, CCD's are getting large enough and computers are getting fast enough that it is significantly easier to find these types of planetoids than it was even 5 years ago. We use a 172 Megapixel camera mounted on a robotic telescope to find these things. Even about 5 years ago, such cameras were not available, and the computing power to analyze these cameras was not quite there either.

Are there more inner Oort cloud objects like Sedna that we haven't seen?
It is very likely that there are more inner Oort cloud objects like Sedna. We have looked at only 15% of the sky before finding Sedna. As we continue to look at the sky, we may find a few more objects like Sedna. But this is only the beginning. Kepler's law states that an object on a very elliptical orbit like Sedna spends most of its time farthest from the Sun. Thus, for every Sedna we find near closest approach, there should be many more very far from the Sun that we can't see because they are so far away and faint. Also, Sedna is rather large, about 1/2 to 3/4 the size of Pluto. Most solar system populations like the Kuiper belt objects and the asteroids actually have many more smaller objects than large objects. So, for every Sedna we find that is large, there should be many more that are small that we missed because they were faint. Although it is very difficult to make predictions from one object, it seems very likely that the inner Oort cloud will have thousands of times more objects than just Sedna. It is likely that there is more mass in the inner Oort cloud than in the Kuiper belt and the asteroid belt combined.

Why is it called Sedna?
2003 VB12 was the official temporary designation of the International Astronomical Union (IAU) Minor Planet Center, based on the year (2003) and date (14 Nov = the 22nd 2-week period of the year thus V=the 22nd letter of the alphabet. after that it is sequential based on the discovery announcement) of discovery. Once the orbit of 2003 VB12 is known well enough (probably 1 year), we will reccomend to the IAU Committee on Small Body Nomenclature -- which is responsible for solar system names -- that it be permanently called Sedna (this has now happened, see above) . Our newly discovered object is the coldest most distant place known in the solar system, so we feel it is appropriate to name it in honor of Sedna, the Inuit goddess of the sea, who is thought to live at the bottom of the frigid arctic ocean. We will furthermore suggest to the IAU that newly discoverd objects in this inner Oort cloud all be named after entities in arctic mythologies.

You can find out more about the legend of Sedna from many websites and books, including the ones listed here