A stunning article, DW! I fancy science will to advance a lot, creating time and space patterns that are unfathomable to us at present. In US sci-fi films the scientifical battles interrupt an every day course but doesn´t change it. The heroes come back and find families and friends as they have left them.
But imagine a situation where you pass a weekend on a nearby star and come back finding everything has changed and your kids have become old people?
"I seemed to have sensed also from an early age that some of my experiences as a reader would change me more as a person than would many an event in the world where I sat and read. "
Gerald Murnane, Tamarisk Row
that would be truly horrific!
The SOCIETY for POPULAR ASTRONOMY
Electronic News Bulletin No. 445 2017 May 21
THIRD-LARGEST DWARF PLANET HAS MOON
NASA/Goddard Space Flight Center
The combined power of three space observatories, including the Hubble Space Telescope, has helped astronomers discover a moon orbiting the third-largest dwarf planet, catalogued as 2007 OR10.The pair resides in the frigid outskirts of the Solar System called the Kuiper Belt, a realm of icy debris left over from the system's formation 4.6 billion years ago. With this discovery,most of the known dwarf planets in the Kuiper Belt larger than 600 miles across have companions. Those bodies provide insight into how moons formed in the young Solar System. The discovery of satellites around all of the known large dwarf planets (except for Sedna) means that, when those bodies formed, a very long time ago, collisions must have been more frequent, and that is a constraint on the formation models. If there were frequent collisions, then it was quite easy to form satellites. The objects most likely slammed into one another more often because they inhabited a crowded region. But the speed of the colliding objects could not have been too fast or too slow, according to the astronomers. If the impact velocity were too great, the smash-up would have created lots of debris that could have escaped from the system; if too slow, the collision would have produced only an impact crater.
The team discovered the moon in archival images of 2007 OR10 taken by Hubble's Wide-Field Camera 3. Observations taken of the dwarf planet by the Kepler space telescope first tipped off the astronomers to the possibility of a moon circling it. Keple rrevealed that 2007 OR10 has a slow rotation period of 45 hours.Typical rotation periods for Kuiper-Belt Objects are under 24 hours. The team looked in the Hubble archive because the slower rotation period could have been caused by the gravitational effect of a moon. The initial investigator missed the moon in the Hubble images because it is very faint. The astronomers observed the moon in two separate Hubble observations spaced ayear apart. The images show that the moon is gravitationally bound to 2007 OR10 because it moves with the dwarf planet, as seen against a background of stars. However, the two observations did not provide enough information for the astronomers to determine an orbit. They calculated the diameters of both objects on the basis of observations in far-infrared light by the Herschel Space Observatory, which measured their thermal emission. The dwarf planet is about 950 miles across, and its moon is estimated to be 150--250 miles in diameter. 2007 OR10,like Pluto, follows an eccentric orbit, and is currently three times farther from the Sun than Pluto is. 2007 OR10 is a member of the exclusive club of 'dwarf planets', of which there are nine. Of those bodies, only Pluto and Eris are larger.
A FAR-FLUNG MEMBER OF THE SOLAR SYSTEM
National Radio Astronomy Observatory
Using the Atacama Large Millimeter/submillimeter Array (ALMA),astronomers have obtained extraordinary details about a recently discovered far-flung member of the Solar System, the planetary body 2014 UZ224, informally known as DeeDee. At about three times the current distance of Pluto from the Sun, DeeDee is the second-most-distant-known trans-Neptunian object (TNO) with a confirmed orbit, surpassed only by the dwarf planet Eris.Astronomers estimate that there are tens of thousands of such icy bodies in the outer Solar System beyond the orbit of Neptune.The new ALMA data reveal, for the first time, that DeeDee is roughly 635 kilometres across, or about two-thirds the diameter of Ceres, the largest member of the asteroid belt. At that size, DeeDee should have enough mass to be spherical, the criterion necessary for astronomers to consider it to be a dwarf planet,though it has yet to receive that official designation.Currently, DeeDee is about 92 astronomical units (AU) from the Sun. It takes DeeDee more than 1,100 years to complete one orbit; light from DeeDee takes nearly 13 hours to reach the Earth.
The object was discovered with the 4-metre Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile as part of ongoing observations for the 'Dark Energy Survey', that seeks to understand the accelerating expansion of the Universe. The Dark Energy Survey produces vast numbers of astronomical images, which give astronomers the opportunity to search also for distant Solar-System objects. The initial search, which includes nearly 15,000 images, identified more than a thousand million candidate objects. The vast majority of them turned out to be background stars and even-more-distant galaxies. A small fraction, however,were observed to move slowly across the sky over successive observations, the telltale sign of a TNO.
One such object was identified on 12 separate images. The astronomers informally dubbed it DeeDee, which is short forDistant Dwarf. The optical data from the Blanco telescope enabled the astronomers to measure DeeDee's distance and orbital properties, but they were unable to determine its size or other physical characteristics. It was possible that DeeDee was a relatively small member of the Solar System, yet reflective enough to be detected. Alternatively, it could be uncommonlylarge and dark, reflecting only a tiny portion of the feeble sunlight that reaches it; both scenarios would produce identical optical data. Since ALMA observes the cold, dark Universe, it is able to detect the heat -- in the form of millimetre-wavelength radiation -- emitted naturally by cold objects in space. The heat signature from a distant Solar-System object would be directly proportional to its size. By comparing the ALMA observations to the earlier optical data, the astronomers had the information necessary to calculate the object's size. Objects like DeeDee are cosmic leftovers from the formation of the Solar System. Their orbits and physical properties reveal important details about the formation of planets, including the Earth.This discovery shows that it is possible to detect very distant,slowly moving objects in the Solar System. The researchers note that the same technique might be used to detect the hypothesized'Planet Nine' that may reside far beyond DeeDee and Eris.
Interesting that cold objects emit heat that can be detected by ALMA. I didn't know that was detectable. I can see how reflected light can lead one to mistakes about the size of the object because of the different reflective properties of the object.
My blog: https://frankhubeny.blog/
Its quite a minor point, but I am wondering at the criteria for chosing names for their discoveries. They used to be better when there were fewer clestial bodies found and they stuck to the names of Greek gods. Nowadays there is a quite anticlimatic lettering and numbering of the new finds going on.
DeeDee is cute.
Last edited by Danik 2016; 05-21-2017 at 11:45 AM.
"I seemed to have sensed also from an early age that some of my experiences as a reader would change me more as a person than would many an event in the world where I sat and read. "
Gerald Murnane, Tamarisk Row
Yes the universe is unbelievably huge, and I see no way of going back to the old naming system of Greek gods.Originally Posted by Danik 2016
I found some links on the subject of naming celestial objects:
https://en.wikipedia.org/wiki/Astron...ng_conventions
"Celestial nomenclature has long been a controversial topic. At its inaugural meeting in 1922 in Rome, the IAU standardized the constellation names and abbreviations. More recently IAU Committees or Working Groups have certified the names of astronomical objects and features. In the following links you can find further information on how different objects and features are named."
https://www.iau.org/public/themes/naming/
Last edited by Danik 2016; 05-22-2017 at 07:44 AM.
"I seemed to have sensed also from an early age that some of my experiences as a reader would change me more as a person than would many an event in the world where I sat and read. "
Gerald Murnane, Tamarisk Row
That was enterprising of you Danik. It is clear that the whole business of nomenclature in astronomy is very problematic. We have ended up with an alpha-numeric soup that astronomers have created, for lack of an alternative terminology. Perhaps it is inevitable give how fast our knowledge of space as grown in recent years.
This item is interesting.
https://www.universetoday.com/135672...vintage-space/
It is interesting that in the 1940's people thought there might be plants and animals on Mars.
My blog: https://frankhubeny.blog/
I didn't know that!
Interesting article, DW. I think all the conquests start with the adventures of the imagination.
"I seemed to have sensed also from an early age that some of my experiences as a reader would change me more as a person than would many an event in the world where I sat and read. "
Gerald Murnane, Tamarisk Row
I didn´t know that either. Again it reminds me of the beginning of the Modern Age when people thought the oceans were full of monsters.
"I seemed to have sensed also from an early age that some of my experiences as a reader would change me more as a person than would many an event in the world where I sat and read. "
Gerald Murnane, Tamarisk Row
Using math to investigate possibility of time travel
"After some serious number crunching, a researcher says that he has come up with a mathematical model for a viable time machine: a Traversable Acausal Retrograde Domain in Space-time (TARDIS). He describes it as a bubble of space-time geometry which carries its contents backward and forwards through space and time as it tours a large circular path. The bubble moves through space-time at speeds greater than the speed of light at times, allowing it to move backward in time."
https://www.sciencedaily.com/release...0427091717.htm
"I seemed to have sensed also from an early age that some of my experiences as a reader would change me more as a person than would many an event in the world where I sat and read. "
Gerald Murnane, Tamarisk Row
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