http://www.universetoday.com/46816/astronaut-on-mars/
I had no idea that the Soviets had though so far ahead. Here are discussed many different stages of development from initial dependence on Earth to ultimate full independence on Mars.
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http://www.universetoday.com/46816/astronaut-on-mars/
I had no idea that the Soviets had though so far ahead. Here are discussed many different stages of development from initial dependence on Earth to ultimate full independence on Mars.
I meant to add a comment on the preceding post. Very interesting on the effect of gravity on different objects, YesNo.
On second thoughts, I'm not sure what this post is saying. I thought that with no gravity nothing "falls", only if someone pushes it with their hand or something.
There's gravity, but since it is in a vacuum there is no air resistance on the feathers to stop them from falling as fast as the heavier ball.
But the idea of "falling" is puzzling me at the moment. If the acceleration depends on mass shouldn't there be some difference between the ball and the feathers although tiny?
Also the idea of light bending when going past a massive object (gravitational lensing) does seem like it could be interpreted as mass giving the surrounding space a higher refractive index. Light also bends when passing through water. This refracting approach to gravitational lensing I got from Maya Benowitz in a comment made to a question about the existence of gravitons: https://www.quora.com/Quantum-Gravit...n-detected-yet
From the top of my head I think it is the water's surface that refracts the light. It travels straight through the water. So I don't know if that model holds up.
I listened to a radio programme today from about 10 years ago on the Graviton, (by podcast) So much has moved on since then. The strange idea of the force of Gravity leaking into other dimensions (explaining why it is so weak ) was mentioned.
Just read your link - I agree that Force carrying particles are a difficult concept and would be even more improbable but for the example of the photon which is so active it can be measured. I don't get where the particle ends (eg the Higgs or the Graviton) and the 'field' begins. I suspect the model in my head is not imaginative enough.
OK, this post is from the journal Popular Astronomy (Sept/Oct 2016). NASA's Messenger Mission is not new, it has been circling Mercury since 2008, and collecting data. The most striking discovery is that Mercury's crust is predominantly made of graphite. A second probe, BepiColombo, is due to be launched in 2018, jointly by NASA and the Japanese Space Agency which will fill out the gaps that Messenger was unable to cover due to its orbit. See http://www.open.edu/openlearn/discovermercury.
I must confess I didn't know anything about the Messenger mission until reading this Popular Astronomy article.
I don´t doubt that the aim of all this space interest is to create interplanetary human colonies. All this research and space expeditions are very expensive.Quote:
Originally Posted by Dreamwoven
I wonder not only when they will be able to start this colonization but what kind of people they will send to space and what will be the survival conditions.
The model in my head is all messed up with bits and pieces from the media. Today, I suspect there is no graviton although a few weeks ago I would have wondered if the graviton had mass just assuming it existed in the first place.Quote:
Originally Posted by prendrelemick
Get your passports ready!
https://www.youtube.com/watch?v=6eirHoHsaQo
Obs. The last question is the one that matters.
Boeing would be a company with resources to do some space research without relying on the taxpayer and governments. Also the ability to send out cubesats reduces the cost of research.
However, I don't see the point of sending human beings on these missions since machines can gather the data better than we can without needing biological and psychological support systems. We should soon have cars and planes that drive themselves. That might be the first step and something that can be done right on Earth: can we get acceptance of self-driving vehicles before the next recession which could slow down such technological change.
Your comment on Boeing was spot on, though perhaps it was discussed locally, as it is based in Chicago.
http://www.universetoday.com/131316/...s-exploration/
There is a lot of interest in Mars, besides Boeing, Musk and other very rich private individuals, other countries are also getting into the race.
http://www.universetoday.com/131360/...pernovae-fail/.
Interesting post, including much that is speculative.
I didn't realize that it was possible for no remnant to remain during a supernova. Not leaving a remnant would be a more efficient way to distribute heavier elements throughout the universe.
The author indirectly emphasized the problem with black holes. In a fraction of a second the star is just gone at least in terms of anything taking up space. All the matter must have been converted into a warping of space-time based on a gravitational theory that has mathematical singularities in it. If I recalled Moffat correctly, even Einstein didn't like that part of his theory and was looking for a way to avoid those singularities because their presence in the theory suggests there is something wrong with the theory at those points.
http://www.universetoday.com/131378/...system-family/
No name, just evidence that there is a previously unidentified planet in the Kuiper Belt.
I wonder if this project to search for planets in the Kuiper Belt could be turned into a distributed computing project. Perhaps it already is. I have one of my old computers working on a distributed project at PrimeGrid that searches for primes in Sierpinski sequences.
I looked up the Sierpinski sequences and its those triangles that fit into each other. All beyond me that is. I only did maths to Ordinary Level General Certificate in school, and scraped a pass in it.
Back to astronomy, this post on http://www.universetoday.com/131403/...ngs-intrigues/ looks fascinating.
I notice it was discovered by the blink of a star. Yesterday I heard of a system being developed that will constantly monitor the whole of the sky, that's billions of stars all at once, and automatically detect any changes. These can then be checked out by astronomers. It is a simple and commonsensicle idea - let the computers do the boring meticulous stuff. If it all works properly, how much other stuff will be discovered.Quote:
Originally Posted by Dreamwoven
So often the story of astronomical discovery starts with a lone astromoner sat on top of a mountain, just happening to notice something unusual.
The computers should be doing the work, but there may be too much data to process and not enough funding for an institution to purchase the needed computing power to complete the tasks. And so one has distributed computing, a kind of crowd sourced research although it doesn't require knowing much about anything in particular to direct one's old computer to a project.
I am trying to imagine a planet with such huge rings. There is an image of it in the Universe Today link above.Quote:
Originally Posted by Dreamwoven
Giant Rings. The rings around J1407b are so large that we could see in the dusk from the earth when they were placed around the planet Saturn. The rings can be seen above the Old Leiden Observatory. Credit: M. Kenworthy / Leiden University
It is nice to know that planetary rings can get larger than we might expect based on the rings around Saturn.
This Giant Exoplanet is orbiting round star some 420 light years from Earth.It was discovered in 2012 and Astronomers were puzzled by the unusual pattern of eclipses it produced, so it was studied in more detail, and the conclusion was that it must be caused by a planet with large rings around it, a giant version of Saturn:
For example, in 2015, the same team concluded that the ring system is one-hundred times larger and heavier than Saturn’s (and may be similarly sculpted by exomoons). And in their most recent study, they have shown that these giant rings may last for over 100,000 years, assuming they have a rare and unusual orbit around their planet.
In their previous work, Rieder and Kenworth determined that the ring system around J1407b consisted about 37 rings that extend to a distance of 0.6 AU (90 million km) from the planet. They also estimated that these rings are 100 times as massive as our Moon – 7342 trillion trillion metric tons. What’s more, while J1407b’s existence is yet to be confirmed, they were able to rule out the possibility of it having a circular orbit around the star.
The study continues...
So they aren't some alien megastructure.
I think we have know that for some time, this explanation, dating from 2012 is much more convincing.
It sure does. And starts is the right word. Newton was desperate for the meticulous observations of Flamsteed so he could work on the moon's orbit. But Flamsteed was as jealous as Newton when it came to his work. Newton had the official influence to basically requisition Flamsteed's work. This crushed poor Flamsteed.Quote:
Originally Posted by prendrelemick
Gauss was professor of astronomy at Gottengen, where he lived in the tower one floor below the observatory. Classic. I don't know how much time Gauss had for observational astronomy. But he was busy inventing instruments for it and improving the ones already on hand with a mighty ingenuity, in addition to devising better ways to mathematically interpret astronomical data.
When the data is in the hands of a good mathematical physicist, a theory becomes possible. Figuring out those rings was awful smart. Gauss is the kind who could have done it. If we had him today he might just solve the dark energy/matter conunndrum, or make a great deal of progress on it. He is at the top of the class for mathematical astronomy of all time. Dang it, I want Gauss or Newton back. Statistically, though, we should have a mind as great as theirs working on these problems today with our gigantic world population participating, while all of that pair's discoveries came about with only Europe participating when it had a paltry population of a couple of hundred million.
Some of the missing pieces will be provided by observational astronomy. Insufficient observation at first supported the idea that the expansion of the universe was slowing down. Presumedly better observation supports the idea that it is speeding up. Even better observation that accounts for something unaccounted for in present observations could well leave Einstein's theory of gravitation intact. The fruits of refined observation are the most frequent cause of new astronomical theories, as far as I can tell, and the most frequent cause of refinement to the ones that already exist.
http://www.space.com/34380-bizarre-p...n-reverse.html
This is worth reading!
It seems that the reason they think the rings rotate in the opposite direction is because they are still there for us to observe. Otherwise they would have been thrown off during the early period of that system's existence.
I don't follow you, YesNo. What would have been thrown off, the rings?Quote:
Originally Posted by YesNo
I think that is what Rieder was saying when he was quoted. I may have misunderstood him. The ring system would be unstable if it moved in the same direction as the planet. If it is a ring, then it would have to go in the opposite direction we expect. Or perhaps it is not a ring but something else.
The ring moving in an opposite direction to the planet is intriguing. I never even thought of that before. What do the rings of Saturn do?
I think it is very rare that rings move in an opposite direction, the result of a catastrophic event:
How such a ring system could have come about is a mystery, as retrograde ring systems are quite uncommon. But Rieder and Kenworth have stated that they think it might be the result of a catastrophic event – such as a massive collision – that caused the rings (or the planet) to change the direction of their rotation. (http://www.universetoday.com/131403/...ngs-intrigues/).
That's all we know at this point in time.
New Horizons is on its way deeper into the Kuiper Belt. It is heading for this odd-shaped object. Visit this space.com article for more details: http://www.space.com/34429-new-horiz...red-color.html
The object is very peculiar, as can be seen from the picture.
http://www.universetoday.com/131597/...as-comet-came/
This is an interesting post, it plots the orbit of rosetta's comet, based on what we know of its movements while being tracked by the probe.
We'll get to see how close the artist's rendering of the object is to the actual data coming back.Quote:
Originally Posted by Dreamwoven
Yes, and this is how it was for New Horizons when it passed Pluto. All we knew is that it was a dot in the sky. We are still receiving data analyses from around the world, earthquakes, landslides, volcanic eruptions, its quite a remarkable catalogue. The same can happen again, with this much smaller object. it will indeed be exciting to see the results.
The moons of Mars - Deimos and Phobos - there is an explanation, worth reading: http://www.universetoday.com/14908/mars-moon-deimos1/
Moons are still being discovered around Uranus:
The SOCIETY for POPULAR ASTRONOMY
Electronic News Bulletin No. 432 2016 October 23
POSSIBLE ADDITIONAL MOONS AROUND URANUS'S RINGS
University of Idaho
After re-examining data acquired by the Voyager 2 spacecraft,
astronomers have detected wavy patterns in two of Uranus's rings --
patterns that may be indicative of two undiscovered moons. Like the
other gas giants in the Solar System, Uranus has a ring system, though
it is not nearly as spectacular as the one around Saturn. And like
the other gas giants, Uranus has a lot of natural satellites -- 27 are
now known. New research suggests that that number might have to be
revised; data collected by Voyager 2 during its historic 1986 fly-by
hint at two undiscovered moons lurking near a pair of Uranus rings.
The suspected new moons reside in Alpha and Beta -- the 5th and 6th
rings. Voyager 2 found 10 moons when it visited the planet in 1986,
tripling the number of moons known to orbit the gas giant. The two
rings exhibit a series of wavy patterns consistent with the presence
of two tiny moons. The patterns may be wakes from small moonlets
orbiting outside those rings. Importantly, the observations are
consistent with how Uranus's other moons, such as Cordelia and
Ophelia, are exerting gravitational pressure on the dust, rocks, and
ice within the rings, herding the particles along a narrow formation.
If the now-postulated moons exist, they are quite dark and small,
measuring only 4 to 14 km across. That would make them smaller than
any other known moons orbiting the planet, which explains why Voyager
2 did not detect them directly. The researchers are now planning to
inspect Uranus with the Hubble telescope.
Those possible, tiny moons around Uranus makes me wonder what criteria distinguishes a moon from one of the particles in a ring.
Perhaps the Hubble 'scope will be able to produce more info. But ultimately, rings and moons probably shade into one another?
Perhaps the Hubble 'scope will be able to produce more info. But ultimately, rings and moons probably shade into one another?