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Ken Tapping –
July 16, 2018/1 pm | story:
231156
Photo: You Tube
One of the most fascinating videos sent by the Curiosity rover, which is currently exploring the surface of Mars, shows a number of sandstorms parading through the desert.
Dust storms are common on Earth, but it's exciting to see them on another world, with weather, geography and geology – just like ours.
The likeness of Mars to our world was realized centuries ago. Until recently, we thought that she had a plant life and fantasized about her inhabitants
The other thing that fascinated us was that the planet had what we would call time.
Although Mars is smaller than Earth and further away from the sun Like the Earth, it has polar ice caps, seasons and clouds in its atmosphere.
On occasion, sandstorms cover most of the planet. The landers on the surface show a desert with frost forming on the rocks during the night and evaporating in the morning sun.
There are two other differences between Earth and Mars. The Earth has a thick and wet atmosphere and Mars has a thin and dry atmosphere. The thick and humid atmosphere of the Earth traps heat and reduces daily and seasonal temperature variations.
The atmospheric pressure of Mars at the surface is about half a point of that of the Earth and the Martian atmosphere is much drier. It has very little ability to trap heat.
When the sun rises, dry Martian deserts warm up quickly, warming the atmosphere in contact with it, setting up a vigorous convection. The cold "air" over the highlands flows downward in the form of strong winds.
When the air goes down, it compresses and heats up, like the Chinooks. He climbs and lets cold air flow.
The result is a wind system that can be small or huge. Winds in the fine Martian atmosphere are not able to blow up heavy objects, as hurricanes and tornadoes do on our world. However, they are very good at picking up the sand and dust that cover most of the Martian surface.
The result is dust and sandstorms that can be small and local or large enough to cover the planet. They can be thick enough to completely hide the sun from anyone on the surface for days, weeks or months. This poses us a major problem.
Although Curiosity, our main Mars Explorer robot, is nuclear powered, others, like Spirit and Opportunity, are powered by solar energy. The two landed on Mars in 2004. Spirit has stopped working, but Opportunity is still exploring, after 14 years, much longer than expected.
Opportunity survived a dust storm in 2007, which forced it to go into hibernation until the return of the sun restarted its power supply. However, there is now a dust storm on Mars that is much larger than the 2007 event, which started just above the rover, so Opportunity is likely to be in the air. darkness for much longer.
It can go into deep hibernation but there is a limit as to how its electronics can be obtained and for how long.
Another problem with dust is that it is fine and very dry. By blowing, it charges electrically and hangs on everything. It can cover solar cells and penetrate mechanical and electrical places where it is not useful.
With a bit of luck, a bit of dust-free wind after the dust storm will extinguish everything, as in 2007.
Dust storms are visible, often with very small telescopes, from the Earth. Moreover, it is the right moment to release the telescope
We have just pbaded Mars in its orbit and we are still close to the planet.
Look for a bright orange-red object in the Southeast around midnight. , shining like a lamp.
Mars never seems really big in small telescopes. However, be patient, and there will be times when the air stops, reflections disappear and details suddenly appear.
While you have the telescope, there are other planets to see.
- West after sunset
- Jupiter in the southwest and Saturn in the southeast after dark
- The moon will reach the first quarter on the 19th.
Ken Tapping –
July 9, 2018/3 pm | story:
230529
Photo: You Tube
One night, a few years ago, I received a phone call from a rather worried man.
He lived a few kilometers north of the place where I live. He said that his children had entered the house enthusiastically saying that there were three disc-shaped objects that were spinning on Giant's Head, an extinct volcano south of his house.
He was naturally skeptical, but went out to see, and said that there were three records up there, doing exactly what his kids were saying. Giant's head is to the north, so I said I would go out to look for myself, on the other side of the mountain.
There were three discs spinning in the sky. However, on my side of the mountain, I could see what he and his children could not do.
A local car dealership had three search lights pointing in the northern sky, and waving them around, and there was a very thin layer of, glossy cloud, an ideal movie screen.
Every year, we receive reports of "lights in the sky". People see something unusual in the sky and report it, then we try to determine what it may have been. Sometimes we succeed, and often we do not.
Although extraterrestrial spaceships can not be totally excluded, the main cause of unresolved reports is not enough information, with the additional question of weeks or months report. Here are some suggestions:
What does it look like: size, brightness and color? Note that a shiny, star-like object, like a shining planet like Venus, Jupiter or sometimes Mars, may look bigger in the sky than it actually is.
Where is it in the sky?
If you know your constellations, sketch out your position in relation to at least three bright stars identified. Otherwise, give the position as a bearing and elevation of the compbad (angle above the horizon); for example, Southwest, 30 degrees elevation.
To estimate angles, use your hand at arm's length. Hold your thumb and little finger as far as you can get them.
- From thumb to fingertip of about 25 degrees
- The tip of your index finger up to the tip of your little finger is about 15 degrees
- ] The width of your finger A closed fist is about 10 degrees
- Three middle fingers extend together around five degrees
- The width of your little finger is about one degree
"Guesstimates" made to the eye are usually useless.
Note the time and date.
Does it move? In which direction? How fast? Use the technique of the angle of the hand and a watch.
Does he travel on a fixed route? Artificial satellites cross the sky at about the same speed, or slower than high altitude planes.
Except if it is otherwise, the satellites are generally launched towards the east to capture 1000 km / h of the Earth's rotation. see them cross the sky in a very approximate west-east direction.
Some satellites are launched in polar or near-polar orbits, crossing the sky in a more or less north-south direction.
If he does not seem to be moving, note where he stands in relation to a flagpole, a chimney, a tree or some other reference item and check again one hour later, starting from same place. If it's moved a little to the west, it's probably a celestial object, like a star or a planet.
The Earth is orbited by a large number of satellites with highly reflective antennas. These can capture the sunlight and reflect it in your direction.
You'll see something slowly moving in the sky, brightening it until it's incredibly bright, then fading into invisibility after a few seconds .
If you see something strange in the sky, check all the things listed here, plus anything else you notice, and write it down as soon as possible. Write down the exact time and date.
Otherwise, nothing can be done with your observation.
Finally, report it promptly. Then your information can be combined with other reports, with more chance that we can know what you have seen.
- After dark, Venus is low in the west, Jupiter in the southwest, and Saturn in the southeast.
- Mars, bright and red, rises around 11 pm
- The moon will be new on the 12th.
Ken Tapping –
June 30, 2018/3 pm | story:
229975
Photo: You Tube
Shark Bay, Australia
In the shallow waters of Shark Bay, Australia, we find strange mushroom-shaped rocks called stromatolites. They are produced by living creatures.
Millions of bacteria form sticky carpets that trap particles of sand and mud. The bacteria then develop through it to form a new layer, and the rock structure becomes larger and larger.
A cross section of one of the "mushrooms" shows the layers as dark circles. These structures are really robust and incorporate with the rocks over time as fossils.
Circlet – like structures are found in rocks dating back 3.7 billion years, which shows that liquid oceans existed at the time, while the sun at the time of. Conversely, if things were not frozen in solid state, our brighter sun means we should be frying now. That this is not the case indicates how living things change their environment to adapt to themselves, up to a certain point.
This idea was first proposed by James Lovelock, who suggested that the evolution of living creatures is not only a process of adaptation to their environment, but also an evolution their environment according to their environment.
Living creatures have changed the atmosphere. When life appeared, the atmosphere was rich in methane and carbon dioxide, two greenhouse gases. This made our planet hot when the sun was lower
Plants absorb carbon dioxide and use sunlight to convert it into carbohydrates, releasing oxygen, which is not not a greenhouse gas. Over time, the sun has cleared up and the plants have removed more and more carbon dioxide, replacing it with oxygen and stabilizing the Earth's temperature.
The idea that living creatures can involve themselves in a small terraforming life on other planets.
On Earth, to a large extent, the proliferation of plant life depends on the intake of carbon dioxide. Animals, like us, depend on oxygen for living, breathing carbon dioxide. The more plants there are, the more oxygen there is, which allows more animals to live, producing more carbon dioxide.
Oxygen is very responsive, which is why it is so helpful to our vital processes. It also means that it would quickly disappear from our atmosphere by combining iron and other elements, unless it is continuously supplemented.
On Mars, the atmosphere is very thin, but there is 95% carbon dioxide 0.1 percent oxygen and occasional intriguing traces of methane. There is no real evidence of a biosphere.
Did Mars have a biosphere in the distant past? There is evidence that there was once liquid water on its surface, forming rivers and lakes, which in turn requires a thicker atmosphere than now. In addition, the fact that Mars is often called the red planet is another clue.
The red comes from iron oxide, suggesting that Mars originally had a lot more oxygen in its atmosphere. The red rocks in many parts of our world are stained from iron oxide, formed when the plants have flooded the atmosphere.
This idea of environmental modification suggests that our life develops like ours. greenhouse gases with oxygen.
We often think that red dwarf stars are good places for life-carrying planets, because they are so stable. However, this would mean that life forms that absorb carbon dioxide would cool their worlds, making them less habitable.
They would never share the fertility of our world by producing plants and animals. We should seek life like ours on planets like ours orbiting suns like ours.
- After sunset, Venus shines to the west; Jupiter lies to the south and Saturn to the southeast
- Mars, shining and red, and just after approaching us nearest, rises around midnight.
- The moon will reach the last quarter on 4.
Ken Tapping –
June 23, 2018/1 pm | story:
229620
Photo: wikia.com
In 1967, a Cambridge graduate student, Jocelyn Bell, studied how the solar wind twinkles distant radio sources.
These observations can tell us how fast the wind blows and the size and density of the irregularities in it. However, the output of the tailor made radio telescope showed something else; at one time during the day, there were groups of small spikes regularly spaced.
The south of Britain is densely populated and with a higher population density, more cars, electric motors, electrical interference and all other unwanted radio transmissions. people do. It may not be surprising that radio interference has occurred.
These spikes, which Bell called "scruff," occurred every day at the same time, which gave the impression that it was coming from an agricultural vehicle when it was coming back. at home. In the evening. First, he was an unusually punctual farmer.
However, over time, something happened that upset that idea. The skin was rising four minutes earlier each day
Our measurement of time is based on the apparent movements of the sun. A complete orbit around the sun is called a year, and the time interval between two consecutive noon is called a day, and is divided into 24 hours.
However, as we go around the sun, the direction in which the sun sets at noon changes about one degree a day. So, between two consecutive noons, the Earth turns a little more than a revolution.
If you notice the time a star goes south, and when it's south the next night, you'll see that the time difference is 23 hours. and 56 minutes
This is because the stars are so far away, that they are always in the same direction and that they would appear to the south after exactly one complete revolution of the Earth, not a revolution and a little. The skin originated somewhere far in interstellar space.
The pulsations constituting the skin were exactly 1.33 seconds apart, stable, like a clock. To rule out the possibility that it is some sort of technical quirk, the observation was verified with the help of a different radio telescope
. it was real and it was cosmic. On Earth, we usually produce regular pulsed radio transmissions.
Are these impulses produced by extraterrestrial civilizations, perhaps as "cosmic lighthouses" for interstellar travelers?
With a bit of humor, the object became LGM-1, with LGM for "Little Green Men". Then, more of these mysterious pulsating radio sources were discovered. Fortunately, a non-alien theory for these objects was already available.
In 1934, astronomers Walter Baade and Fritz Zwicky postulated that when an aging giant star dies in a huge explosion, known as a supernova, the central region of the star can be squeezed if strong that the atoms that compose it collapse completely.
Electrons are forced into the nuclei of atoms, forming neutrons. Something the size of a star would be compressed into a neutron ball of about 10 kilometers in diameter. Much of the star's magnetic field is also stuck in this ball of neutrons.
Reducing the size of the star accelerates its rotation from once a month to a few seconds or even fractions of a second. The magnetic field and the fast rotation make producing two radio emission beams, and each time the beam sweeps our direction, we get a pulse, just like the flash we see from a lighthouse.
The light is on all the time, but we see a flash when it points our way. Many of these objects, now known as "pulsars," have been found, some of them being obviously amidst exploding stars
I've rather liked it. 39, idea of Little Green Men and their cosmic lighthouses. ] After sunset, Venus shines brightly in the west
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