On the Nature of Things | Forum

Sparky wrote:Congratulations, NASA for sending a great big genuflecting remote control car to Mars. With lasers. How they managed to pull off this Heath Robinson* scheme is quite incredible:

After the parachute has significantly slowed the vehicle and the heatshield (that has protected the rover during entry) separates, the descent stage will separate from the backshell. Using four steerable engines, the descent stage will slow the nested rover down even further to eliminate the effects of any horizontal winds. When the vehicle has been slowed to nearly zero velocity, the rover will be released from the descent stage. A bridle and "umbilical cord" will lower the rover to the ground. During the lowering, the rover's front mobility system will be deployed so that it is essentially ready to rove upon landing. When the on-board computer senses that touchdown is successful, it will cut the bridle. The descent stage then pitches away from the rover and powers away at full throttle to a crash-landing far from Mars Science Laboratory.

*Rube Goldberg to our Yanqui cousins

Typhoon wrote:

Sparky wrote:Congratulations, NASA for sending a great big genuflecting remote control car to Mars. With lasers. How they managed to pull off this Heath Robinson* scheme is quite incredible:

After the parachute has significantly slowed the vehicle and the heatshield (that has protected the rover during entry) separates, the descent stage will separate from the backshell. Using four steerable engines, the descent stage will slow the nested rover down even further to eliminate the effects of any horizontal winds. When the vehicle has been slowed to nearly zero velocity, the rover will be released from the descent stage. A bridle and "umbilical cord" will lower the rover to the ground. During the lowering, the rover's front mobility system will be deployed so that it is essentially ready to rove upon landing. When the on-board computer senses that touchdown is successful, it will cut the bridle. The descent stage then pitches away from the rover and powers away at full throttle to a crash-landing far from Mars Science Laboratory.

*Rube Goldberg to our Yanqui cousins

Congratulations, indeed.

Hoosiernorm wrote:

Typhoon wrote:

Sparky wrote:Congratulations, NASA for sending a great big genuflecting remote control car to Mars. With lasers. How they managed to pull off this Heath Robinson* scheme is quite incredible:

After the parachute has significantly slowed the vehicle and the heatshield (that has protected the rover during entry) separates, the descent stage will separate from the backshell. Using four steerable engines, the descent stage will slow the nested rover down even further to eliminate the effects of any horizontal winds. When the vehicle has been slowed to nearly zero velocity, the rover will be released from the descent stage. A bridle and "umbilical cord" will lower the rover to the ground. During the lowering, the rover's front mobility system will be deployed so that it is essentially ready to rove upon landing. When the on-board computer senses that touchdown is successful, it will cut the bridle. The descent stage then pitches away from the rover and powers away at full throttle to a crash-landing far from Mars Science Laboratory.

*Rube Goldberg to our Yanqui cousins

Congratulations, indeed.

Not everyone is pleased

Typhoon wrote:

Sparky wrote:Congratulations, NASA for sending a great big genuflecting remote control car to Mars. With lasers. How they managed to pull off this Heath Robinson* scheme is quite incredible:

After the parachute has significantly slowed the vehicle and the heatshield (that has protected the rover during entry) separates, the descent stage will separate from the backshell. Using four steerable engines, the descent stage will slow the nested rover down even further to eliminate the effects of any horizontal winds. When the vehicle has been slowed to nearly zero velocity, the rover will be released from the descent stage. A bridle and "umbilical cord" will lower the rover to the ground. During the lowering, the rover's front mobility system will be deployed so that it is essentially ready to rove upon landing. When the on-board computer senses that touchdown is successful, it will cut the bridle. The descent stage then pitches away from the rover and powers away at full throttle to a crash-landing far from Mars Science Laboratory.

*Rube Goldberg to our Yanqui cousins

Congratulations, indeed.

Ki_Af_o9Q9s

A technological tour de force.

PASADENA, Calif. – An image from the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance orbiter captured the Curiosity rover still connected to its 51-foot-wide (almost 16 meter) parachute as it descended towards its landing site at Gale Crater.

"If HiRISE took the image one second before or one second after, we probably would be looking at an empty Martian landscape," said Sarah Milkovich, HiRISE investigation scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "When you consider that we have been working on this sequence since March and had to upload commands to the spacecraft about 72 hours prior to the image being taken, you begin to realize how challenging this picture was to obtain."

Universe was 'born in a big chill'

The early universe can be likened to water that froze into ice and cracked as it cooled, say a team of Australian scientists.

James Quach, from the University of Melbourne, and colleagues, calculated how light would be scattered in space by cracks in the universe.

Their results appear in the journal Physical Review D.

"We believe that when the universe cooled, cracks would have formed in space, and these cracks we believe are observable, says Quach, who did the research as part of his PhD.

"We worked out a way that we can test this model."

If proven correct, the predictions could revolutionise the way we view the birth of the universe..

Honor his example of service, accomplishment and modesty, and the next time you walk outside on a clear night and see the moon smiling down at you, think of Neil Armstrong and give him a wink.

Let's hope we DON'T find water on Mars: Nasa's mistake installing drill means we may end up contaminating the planet with microbes


When the Curiosity finally extends its drill and bites into the dusty surface of the Red Planet, Nasa scientists will be quietly hoping that the Mars rover will not find ice beneath the surface.

For if it does, it will blow open a scandal that has been 'simmering' inside Nasa for the last year: the fact that the drill bits may well be infected with Earth bacteria - bacteria which could survive on Mars.

The possible contamination occurred six months ago, when engineers peeked inside the drill mechanism without permission in order to attach one more piece.

If the drill touches water, there is every chance the bacteria could live.


This would be a crisis for Nasa: to meddle with the biological make-up of planet which, for all we know so far, may still have native microbes of its own kind.

According to the LA Times, Nasa does not expect to find water - the space agency chose the dry equatorial landing site in Mars' Gale Crater to study the planet's geology, not in a bid to find water or ice.

But, the paper adds: 'If by chance the rover Curiosity does find H2O, a controversy that has simmered at NASA for nearly a year will burst into the open.'

The potential contamination occurred on November 26 last year, after the drill bits had been sterilised and placed in a box, which would not be opened again until a successful touchdown on Mars.

But engineers were worried that a rough landing could damage the drill bits - and opened the box to add one more drill bit and increase their chances of success.

According to the LA Times, the engineers screwed the drill bit directly into the drill - so that if the loading mechanism failed, Curiosity at least had one shot of a successful dig.

Alpha Centauri Bb is an extrasolar planet orbiting the K-type star Alpha Centauri B approximately 4.37 light-years from Earth, in the southern constellation of Centaurus.[1] It is the closest exoplanet to Earth ever discovered, and the least massive orbiting a star similar to the Sun.[2]
Characteristics

The planet is not in the habitable zone, orbiting very close to the host star at just 0.04 AU and completing one orbit every 3.236 days.[1] It has a mass of at least 1.13 times that of Earth; only a lower limit is currently known because of lack of knowledge of the planet's orbital inclination.[1] Bb's surface temperature is estimated at least 1200 °C (~1500 K),[3][4] far too hot for liquid water and also above the melting temperatures of many silicate magmas. For comparison, the surface temperature of Venus, the hottest in the solar system, is 462°C (735 K).

Earth began passing through a stream of debris from Halley's Comet on Oct. 15, which gives us the benefit of the annual Orionids meteor shower—though you probably won't see much until a bit later.

The shower should be at its peak the night of Saturday, Oct. 20, until just before dawn on Oct. 21. This year, the moon will be setting at approximately midnight, which will keep the sky darkened enough that—barring cloud cover—you should be able to see 15 to 30 meteors per hour, according to Astronomy.com.

This is when and where the website indicates that viewing is best, according to Astronomy.com:

When: Saturday night into early Sunday morning, Oct. 20 and 21, from midnight to 2 a.m.
Where to Look: Before midnight, look halfway up to the east; between midnight and 2 a.m., look overhead; from 2 a.m. to dawn, look halfway up in the west. (The meteors will appear to radiate from Orion.)
Suggestions on Where to Watch: The current weather forecast calls for clear skies so any dark location with a clear view of the sky should work. City parks are closed during those hours.
Bring: Lawn chairs, blankets, sweatshirt, snacks

What makes this shower so cool? First of all, c'mon—it's a show of shooting stars.

Also, though, there's no question about where to look for this one. Meteor showers get their names from the constellations in the sky where they can be spotted. And what's easier to spot than Orion the Hunter?

The stars tend to shoot from Orion's club, pierce Taurus the Bull, the Gemini twins, Leo the Lion and finally, Canis Major, home of Sirius, the brightest star we can see—well, aside from the sun.

There's also something else that's special about this show: With the second-fastest entry velocity of all the annual meteor showers, meteors from the Orionids produce yellow and green colors and occasionally produce an odd fireball.

Crocus sativus wrote:.

" Why the World Didn't End Yesterday "



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monster_gardener wrote:.

Not much Moon to interfere.

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"This discovery is in keeping with our emerging view that virtually every star has planets, and that the galaxy must have many such potentially habitable Earth-sized planets. They are everywhere, even right next door," said a statement from Steve Vogt, of the University of California, Santa Cruz, who is the co-author of the discovery, due to be published by the reputable journal Astronomy and Astrophysics.

[..]

"Tau Ceti is one of our nearest cosmic neighbours and so bright that we may be able to study the atmospheres of these planets in the not-too-distant future," James Jenkins, of the Universidad de Chile and the University of Hertfordshire, said in a statement.

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A group of American-Russian scientists have found several types of bacteria from Siberian permafrost, which can grow in harsh conditions similar to those on Mars. It could potentially mean that Earth microbes can survive on the Red Planet.

Some of the genus Carnobacterium microbes have already been found to exist in cold climates around the world – such as Alaska and in the oxygen-poor waters of Ace Lake in Antarctica.

Researchers from the Department of Microbiology & Cell Science at the University of Florida took samples of bacteria from the sand deposits, on the bank of the Kolyma River in northeastern Siberia.

After extracting the samples from a depth of 12-20 meters where the soil has an average annual temperature of -7 °C, scientists grew bacterial colonies at 28 °C in normal atmospheric conditions.

The bacteria were then tested in Martian conditions – exposed to a lack of oxygen, extremely negative temperatures, and very low pressure – which hinder the growth of most terrestrial microorganisms.

After the 30-day experiment, only six of the 10,000 isolates were able to grow under these conditions.

All of the surviving isolates were members of the genus Carnobacterium- as reported by the scientific quartet of Wayne L. Nicholson, Kirill Krivushin, David Gilichinsky and Andrew C. Schuerger , in the journal "Proceedings of the National Academy of Sciences."

Prunus persica wrote:

monster_gardener wrote:.

Not much Moon to interfere.

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Good news for Monster


Potentially habitable planet discovered orbiting nearby star similar to our sun

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"This discovery is in keeping with our emerging view that virtually every star has planets, and that the galaxy must have many such potentially habitable Earth-sized planets. They are everywhere, even right next door," said a statement from Steve Vogt, of the University of California, Santa Cruz, who is the co-author of the discovery, due to be published by the reputable journal Astronomy and Astrophysics.

[..]

"Tau Ceti is one of our nearest cosmic neighbours and so bright that we may be able to study the atmospheres of these planets in the not-too-distant future," James Jenkins, of the Universidad de Chile and the University of Hertfordshire, said in a statement.

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Good news for Monster

Typhoon wrote:You call that an earthquake? This is an earthquake

The ISS is partially protected from the space environment by the Earth's magnetic field. From an average distance of about 70,000 km, depending on Solar activity, the magnetosphere begins to deflect solar wind around the Earth and ISS. However, solar flares are still a hazard to the crew, who may receive only a few minutes warning. The crew of Expedition 10 took shelter as a precaution in 2005 in a more heavily shielded part of the ROS designed for this purpose during the initial 'proton storm' of an X-3 class solar flare,[241][242] but without the limited protection of the Earth's magnetosphere, interplanetary manned missions are especially vulnerable.

Subatomic charged particles, primarily protons from cosmic rays and solar wind, are normally absorbed by the earth's atmosphere, when they interact in sufficient quantity their effect becomes visible to the naked eye in a phenomenon called an Aurora. Without the protection of the Earth's atmosphere, which absorbs this radiation, crews are exposed to about 1 millisievert each day, which is about the same as someone would get in a year on Earth, from natural sources. This results in a higher risk of astronauts' developing cancer. Radiation can penetrate living tissue, damage DNA, and cause damage to the chromosomes of lymphocytes. These cells are central to the immune system and so any damage to them could contribute to the lowered immunity experienced by astronauts. Radiation has also been linked to a higher incidence of cataracts in astronauts. Protective shielding and protective drugs may lower the risks to an acceptable level.[37]

The radiation levels experienced on ISS are about five times greater than those experienced by airline passengers and crew. The Earth's electromagnetic field provides almost the same level of protection against solar and other radiation in low Earth orbit as in the stratosphere.