Stars Are Cool. No, Really, They Are


When the gringa’s dear readers think of a star, what do you think of? The Sun? Polaris? Alpha Centauri?  And what do you think would happen if you reached out to touch the Sun? You’d probably get vaporized, right? Well, depending on the star, not necessarily. In fact, if you touched the right star it might be a sensation more like when you roll over in bed and find the cool spot.

Brown dwarfs are cold stars. There are 14 that NASA believes are cool enough to touch. Cool! They are also the oldest stars in the Universe. I guess stars are kind of like people. Old folks with poor circulation are generally cold all the time. Stars get old and cold, too. Out of all the old, cold, brown dwarf stars in the Universe, it’s the Y-dwarfs that are even cooler than the average human’s body temperature. Y, you may ask. Well, the gringa will tell you why the Y is the way that it is.

Not only are they old but they are failures. Poor Y-dwarfs. They must have very low self-esteem. Perhaps that is why they don’t shine as brightly as other stars. They have grown old and are failures as stars. The gringa feels very sorry for the poor, little things.

Because their cores are not very dense they can’t fuse loads of atoms within. That means they don’t burn as hot and brightly as other stars. The gringa finds it very amusing that the denser a star is the brighter it is. It doesn’t seem to work that way in humans.

If Y-dwarfs are such failures at being stars, the gringa wonders if they should be considered stars at all. Do we have a Pluto prospect in the future? Just as Pluto got demoted from planet to dwarf planet, Y-dwarf stars may very well face the possibility of being re-classified. In the future scientists may decide they don’t meet all the guidelines of being a star. The gringa thinks this is a wonderful possibility for Y-dwarfs. Whereas poor Pluto suffered a demotion, the Y-dwarf could get better news. They could go from being failures as stars to being over-achievers for whatever it is they may become!

However, it may take astronomers quite some time to collect enough data in their studies. Their failure to shine bright like a diamond in the sky means it is difficult to view and study them. It’s practically impossible to study them at all with a telescope dependent on visible light. To take productive peeks at Y-dwarfs NASA had to construct an infrared telescope and mount it to an orbiting satellite. And that is why the Universe is wiser thanks to these cold, little star failures, because of Wide-field Infrared Survey Explore (WISE) that studies them in the heavens.

Source:  www.nasa.gov

Image Credit:  www.jpl.nasa.gov

 

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Wearable A/C


The gringa considers nudity to be part of the climate change solution. It could solve lots of problems:

  • Conserve water.
  • Reduce emissions with less marketable goods requiring shipping.
  • Reduce energy usage to cool homes in warm climates.

However, some innovators in the fashion industry may have come up with a cool, pardon the pun, solution that will allow everyone to keep themselves covered and still be comfortable despite the heat.

With the invention of plastic based textiles, cooling is all part of the design of a new, innovative fabric that engineers have developed at Stanford University. Combining the disciplines of chemistry, nanotechnology and photonics with an old-fashioned cotton fabric, sweat and body heat pass right through.

Believe it or not, current “breathable” fabrics are simply not breathable at all. People get hot wearing clothes because invisible waves of infrared radiation produced by our bodies are trapped under the clothes we wear. In research studies comparing standard cotton with the new fabric, scientists discovered that good, ol’ “breathable” cotton raised the temperature of skin surface by nearly 4 degrees Fahrenheit (or 2 degrees Celsius). For the gringa, that would make all the difference in the world. I could keep my A/C off and my family clothed in cooling fabrics.

The gringa only sees one problem, the plastic connection. Plastic is, of course, a petroleum based product. Isn’t dependence on petroleum the bane of human existence? Isn’t it at the heart of climate change? Is it not the object of war for profit? So has the science community really come up with a practical solution to help contribute one tiny bit to the climate change solution or has it simply opened a Pandora’s Box for the future of petroleum wars? Will nations continue to slaughter one another in order to control oil fields that will be necessary to keep people clothed in fabrics that will help them survive the catastrophic heatwaves of the future?

 

Source:  stanford.edu

Image Credit:  thumbs.dreamstime.com

 

The Truth About Tabby


UFO and alien conspiracy theory buffs are going to enjoy this post by the gringa, or not. I guess it depends on if you enjoy a healthy dose of conspiracy debunking or truth. You see, dear readers, there has been a bit of hubbub about an interesting space object that is orbiting a nearby star and was detected by the Kepler telescope late last year.

The SETI Institute (Search For Extraterrestrial Intelligence) calls KIC 8462852 “mysterious”. NASA believes the mystery is resolved with the theory that the strange signals are the result of cosmic dust, probably from multiple impacts of a comet swarm, and causes the star’s light to flicker erratically. Vanderbilt University researchers, who affectionately call the star Tabby, debunk theories by those who believe it to be home of aliens who are very, very busy. The astrophysicist contributors to the respectable Astrophysical Journal agree with Vanderbilt’s point of view while at the same time agreeing with theories from other scientists who propose an extraterrestrial origin theory. So, who’s got it right? Who’s got it wrong? Just what the heck is the truth about Tabby?

Who Is Tabby

Tabby is officially designated star KIC 8462852 and shines brighter than our own Sun about 1400 light years from Earth in the Cygnus constellation. It is a subject of study by NASA’s Kepler space telescope which reveals that from time to time it dims about twenty percent in brightness.

SETI’s Conclusion

The cause of the dimming light could possibly be because of material or objects orbiting the star. SETI researchers believe they have evidence to determine that these objects are not planets. SETI considers the possibility that Tabby could be home to a technologically sophisticated society that has constructed a swarm of solar panels that orbit the star which would account for the light fluctuations.

SETI uses its own Allen Telescope Array to study radio signals that originate from that part of outer space. They attest that these radio signals are of artificial origin, calling them “non-natural”. They search for narrow-band signals and broadband that might possibly be produced by a large and powerful spacecraft. They also search for evidence of laser pulses. SETI’s Panamanian partner, Boquete Optical SETI Observatory, performs the laser pulse research.

Research such as this takes a long time so the gringa will have to practice patience for SETI to conclude their studies and publish their final results. They admit that, historically, cases like this usually result in finding a natural cause for the anomalies but they still must investigate the possibility of it originating from extraterrestrial intelligence. That is, after all, their mission.

NASA’s Conclusion

During four years of observation, the Kepler mission recorded strange happenings in 2011 and 2013 when interesting and dramatic light fluctuations occurred. To help determine what happened, NASA also trained the eye of the Spitzer Space Telescope in Tabby’s direction. Kepler observed the visible light. Spitzer could delve deeper into the invisible infrared light signals and patterns. In November of last year Spitzer paid off with a recording of another light fluctuation.

Although NASA’s theory is that clouds of space dust were formed from a swarm of comets that orbit the star in erratic patterns, Spitzer did not discover evidence to support this theory. This caused NASA to switch to a cold comet theory. One lead comet would be followed by a swarm of smaller comets. If this is true, even if the comets were already out of the telescope’s view as they traveled around Tabby, they should still leave behind a detectable infrared signature. However, this was not the case.

Researchers admit that more observations need to be recorded to determine just exactly what is going on. NASA admits that Tabby is strange, indeed. However, they believe that a natural cause is more likely than “little green men”.

Vanderbilt University’s Conclusion

Vanderbilt studies focused on the 100 day period when the most significant light fluctuations occurred. The manner in which they occurred suggested that a large number of “irregularly shaped objects” passed in front of the star causing its light to be blocked temporarily. Working off a report from an astronomer at Louisiana State University who concluded that the star had diminished in brightness by 20 percent over the past century, Vanderbilt finds a natural cause unlikely as an explanation for this. This has become fodder for the theory that a megastructure has been constructed that is absorbing the star’s energy, the solar panel array theory. This is a theory that was reviewed, accepted and published by the Astrophysical Journal.

Vanderbilt, however, did not stop there. They soldiered on. Partnering with amateur German astronomer, Michael Hippke and NASA scientist Daniel Angerhausen, the team began comparing the 20 percent drop in intensity to other stars. They discovered that this is not an unusual phenomenon. In fact, it’s not a star phenomenon at all. It is simply the result of technological changes and advances of human manufactured instrumentation for observance.

The Gringa’s Conclusion

These are all interesting theories but not yet solid answers. So, the gringa will wait and see if, ten or twenty years down the road, we all find out what the actual, final answer is:

  • Comet Swarms

or

  • Extraterrestrial Solar Array

Until then, Tabby will be the most interesting and mysterious star in our night sky.

Sources:

www.seti.org

www.nasa.gov

vanderbilt.edu

Image Credit:  www.centauri-dreams.org

 

Who’s In For A 2-Month Long, Melanoma-Free Day?


As researchers plot their space plans to discover where possibilities lie for a home planet like Earth, that might even be supporting our ancestors, where are they looking? MIT astronomers comprising an international team in Belgium are plotting for a search about 40 light years away. That means if we don’t want a spaceship to arrive with astronauts dead of old age or perhaps affected by age-related dementia, we have to send astronauts in the age group of 20s-40s to manage the forty year flight mission. It may take another decade or two for space agencies to have the ability to travel that far so elementary and middle school children of today are the astronauts of tomorrow that may be slated for just such a mission.

Beyond our solar system is the best bet for finding life like our own, or at least a few planets like ours. An MIT team has discovered three planets that orbit a dwarf star about 40 light years away. Their sizes are about the same as Earth or Venus. The telescope the astronomy used to locate them is the TRAPPIST telescope located in Chile. This telescope is designed to specifically focus on a cluster of dwarf stars, 60 in number.  Belgian scientists created TRAPPIST to study the infrared wavelengths of dwarf stars and the planets surrounding them.

The scientist’s favorite dwarf star is an ultracool (as in thermally ultracool, not socially hip) star about the size of Jupiter and much cooler than our own sun. Beginning a period of observation in September, 2015, the astronomy team observed regular intervals of fading in the infrared signature of the star. They theorized that planets were passing in front of the star causing this to occur.

The team turned their attention to the time to expect a light fade event and discovered that there were, indeed, planets orbiting the star. The two nearest planets were similar in size to our own Earth and Venus. The closest planet that has everyone’s attention is named 2MASS J23062928-0502285, commonly called TRAPPIST-1. The two planets have orbit cycles, respectively, of 1.5 of our own days and 2.4 days. The amount of radiation they absorb from their star is significantly more than what we deal with. The closest one receives about four times the radiation we get and the next one about two times the amount. So, if there is any life there it would have to have evolved with natural radiation tolerance.

The third planet in distance from the star has an unknown orbit cycle. The scientists’ best guess so far is that it could be anywhere from four to 73 days but would receive significantly less radiation. I guess that’s good news. If we need to relocate I suppose we could deal with a four-day long day or even a two-month long day and not have to worry about skin cancer.

When the team analyzes the size of the planets in relation to the star, and take into account their proximity to their sun, they believe that life could be sustainable. They calculate that there could be areas with a temperature range less than 400 kelvins. That converts to about 260 degrees Fahrenheit or 127 degrees Celsius. Not exactly a tropical paradise but conditions where liquid water and organic life could survive.

The next step is to study the atmospheric conditions of the planets to see what their atmospheres are composed of. What kind of gases? Is there breathable oxygen? And they believe that within their own working career’s lifetime they will be able to determine if these planets are inhabited with life of some kind, say the next ten years or so.

This is a breakthrough in science. Traditionally scientists have studied bright solar stars like our own. By taking a risk and searching for a cool dwarf star, this MIT group has hit paydirt with the find of a lifetime. To accomplish their task they had to design a whole new set of instruments specialized to detect the radiation emitted by cold dwarf stars and only visible through an infrared telescope. The whole field of detecting other worlds changed simply by changing the wavelength humans were viewing the galaxy with. Perspective is everything.

Source: news.mit.edu

Image Credit: http://www.storify.com