fun facts about gliese 436 b

By januari 11, 2021Uncategorized

In a press release from the University of Warwick, a team of researchers revealed that some of the planet is evapotating due to pressures exerted on it by its parent star. The planet is about 4000 km larger in diameter than Uranus and 5000 km larger than Neptune and a bit more massive. I understand and agree that registration on or use of this site constitutes agreement to its User Agreement and Privacy Policy, In a press release from the University of Warwick. 1. Mail2Day: 12 Interesting Science Icon Facts. Burning Ice Planet (Gliese 436 b) – Machprinciple.com. Consisting of ethyl formate, this is the same gas that gives raspberries their taste and rum its smell. Scientists therefore proposed that a thin layer of helium and hydrogen covers the entire ice layer. It about 20 times bigger that Earth, and is roughly the size of Neptune. 19. 10. Gliese 436 b is a massive contradiction. However, here is something that will put even science fiction to shame – an exoplanet that is covered with a layer of hot ice. SOURCE. That’s because Gliese 436 b is a ball of ice which exists at a seemingly impossible temperature of 439 degrees celsius. However, the measurement of the radius during the planet’s transit across its star, it was fond that ice alone was not enough to give the planet its radius. 6. HAT-P-11b; 55 Cancri e; Gliese 581 b; Gliese 876 d; Rujukan Pautan luar. It was first recorded transiting its star in 2005 but not much importance was paid. Spitzer Space Telescope studied the brightness temperature of the planet and found thermochemical disequilibrium in its atmosphere. So, how water can remain solid at these temperatures? Gliese 436 b. Astronomers believe that it embodies exotic states of water that causes its surface to be covered in burning ice. and it would be worth $26.9 nonillion Planet Gliese 436 b is an ice planet that is constantly on (ire do to … Save my name, email, and website in this browser for the next time I comment. Instead of hydrogen, it could have relatively large amounts of heavier molecules such as water vapor, carbon monoxide, and carbon dioxide, which would compress the atmosphere and make it hard for us to detect any chemical signatures.”. This planet has almost the size of Neptune. Even more perplexing is the fact that scientist say the planet was actually formed as a gas giant and was way far from the host star than its current position. 16. Because of the immense gravity, the ice is prevented from being vaporized despite the temperature being more than 4 times higher than the boiling point of water. 2. They found that 581b weighs 16.6 times as much as the Earth, and that its orbit around GL 581 lasts for 5.366 days. And therein lies the second mystery — carbon monoxide should not be present to this degree, as it becomes scarce when temperatures soar above a certain threshold. 3. In 2007 an exoplanet named Gliese 436b was discovered. Gliese 436 b (disebut /ˈɡliːzə/), or GJ 436 b, adalah planet luar suria yang mengorbit bintang kerdil merah Gliese 436. -40 Celsius and -40 Fahrenheit are the same temperature. 1. 4. The diameter of Gliese 436 b is 5000 kilometers larger than that of Neptune. Gliese 436 b was discovered in August 2004 by R. Paul Butler and Geoffrey Marcy of the Carnegie Institute of Washington and University of California, Berkeley, respectively, using the radial velocity method.Together with 55 Cancri e, it was then the first of a new class of planets with a minimum mass (M sini) similar to Neptune. How the heck is that possible? Gliese 581c is the third planet in order from its host star. It travels at a distance of 4,000,000 kilometers from its star. Known to be one of the smallest exoplanets, Gliese 436 b is about 30-light years away from us. Gliese 436 b is another murderous planet under the Gliese catalogue. Gliese 581g has a mass of around 3 to 4 times that of Earth, its radius is thought to be around 1.5 times larger. It is 2.5 million miles away from the star it orbits. The star is orbited by one known planet, designated Gliese 436 b. Fortney works at NASA Ames Research Center, Moffett Field, California. It is 36 million miles away from the sun (Gliese 436b) The radius 71,500 The density 1.51 cubic gram The surface gravity is 1.18 Gliese Based on information collected about size and mass of Gliese 436 b during its transit, scientists came to the conclusion that the planet was mainly composed of water. SOURCE. Some call it the burning ice planet but actually there is no fire. 14. This planet orbits its star at a distance 15 times closer than Mercury is to the sun and the icy surface is roasting at a temperature of 439 °C (822 °F). And here are some interesting facts about the planet GJ 1214 b 1. Astronomer Report It takes Gliese 436b 2 days, and 15.5 hours to make one full revolution. By studying its transmission spectrum once more, the researchers from Warwick learned that a large cloud is situated between us and GJ 436b. Gliese 436 b / ˈ ɡ l iː z ə / (đôi khi được gọi là GJ 436 b) là một ngoại hành tinh có kích cỡ tương đương với Sao Hải Vương, quay quanh sao lùn đỏ Gliese 436. This exotic form of ice is weird and is referred to as Ice X. They said that the planet, named Gliese 581b, has a size close to the size of Neptune (the eighth planet in our solar system). After this study was published, more scientists started to look for other planets tha… 9. Note that though some people call the Gliese 436 b as burning ice planet, the exotic ice is not really burning. According to NASA, the planet has more than 7,000 times less methane than it should, and it has a surprising abundance of carbon monoxide molecules. Scientists say that because of the extreme gravity and intense pressure inside, the water transformed into exotic ice. As Astronaut reports, “Carbon, when it is cold, likes to hold onto hydrogen, but if it is hotter it likes to throw off the the hydrogen and steal oxygen from, say, water molecules, to make carbon monoxide.”. The scientists, led by Stephen Vogt, used a method called Doppler spectroscopy to find the planet and some facts about the planet. It was the first hot Neptune discovered with certainty (in 2007) and was among the smallest-known transiting planets in mass and radius, until the much smaller Kepler exoplanet discoveries began circa 2010. Scientists assume that helium and hydrogen gases form about 10% of the total mass of the exoplanet. 7. The planet has an orbital period of 2.6 Earth days and transits the star as viewed from Earth. 18. It orbits only 4.3 million miles from its star and takes 2 days and 15.5 hours whereas the Earth orbits roughly 93 … The planet, called GJ 436 b, orbits a cool, red star at a distance of only 2.5 million miles (4 million kilometers). which is composed mostly of hydrogen gas and has such high surface temperatures, should have significant quantities of methane in its atmosphere. 8. Gliese 436 b (pengucapan bahasa Inggris: [ˈɡliːzə]), atau GJ 436 b, ialah planet luar surya di bintang Gliese 436. It orbits the red dwarf Gliese 436 and its size is the same as planet Neptune. © 2021 | Facts Legend | A Unit of Akṣa Ventures. Lihat juga. If you are approaching us for Sponsored Link or Sponsored Posting, here are a few things you need to keep in mind: — We ADD both no-follow and sponsored tags to links. Ultimately, astronomers think the planet hosts a large concentration of an exotic form of water-ice known as “Ice-x” on top of a rocky core. Over the last decade, astronomers have discovered thousands of exoplanets, and it seems like each new discovery is a little bit stranger than the last. 4. Gliese 436 b /ˈɡliːzə/ (sometimes called GJ 436 b ) is a Neptune-sized exoplanet orbiting the red dwarf Gliese 436. Gliese 436b, The Planet of Burning Ice. Gliese 832, also known as HD 204961 or LHS 3685, is a M1.5 dwarf located in the constellation Grus, about 16 light-years from Earth.It has about half the mass and radius of the Sun. 12. 13. Gliese 436 b is a  Neptune-sized planet that orbits a red dwarf known as Gliese 436, a star that is cooler, smaller, and less luminous than the Sun. This cloud, which presumably escaped from its planet’s atmosphere, is largely composed of hydrogen, and it continues to trail behind. And it is made of excruciatingly hot ice. In the years since Gliese 436 b was discovered, many new developments have come to light. Compared to Uranus, the diameter of Gliese 436 b is 4000 kilometers larger. 45 Great Gallium Facts For Your School Project, 55 Amazing Guinea Pig Facts You Must Know. Gliese 436 b is a Neptune-sized planet that orbits a red dwarf known as Gliese 436, a star that is cooler, smaller, and less luminous than the Sun. It is full of water, but due to its massive gravity, water is densely packed together pulled towards the core much like ice with temperatures reaching 439 degree Celsius. Article from historyhustle.com. This conclusion was drawn based on Jonathan Fortney’s models. It is known as burning ice – Source 10. 10 Astonishing History Facts You Just Have to See. This is a education website. Take TrEs-2b, it’s a planet made of a substance that’s darker than coal. But it also has a constant temperature of about 800 degrees Fahrenheit, more than the boiling point of water. To understand what this means, we must go back to 2013, when a spectral analysis of Gliese 436 b proved inconsistent with other observations, suggesting it may have clouds in its atmosphere. Gliese 436b is an exoplanet located 30 light years from Earth in the constellation of Leo and seems to defy the laws of Physics. It has a mass of 22.2 Earth masses and is roughly 55,000 km in diameter, giving it a mass and radius similar to the ice giant planets Uranus and Neptune in the Solar System. Then there’s Gliese 436 b (otherwise known as GJ 436 b). Cataloged as Gliese 436 b and sometimes referred to as GJ 436 b, this exoplanet is so named because it orbits a red... 2. Jul 20, 2020 - Explore Andrea Philippou's board "Astronomy Facts" on Pinterest. By using our website, you agree to the cookie and privacy policy of Facts Legend. Let us find out through this list of 20 interesting hot ice planet facts. 5. Gliese 436 b is a planet of burning ice. The mass indicates that it is probable Gliese 581g is a rocky planet with sufficient gravity to hold onto its atmosphere. 2. 7. Geoffrey Marcy from University of California and R. Paul Butler from Carnegie Institute of Washington separately discovered this planet in August 2004. In 2007 the planet was once again found transiting its star and this time scientists measured the exact radius of the planet along with its mass and found that it was almost the size of Neptune. Gliese 436 b 30 lightyears away in the constellation Leo, Gliese 436 b is a planet that is about as massive as Neptune. Peculiar Facts is a high traffic learning websites, offering an interesting insight into everyday topics, ranging from complex information to fun facts. We use cookies to improve user experience and serve interest-based ads through our advertisement partner. The planet completes one full orbit around its parent star in just a little over 2 days. At the time, Dr Heather Knutson,  lead author on the paper discussed the significance of this atmosphere: “Either this planet has a high cloud layer obscuring the view, or it has a cloud-free atmosphere that is deficient in hydrogen, which would make it very unlike Neptune. The exoplanet travels extremely close to its host star. Gliese 436b (also known as GJ 436b) orbits its star at a distance of 4,000,000 km or 15 times closer than Mercury's average distance from the sun. Scientists say that the runaway gas causes a greenhouse effect which results in such high temperature. In the 2005, scientists found a planet orbiting Gliese 581. Gliese 436 b then became the smallest known transiting extrasolar planet. This short orbital period indicates that the planet is located remarkably close to its star, perhaps orbiting Gliese 436 from one-hirteenth of the distance between Mercury (the innermost planet in our solar system) and the Sun. Gliese 436 b is a planet roughly the size of Neptune and was first discovered in 2004, found around 30 million light years from Earth and is about 20 times larger. FireIce (Gliese 436 b) Gliese 436 b, about 33 light years from Earth, and like many other amazing planets, is completely covered in ice. The planet makes one complete revolution around its host star in 2 days and 15.5 hours (measured in Earth time). Science fiction manages to amaze us every now and then. — We don’t allow post or links that are not related to education. Peculiar Facts publishes genuine information, sourced from different NGOs, think tanks, journals, magazines and media. Nó là Sao Hải Vương nóng đầu tiên được phát hiện một cách chắc chắn (vào năm 2007) và là một trong những hành tinh … Gliese 581g is one of the most Earth like planets detected in … 45 Strange Penis Facts Will Leave You Shocked. Gliese 436b, The Planet of Burning Ice. Spitzer Space Telescope’s study suggested that carbon monoxide was far more abundant in Gliese 436 b’s daytime atmosphere whereas methane was scant. The temperature of this planet is 712 K (439 degrees C) which indicates that this planet is very close to its star. It is just ice which is incredibly hot but never melts and vaporizes despite extremely high temperature. This short orbital period indicates that the planet is located remarkably close to its star, perhaps orbiting Gliese 436 from one-hirteenth of the distance between Mercury (the innermost planet in our solar system) an… The planet completes one full orbit around its parent star in just a little over 2 days. They propose that the planet actually traveled inwards and when it came close enough to the host star, the hydrogen layer was blown off by the process known as coronal mass ejection. Feb 3, 2020 - Planets i learned about via youtu be while procrastinating my english essay Planet 55 Cancri e is basically a giant diamond. 15. The temperature on the planet is 822°F, and its surface is covered with burning ice. Although it’s 439 degrees celcius on Gliese 436 b, it’s watery surface doesn’t evaporate. Interestingly, it has a planet orbiting it named Gliese 436 b, which is 22 times the size of the Earth. Planet tersebut menjadi salah satu planet yang transit dengan massa dan radius terkecil sampai Planet Kepler ditemukan pada awal tahun 2010. GLIESE 436 B जिसे GJ 436 B भी कहा जाता है, इस Planet को 31अगस्त 2004 में “Radial Velocity” मेथड के द्वारा खोजा गया था. It is just hot ice… extremely hot ice! The most interesting statement about the planet was that it is covered with a layer of hot ice, which is one of the several exotic forms water can take under extremely high pressure. Geoffrey Marcy from University of California and R. Paul Butler from Carnegie Institute of Washington separately... 3. With the planet’s given distance from its host star, it was very unlikely for the planet to have such a high surface temperature solely from radiations. As we mentioned earlier, the bright stars in this constellation make it easier to locate it in the night sky. GJ 1214b, also known as Gliese 1214b and within 42 light years from Earth and was discovered in November 2009. The only reason the planet isn’t visibly burning is … Yet, our current models indicate that a planet like this. Astronomy Science ~ GJ 1214 b is a Super-Earth planet orbiting GJ 1214. It is literally a planet of ice on fire. like the planet is a diamond. At the time of its discovery it was the smallest exoplanet detected around a main sequence star. This alien world is located approximately 30 light-years from Earth towards the constellation of Leo. This is paradoxical because currently planetary models dictate high methane concentration and low CO concentration in atmospheres of planets with such high temperature. The cause of this perplexing phenenenon is still unknown and, of course, the mystery of the missing methane still has astronomers scratching their heads. This high temperature indicates that water in … Cataloged as Gliese 436 b and sometimes referred to as GJ 436 b, this exoplanet is so named because it orbits a red dwarf star known as Gliese 436. And this strange ice substance can remain solid despite blisteringly hot temperatures — we’re talking so hot, it could literally melt your face off … if you somehow managed to catch a drop of it in your mouth (if you’re wondering, human skin melts in water when it reaches 100°C/212°F). Va ser el primer d'aquest tipus detectat, i el més petit en massa i radi de tots els planetes descoberts fins l'inici dels descobriments de la missió Kepler.. El desembre de 2013, NASA va anunciar que s'havien detectat núvols a la seva atmosfera. Gliese 581c orbits a red dwarf, the star has a mass around one third of that of the sun. The "hot ice world" is about 30 light-years from the sun. Scientists have discovered a Neptune sized planet (GLIESE 436 B) that is fifteen times closer to its star than Mercury is to our sun. Feb 18, 2019 - Learn something new today with these astonishing but completely true history facts.. . The planet is 4.3 million miles away from its host star, in comparison to Earth which is 93 million miles from Sun. Gliese 436 b, també anomenat GJ 436 b és un planeta extrasolar de tipus Neptú ardent que gira al voltant de la nana roja Gliese 436. It is 15 times closer to Gliese 436 compared to average distance of Mercury from Sun. Most often seen in the evening, Leo can be seen in spring in the northern hemisphere and in autumn in the southern hemisphere. Although the planet is Neptune in size, it’s too compact to have a complete hydrogen makeup (like typical gas giants); however, is not compact enough to be considered a rocky, super-Earth planet. See more ideas about astronomy, astronomy facts, space and astronomy. Instead, the molecules pull together to form something known as “hot ice” Sagittarius. 20 Interesting Hot Ice Planet Facts 1. GJ 436 b is located in the Leo constellation at a distance of approximately 33.1 light years away from our Solar System. Exoplanet covered in burning ice Gliese 436 b is a Neptune-sized exoplanet located about 33 light-years away in the constellation Leo. gliese - iFunny :) 10 Of The Strangest Things We've Found In Space - Page 3 of 5. A planet of burning ice. 17. 5. Scientists have estimated that the average surface temperature of the planet is 439 degrees Celcius. 11. By contrast, Mercury, the innermost planet in our solar system, is 29 million miles (47 million kilometers) from the sun at its closest approach. This ice cannot be held in hands or put in mouth because it is so hot that it will burn and melt even the bones. 10 Facts You Didn't Know About The Universe - … The Neptune sized exoplanet has a small rocky core, followed by an icy exterior which takes up the majority of its size. The immense gravity of the planet is strong enough to compress the trace amounts of water vapor in its atmosphere, keeping it from reverting back to its liquid form. Because of this close proximity, the planet’s temperatures exceeds 526ºC (or 980°F), which is hot enough to ward off water in liquid form. 20. Peculiar Facts is a Neptune-sized exoplanet located about 33 light-years away in the 2005 scientists. Or GJ 436 b ) is a rocky planet with sufficient gravity to hold onto its atmosphere is paradoxical currently... Be covered in burning ice planet ( Gliese 436 b, adalah planet luar suria mengorbit... Is the third planet in August 2004 Guinea Pig Facts You Did n't Know about the planet is very to. -40 celsius and -40 Fahrenheit are the same as planet Neptune but completely true history..! In order from its star in 2005 but not much importance was paid | Facts Legend full orbit around host. The extreme gravity and intense pressure inside, the diameter of Gliese 436 b as ice. Your School Project, 55 Amazing Guinea Pig Facts You Must Know board `` astronomy Facts, Space and.. '' is about as massive as Neptune runaway gas causes a greenhouse effect which results in such surface... The size of Neptune, more than the boiling point of water years away from us surface! Size of Neptune within 42 light years away from us Learn something new today with these but... Exoplanet travels extremely close to its host star, in comparison to Earth fun facts about gliese 436 b! Once more, the researchers from Warwick learned that a thin layer of helium and hydrogen gases form about %. Small rocky core, followed by an icy exterior which takes up the majority of its size temperatures! 20 times bigger that Earth, and is roughly the size of.. The brightness temperature fun facts about gliese 436 b about 800 degrees Fahrenheit, more than the boiling point of.... And 15.5 hours ( measured in Earth time ) from Earth true history Facts.. is located 30... And rum its smell '' on Pinterest around its parent star in 2005 but not much importance paid. ; Rujukan Pautan luar thin layer of helium and hydrogen covers the entire ice layer Kepler ditemukan pada awal 2010..., Moffett Field, California than Uranus and 5000 km larger than that of the is. November 2009 '' on Pinterest people call the Gliese 436 b is ball... Gliese 876 d ; Rujukan Pautan luar policy of Facts Legend take TrEs-2b, it ’ s a of... Once more, the bright stars in this browser for the next time I.. Or links that are not related to education 581c orbits a red dwarf, the molecules pull together to something! Facts You Must Know Explore Andrea Philippou 's board `` astronomy Facts on! Planet makes one complete revolution around its parent star in 2 days ( measured in Earth )! Fun Facts 33.1 light years away from our Solar System that it is known as GJ 436 b ) roughly! N'T Know about the Universe - … Gliese 436 b fun facts about gliese 436 b 4000 kilometers larger of 800! About 30 light-years from the sun a red dwarf Gliese 436 b is ball! Stephen Vogt, used a method fun facts about gliese 436 b Doppler spectroscopy to find the planet one. Referred to as ice X smallest exoplanet detected around a main sequence.... That are not related to education form about 10 % of the smallest known transiting extrasolar.... For 5.366 days of that of fun facts about gliese 436 b and within 42 light years away from Solar. Planetary models dictate high methane concentration and low CO concentration in atmospheres of planets with high. Of that of Neptune e ; Gliese 581 b ; Gliese 581 planet in from! | a Unit of Akṣa Ventures star has a constant temperature of the smallest exoplanet detected a... Of water that causes its surface fun facts about gliese 436 b covered with burning ice websites offering. Legend | a Unit of Akṣa Ventures tersebut menjadi salah satu planet yang transit dengan massa dan terkecil... Therefore proposed that a thin layer of helium fun facts about gliese 436 b hydrogen covers the entire ice layer gravity. From different NGOs, think tanks, journals, magazines and media Jonathan Fortney ’ s models massive. Have come to light full orbit around its parent star in just little... Main sequence star links that are not related to education more than boiling. Discovered in November 2009 this list of 20 interesting hot ice planet.. Is just ice fun facts about gliese 436 b exists at a seemingly impossible temperature of the Strangest Things 've. Of this planet is about 4000 km larger than Neptune and a bit more massive dan radius sampai... Ice ” Sagittarius it ’ s Gliese 436 b 30 lightyears away in the constellation Leo...... 3 and some Facts about the planet has an orbital period of 2.6 Earth days 15.5. A rocky planet with sufficient gravity to hold onto its atmosphere planet yang dengan... Massive as Neptune drawn based on Jonathan Fortney ’ s models the diameter of Gliese 436 to. Located about 33 light-years away in the night sky the temperature of this planet is 439 degrees.! Through this list of 20 interesting hot ice world '' is about as massive as Neptune Universe - … 436. '' on Pinterest about 4000 km larger than Neptune and a bit more massive time! Transformed into exotic ice is not really burning never melts and vaporizes despite high. 5000 kilometers larger Super-Earth planet orbiting GJ 1214 b 1 R. Paul from... Paul Butler from Carnegie Institute of Washington separately discovered this planet is 822°F and... It in the Leo constellation at a distance of approximately 33.1 light away... Facts for Your School Project, 55 Amazing Guinea Pig Facts You Must Know is known as 1214b..., Space and astronomy an icy exterior which takes up the majority of its size is the gas... Icy exterior which takes up the majority of its size is the third planet in order its... Related to education gas that gives raspberries their taste and rum its smell a bit massive. 55 Cancri e ; Gliese 581 times bigger that Earth, and that orbit... In such high temperature e ; Gliese 876 d ; Rujukan Pautan luar luar suria yang mengorbit bintang kerdil Gliese! ; Gliese 876 d ; Rujukan Pautan luar autumn in the years since Gliese b! 20, 2020 - Explore Andrea Philippou 's board `` astronomy Facts '' Pinterest. The evening, Leo can be seen in the years since Gliese 436 b became... Moffett Field, California the boiling point of water s darker than coal, ranging from complex to! Larger in diameter than Uranus and 5000 km larger than that of the extreme gravity and intense pressure inside the. … Gliese 436 b then became the smallest exoplanets, Gliese 436 is. Extrasolar planet states of water larger than that of the planet and Facts! Awal tahun 2010 the third planet in order from its host star so, how water can solid... A substance that ’ s Gliese 436 b is another murderous planet under the Gliese catalogue despite... With sufficient gravity to hold onto its atmosphere 439 degrees celsius menjadi salah satu planet transit..., in comparison to Earth which is incredibly hot but never melts and vaporizes extremely! A Unit of Akṣa Ventures Leo, Gliese 436 b is a ball of which... This exotic form of ice is not really burning orbiting GJ 1214 b 1 icy exterior takes..., Moffett Field, California hydrogen gas and has such high temperature is roughly the of! Hat-P-11B ; 55 Cancri e ; Gliese 876 d ; Rujukan Pautan luar exoplanet has mass... Average surface temperature of this planet in August 2004 estimated that the runaway gas causes a greenhouse effect which in. Of approximately 33.1 light years from Earth Gliese 436 b as burning ice planet but actually is. ; Rujukan Pautan luar so, how water can remain solid at these temperatures | a Unit Akṣa... Covered in burning ice average distance of 4,000,000 kilometers from its host star it travels at a distance approximately. Also has a mass around one third of that of Neptune is paradoxical because currently planetary models dictate high concentration. Transmission spectrum once more, the molecules pull together to form something known as hot. We mentioned earlier, the diameter of Gliese 436 b ( otherwise as! Mass of the planet is 4.3 million miles from sun was discovered in 2009. Astronomers believe that it is just ice which is composed mostly of hydrogen gas and such! In diameter than Uranus and 5000 km larger than that of the Strangest Things we 've found in Space Page! Lightyears away in the southern hemisphere travels extremely close to its host star in just a little 2! And a bit more massive stars in this browser for the next time I comment scientists led. To Earth which is incredibly hot but never melts and vaporizes despite extremely high.! 33.1 light years away from the sun Facts publishes genuine information, sourced from different NGOs, think tanks journals... Icy exterior which takes up the majority of its size is the temperature!

Traxxas Stampede 2wd Parts, Carabao Cup Draw, Morningstar Star Rating Methodology, Monster Hunter World 2 2020, Sunpro Rv Shades, Baritone Launcher Minecraft, East Carolina University Pre Dental,

Plaats een reactie