Our Spitzer Space Telescope has revealed the first known system of seven Earth-size planets around a single star. Three of these planets are firmly located in an area called the habitable zone, where liquid water is most likely to exist on a rocky planet.
This exoplanet system is called TRAPPIST-1, named for The Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile. In May 2016, researchers using TRAPPIST announced they had discovered three planets in the system.
Assisted by several ground-based telescopes, Spitzer confirmed the existence of two of these planets and discovered five additional ones, increasing the number of known planets in the system to seven.
This is the FIRST time three terrestrial planets have been found in the habitable zone of a star, and this is the FIRST time we have been able to measure both the masses and the radius for habitable zone Earth-sized planets.
All of these seven planets could have liquid water, key to life as we know it, under the right atmospheric conditions, but the chances are highest with the three in the habitable zone.
At about 40 light-years (235 trillion miles) from Earth, the system of planets is relatively close to us, in the constellation Aquarius. Because they are located outside of our solar system, these planets are scientifically known as exoplanets. To clarify, exoplanets are planets outside our solar system that orbit a sun-like star.
In this animation, you can see the planets orbiting the star, with the green area representing the famous habitable zone, defined as the range of distance to the star for which an Earth-like planet is the most likely to harbor abundant liquid water on its surface. Planets e, f and g fall in the habitable zone of the star.
Using Spitzer data, the team precisely measured the sizes of the seven planets and developed first estimates of the masses of six of them. The mass of the seventh and farthest exoplanet has not yet been estimated.
For comparison…if our sun was the size of a basketball, the TRAPPIST-1 star would be the size of a golf ball.
Based on their densities, all of the TRAPPIST-1 planets are likely to be rocky. Further observations will not only help determine whether they are rich in water, but also possibly reveal whether any could have liquid water on their surfaces.
The sun at the center of this system is classified as an ultra-cool dwarf and is so cool that liquid water could survive on planets orbiting very close to it, closer than is possible on planets in our solar system. All seven of the TRAPPIST-1 planetary orbits are closer to their host star than Mercury is to our sun.
The planets also are very close to each other. How close? Well, if a person was standing on one of the planet’s surface, they could gaze up and potentially see geological features or clouds of neighboring worlds, which would sometimes appear larger than the moon in Earth’s sky.
The planets may also be tidally-locked to their star, which means the same side of the planet is always facing the star, therefore each side is either perpetual day or night. This could mean they have weather patterns totally unlike those on Earth, such as strong wind blowing from the day side to the night side, and extreme temperature changes.
Because most TRAPPIST-1 planets are likely to be rocky, and they are very close to one another, scientists view the Galilean moons of Jupiter – lo, Europa, Callisto, Ganymede – as good comparisons in our solar system. All of these moons are also tidally locked to Jupiter. The TRAPPIST-1 star is only slightly wider than Jupiter, yet much warmer.
How Did the Spitzer Space Telescope Detect this System?
Spitzer, an infrared telescope that trails Earth as it orbits the sun, was well-suited for studying TRAPPIST-1 because the star glows brightest in infrared light, whose wavelengths are longer than the eye can see. Spitzer is uniquely positioned in its orbit to observe enough crossing (aka transits) of the planets in front of the host star to reveal the complex architecture of the system.
Every time a planet passes by, or transits, a star, it blocks out some light. Spitzer measured the dips in light and based on how big the dip, you can determine the size of the planet. The timing of the transits tells you how long it takes for the planet to orbit the star.
The TRAPPIST-1 system provides one of the best opportunities in the next decade to study the atmospheres around Earth-size planets. Spitzer, Hubble and Kepler will help astronomers plan for follow-up studies using our upcoming James Webb Space Telescope, launching in 2018. With much greater sensitivity, Webb will be able to detect the chemical fingerprints of water, methane, oxygen, ozone and other components of a planet’s atmosphere.
At 40 light-years away, humans won’t be visiting this system in person anytime soon…that said…this poster can help us imagine what it would be like:
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Mother Sara and the Baby, Mary Cassatt
Medium: pastel on paper
“To go wrong in one’s own way is better than to go right in someone else’s.”
— Fyodor Dostoyevsky, Crime and Punishment (via books-n-quotes)
Remembering Alfred Hitchcock 🌹on his Birthday 🎁
Princess Sophie of Prussia and Victoria (‘Vicky’), Crown Princess of Prussia, 1874
“Childhood ought to be such a happy time, it never returns. I remember what a coward I was as a child over all and everything except the water. I think I had a fairly good nerve when I grew up because my Papa was so kind and patient, and I felt that when he was near nothing could happen to me. If he had scolded and shaken or forced me, I should have been nervous and terrified of him as well. Papa always said he could not bear to think of his childhood, he had been so unhappy and miserable, and had many a time wished himself out of this world.
I always think we grown-up people ought to be so careful how we exact obedience from our children. Obedience that is not cheerful or willing only ruins the character. All that nonsense of ‘breaking the will’ is now recognised as making children vicious and false and sly. Training a child’s will so that it may trust willingly to the guidance of its elders, and believe in their protection, has obtained far happier results than enforcing a dogged obedience, as the child is not convinced that it is wrong but only dreads the consequences of displeasing its elders. But all this we only realise when we are older and have seen something of the world and of character and of childhood.
For all these reasons I am so much for the 'Kinder Garten’, and against the dreadful old system of 'infant schools’, where poor little things were chiefly instructed to sit still and obey like little machines or tiny recruits, which is so utterly the reverse of a child’s nature, that wants constant movement and change and liberty, as well as love and kindness, to grow like a young plant in the sunshine.”
- Vicky
http://www.personal-quotes.com
"In order to move on, you must understand how you felt, and why you felt it." Mitch Albom
Mindfulness has been proven to have many personal and professional benefits, including discipline, tolerance, calmness, and mental clarity. In a professional sense, mindful thinking and practice has been proven to lead to better productivity and workplace satisfaction. Our Mindfulness program, presented in partnership with the Factor-Inwentash Faculty of Social Work, provides a secularized approach to the traditional Buddhist practice. Designed in such a way that it can be applied to many different areas of professional and personal life, our courses are taught by instructors who have a wide range and depth of experience in a variety of disciplines.
The professional Tai Chi Swords on: http://www.icnbuys.com/tai-chi-swords.
A long time ago before I studied medicine, before even biomedicine, I used to volunteer in hospital. It was scary at first; most teenagers are out there having a life, meanwhile you’re wandering around on wards. At first, I was worried I would get in the way. I mean, important stuff happens in hospital, right? There are lots of busy doctors and nurses rushing around and doing important things. Things that actually matter to patient care. I didn’t want to get in their way. I was even worried I’d trip up an important cable or get in the way of a ward round or something! As volunteers we could do all sorts of little jobs that other people weren’t being paid to do. We would go around with the library trolley or shop trolley. Or help re-stock gloves, hand gel and things like that on the wards. We directed lost visitors around the site. We helped with lunches. If you were unlucky, you’d be asked to do something less exciting like stuff envelopes. But sometimes, after a tiring week of revision, it was actually a nice break. I challenged myself to be as efficient at the repetitive tasks as I could be; they usually ran out of tasks sooner than expected! Pretty often, we got to chat with patients, which I really enjoyed. I got to know a lot of the ward sisters, and all the staff were really welcoming and pleasant. I had little interaction with the doctors, though they were always polite and friendly when I was selling the poor juniors snacks from the shop trolley, which must have been a lifesaver in itself! I didn’t interact with the medical students. It never occurred to me to ask them questions about medicine; the mere thought of approaching anybody who was somebody was terrifying. I didn’t think what I did was meaningless, but I did feel it wasn’t that special. It was just all I could do at the time. And that was enough for me. When I was a student, I still felt like an outsider in hospital. It takes all your guts to wander into a strange ward or an operating theatre armed with nothing more than your ID badge and a clinical handbook of medicine, and say ‘I’m… I’m the medical student?’ when they ask you who you are. To which they usually reply ‘Eh? I thought they were coming next week…’. I can’t count the number of times I uttered the words ‘I’m just a medical student’. Because I couldn’t diagnose or treat or prescribe, it was easy to sometimes feel that whilst we were learning, we weren’t really doing anything to help. I remember our doctor tutors frequently telling us ‘you’re not just a medical student.’. It was pretty nice that they cared, but it didn’t stop us apologising constantly. It’s not that easy to change how you feel, after all. At some point, I resolved to stop using those words. And if I remember correctly, I mostly succeeded. But I only really gave them up when I had to: when those things actually became my job. The further along we got, the more we wanted to learn how to do everything, and the more we devoted ourselves to mopping up any jobs we could help with. I loved to devote time to talking to patients; I couldn’t ‘clerk’ as a student without being drawn into long rambling conversations. I didn’t feel as invisible as when I was a volunteer, but you feel so constrained by what you can’t do that it’s still easy to overlook what you can. Especially when you first start on the wards. But now, as a doctor, I can really appreciate that what I did back then wasn’t really insignificant at all. Not by a long shot. Because now, more than ever, I have to rely on every other person to do all the things I can’t do. Back when I was doing these things, I thought they weren’t that important because anyone can do them. Now I realise that although anyone can do them, most people in hospital can’t. Because there are so many other things that need doing. So many. When there aren’t gloves anywhere, and there is no hand gel in any of the dispensers, it makes doing my job safely that little bit harder. When the proformas aren’t in place or cupboards aren’t stocked or the ward is a mess, life is a little harder. When the OR isn’t cleaned, it takes longer for the next operation to happen. When my patients are lonely, it makes their stay in hospital more painful than it should be. When there’s nobody there who can do bloods or a cannula or even just fill out some blood forms, we can become swamped in lots of little tasks. Add all these little things up, and you’ve got some pretty stressed doctors and nurses! To anybody out there who feels insignificant because they’re ‘just’ helping with the little tasks; thank you. We couldn’t do it without you.