The best way to learn about anything is to start with the basics, and one of the largest basics is vocabulary. I hope you enjoy some science vocab!!
Bar - “A unit of measure of atmospheric pressure. One bar is equal to 0.987 atmospheres, 1.02 kg/cm2, 100 kilopascal, and 14.5 lbs/square inch.”
Barycenter - “The center of mass of a system of bodies, such as the solar system. When a comet, for example, is well outside the orbit of Neptune (the farthest major planet), it sees the sun and major planets essentially as a single object of summed mass, and the center of this mass (called the barycenter of the solar system) is offset somewhat from the sun; “original” and “future” orbits of long-period comets are computed for this barycenter, while perturbed, osculating orbits of currently-observed objects in the inner solar system are computed for heliocentric orbits.”
Barycentric Dynamical Time (TDB) - “Differing from TDT only via periodic variations, TDB is used in ephemerides and equations of motion that refer to the barycenter of the solar system.”
Baryon - “A massive elementary particle made up of three quarks. Neutrons and protons are baryons.”
Besselian year - “A quantity introduced by F. W. Bessel in the nineteenth century that has been used into the twentieth century. Bessel introduced a system whereby it would be convenient to identify any instant of time by giving the year and the decimal fraction of the year to a few places, but the starting time of the year was not convenient for dynamical studies that utilize Julian dates (see definition for Julian date), differing by 0.5 day, and the Besselian year varies slowly. The recent change to Julian year usage in dynamical astronomy (and the J2000.0 equinox) took effect in solar-system ephemerides of the Minor Planet Center and Central Bureau for Astronomical Telegrams on Jan. 1, 1992. (See Julian year.)”
Big Bang - “The theory that suggests that the universe was formed from a single point in space during a cataclysmic explosion about 13.7 billion years ago. This is the current accepted theory for the origin of the universe and is supported by measurements of background radiation and the observed expansion of space.”
Binary - “A system of two stars that revolve around a common center of gravity.”
Blackbody - “An object with a constant temperature that absorbs all radiation that hits it.”
Black Hole - “The collapsed core of a massive star. Stars that are very massive will collapse under their own gravity when their fuel is exhausted. The collapse continues until all matter is crushed out of existence into what is known as a singularity. The gravitational pull is so strong that not even light can escape.”
Blueshift - “A shift in the lines of an object’s spectrum toward the blue end. Blueshift indicates that an object is moving toward the observer. The larger the blueshift, the faster the object is moving.”
Bolide - “A term used to describe an exceptionally bright meteor. Bolides typically will produce a sonic boom.”
Europe is looking to open a new frontier in the ever more urgent quest for new natural resources – the pristine icy wastes of Greenland.
Oil and gas have been the focus of exploitation so far – but the EU sees just as much potential in a massive opening up of mining operations across the world’s biggest island, according to Antonio Tajani, the European commission’s vice-president and one of the most powerful politicians in the union. He called the move “raw material diplomacy”.
Latest satellite data reveal that 97% of the surface of the Greenland ice sheet underwent surface melting over four exceptionally warm days in July, indicating natural resources will become more available for extraction in the coming decades.
The potential gold rush is being welcomed by some in Greenland, but has raised fears of environmental damage, pollution and despoliation across the Arctic that could destroy one of the world’s last wildernesses.
Tajani said: “Greenland is hugely important in terms of natural resources, it has vast opportunities. We are currently working very hard with the prime minister of Greenland on this – we are working on our own agreement with Greenland on raw materials.”
He said: “This is raw material diplomacy. We have allies working on this worldwide.”
Greenland’s government is keen to exploit the island’s natural wealth in order to alleviate some of the serious poverty and social problems that blight the indigenous population.
Henrik Stendal, of the Greenland government’s mineral extraction department, told the Guardian: “The government would like to have another source of income – currently there is just fishing, and a little from tourism, so this is a big opportunity for us. These explorations can be done sensitively, we believe.”
“I’m glad to be here right now, poking at my threshold. I want to get more comfortable being uncomfortable. I want to get more confident being uncertain. I don’t want to shrink back just because something isn’t easy. I want to push back, and make more room in the area between I can’t and I can. Maybe that spot is called I will.”—Kristin Armstrong (via short-shortsandshoelaces)
“He’d make very interesting noises. His laugh was explosive and uninhibited. It was the kind of laugh that made you feel good for making him laugh. His sneezes were booming. And sometimes he’d talk to animals in their native tongue. The times we’d see dolphins, he’d greet them in a reasonable approximation of dolphin speak. They’d often answer him. I have no idea what was said. But my favorite sound of his was the sound he’d make upon discovering something interesting and new, some idea or possibility that impressed him or opened up a fresh way of looking at things. It was a kind of “aaah.” One of my proudest moments: We were watching my first Star Trek episode, “Attached,” and within minutes he’d made the sound, turning to me with a beaming smile and saying, “That’s really good.” And this continued for the entire show. The completeness of how much he loved what I’d done, that genuine sense of enjoyment stays with me, a sense of respect and approval I treasure like nothing else.”—Nick Sagan, talking about his father Carl Sagan (via astrotastic)
if everything came from the big bang, and the big bang before it exploded was so dense, then why didn't it collapse into a huge black hole?
This seems to be something that comes up quite a bit, but it is a good question, none the less.
I’m going to copy & paste this answer because what I typed up was three times longer than this simple one-paragraph explanation:
“The short answer is that the Big Bang gets away with it because it is expanding rapidly near the beginning and the rate of expansion is slowing down. Space can be flat even when spacetime is not. Spacetime’s curvature can come from the temporal parts of the spacetime metric which measures the deceleration of the expansion of the universe. So the total curvature of spacetime is related to the density of matter, but there is a contribution to curvature from the expansion as well as from any curvature of space. The Schwarzschild solution of the gravitational equations is static and demonstrates the limits placed on a static spherical body before it must collapse to a black hole. The Schwarzschild limit does not apply to rapidly expanding matter.”
When you have the time to read further, you can look into Is the Big Bang a Black Hole? which explains, in detail, the differences between the Big Bang and black holes. I hope this helped you out some!
Do you think you can do the cosmology post again, only this time focused on astrophysics? Although I'm still in high school, it's my dream to teach physics/astronomy/astrophysics in high school/college.
Of course! [I will be posting this because I’m sure someone else will find it helpful as well.]
As in the previous ask, PhysicsToday provides a clear, and basic explanation of what different areas are available to those interested in Astronomy & Astrophysics oriented careers. [As well as why Astronomy and Astrophysics are usually paired together.]:
“The two terms are generally linked when naming scientific journals covering the subject and graduate science departments because most professional astronomers have graduate degrees in physics. As a result we include astronomy jobs and astrophysics jobs in one category and have a separate category for space physics jobs. The discovery that the universe is expanding was an astronomical advance, that piqued interest in astronomy and astrophysics careers worldwide. Thetheoretical equation relating the speed of a star with its redshift is an achievement atributed to career astrophysicists. Likewise, radio astronomy was responsible for the discovery of cosmic microwave background radiation (CMBR), but astrophysics showed the connection between CMBR and the Big Bang. So the overlap of careers in astronomy and astrophysics is quite prevalent. In addition to all of the electromagnetic spectrum, career astronomers now use neutrinos from the Sun and supernovae with detectors placed underground. There are also interferometers that respond to gravitational radiation instead of light, with arms that are 4 km long, to detect the gravity waves of general relativity.
There are a great many amateur astronomers and societies. A common activity is called star hopping, which involves locating faint stars, galaxies, and other celestial objects with the help of star charts and bright stars. Amateur astronomers often contribute to the lifework of career astronomers by monitoring the changes in brightness of variable stars, tracking asteroids, discovering comets, and observing occultations.
Dark matter and dark energy are hypothetical concepts whose existence is indicated by recent discoveries. Matters of current interest to career astrophysicists are the dynamics of stellar evolution, galaxy formation, black holes, and the origin of cosmic rays. Until very recently, the largest structures were thought to be superclusters of galaxies, which are bigger than clusters of galaxies. Now, there are voids, filaments and walls of galaxies, and gaseous structures 400,000 light years across. With all these new and exciting discoveries, its no wonder we have an abundance of astronomy jobs and astrophysics jobs listed on our boards.”
And from Ask An Astrophysicist, below is a huge compilation of educational links you can click through, and read in your own due time, concerning what to expect as a student, as well as after graduation, and everything in between.
im thinking about studying cosmology at the mary queen university of london (im colombian so i dont know a lot about it) do you think its a good idea? or can you recomend me any other university?, also, i want to know how's the career of a cosmologist? what do you have to study first or whatever, good and bad things about it and what would i do after finishing college, like works where i could apply and that, thank you and sorry if a bothered you
Hello dear anon!
Well, well, this is quite the ask. Please don’t apologize, you’re not a bother at all!
Firstly, I think studying cosmology, in general, is a brilliant idea! As for the bit about specifically attending Mary Queen University of London, I’m not in the UK, [nor have I researched this school enough] so I really can’t tell you if this would be a good school for you or not. From what I’ve done, research wise, it seems like it might actually be a pretty lovely school, especially if you’re planning on studying sciences focusing on outer-space. [Again, I haven’t researched too much into it, so I’d suggest you personally getting in contact with some possible alumni, and talking to them about their studies, how they felt about it, and the school in general.]
If you look here, on their main page for studies in Cosmology, they provide you with a plethera of links with what courses to expect, what projects to expect, and even projects to do before you attend, as you can read & click through below:
“Our primary research interests span a wide range of important theoretical topics in modern cosmology.
If you message me off-anon, we can privately discuss other Universities if you’d like to give me an idea of what countries you would be willing to attend University in so we can narrow it down a bit.
I would also like to clear up the ever-present myth that I am a cosmologist, astronomer, or scientist in the professional sense, I’m merely an amateur science advocate with a strong passion for outer-space. So, seeing as I myself am not a cosmologist, I can only tell you so much about what to expect, but I can definitely help send you in the right direction for some further personal research on your end.
Below PhysicsToday explains what is necessary to know if you wish to pursue cosmology, and what to expect in a career:
“Cosmology is a branch of astronomy and careers in this field are mostly made at universities and colleges. You can’t claim to have a job in cosmology if you don’t know about the Big Bang model of the universe, elementary particle physics, unified field theories, nucleosynthesis, the cosmological constant, Friedman equations, plasma physics, cosmic microwave background radiation, and the Wyle curvature hypothesis. A research job in cosmology means investigating galaxies, clusters, superclusters, and quasars.
… A career in cosmology, however, does not necessarily involve cosmogony. Cosmogony is the study of the origin of the solar system and falls into the job description of an astronomer. The cosmological career path began with Einstein’s general theory of relativity and better astronomical observations of extremely distant objects. A cosmologist should also know about string theory and phenomenology in science. A career in string theory is precarious, but the theory itself combines quantum mechanics and gravity. Superstring theory incorporates fermions and supersymmetry and leads to string and p-brane (membrane, M-theory) cosmology.”
To answer your questions about good & bad things about it, and what you do after university, like where you’d work, is difficult due to these things all being huge variables depending on what you focus on specifically, as well as where you attend University, and/or plan to live for the next 5-10 years.
Below, if you wish to further explore, is a list of some links for you to do some research and learning on what you will need to be knowledgeable in for a career in Cosmology:
Universe 101 - A great place to learn the beginning basics of Cosmology.
As previously I said, if you’d like, we can further discuss other University options, as well as the specifics of what you’ll need to know/study, and what to expect for a career by messaging me off-anon privately. I hope this helps you a bit, and I wish best of luck with your future endeavours if we don’t speak again!
I finally made a page of a list of scientific terms & definitions that I compiled from multiple sources. [Many of the terms and definitions concern astronomical and cosmological branches of science.] Over the next few weeks I will be making posts for each letter grouping, starting today with the A group. The best way to learn about anything is to start with the basics, and one of the largest basics is vocabulary, so I hope you enjoy some science vocab!!
Absolute Magnitude - “A scale for measuring the actual brightness of a celestial object without accounting for the distance of the object. Absolute magnitude measures how bright an object would appear if it were exactly 10 parsecs (about 33 light-years) away from Earth. On this scale, the Sun has an absolute magnitude of +4.8 while it has an apparent magnitude of -26.7 because it is so close.”
Absolute Zero - “The temperature at which the motion of all atoms and molecules stops and no heat is given off. Absolute zero is reached at 0 degrees Kelvin or -273.16 degrees Celsius.”
Absorption Line - “A more or less narrow range of wavelengths in aspectrum that is darker than neighboring wavelengths. Absorption lines are seen in stars.”
Ablation - “A process by where the atmosphere melts away and removes the surface material of an incoming meteorite.”
Accretion - “The process by where dust and gas accumulated into larger bodies such as stars and planets.”
Accretion Disk - “A disk of gas that accumulates around a center of gravitational attraction, such as a white dwarf, neutron star, or black hole. As the gas spirals in, it becomes hot and emits light or even X-radiation.”
Albedo - “The reflective property of a non-luminous object. A perfect mirror would have an albedo of 100% while a black hole would have an albedo of 0%.”
Albedo Feature - “A dark or light marking on the surface of an object that may or may not be a geological or topographical feature.”
Altitude - “The angular distance of an object above the horizon.”
Angles - “Are measured in degrees or arcminutes (denoted by a single quote) or arcseconds (denoted by a double quote) or radians. 1 radian = 180/pi = 57.2958 degrees, 1 degree = 1o = 60 arcminutes = 60’ = 3600 arcseconds = 3600”.”
Antimatter - “Matter consisting of particles with charges opposite that of ordinary matter. In antimatter, protons have a negative charge while electrons have a positive charge.”
Antipodal Point - “A point that is on the direct opposite side of a planet.”
Apastron - “The point of greatest separation of two stars, such as in a binary star system.”
Aperture - “The size of the opening through which light passes in an optical instrument such as a camera or telescope. A higher number represents a smaller opening while a lower number represents a larger opening.”
Aphelion - “The point in the orbit of a planet or other celestial body where it is farthest from the Sun.”
Apogee - “The point in the orbit of the Moon or other satellite where it is farthest from the Earth.”
Apparent Magnitude - “The apparent brightness of an object in the sky as it appears to an observer on Earth. Bright objects have a low apparent magnitude while dim objects will have a higher apparent magnitude.”
Arc minutes - “There are 60 minutes (denoted as 60’) of arc in 1 degree. In the sky, with an unobstructed horizon (as on the ocean), one can see about 180 degrees of sky at once, and there are 90 degrees from the true horizon to the zenith. The full moon is about 30’ (30 arc minutes) across, or half a degree. There are 60 seconds (denoted 60”) of arc in one minute of arc.”
Asteroid - “A small planetary body in orbit around the Sun, larger than a meteoroid but smaller than a planet. Most asteroids can be found in a belt between the orbits of Mars and Jupiter. The orbits of some asteroids take them close to the Sun, which also takes them across the paths of the planets.”
Astrochemistry - “The branch of science that explores the chemical interactions between dust and gas interspersed between the stars.”
Astronomical Unit (AU) - “A unit of measure equal to the average distance between the Earth and the Sun, approximately 93 million miles.”
Astronomy - “The branch of science that deals with celestial objects, space, and the physical universe as a whole.”
Astrometry - “The careful, precise measurement of astronomical objects, usually made with respect to standard catalogues of star positions. For comet orbit computations, astrometry good to 1” or 2” (1 or 2 arc seconds), or better, is the standard nowadays.”
Atmosphere - “A layer of gases surrounding a planet, moon, or star. The Earth’s atmosphere is 120 miles thick and is composed mainly of nitrogen, oxygen, carbon dioxide, and a few other trace gases.”
Aurora - “A glow in a planet’s ionosphere caused by the interaction between the planet’s magnetic field and charged particles from the Sun. This phenomenon is known as the Aurora Borealis in the Earth’s northern hemisphere and the Aurora Australis in the Earth’s Southern Hemisphere.”
Aurora Australis - “Also known as the southern lights, this is an atmospheric phenomenon that displays a diffuse glow in the sky in the southern hemisphere. It is caused by charged particles from the Sun as they interact with the Earth’s magnetic field. Known as the Aurora Borealis in the northern hemisphere.”
Aurora Borealis - “Also known as the northern lights, this is an atmospheric phenomenon that displays a diffuse glow in the sky in the northern hemisphere. It is caused by charged particles from the Sun as they interact with the Earth’s magnetic field. Known as the Aurora Australis in the southern hemisphere.”
Axis - “Also known as the poles, this is an imaginary line through the center of rotation of an object.”
Azimuth - “The angular distance of an object around or parallel to the horizon from a predefined zero point.”
I have a friend always claiming her 'subconscious' is telling her what her body needs to eat based on her appetite cravings; is there any validation for this?
Well, maybe if she’s finely in tune with her body, and knows exactly what she needs due to her cravings, it would be possible. Take the chart below for example; these types of tables are very popular amongst nutritionists and health-fanatics alike. It’s a table of what you feel you’re craving, ie. sweets, salty foods, fatty foods, nothing, etc. and what that means your body really technically wants/needs, ie. certain proteins, carbon, etc. So, if she’s saying because she’s having salty-food cravings she really needs fish, or since she’s craving sweets she really needs some fresh vegetables, then she’s probably right, and it’s great she’s that knowledgeable about her own dietary and bodily needs.
She could also just be bluffing, though, as many of us do, to seem more knowledgeable on health topics than she really is. As for it being her ‘subconscious’ that’s letting her know, it might be partially true if she understands the body and mind and how they intermingle [anatomy/psychology] very well, but you can’t just directly ‘talk to your subconcious’ nor have it ‘tell you’ something. That being said, you can pay attention to your mind’s thought patterns and how they’re associated with your bodily needs, and make educated conclusions on what she needs to consume, which again, is totally possible if she’s very knowledgeable on all these different subjects.
Most people who claim their ‘subconscious’ tells them what they do and do not need [for their body, mind, or what ever else] are also usually very ‘spiritual’ people in the sense of trying to connect their full consciousness to their subconscious through new age religion[s], spiritual belief[s], certain types of meditation, etc. and are usually easily swayed by psuedo-sciences. If she seems to be the latter, I would say it’s most likely bs, unless, like I said, she’s educated and well read up on all of these subjects. [We all have those friends, though, that bullshit about such things, if it is merely bs, just ignore it. Sounds like she’s just trying to get recognition for something she may not know fully about.]
[This specific chart isn’t necessarily spot on in some areas, and are more ‘guidelines and suggestions’ than ‘You better eat veggies instead of chocolate’ etc.]
My sister just came upstairs and looked at me with really really wide eyes and shouted she actually shouted “NOTHING EVER REALLY TOUCHES ANYTHING! QUANTUM PHYSICS! HOLY SHIT!” and then ran back downstairs
that was so weird I’m a little bit scared
Okay so the whole thing is that atoms repel each other when they’re close together. But that’s “close together” on an atomic level, so like when you touch the surface of a table with your fingertip you can’t perceive distance between them.
And you feel the tabletop because the atoms of the table repel the atoms of your finger, and vice versa, and your body’s tuned to perceive that force.
So the electrons of the finger atoms aren’t actually knocking into the electrons of the tabletop atoms, they’re just repelling each other from a distance, kind of like how magnets do.
Things are really weird at the atomic level, though, because we’ve adapted to perceive everything at the human-size level. Electrons aren’t little marbles, they’re more like little clouds of energy.
So to say “things don’t REALLY touch” because they are actually just repelling at an atomic level is TOTALLY WRONG!! BECAUSE
repelling at an atomic level
is what touching IS
Also all touching atoms hold a tiny bond that ties them together. Like all the atoms in wall are stuck to each other because they’re pushed so close together that they’re sharing electrons and junk and that makes them touch. Similarly like when you put your hand on a table or your phone or wallet it actually makes a very weak atomic bond to the table, but it’s super weak because at the atomic level neither your hand or the table are perfectly smooth and it’s just a few random bumps touching a few random bumps and nothing is ever really flush EXCEPT FOR FUCKING GEKKO FEET.
Gekko feet have thousands and thousands of tiny hairs that are like as tiny as biologically possible and the little hairs are designed to totally fill in all the cracks in a surface that might look flat at a glance. So when you put your hand on a table you’re probably making 0.1% contact with the table but a gekko is probably making about 90% contact with the table.
That’s how they’re able to climb walls!
Their feet are like quantum locked to the wall and it’s like their feet are a part of the wall. They are able to easily unlock by just pulling their feet up because it only locks at a certain direction (when being pulled down with gravity, not when being pulled upwards by muscles) and when they walk down a wall they actually twist their feet around 180 degrees so that their feet are still facing ‘up’ as if they were climbing up even though their body is headed down.
The following is an excerpt from an article published in Harvard Magazine on July 26, 2012:
A team of Harvard scientists led by Weld professor of atmospheric chemistry James G. Anderson announced today the discovery of serious and wholly unexpected ozone loss over the United States in summer. The finding, published in advance online on July 26 at Science’s Science Express website, is startling because the complex atmospheric chemistry that destroys ozone has previously been thought to occur only at very cold temperatures over polar regions where there is very little threat to humans. (A large hole in the ozone layer persists over Antarctica.) The discovery also links—for the first time—ozone loss (an issue around which world leaders successfully organized to ban chlorofluorocarbons, or CFCs) to climate change (a global problem that has so far proven politically intractable).
The ozone layer blocks a large fraction of the sun’s ultraviolet light from reaching the earth, protecting life forms from potentially damaging radiation that in humans can lead to skin cancer. But stratospheric ozone is susceptible to chemical catalysts of manmade origin, such as chlorine and bromine, which are present in the earth’s atmosphere as a result of the formerly widespread commercial use of CFCs. And the chemical reactions that destroy ozone are highly dependent on both atmospheric temperature and the presence of water vapor.
Anderson’s team has discovered that during intense summer storms over the United States, water vapor is thrust by convection far higher into the lower stratosphere than previously thought possible, altering atmospheric conditions in a way that leads to substantial, widespread ozone loss throughout the ensuing week. The paper links the loss of ozone over populated mid-latitude regions in summer to the frequency and intensity of these big storms, which could increase with climate change resulting from rising levels of carbon dioxide and methane in the atmosphere.