Pi Day, the informal holiday beloved by math enthusiasts — and even by the math averse — is here! March 14 marks the yearly celebration of the mathematical constant π (pi).
What is Pi?
Pi (3.1415….) is the ratio of circumference to diameter in a circle. Any time you want to find out the distance around a circle when you have the distance across it, you will need this formula.
Despite its frequent appearance in math and science, you can’t write pi as a simple fraction or calculate it by dividing two integers. For this reason, pi is said to be “irrational.” Pi’s digits extend infinitely and without any pattern, adding to its intrigue and mystery.
How Do We Use Pi at NASA?
Measurements: Pi can be used to make measurements – like perimeter, area and volume.
For example, sometimes we use lasers to explode ice samples and study their composition. In this scenario, we can uses pi to calculate the width of the laser beam, which in turn can be used to calculate the amount of energy, or fluence, that hits the ice sample. A larger fluence equals a bigger explosion in the ice.
Commanding Rovers: Pi is also used every day commanding rovers on the Red Planet. Everything from taking images, turning the wheels, driving around, operating the robotic arm and even talking to Earth!
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
wait what
…
turns out that pack rats (Neotoma sp.) creates these big middens which they urinate on. The urine then crystallizes over time, creating amber-like deposits. Some of the ones found in caves are 50.000 years old and contains intact plant material, allowing scientists to analyse the prehistoric flora.
the dark deposits in the middle are 10.000+ year old crystallized rat piss
what a world
Gliese 832c: is a Potentially Habitable Super-Earth Discovered only 16 Light-Years from Earth
A team of astronomers led by Dr Robert Wittenmyer of the University of New South Wales have discovered the super-Earth. The newly discovered exoplanet, labeled Gliese 832c, has an orbital period of 35.68 days, a mass 5.4 times that of Earth’s and receives about the same average energy as Earth does from the Sun. Gliese 832c might have Earth-like temperatures, giving it a similar terrestrial atmosphere. If the planet has a similar atmosphere to Earth it may be possible for life to survive, although seasonal shifts would be extrem.
Gliese 832c was discovered from its gravitational pull on its star, which causes the star to wobble slightly.
I saw this a long time ago and finally got it to convert to GIF format on tumblr. It shows how it’s the Earth that’s moving, space is standing still. I love this perspective.
This image compilation, comprised of images taken by the Russian Elektro-L weather satellite, was taken from a geostationary orbit at a distance of 36,000 km. It shows the changing illumination of Earth as it rotated on the autumnal equinox and illustrate the concept of a geostationary orbit. At this height, the satellite is orbiting at fast as the earth is spinning and stays in the same location relative to the surface of earth.
Credit: Vitaliy Egorov
Sleep is your superpower | Matt Walker
Sleep is your life-support system and Mother Nature’s best effort yet at immortality, says sleep scientist Matt Walker. In this deep dive into the science of slumber, Walker shares the wonderfully good things that happen when you get sleep – and the alarmingly bad things that happen when you don’t, for both your brain and body. Learn more about sleep’s impact on your learning, memory, immune system and even your genetic code – as well as some helpful tips for getting some shut-eye.
ESO - European Southern Observatory logo. 13 July 2016
Artist’s impression of the water snowline around the young star V883 Orionis
The Atacama Large Millimeter/submillimeter Array (ALMA) has made the first ever resolved observation of a water snow line within a protoplanetary disc. This line marks where the temperature in the disc surrounding a young star drops sufficiently low for snow to form. A dramatic increase in the brightness of the young star V883 Orionis flash heated the inner portion of the disc, pushing the water snow line out to a far greater distance than is normal for a protostar, and making it possible to observe it for the first time. The results are published in the journal Nature on 14 July 2016.
ALMA image of the protoplanetary disc around V883 Orionis
Young stars are often surrounded by dense, rotating discs of gas and dust, known as protoplanetary discs, from which planets are born. The heat from a typical young solar-type star means that the water within a protoplanetary disc is gaseous up to distances of around 3 au from the star [1] — less than 3 times the average distance between the Earth and the Sun — or around 450 million kilometres [2]. Further out, due to the extremely low pressure, the water molecules transition directly from a gaseous state to form a patina of ice on dust grains and other particles. The region in the protoplanetary disc where water transitions between the gas and solid phases is known as the water snow line [3].
The star V883 Orionis in the constellation of Orion
But the star V883 Orionis is unusual. A dramatic increase in its brightness has pushed the water snow line out to a distance of around 40 au (about 6 billion kilometres or roughly the size of the orbit of the dwarf planet Pluto in our Solar System). This huge increase, combined with the resolution of ALMA at long baselines [4], has allowed a team led by Lucas Cieza (Millennium ALMA Disk Nucleus and Universidad Diego Portales, Santiago, Chile) to make the first ever resolved observations of a water snow line in a protoplanetary disc.
Shifting water snowline in V883 Orionis
The sudden brightening that V883 Orionis experienced is an example of what occurs when large amounts of material from the disc surrounding a young star fall onto its surface. V883 Orionis is only 30% more massive than the Sun, but thanks to the outburst it is experiencing, it is currently a staggering 400 times more luminous — and much hotter [5].
ALMA image of the protoplanetary disc around V883 Orionis (annotated)
Lead author Lucas Cieza explains: “The ALMA observations came as a surprise to us. Our observations were designed to look for disc fragmentation leading to planet formation. We saw none of that; instead, we found what looks like a ring at 40 au. This illustrates well the transformational power of ALMA, which delivers exciting results even if they are not the ones we were looking for.”
ALMA image of the protoplanetary disc around V883 Orionis
The bizarre idea of snow orbiting in space is fundamental to planet formation. The presence of water ice regulates the efficiency of the coagulation of dust grains — the first step in planet formation. Within the snow line, where water is vapourised, smaller, rocky planets like our own are believed to form. Outside the water snow line, the presence of water ice allows the rapid formation of cosmic snowballs, which eventually go on to form massive gaseous planets such as Jupiter.
Zooming on the protoplanetary disc around V883 Orionis
The discovery that these outbursts may blast the water snow line to about 10 times its typical radius is very significant for the development of good planetary formation models. Such outbursts are believed to be a stage in the evolution of most planetary systems, so this may be the first observation of a common occurrence. In that case, this observation from ALMA could contribute significantly to a better understanding of how planets throughout the Universe formed and evolved.
The protoplanetary disc around V883 Orionis (artist’s impression)
Notes: [1] 1 au, or one astronomical unit, is the mean distance between the Earth and the Sun, around 149.6 million kilometres.This unit is typically used to describe distances measured within the Solar System and planetary systems around other stars. [2] This line was between the orbits of Mars and Jupiter during the formation of the Solar System, hence the rocky planets Mercury, Venus, Earth and Mars formed within the line, and the gaseous planets Jupiter, Saturn, Uranus and Neptune formed outside. [3] The snow lines for other molecules, such as carbon monoxide and methane, have been observed previously with ALMA, at distances of greater than 30 au from the protostar within other protoplanetary discs. Water freezes at a relatively high temperature and this means that the water snow line is usually much too close to the protostar to observe directly. [4] Resolution is the ability to discern that objects are separate. To the human eye, several bright torches at a distance would seem like a single glowing spot, and only at closer quarters would each torch be distinguishable. The same principle applies to telescopes, and these new observations have exploited the exquisite resolution of ALMA in its long baseline modes. The resolution of ALMA at the distance of V883 Orionis is about 12 au — enough to resolve the water snow line at 40 au in this outbursting system, but not for a typical young star. [5] Stars like V883 Orionis are classed as FU Orionis stars, after the original star that was found to have this behaviour. The outbursts may last for hundreds of years. More information: This research was presented in a paper entitled “Imaging the water snow-line during a protostellar outburst”, by L. Cieza et al., to appear in Nature on 14 July 2016. The team is composed of Lucas A. Cieza (Millennium ALMA Disk Nucleus; Universidad Diego Portales, Santiago, Chile), Simon Casassus (Universidad de Chile, Santiago, Chile), John Tobin (Leiden Observatory, Leiden University, The Netherlands), Steven Bos (Leiden Observatory, Leiden University, The Netherlands), Jonathan P. Williams (University of Hawaii at Manoa, Honolulu, Hawai`i, USA), Sebastian Perez (Universidad de Chile, Santiago, Chile), Zhaohuan Zhu (Princeton University, Princeton, New Jersey, USA), Claudio Cáceres (Universidad Valparaiso, Valparaiso, Chile), Hector Canovas (Universidad Valparaiso, Valparaiso, Chile), Michael M. Dunham (Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA), Antonio Hales (Joint ALMA Observatory, Santiago, Chile), Jose L. Prieto (Universidad Diego Portales, Santiago, Chile), David A. Principe (Universidad Diego Portales, Santiago, Chile), Matthias R. Schreiber (Universidad Valparaiso, Valparaiso, Chile), Dary Ruiz-Rodriguez (Australian National University, Mount Stromlo Observatory, Canberra, Australia) and Alice Zurlo (Universidad Diego Portales & Universidad de Chile, Santiago, Chile). The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA. ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”. Links: Research paper: http://www.eso.org/public/archives/releases/sciencepapers/eso1626/eso1626a.pdf Photos of ALMA: http://www.eso.org/public/images/archive/search/?adv=&subject_name=Atacama%20Large%20Millimeter/submillimeter%20Array For more information about ALMA, visit: https://www.eso.org/sci/facilities/alma.html Images, Text, Credits: ESO/Richard Hook/A. Angelich (NRAO/AUI/NSF)/ALMA (ESO/NAOJ/NRAO)/ALMA//L. Cieza/IAU and Sky & Telescope/Videos: ALMA (ESO/NAOJ/NRAO)/L. Cieza./ESO/Digitized Sky Survey 2/N. Risinger (skysurvey.org)/M. Kornmesser. Music: Johan B. Monell. Best regards, Orbiter.ch Full article
The Carina Nebula - A Birthplace Of Stars
The Carina Nebula lies at an estimated distance of 6,500 to 10,000 light years away from Earth in the constellation Carina. This nebula is one of the most well studied in astrophysics and has a high rate of star formation. The star-burst in the Carina region started around three million years ago when the nebula’s first generation of newborn stars condensed and ignited in the middle of a huge cloud of cold molecular hydrogen. Radiation from these stars carved out an expanding bubble of hot gas. The island-like clumps of dark clouds scattered across the nebula are nodules of dust and gas that are resisting being eaten away by photons (particles of light) that are ionizing the surrounding gas (giving it an electrical charge).
Credit: NASA/Hubble
This is a studyblr for everyone have some passion for science, especially astronomy and biology
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