The diffuse heliospheric current extends to th…

The diffuse heliospheric current extends to the outer regions of the Solar System, and results from the influence of the Sun’s rotating magnetic field on the plasma in the interplanetary medium. source.

Adoro suas explorações. Ent&ati…

Adoro suas explorações. Então poderia me falar da formação do sol e dar exemplos de hidrogênio e Hélio e o que tem haver com a fonte de energia que alimenta a terra.

Obrigado. A teoria mais aceita é que o Sol se formou de uma nuvem molecular, essa nuvem molecular entrou em colapso causado por alguma perturbação, como por exemplo, ondas de choque de uma supernova que explodiu próximo dessa nuvem. A partir dai a gravidade entra em ação e faz o mecanismo de ‘’juntar’’ a nuvem de gás e poeira  o suficiente para comprimi-la até formar uma protoestrela. Depois dessa fase o Sol entrou no que é conhecido como Sequência principal. Estrelas que entram na fase de Sequência Principal são estrelas que queimam hidrogênio em Hélio (através da fusão nuclear) e é esse mecanismo que faz o Sol brilhar e gerar o calor que chega até nós.

Hi! I really love astronomy and I would love t…

Hi! I really love astronomy and I would love to learn about it. Can you tell me some apps or books you recommend about space?? 💕

Books:

  • Astronomy (Eyewitness Companions) by Ian Ridpat
  • Astrophysics for People in a Hurry – Neil deGrasse Tyson
  • A Brief History of Time – Stephen Hawking 

  • Physics of the Impossible – Michio Kaku
  • The Elegant Universe – Brian Greene
  • The Fabric of the Cosmos – Brian Greene

Apps: 

  • Stellarium
  • ISS HD Live
  • Solar System Explorer
  • Exoplanet Explorer
  • Star Chart

Observations of Earth, Soyuz, Aurora, moon and…

Observations of Earth, Soyuz, Aurora, moon and Space Shuttle Endeavor made from the International Space Station.

source: images.nasa.gov

Orion’s Powerhouse : A technician works on the…

Orion’s Powerhouse : A technician works on the European Service Module that will propel the Orion spacecraft in space and provide air, water and electricity for future crews. (via NASA)

If someone wants to know about astronomy from …

If someone wants to know about astronomy from a simple, understood source, what should he read?

Reliable astronomy websites (nasa.gov, phys.org, esa.int, eso.org, sci-news.com), sites like wikipedia and solarsystem.nasa.gov can also help, and especially books.

hi! would you please explain the concept of Wh…

hi! would you please explain the concept of White Holes? thank you!

I already made a post about it, click here.

I was wondering if you could go in depth, at l…

I was wondering if you could go in depth, at least to a degree about how incredibly dense objects have strong enough gravity to distort light. To me that's one of the wildest concepts I can imagine, not that I expect you to be all knowing but maybe you've got a good article or something? I don't recall if you've ever made posts about the theory of relativity. Sorry for the long ask!

Well, I know only the basics, things I study in my free time, however, I can try to explain. The distortion of space-time is described by Einstein’s Theory of General Reality. The more massive an object, the more its curvature will be in the space-time fabric.

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This distortion in light is known as a gravitational lensing. The gravitational lensing is formed due to a space-time distortion caused by the presence of a large mass body between a distant light source and an observer.

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These distortions are widely observed through globular clusters.

Since the amount of lensing depends on the total mass of the cluster, gravitational lensing can be used to ‘weigh’ clusters. This has considerably improved our understanding of the distribution of the ‘hidden’ dark matter in galaxy clusters and hence in the Universe as a whole. The effect of gravitational lensing also allowed a first step towards revealing the mystery of the dark energy.

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As gravitational lenses function as magnification glasses it is possible to use them to study distant galaxies from the early Universe, which otherwise would be impossible to see.

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Gravitational lensing happens on all scales – the gravitational field of galaxies and clusters of galaxies can lens light, but so can smaller objects such as stars and planets. Even the mass of our own bodies will lens light passing near us a tiny bit, although the effect is too small to ever measure.

Destination: History : On Feb. 20, 1962, John …

Destination: History : On Feb. 20, 1962, John Glenn made history by becoming the first U.S. astronaut to orbit the place we call home–planet Earth. (via NASA)

What would cause two stars to collide? What do…

What would cause two stars to collide? What does it take for a whole planet (as massive as Jupiter) to change trajectory?

The main mechanism that would make two stars collide is gravity. This depends on several factors, some stars may wander through space and end up being attracted by the gravitational field of another star, from there, one star begins to orbit the other. 

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But the most common are collisions in clusters of stars, because in a star cluster the stars are very close together, especially in globular clusters. 

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Collisions of young stars may also occur, as most of the stars are born close to each other in clusters. Many stars are binary, formed together, but in some cases before they evolve they may end up colliding.

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In the universe both collisions of active stars can occur, as can collisions of white dwarfs, neutron stars and black holes.

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The orbits of the planets are determined by the gravitational pull of the Sun, so it would need some very extreme force to cause the orbit of a planet to change its trajectory, perhaps if some planet or star enters our solar system, or when the Sun goes through changes and become a white dwarf in about 5 billion years.