every week, or TechWorld The #AstroMiniBR brings together five relevant and fun astronomical curiosities produced by the collaborators of non-Twitter profile to disseminate or know about the science that is the oldest of all!

#1: Why does Terra change seasons during the year?

Muitas pessoas acreditam que as estações do ano acontecem por causa da distância da Terra ao Sol, mas isso não é verdade...

A Terra tem estações porque seu eixo de rotação é inclinado! Durante o ano, diferentes partes da Terra recebem raios do Sol diretamente!#AstroMiniBR pic.twitter.com/A38pCL1YCX

— Giovanna Liberato (@liberato_gio) June 20, 2022

It is not common to believe that Terra is closer to the sun than it will be and for this reason it is more than this time of the year. And, in the same way, when Terra is more distant from the Sun, it happens in winter with its colder temperatures. Embora essa ideia faça felt intuitively, ela é incorrect.

In fact, the trajectory of the Earth around the Sun, this is, its orbit, is not a perfect circle and this asymmetry face with which the Earth is closer and more distant from the Sun at different times of the year. Therefore, this difference is not enough to make a significant change, not our climate and not the main reason why we have seasons of the year.

Due to the fact that the seasons occur, it is the fact that the terrestrial rotation axis – this is, or the imaginary one in which the Earth rotates around itself, causing at night and day – to be tilted in relation to its orbital plane. The terrestrial sun is always pointed in the same direction, so different parts of the Earth receive the direct rays of the Sun in different ways throughout the year. For example, it will not see, the rays of the sun reach that region more directly than in any other time of the year, so it happened that it did not winter with an incidence of two solar rays or less.

#2: We are ugly for star poetry

Somos feitos de poeira da estrelas... mas quanto?

Nosso corpo possui cerca de 7 x 10^27 átomos, sendo 40% deles poeira estelar.

Como esses átomos são elementos mais pesados, a porcentagem de nossa "massa estelar" é mais impressionante: 93%! #AstroMiniBR

via @Rainmaker1973 pic.twitter.com/2digMEXPxV

— Nícolas Oliveira (@nicooliveira_) June 23, 2022

Did you ever wonder where you saw it? From where will all this structure that makes up our organs, muscles and bones arise? Of course, you could think “everything is my life” and that would certainly be true, because, at a more fundamental level, everything in us and everything here that we manage to see and touch the fact of particles, atoms and molecules.

And where did you see these small ingredients?

This answer goes back to billions of years ago and has a cosmic origin. The ingredients carbon, hydrogen, nitrogen, oxygen, phosphorous and oxide are the fundamental building blocks of all life on Earth. Now it has a strongly poetic connotation, the statement “we are feitos de poeira stellar” possesses a broad scientific truth: all the heaviest chemical elements that are not in our organism (and also in all the things that exist) such as, for example, the atoms of carbon, nitrogen and oxygen, forams raised in previous generations of stars have more than 4.5 billion years.

In our case, about 40% of all of our atoms are forged in the stars, while most of the hydrogen was formed in the primordial universe, later logo or Big Bang. Therefore, as these 40% of atoms are precisely the heaviest chemical elements, or the total of our mass that was made in the stars reaches 93%!

#3: When will the first stars and galaxies arise in the Universe?

O universo tem cerca de 13.500.000.000 anos (ou seja, 13,5 bilhões de anos). Os primeiros seres humanos surgiram há bem menos de 4 milhões de anos.

Mas as primeiras estrelas e galáxias já surgiram no primeiro bilhão de ano do universo! ???? #AstroMiniBR pic.twitter.com/OLDFenb55U

— Ana Carolina Posses (@astroposses) June 22, 2022

To answer this question, there is no moment in which the Universe is still engatinhava in its existence. The first stars were likely to form when the Cosmos was about 100 thousand years old, before the formation of the first galaxies.

As the elements that make up most of the planet Earth still had not been formed, these primordial objects, known as stars of the population III, were made entirely of hydrogen and helium. Ao will explode as supernovae, we will expel heavy elements produced in their interiors for interstellar medium. It is the beginning of the cosmic chemical enrichment that led to the formation of other stars, including the ones we see in the Milky Way. The first generation of galaxies possibly originated a few times, between 200 and 400 thousand years ago or the Big Bang, when the first stars and the surrounding material of gas and cosmic energy coalesced due to gravitational influence.

#4: A beauty two berçários de estrelas

uma equipe de astrônomas/os mapeou o gás na Nebulosa da Tarântula ???
esse objeto abriga berçarios de estrelas muito brilhantes e massivas -- e se localiza fora da Via-Láctea, na galáxia satélite da Grande Nuvem de Magalhães ??#AstroMiniBR (1/2) pic.twitter.com/zzBOxV4EbE

— yanna martins franco (@martins_yanna) June 17, 2022

Distant about 170 thousand light-years away from us, the beautiful Tarantula Nebula possesses a spectacular set of stellar berçários. Present in one of our closest galactic vizinhas, the Grande Nuvem de Magalhães, the Tarantula Nebulosa with clouds of power and colossal gas that gave rise to new stars over a thousand years.

The shapes of these clouds are constantly shaped by these dynamics of star formation as new bright and extremely hot stars are created.

In the images above it is possible to see an animation showing the combination of the observations of the beautiful nebula and the compression of the optical wave, the infrared wave and the radio wave.

#5: To Nebula do Veu

?? REMANESCENTE DE SUPERNOVA

Essa é a Nebulosa do Véu, localizada há aprox 1400 anos-luz de distância.
Imagine a surpresa de quem vivia há 10mil anos vendo uma luz surgir de repente no céu e ficar lá por semanas: estavam assistindo à explosão de uma estrela.#AstroMiniBR pic.twitter.com/anwPWbDqnL

— Thiago Flaulhabe (@TFlaulhabe) June 22, 2022

The image above shows the Nebula do Véu, distant about 2,400 light-years from the Solar System. It is a huge cloud of heated and ionized gas and energy that are remnants of a supernova that occurred about 10 to 20 thousand years ago. A source of this cataclysmic event was a star about 20 times more massive than the Sun and, at the time of the explosion, its light would have appeared brighter than Venus would not have been visible even during the day here on Earth.