NASA & TRAPPIST-1: A Treasure Trove Of Planets Found

Three galaxies at once

Rising majestically above the telescopes of ESO’s La Silla Observatory in Chile we see the Milky Way accompanied by its two dwarf neighbour galaxies, the Large and Small Magellanic Clouds.

Credit: ESO/A. Santerne

The Perseid meteor shower over Mt. Hood

Source: https://imgur.com/ssijwh2

In this large celestial mosaic, Spitzer Space Telescope captured a stellar family portrait! You can find infants, parents and grandparents of star-forming regions all in this generational photo. ⁣ Credits:NASA/JPL-Caltech⁣

A Super-Black Coating by Surrey NanoSystems.

This product absorbs 99.7% of light at 600nm wavelength. Unlike the previous product, VantaBlack, this product is much more tolerant and can withstand handling - indicating more realistic worldwide applications. 

Star Formation in the Tadpole Nebula by Francesco Antonucci

How do you observe that the Universe is expanding? 

In 2011, the Nobel Prize in Physics was awarded to Saul Perlmutter, Brian Schmidt and Adam Riess for discovering that the Universe is expanding at an accelerating rate. We’d known for a while that the Universe has been expanding ever since its birth - but we didn’t know whether the expansion was slowing down, staying the same, or speeding up. 

So, how exactly do you discover something like this? 

Perlmutter, Schmidt, and Riess did it by observing a special type of supernovae: Type Ia supernovae. Supernovae are the explosive deaths of large stars, and they usually occur when a star runs out of fuel and collapses under its own weight, generating a shockwave that blasts its material out into space. However, this only happens when a star is big enough - the initial star has to have a critical, threshold mass, called the Chandrasekhar limit. Our sun, for example, won’t go supernova because the Chandrasekhar limit happens to be around 1.4 solar masses. When it runs out of fuel, our sun will instead gently blow off its outer layers and quietly become a dense core of carbon and oxygen, called a white dwarf. 

But here’s the kicker: not all white dwarfs stay white dwarfs. 

Some white dwarfs exist as one half of a binary system, where two stars orbit each other in a perpetual celestial dance. In some situations, the white dwarfs can actually “steal” matter from their partner star, siphoning it off and guzzling it up to grow more and more massive. Eventually, when their mass hits the Chandrasekhar limit, the white dwarf is ripped apart in a supernova. 

Image Credit

This happens in binary systems all across the Universe, and because these white dwarfs all go supernova at exactly the same mass, this means we know exactly how bright the supernovae are. When they’re observed through telescopes, some look brighter and some look fainter depending on their distance - but because we know their actual intrinsic brightness, we can work out how far away they really are. (You could do this yourself using a more earthly standard candle.) For this reason, Type Ia supernovae are called “standard candles”. 

In their observations, Perlmutter, Schmidt, and Riess realised that far away supernovae were more redshifted than the supernovae close by. “Redshift” is essentially a measure of how much the Universe has expanded since the light left the supernovae, so by comparing the distance and the redshift of the supernovae, they could create an “expansion history” of the Universe. 

This showed pretty clearly that the universe isn’t just expanding, it’s accelerating - i..e, everything’s flying apart more quickly than it was yesterday, or a century, or a billion years ago. Why? Dark energy. 

How To Help Your Anxious Partner — And Yourself

Living with anxiety can be tough — your thoughts might race, you might dread tasks others find simple (like driving to work) and your worries might feel inescapable. But loving someone with anxiety can be hard too. You might feel powerless to help or overwhelmed by how your partner’s feelings affect your daily life.

If so, you’re not alone: Multiple studies have shown that anxiety disorders may contribute to marital dissatisfaction.

“We often find that our patients’ … partners are somehow intertwined in their anxiety,” says Sandy Capaldi, associate director at the Center for the Treatment and Study of Anxiety at the University of Pennsylvania.

Anxiety is experienced at many different levels and in different forms — from moderate to debilitating, from generalized anxiety to phobias — and its impacts can vary. But psychiatrists and therapists say there are ways to help your partner navigate challenges while you also take care of yourself.

Read the full story here

The Earth from Russia’s Elektro-L satellite

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

A shot of just a tiny bit of the Andromeda Galaxy, from the sharpest ever view taken by the Hubble Space Telescope

Full size image

Bizarre planets.