Space Infographicsby Nick Wiinikka

New Supernova Results: Is The Universe Not Accelerating?

“There actually is a nice result from this paper: it perhaps will cause a rethink of the standard likelihood analysis used by teams analyzing supernova data. It also shows just how incredible our data is: even with using none of our knowledge about the matter in the Universe or the flatness of space, we can still arrive at a better-than-3σ result supporting an accelerating Universe. But it also underscores something else that’s far more important. Even if all of the supernova data were thrown out and ignored, we have more than enough evidence at present to be extremely confident that the Universe is accelerating, and made of about 2/3 dark energy.”

Just a few days ago, a new paper was published in the journal Scientific Reports claiming that the evidence for acceleration from Type Ia supernovae was much flimsier than anyone gave it credit for. Rather than living up to the 5-sigma standard for scientific discovery, the authors claimed that there was only marginal, 3-sigma evidence for any sort of acceleration, despite having statistics that were ten times better than the original 1998 announcement. They claimed that an improved likelihood analysis combined with a rejection of all other priors explains why they obtained this result, and use it to cast doubt on not only the concordance model of cosmology, but on the awarding of the 2011 Nobel Prize for dark energy. Despite the sensational coverage this has gotten in the press, the team does quite a few things that are a tremendous disservice to the good science that has been done, and even a simplistic analysis clearly debunks their conclusions.

Dark energy and acceleration are real and here to stay. You owe it to yourself to find out why and how!

The Cat’s Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its more familiar outlines are seen in the brighter central region of the nebula in this impressive wide-angle view. But the composite image combines many short and long exposures to also reveal an extremely faint outer halo. At an estimated distance of 3,000 light-years, the faint outer halo is over 5 light-years across. Planetary nebulae have long been appreciated as a final phase in the life of a sun-like star. More recently, some planetary nebulae are found to have halos like this one, likely formed of material shrugged off during earlier episodes in the star’s evolution. While the planetary nebula phase is thought to last for around 10,000 years, astronomers estimate the age of the outer filamentary portions of this halo to be 50,000 to 90,000 years. Visible on the left, some 50 million light-years beyond the watchful planetary nebula, lies spiral galaxy NGC 6552.

Object Names: Cat’s Eye Nebula, NGC 6543

Image Type: Astronomical

Credit: Josh Smith (Via Nasa)

Time And Space

9 Squares 8

Top: David Stanfield, Skip Hursh, Jamie Muntean Middle: David Urbinati, Al Boardman, Jake Williams Bottom: Riccardo Albertini, Bee Grandinetti, Qais Sarhan

About the project

NASA logo. April 27, 2015 As the saying goes, timing is everything. More so in 21st-century space exploration where navigating spacecraft precisely to far-flung destinations—say to Mars or even more distant Europa, a moon of Jupiter—is critical. NASA is making great strides...

The Great Nebula in Carina : In one of the brightest parts of Milky Way lies a nebula where some of the oddest things occur. NGC 3372, known as the Great Nebula in Carina, is home to massive stars and changing nebulas. The Keyhole Nebula , the bright structure just above the image center, houses several of these massive stars and has itself changed its appearance. The entire Carina Nebula spans over 300 light years and lies about 7,500 light-years away in the constellation of Carina. Eta Carinae, the most energetic star in the nebula, was one of the brightest stars in the sky in the 1830s, but then faded dramatically. Eta Carinae is the brightest star near the image center, just left of the Keyhole Nebula. While Eta Carinae itself maybe on the verge of a supernova explosion, X-ray images indicate that much of the Great Carina Nebula has been a veritable supernova factory. via NASA

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death of a star by a supernova explosion,

and the birth of a black hole

Pitch Black: Cosmic Clumps Cast the Darkest Shadows

Astronomers have found cosmic clumps so dark, dense and dusty that they throw the deepest shadows ever recorded. Infrared observations from NASA’s Spitzer Space Telescope of these blackest-of-black regions paradoxically light the way to understanding how the brightest stars form.

The clumps represent the darkest portions of a huge, cosmic cloud of gas and dust located about 16,000 light-years away. A new study takes advantage of the shadows cast by these clumps to measure the cloud’s structure and mass.

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We’re used to radiation being invisible. With a Geiger counter, it gets turned into audible clicks. What you see above, though, is radiation’s effects made visible in a cloud chamber. In the center hangs a chunk of radioactive uranium, spitting out alpha and beta particles. The chamber also has a reservoir of alcohol and a floor cooled to -40 degrees Celsius. This generates a supersaturated cloud of alcohol vapor. When the uranium spits out a particle, it zips through the vapor, colliding with atoms and ionizing them. Those now-charged ions serve as nuclei for the vapor, which condenses into droplets that reveal the path of the particle. The characteristics of the trails are distinct to the type of decay particle that created them. In fact, both the positron and muon were first discovered in cloud chambers! (Image credit: Cloudylabs, source)

A little more help for focusing-on beginers: In terms of cognitive demand, it is more difficult to focusing on your ongoing task when you have a long to-do list than when only a few more tasks left. So I recommend you to try making schedule with less than 5 tasks a day. It will be much easier to organize work of different fields or of different shades of cognitive demand.

How focusing (aka. not multi-tasking) changed my study life

I had heard it occasionally - that multi-tasking was actually not good for the quality of whatever task I was doing. It made sense, but I loved mult-tasking so much. It gave me the illusion of productivity. 

Until I actually tried focusing for a while, did I realise how much I was actually losing by multi-tasking -  educationally and emotionally. Scrolling through tumblr during boring parts of a lecture seemed fine, since there were notes and it probably wouldn’t be tested in such depth anyway. Eating, while scrolling through social media, while watching a tv show, while messaging someone on facebook seemed ‘productive’. 

It turns out it was the opposite. It may seem fine, and at times it may actually be okay, but what matters is the principle. Dedicating your whole being to one task, focusing on it, produces much better results. It’s a quality over quantity thing. It also helped to calm me down emotionally - I used to always feel rushed, like there was so many things to do but not enough time to do them. Focusing on one task at a time - though it was hard at first - helped slow me down because I did everything properly, and didn’t have the feeling like I needed to go back and do things over again. 

Focusing on one thing wholly is also a form of practising mindfulness. Mindfulness ‘meditation’ isn’t something that requires you to sit down and meditate - it can be applied to our daily life. 

Since I started practising this mindful skill of focus, I’ve become much calmer, it’s been so much easier to stay on top of my work load and meet deadlines, I don’t feel rushed, I don’t feel unprepared or unorganised, and I do more quality work than when I used to multi-task.

There are times for multi-tasking and times for focus. Find the right balance and enjoy the task in front of you.