Category: space

This Is Why Sputnik Crashed Back To Earth Afte…

This Is Why Sputnik Crashed Back To Earth After Only 3 Months

“But for the 25,000+ other satellites in low-Earth orbit, there is no controlled re-entry coming. Earth’s atmosphere will take them down, extending far beyond the artificial edge of space, or Kármán line, that we typically draw. If we were to cease launching satellites today, then in under a century, there would be no remaining trace of humanity’s presence in low-Earth orbit.

Sputnik 1 was launched in 1957, and just three months later, it spontaneously de-orbited and fell back to Earth. The particles from our atmosphere rise far above any artificial line we’ve drawn, affecting all of our Earth-orbiting satellites. The farther your perihelion is, the longer you can remain up there, but the harder it becomes to send-and-receive signals from here on the surface. Until we have a fuel-free technology to passively boost our satellites to keep them in a more stable orbit, Earth’s atmosphere will continue to be the most destructive force to humanity’s presence in space.”

On October 4th, 1957, the world changed forever with the launch of Sputnik 1. One of the common questions that astronomers get asked is whether we can still see it or not. The answer surprises most people: not only can’t we see it, but it crashed back to Earth just 3 months after launch, before the United States even launched its first successful satellite: Explorer 1. Moreover, the reason this happened wasn’t due to any technical flaw or malfunction, but due to the simple physical fact that Earth’s atmosphere doesn’t end where we erroneously and arbitrarily define the “edge of space” to be. Instead, atmospheric drag affects all satellites in low-Earth orbit, and will eventually take down everything from the International Space Station to the Hubble Space Telescope.

Come find out how this works, and learn why over 95% of everything we’ve ever put in space is doomed to come back to Earth by the century’s end.

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This Is Why ‘Pillars’ In Space Mea…

This Is Why ‘Pillars’ In Space Mean Destruction, Not Creation

“In the heart of the Eagle Nebula, the iconic Pillars of Creation loom as one of Hubble’s greatest all-time sights. But very little is still being created in there, compared to the destruction that’s taking place. It’s true: there are new stars being formed inside, as the gas gravitational collapses down to grow the largest clumps of matter. But the reason you have a pillar shape at all is because of nearby, bright, external stars, which boil the gas away.”

Just because you have newly-forming proto-stars inside of you doesn’t mean you’re creating new things. You could, instead, be at the very end-stages of creation, where you’ve finished creating ~99% of everything your star-forming region is ever going to create, and only the last remnant stage — that of destruction — is left. Instead, these gas clumps are the final vestiges of an environment that houses already-born stars, in the process of boiling off. These gas globules aren’t collapsing and giving rise to stars; they’re evaporating away. What we’re witnessing is the aftermath of creation, not the start of it.

When you see phenomenal spectacular pillars in space, don’t think “creation” anymore. Destruction is far more accurate.

This Is How Astronomy Is Finally Defeating Its…

This Is How Astronomy Is Finally Defeating Its Greatest Enemy: Earth’s Atmosphere

“This is not only a tremendous boon to astronomy, but represents the potential of successful collaborations between government-funded endeavors and private industry. Without the participation of both, improvements such as these would have been impossible. With 25-to-39 meter class telescopes scheduled to come online in the coming decade, including the future ELT at 39 meters and also managed by ESO, it’s never been a better time to be a ground-based astronomer. 

For decades, the only ways to contend with the atmosphere were either to live with it or to go above it. Yet over the past few years, all of that is changing. It’s time to seriously consider outfitting all of our large observatories with adaptive optics systems like this. If these improvements continue, ground-based astronomy may be able to surpass space-based telescopes, as far as quality-imaging-per-dollar goes, once and for all!”

So, you want to view the Universe as accurately as possible, but you don’t have the ability to put your dream observatory in space? Welcome to the world of astronomy, where there’s a trade-off between what you can do from the ground (where weight and size are no concern) and what you can do from space (where you don’t have an atmosphere). The Hubble Space Telescope has been so revolutionary because of all that it could see without any atmospheric interference, but the ground is catching up. The science of adaptive optics is progressing tremendously as the years go by, enabling us to compensate for the atmosphere and. in some cases, to even defeat Hubble with telescopes here on Earth.

At last, astronomers are finally defeating their true observational nemesis: Earth’s atmosphere. This is the story of how.

The 10 Scariest Places In The Universe, Accord…

The 10 Scariest Places In The Universe, According To Science

“With a huge suite of different observatories for viewing the Universe, innumerable details can be revealed.

Occasionally, what we find evokes terrifying feelings within us.

In the spirit of Halloween, here are the top 10 scariest sights the Universe has to offer.”

From ‘Terminator Tinkerbell,’ which is merely three colliding galaxies in an unusual configuration, to the ‘Ghost Nebula,’ which looks like a group of demons emerging from a wispy space cloud, the Universe is full of sights that remind us of the occult. Skulls, eyeballs, gargoyles, and even a ghostly hand make an appearance if we know where to look. As Halloween approaches, check out these 10 scary sights that the Universe delivers to us naturally, depending on which wavelength we look in.

From galaxy clusters down to mere space rocks in our own Solar System, enjoy this astronomical treat for Halloween!

See The Universe Through The Eyes Of ALMA, The…

See The Universe Through The Eyes Of ALMA, The World’s Most Complex Telescope

“Instead of the number of wavelengths fitting across a single dish, your resolution is determined by the distance between dishes.

ALMA, the Atacama Large Millimeter/submillimeter Array, consists of 66 large radio telescopes networked together.

Combined, they measure this long-wavelength light to reveal astronomical details as never before.”

You can do so much more, in terms of resolution, with an array of telescopes than you could ever hope to do with a single dish. ALMA is presently the world’s most advanced array of infrared/radio telescopes, and by viewing individual objects with every one of their 66 dishes simultaneously, it can reveal details we’d never see otherwise. From individual galaxies, rotating or forming stars, to the signatures given off from newborn or dying stars, these images (and many more) reveal details about the Universe we’ve never known before. Most breathtaking of all, ALMA can reveal the details of a newly-formed solar system’s protoplanetary disk, including the gaps where new planets are actively forming.

There are lesson here affecting scales as large as colliding galaxies down to the tiny scales of infant planets. Come see them all today!

This Is How Hubble Will Use Its Remaining Gyro…

This Is How Hubble Will Use Its Remaining Gyroscopes To Maneuver In Space

“It might seem to be just another example of crumbling infrastructure in the United States, but you must neither underestimate Hubble nor the resourcefulness of astronomers and scientists and engineers overall. The two (or maybe three) remaining gyroscopes are of a new and upgraded design, designed to last five times as long as the original gyroscopes, which includes the one that recently failed. The James Webb Space Telescope, despite being billed as Hubble’s successor, is actually quite different, and will launch in 2021.

Even with one gyroscope, the Hubble Space Telescope should still be operational and capable of providing complementary observations to James Webb. This reduced-gyro mode has been planned for a long time. The only disappointment is that we may need to enter it so soon.”

One of the hallmarks of a successful NASA project is overengineering. Things will go wrong, break down, and degrade over time. One of the best examples is the Opportunity rover, which was designed for a 90 day mission and wound up living for nearly 15 years. But many people don’t appreciate how successfully overengineered Hubble is. Now well into its 28th year, it’s some 9 years removed from its final servicing mission. The gyroscopes that were installed included three of the old type and three of the new type, and the final old-style gyroscope has just failed. 

Yet Hubble can continue operating and doing astronomy on just one gyroscope. Its demise has been greatly exaggerated; come learn the truth about Hubble today!

These Are The Most Distant Objects We’ve…

These Are The Most Distant Objects We’ve Ever Discovered In The Universe

“For planets of any type, the quasar RX J1131-1231, lensed by rogue planets, holds the record: 3.9 billion light-years distant. The most distant normal star is known as Icarus, 9 billion light-years away, lensed and magnified by a massive galaxy cluster. 23 billion light-years away is the most distant supernova ever seen: SN 1000+0216.”

Our quest to learn about the Universe is a quest of ever-receding horizons. From planets, moons, and other objects in our Solar System to stars, galaxies, quasars, and gamma-ray bursts, we just keep shattering records as far distance goes. Improvements in technology, technique, and increased observing time allow us to reveal things that simply couldn’t be observed previously. Yet we’re by no means done, just because we’ve set a slew of new records in the opening two decades of the 21st century. With the launch of the James Webb Space Telescope, the hope of a Planet Nine, and the advent of 30-meter-class astronomy from the ground, the records we know and adore today may all be in the rear-view mirror just a few years from now.

What are the most distant objects of all different types in the Universe? Get the 2018 update right now!

These Are The Last Galaxies That Will Remain I…

These Are The Last Galaxies That Will Remain In Our Night Sky

“But beyond our backyard, all the other galaxies, groups, and clusters are accelerating away from us.

Once you go about 4-5 million light years away, dark energy causes space to expand faster than gravity attracts other objects across space.

Over time, every other galaxy will see its distance and recession speed increase from our perspective.”

Our Universe isn’t only expanding, but is accelerating. This means that every galaxy, group, or cluster that isn’t already gravitationally bound to us is receding from us at a faster and faster rate as time goes on. With 2 trillion galaxies in the observable Universe, only approximately 70 of them are bound to our Local Group. Everything farther than about 4 or 5 million light years away from us is unbound, and therefore will recede from us forever and ever, with their recession speeds and cosmic distances increasing over time.

Here are the last galaxies we’ll ever be able to see or visit, as the relentless expansion of the Universe causes their disappearance from our cosmic horizon.

There are the Sketches of the four moons of Jupiter (Io,…

There are the Sketches of the four moons of Jupiter (Io, Europa, Ganymede and Callisto), as seen by Galileo
through his telescope.

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The drawing depicts observations from the time period January 7 to 24, 1610.

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The above is the sequence of photographs taken by JunoCam aboard the Juno
spacecraft, in June 2016, of Jupiter and the motion of the four Galilean
moons, as the spacecraft approached the planet.

* There are 79 known moons of Jupiter.

** Jupiter has 4 rings.