space Archives

July 7, 2014March 1, 2017 by Fraser Cain

How Many Ways Can the Sun Kill You?

The Sun has a Swiss army knife of ways it can do you in, from radiation to solar flares. And when it dies, it’s taking you with it. What are the various ways the Sun can do you in?

There’s a terrifying ball of fire a short 150 million km away. Which, in galactic terms, is right on our doorstep. This super-heated ball of plasma-y death, has temperatures and pressures so high that atoms of hydrogen are crushed into helium.

We’ve told ourselves we’re a safe distance away, and generally understate the dangers of being gravitationally bound to a massive ongoing nuclear explosion which is catastrophically larger than anything we’ve ever managed to create here on Earth. We take its warmth and life-giving light for granted, and barely give it a second thought as we sunbathe, or laugh gregariously while frying eggs on sidewalks on days when it’s scorchingly hot out.

Have we been lulled into a false sense of security by an ancient and secret society of bananas crazy sun cultists? Instead of worshiping the giant BBQ death ball, should we be cowering in fear, waiting for the next great solar flare? So, how dangerous is that thing? What are all the ways the Sun could do us in? And how many of them does my insurance cover?

First, in 4.5 billion years nothing has managed to destroy our planet. In fact, life itself has existed for almost Earth’s entire history, and nothing has scoured the planet clear of all forms of life. So, don’t worry the most reasonable risk we face from the Sun in our lifetimes is from a solar flare – a sudden blast of brightness on the surface of the Sun.

These occur when the Sun’s magnetic field lines snap and reconfigure, releasing an enormous amount of energy. It’s the equivalent of hundreds of billions of tonnes of TNT and if we’re staring down the barrel of this blast, it’ll fire a stream of high energy particles right up our nose.

Fortunately, the Earth has evolved in a highly radioactive environment. We’re blasted by radiation from the Sun all the time. The Earth’s magnetic field lines channel the particles towards the poles, which is why we get to see the beautiful auroral displays.

We’re at little risk from flares from the Sun, but our technology isn’t so lucky. The increase of geomagnetic activity in our vicinity can overload electrical grids and take satellites offline. The most powerful geomagnetic storm in history, known as the Carrington Event in 1859, generated auroras as far south as Cuba. It didn’t cause any damage then, but it would cause a lot of damage to our fragile technology today.

For those of you now resting comfortably I say… Not so fast. This episode isn’t over yet. Our Sun is heating up, and its energy output is increasing.

As it uses up the hydrogen in its core, this region of the Sun contracts a little, and the Sun increases in temperature to balance things out. Over the next few hundred million years, temperatures on Earth will rise and rise. Within a billion years, the surface of the planet will be an inhospitable oven.

Mercury seen by Mariner 10. Image credit: NASA — The Earth will one day be as dry and baked as Mercury. Image credit: NASA

Eventually the oceans will boil and the hydrogen will be blown out of the atmosphere by the Sun’s solar wind. Even though the Sun will remain in its main sequence phase for another 4 billion years after that, any life will need to be living underground.

Of course, as we’ve discussed in previous episodes, the Sun’s final act of destruction will happen when it runs out of hydrogen fuel in its core. The core will contract and the Sun will puff up into a red giant, consuming the orbits of Mercury, Venus and possibly the Earth. And even if it doesn’t consume the Earth, it’ll hit our planet with so much heat and radiation that it’ll finally get around to scouring any life off the surface.

So, like your fanatical sun cultist friends. Don’t worry about the Sun. It might make sense to keep some spare batteries around for the times when solar flares knock out the lights for a few days, but the Sun is remarkably safe and stable. We’ve got billions of years of warm light and heat from our star. But after that, it might make sense to shop for a new home.

So what do you think? Where do you think we should move when the temperature of the Sun heats up?

June 23, 2014March 1, 2017 by Fraser Cain

What Does a Supernova Sounds Like?

We’ve all been ruined by science fiction, with their sound effects in space. But if you could watch a supernova detonate from a safe distance away, what would you hear?

Grab your pedantry tinfoil helmet and say the following in your best “Comic Book Guy” voice: “Don’t be ridiculous. Space does not have sound effects. You would not hear the Death Star exploding. That is wrong.” There are no sounds in space. You know that. Why did you even click on this?

Wait! I still have thing I want to teach you. Keep that tinfoil on and stick around. First, a quick review. Why are there sounds? What are these things we detect with our ear shell-flaps which adorn the sides of our hat-resting orb?

Sounds are pressure waves moving through a medium, like air, water or beer. Talking, explosions, and music push air molecules into other molecules. Through all that “stuff” pushing other “stuff” it eventually pushes the “stuff” that we call our eardrum, and that lets us hear a thing. So, much like how there’s not enough “stuff” in space to take a temperature reading. There’s not enough “stuff” in space to be considered a medium for sound to move through.

Don’t get me wrong there’s “stuff” there. There’s particles. Even in intergalactic depths there are a few hundred particles every cubic meter, and there’s much more in a galaxy. They’re so far apart though, the particles don’t immediately collide with each other allowing a sound wave to pass through a grouping of them.

So, even if you did watch the Death Star explode, you couldn’t hear it. This includes zapping lasers, and exploding rockets. Unless two astronauts touched helmets together, then they could talk. The sound pressure moves through the air molecules in one helmet, through the glass transferring from one helmet to the other, and then pushes against the air inside the helmet of the listening astronaut. Then they could talk, or possibly hear one another scream, or just make muffled noises under the face-hugger that had been hiding in their boot.

There’s no sound in space, so you can’t hear what a supernova sounds like. But if you’re willing to consider swapping out your listening meats for other more impressive cybernetic components, there are possibilities. Perhaps I could offer you something in a plasma detection instrument, and you could hear the Sun.

Artist's concept of NASA's Voyager spacecraft. Image credit: NASA/JPL-Caltech — Artist’s concept of NASA’s Voyager spacecraft. Image credit: NASA/JPL-Caltech

Voyager 1 detects waves of particles streaming from the Sun’s solar wind. It was able to hear when it left the heliosphere, the region where the Sun’s solar wind buffets against the interstellar medium.

Or you could try something in the Marconi Auralnator 2000 which is the latest in radio detector implants I just made up. If there was such a thing, you could hear the plasma waves in Earth’s radiation belts. Which would be pretty amazing, but perhaps somewhat impractical for other lifestyle purposes such as watching Ellen.

So, if you wanted to hear a supernova you’d need a different kind of ear. In fact, something that’s not really an ear at all. There are some exceptions out there. With dense clouds of gas and dust at the heart of a galaxy cluster, you could have a proper medium. NASA’s Chandra X-Ray Observatory has detected sound waves moving through these dust clouds. But you would need ears millions of billions of times more sensitive to hear them.

NASA and other space agencies work tirelessly to convert radio, plasma and other activity into a sound pressure format that we can actually hear. There are beautiful things happening space. I’ve included a few links below which will take you to a few of these, and they are really quite incredible.

Earthsong

Lightning on Saturn, Helium in the atmosphere, etc.

June 18, 2014December 23, 2015 by Jason Major

Mercury’s Hot Flow Revealed by MESSENGER

A hot flow anomaly, or HFA, has been identified around Mercury (Credit: NASA/Duberstein)

Our Sun is constantly sending a hot stream of charged atomic particles out into space in all directions. Pouring out from holes in the Sun’s corona, this solar wind flows through the Solar System at speeds of over 400 km/s (that’s 893,000 mph). When it encounters magnetic fields, like those generated by planets, the flow of particles is deflected into a bow shock — but not necessarily in a uniform fashion. Turbulence can occur just like in air flows on Earth, and “space weather” results.

One of the more curious effects is a regional reversal of the flow of solar wind particles. Called a “hot flow anomaly,” or HFA, these energetic phenomena occur almost daily in Earth’s magnetic field, as well as on Jupiter and Saturn, and even on Mars and Venus where the magnetic fields are weak (but there are still planets blocking the stream of charged particles.)

Not to be left out in the cold, Mercury is now known to display HFAs, which have been detected for the first time by the MESSENGER spacecraft.

A NASA news release describes how the HFAs were confirmed:

The first measurement was of magnetic fields that can be used to detect giant electric current sheets that lead to HFAs. The second was of the heating of the charged particles. The scientists then analyzed this information to quantify what kind of turbulence exists in the region, which provided the final smoking gun of an HFA.

“Planets have a bow shock the same way a supersonic jet does,” explains Vadim Uritsky at NASA’s Goddard Space Flight Center. “These hot flow anomalies are made of very hot solar wind deflected off the bow shock.”

The different colors in this MESSENGER image of Mercury indicate the chemical, mineralogical, and physical differences between the rocks that make up the planet’s surface. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington. — Enhanced-color image of Mercury indicating the chemical and physical differences across its surface. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.

The solar wind is not 100% uniform; it has discontinuities within its own complex magnetic fields. When these shifting fields pile up against a planet’s bow shock they can create turbulence patterns that trap hot plasma, which in turn produces its own magnetic fields. The shockwaves, heat, and energy produced are powerful enough to actually reverse the flow of the solar wind within the HFA bulge.

And the word “hot” is putting it lightly — plasma temperatures in an HFA can reach 10 million degrees.

Mercury may be only a little larger than our Moon but it does possess an internally-generated dipolar magnetic field, unlike the Moon, Venus, and Mars which have only localized or shallow fields. The confirmed presence of HFAs on Mercury indicates that they may be a feature in all planetary bow shocks, regardless of how their magnetic fields — if any — are produced.

The team’s results were published in the February 2014 issue of the Journal of Geophysical Research: Space Physics.

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In related news, on June 17 MESSENGER successfully completed the first orbit adjustment maneuver to prepare it for its new — and final — low-altitude campaign, during which it will obtain its highest-resolution images ever of the planet’s surface and perform detailed investigations of its composition and magnetic field. Read more on the MESSENGER site here.

Source: NASA

June 16, 2014April 26, 2016 by Jason Major

New Horizons Wakes Up for the Summer

While many kids in the U.S. are starting their school summer vacations, New Horizons is about to get back to work! Speeding along on its way to Pluto the spacecraft has just woken up from hibernation, a nap it began five months (and 100 million miles) ago.

The next time New Horizons awakens from hibernation in December, it will be beginning its actual and long-awaited encounter with Pluto! But first the spacecraft and its team have a busy and exciting summer ahead.

New Horizons Tweeted about its Father's Day wakeup call — New Horizons tweeted about its Father’s Day wakeup call

After an in-depth checkout of its onboard systems and instruments, the New Horizons team will “track the spacecraft to refine its orbit, do a host of instrument calibrations needed before encounter, carry out a small but important course correction, and gather some cruise science,” according to principal investigator Alan Stern in his June 11 update, aptly titled “Childhood’s End.”

What’ll be particularly exciting for us space fans is an animation of Pluto and Charon in motion around each other, to be made from new observations to be acquired in July. Because of New Horizons’ position, the view will be from a perspective not possible from Earth.

New Horizons LOng Range Reconnaissance Imager (LORRI) composite image showing the detection of Pluto’s largest moon, Charon, cleanly separated from Pluto itself. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute) — New Horizons LOng Range Reconnaissance Imager (LORRI) image of Pluto and Charon from July 2013 (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)

The next major milestone for New Horizons will be its crossing of Neptune’s orbit on August 25. (This just happens to fall on the 25th anniversary of Voyager 2’s closest approach in 1989.) “After that,” Stern says, “we’ll be in ‘Pluto space!'”

Launched on Jan. 19, 2006, New Horizons will make its closest approach to Pluto on July 14, 2015 at 11:49 UTC. Traveling nearly 35,000 mph (55,500 km/h) it’s one of the fastest vehicles ever built, moving almost 20 times faster than a bullet.

Read more from Alan Stern in his latest “PI Perspective” article on the New Horizons web site here, and check out NASA’s mission page here for the latest news as well.

“There is a lot to tell you about over the next 12 weeks, and this is just the warm-up act. Showtime — the start of the encounter — begins in just six months. This is what New Horizons was built for, and what we came to do. In a very real sense, the mission is emerging into its prime.”

– Alan Stern, New Horizons principal investigator

Also, check out a video on Pluto and the New Horizons mission here.

June 9, 2014March 1, 2017 by Fraser Cain

Why is the Moon Leaving Us?

Goodbye Moon. Every year, the Moon slips a few centimeters away from us, slowing down our day. Why is the Moon drifting away from us, and how long will it take before the Earth and the Moon are tidally locked to each other?

We had a good run, us and the Moon. Grab your special edition NASA space tissues because today we’re embarking on a tale of orbital companionship, childhood sweethearts and heartache.

You could say we came from the same part of town. A long time ago the Mars-sized object Theia, collided with the Earth and the Moon was formed out of the debris from the collision.

We grew up together. Counting from the very beginning, this relationship has lasted for 4.5 billion years. We had some good times. Some bad times. Gravitationally linked, arm in arm, inside our solar family sedan traversing the galaxy.

But now, tragedy. The Moon, OUR Moon, is moving on to brighter horizons. We used to be much closer when we were younger and time seemed to fly by much faster. In fact, 620 million years ago, a day was only 21 hours long. Now they’ve dragged out to 24 hours and they’re just getting longer, and the Moon is already at a average distance of 384,400 km. It almost feels too far away.

If we think back far enough to when we were kids, there was a time when a day was just 2 – 3 hours long, and the Moon was much closer. It seemed like we did everything together back then. But just like people, massive hunks of rock and materials flying through space change, and their relationships change as well.

Our therapist told us it wasn’t a good idea to get caught up on minutiae, but we’ve done some sciencing using the retroreflector experiments placed by Apollo astronauts, and it looks as though the Moon has always had one foot out the door.

Today it’s drifting away at 1-2 cm/year. Such heartache! We just thought it seemed like the days were longer, but it’s not just an emotional effect of seeing our longtime friend leaving us, there’s a real physical change happening. Our days are getting 1/500th of a second longer every century.

I can’t help but blame myself. If only we knew why. Did the Moon find someone new? Someone more attractive? Was it that trollop Venus, the hottest planet in the whole solar system? It’s really just a natural progression. It’s nature. It’s gravity and tidal forces.

And no, that’s not a metaphor. The Earth and the Moon pull at each other with their gravity. Their shapes get distorted and the pull of this tidal force creates a bulge. The Earth has a bulge facing towards the Moon, and the Moon has a more significant bulge towards the Earth.

A series of photos combined to show the rise of the July 22, 2013 ‘super’ full moon over the Rocky Mountains, shot near Vail, Colorado, at 10,000ft above sea level in the White River National Forest. Moon images are approximately 200 seconds apart. Credit and copyright: Cory Schmitz

These bulges act like handles for gravity, which slows down their rotation. The process allowed the Earth’s gravity to slow the Moon to a stop billions of years ago. The Moon is still working on the Earth to change its ways, but it’ll be a long time before we become tidally locked to the Moon.

This slowing rotation means energy is lost by the Earth. This energy is transferred to the Moon which is speeding up, and as we’ve talked about in previous episodes the faster something orbits, the further and further it’s becomes from the object it’s orbiting.

Will it ever end? We’re so attached, it seems like it’ll take forever to figure out who’s stuff belongs to who and who gets the dog. Fear not, there is an end in sight. 50 billion years from now, 45 billion years after the Sun has grown weary of our shenanigans and become a red giant, when the days have slowed to be 45 hours long, the Moon will consider itself all moved into its brand new apartment ready to start its new life.

What about the neighbors down the street? How are the other orbital relationships faring. I know there’s a lot of poly-moon-amory taking place out there in the Solar System. We’re not the only ones with Moons tidally locked. There’s Phobos and Deimos to Mars, many of the moons of Jupiter and Saturn are, and Pluto and Charon are even tidally locked to each other, forever. Now’s that’s real commitment. So, in the end. The lesson here is people and planets change. The Moon just needs its space, but it still wants to be friends.

What do you think? If you were writing a space opera about the Earth and the Moon break-up, what was it that finally came between them? Tell us in the comments below.

June 2, 2014December 23, 2015 by Jason Major

Stunning Snapshots from Space Courtesy of Reid Wiseman

Sunset-lit clouds swirl over Perth on May 31, 2014 (Reid Wiseman/NASA)

On May 28 the crew of Expedition 40/41 launched from Baikonur Cosmodrome, their Soyuz TMA-13M arriving at the International Space Station about eight and a half hours later. And it didn’t take much time for the newly-arrived NASA astronaut Reid Wiseman to start taking photos from his new vantage point in orbit and sharing them on Twitter for the rest of us to enjoy! Here are some of Reid’s latest images from the edge of space, looking down on the beautiful blue world we call home.

One of Reid Wiseman's first few tweets from space — One of Reid Wiseman’s first few tweets from space!

A "beautiful pass over the Falkland Islands" (aka Malvinas) on May 30 with docked Soyuz in the foreground — A “beautiful pass over the Falkland Islands” (aka Islas Malvinas) on May 30 with docked Soyuz in the foreground

Reid confirmed that the Earth is indeed round with a 12mm lens on June 1

Looking down on glacial flows near the Strait of Magellan

Pink clouds at sunset may look beautiful from Earth but "not as pretty here" according to Reid Wiseman — Pink clouds at sunset may look beautiful from Earth but “not as pretty here” according to Reid Wiseman

May 31 was a "nice day to hit the beach" in Santos, Brazil — May 31 was a “nice day to hit the beach” in Santos, Brazil

"Our planet is almost all ocean and so pretty," Tweeted Reid on June 1 — “Our planet is almost all ocean and so pretty,” Tweeted Reid on June 1

A "Soyuz selfie" in the cupola with Expedition 40/41 crew members Alexander Gerst, Oleg Artemyev, and Reid Wiseman, shared on June 2 — A “Soyuz group selfie” in the cupola with Expedition 40/41 crew members Alexander Gerst, Oleg Artemyev, and Reid Wiseman, shared on June 2

"Chile just left me speechless," Reid tweeted on June 4 — “Chile just left me speechless,” Reid tweeted on June 4

"Clouds turn 2D into 3D" tweeted Reid on Thursday, June 5 — “Clouds turn 2D into 3D” tweeted Reid on Thursday, June 5

Just a week into his stay aboard the ISS microgravity is already second nature!

See these photos (and more as they are taken!) on Reid Wiseman’s Twitter feed, and learn more about Expedition 40 here.

Photos courtesy Reid Wiseman/NASA.

May 21, 2014December 30, 2015 by Jason Major

ESA Marks 50 Years of Cooperative Space Innovation

Illustration of the ESA Planck Telescope in Earth orbit (Credit: ESA)

In 1964 the European Launcher Development Organisation (ELDO) and the European Space Research Organisation (ESRO) were founded, on February 29 and March 20 respectively, marking the beginning of Europe as a major space power and player in the new international venture to explore beyond our planet. A decade later these two entities merged to become ESA, and the rest, as it’s said, is history.

The video above commemorates ESA’s service to the cooperation and innovation of European nations in space, and indeed the entire world with many of the far-reaching exploration missions its member states have developed, launched and maintained. From advanced communications and observational satellites to its many missions exploring the worlds of the Solar System to capturing the light from the beginning of the Universe, ELDO, ESRO, and ESA have pushed the boundaries of science and technology in space for half a century… and are inspiring the next generation to continue exploring into the decades ahead. So happy anniversary, ESA — I can only imagine what we might be looking back on in another 50 years!

Source: ESA. See more key dates from ESA’s history here.

May 12, 2014December 28, 2015 by Fraser Cain

Astronomy Cast Ep. 345: Numbered Places: Launch Complex 39

Almost every historic American launch occurred at one place in Cape Canaveral: Launch Complex 39. Good old LC39 was build for the Apollo spacecraft, and then modified for the Space Shuttle program. And now it’s carrying on this tradition for upcoming SpaceX rockets. Let’s explore the history of this instrumental launch facility.
Continue reading “Astronomy Cast Ep. 345: Numbered Places: Launch Complex 39”

March 31, 2014December 28, 2015 by Fraser Cain

Astronomy Cast Ep. 341: 45th Lunar and Planetary Science Conference

Pamela has a day job, remember? As an astronomer? Recently the 45th Lunar and Planetary Science Conference occurred in the The Woodlands, Texas. Pamela and guest astronomer Sondy Springmann will let us know about the big announcements made at this year’s conference.?

Continue reading “Astronomy Cast Ep. 341: 45th Lunar and Planetary Science Conference”

March 28, 2014December 23, 2015 by Jason Major

ESA Awakens Rosetta’s Comet Lander

Artist's impression (not to scale) of the Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko. Credit: ESA–C. Carreau/ATG medialab.

Little Philae is awake! ESA sent a wake-up call to the 100-kg (220-lb) lander riding aboard the Rosetta spacecraft this morning at 06:00 GMT, bringing it out of its nearly 33-month-long slumber and beginning its preparation for its upcoming (and historic) landing on the surface of a comet in November.

Unlike Rosetta, which awoke in January via a pre-programmed signal, Philae received a “personal wake-up call” from Earth, 655 million kilometers away.

Hello, world! ESA's Rosetta and Philae comet explorers are now both awake and well! — Hello, world! ESA’s Rosetta and Philae comet explorers are now both awake and well!

A confirmation signal from the lander was received by ESA five and a half hours later at 11:35 GMT.

After over a decade of traveling across the inner Solar System, Rosetta and Philae are now in the home stretch of their ultimate mission: to orbit and achieve a soft landing on the inbound comet 67/P Churyumov-Gerasimenko. It will be the first time either feat has ever been attempted — and hopefully achieved — by a spacecraft.

After Rosetta maneuvers to meet up with the comet in May and actually enters orbit around it in August, it will search its surface for a good place for Philae to make its landing in November.

With a robotic investigator both on and around it, 67/P CG will reveal to us in intimate detail what a comet is made of and really happens to it as it makes its close approach to the Sun.

“Landing on the surface is the cherry on the icing on the cake for the Rosetta mission on top of all the great science that will be done by the orbiter in 2014 and 2015. A good chunk of this year will be spent identifying where we will land, but also taking vital measurements of the comet before it becomes highly active. No one has ever attempted this before and we are very excited about the challenge!”
– Matt Taylor, Rosetta project scientist

Meanwhile, today’s successful wake-up call let the Rosetta team know Philae is doing well. Further systems checks are planned for the lander throughout April.

Watch an animation of the deployment and landing of Philae on comet 67/P CG below:

Source: ESA’s Rosetta blog

Want to welcome Rosetta and Philae back on your computer? Download a series of ESA’s “Hello, World” desktop screens here.