This Cat Is So Cute

Extreme Science: Launching Sounding Rockets from The Arctic

This winter, our scientists and engineers traveled to the world’s northernmost civilian town to launch rockets equipped with cutting-edge scientific instruments.

This is the beginning of a 14-month-long campaign to study a particular region of Earth’s magnetic field — which means launching near the poles. What’s it like to launch a science rocket in these extreme conditions?

Our planet is protected by a natural magnetic field that deflects most of the particles that flow out from the Sun — the solar wind — away from our atmosphere. But near the north and south poles, two oddities in Earth’s magnetic field funnel these solar particles directly into our atmosphere. These regions are the polar cusps, and it turns out they’re the ideal spot for studying how our atmosphere interacts with space.

The scientists of the Grand Challenge Initiative — Cusp are using sounding rockets to do their research. Sounding rockets are suborbital rockets that launch to a few hundred miles in altitude, spending a few minutes in space before falling back to Earth. That means sounding rockets can carry sensitive instruments above our atmosphere to study the Sun, other stars and even distant galaxies.

They also fly directly through some of the most interesting regions of Earth’s atmosphere, and that’s what scientists are taking advantage of for their Grand Challenge experiments.

One of the ideal rocket ranges for cusp science is in Ny-Ålesund, Svalbard, off the coast of Norway and within the Arctic circle. Because of its far northward position, each morning Svalbard passes directly under Earth’s magnetic cusp.

But launching in this extreme, remote environment puts another set of challenges on the mission teams. These launches need to happen during the winter, when Svalbard experiences 24/7 darkness because of Earth’s axial tilt. The launch teams can go months without seeing the Sun.

Like for all rocket launches, the science teams have to wait for the right weather conditions to launch. Because they’re studying upper atmospheric processes, some of these teams also have to wait for other science conditions, like active auroras. Auroras are created when charged particles collide with Earth’s atmosphere — often triggered by solar storms or changes in the solar wind — and they’re related to many of the upper-atmospheric processes that scientists want to study near the magnetic cusp.

But even before launch, the extreme conditions make launching rockets a tricky business — it’s so cold that the rockets must be encased in styrofoam before launch to protect them from the low temperatures and potential precipitation.

When all is finally ready, an alarm sounds throughout the town of Ny-Ålesund to alert residents to the impending launch. And then it’s up, up and away! This photo shows the launch of the twin VISIONS-2 sounding rockets on Dec. 7, 2018 from Ny-Ålesund.

These rockets are designed to break up during flight — so after launch comes clean-up. The launch teams track where debris lands so that they can retrieve the pieces later.

The next launch of the Grand Challenge Initiative is AZURE, launching from Andøya Space Center in Norway in April 2019.

 For even more about what it’s like to launch science rockets in extreme conditions, check out one scientist’s notes from the field: https://go.nasa.gov/2QzyjR4

For updates on the Grand Challenge Initiative and other sounding rocket flights, visit nasa.gov/soundingrockets or follow along with NASA Wallops and NASA heliophysics on Twitter and Facebook.

@NASA_Wallops | NASA’s Wallops Flight Facility | @NASASun | NASA Sun Science

HiPOD (31 August 2018) Dunes in South Xainza Crater

   – They look so innocent… (270 km above the surface. Black and white is less than 5 km across; enhanced color is less than 1 km.)

NASA/JPL/University of Arizona

Greatest Hits — Craters We Love

Our solar system was built on impacts — some big, some small — some fast, some slow. This week, in honor of a possible newly-discovered large crater here on Earth, here’s a quick run through of some of the more intriguing impacts across our solar system.

1. Mercury: A Basin Bigger Than Texas

Mercury does not have a thick atmosphere to protect it from space debris. The small planet is riddled with craters, but none as spectacular as the Caloris Basin. “Basin” is what geologists call craters larger than about 186 miles (300 kilometers) in diameter. Caloris is about 950 miles (1,525 kilometers) across and is ringed by mile-high mountains.

For scale, the state of Texas is 773 miles (1,244 kilometers) wide from east to west.

2. Venus: Tough on Space Rocks

Venus’ ultra-thick atmosphere finishes off most meteors before they reach the surface. The planet’s volcanic history has erased many of its craters, but like almost any place with solid ground in our solar system, there are still impact scars to be found. Most of what we know of Venus’ craters comes from radar images provided by orbiting spacecraft, such as NASA’s Magellan.

Mead Crater is the largest known impact site on Venus. It is about 170 miles (275 kilometers) in diameter. The relatively-flat, brighter inner floor of the crater indicates it was filled with impact melt and/or lava.

3. Earth: Still Craters After All These Years

Evidence of really big impacts — such as Arizona’s Meteor Crater — are harder to find on Earth. The impact history of our home world has largely been erased by weather and water or buried under lava, rock or ice. Nonetheless, we still find new giant craters occasionally.

A NASA glaciologist has discovered a possible impact crater buried under more than a mile of ice in northwest Greenland.

This follows the finding, announced in November 2018, of a 19-mile (31-kilometer) wide crater beneath Hiawatha Glacier – the first meteorite impact crater ever discovered under Earth’s ice sheets. 

If the second crater, which has a width of over 22 miles (35 kilometers), is ultimately confirmed as the result of a meteorite impact, it will be the 22nd largest impact crater found on Earth.

4. Moon: Our Cratered Companion

Want to imagine what Earth might look like without its protective atmosphere, weather, water and other crater-erasing features? Look up at the Moon. The Moon’s pockmarked face offers what may be humanity’s most familiar view of impact craters.

One of the easiest to spot is Tycho, the tight circle and bright, radiating splat are easy slightly off center on the lower-left side of the full moon. Closer views of the 53-mile (85 kilometer)-wide crater from orbiting spacecraft reveal a beautiful central peak, topped with an intriguing boulder that would fill about half of a typical city block.

5. Mars: Still Taking Hits

Mars has just enough atmosphere to ensure nail-biting spacecraft landings, but not enough to prevent regular hits from falling space rocks. This dark splat on the Martian south pole is less than a year old, having formed between July and September 2018. The two-toned blast pattern tells a geologic story. The larger, lighter-colored blast pattern could be the result of scouring by winds from the impact shockwave on ice. The darker-colored inner blast pattern is because the impactor penetrated the thin ice layer, blasting the dark sand underneath in all directions.

6. Ceres: What Lies Beneath

The bright spots in Ceres’ Occator crater intrigued the world from the moment the approaching Dawn spacecraft first photographed it in 2015. Closer inspection from orbit revealed the spots to be the most visible example of hundreds of bright, salty deposits that decorate the dwarf planet like a smattering of diamonds. The science behind these bright spots is even more compelling: they are mainly sodium carbonate and ammonium chloride that somehow made their way to the surface in a slushy brine from within or below the crust. Thanks to Dawn, scientists have a better sense of how these reflective areas formed and changed over time — processes indicative of an active, evolving world.

7. Comet Tempel 1: We Did It!

Scientists have long known we can learn a lot from impact craters — so, in 2005, they made one themselves and watched it happen.

On July 4, 2005, NASA’s Deep Impact spacecraft trained its instruments on an 816-pound (370-kilogram) copper impactor as it smashed into comet Tempel 1.

One of the more surprising findings: The comet has a loose, “fluffy” structure, held together by gravity and contains a surprising amount of organic compounds that are part of the basic building blocks of life.

8. Mimas: May the 4th Be With You

Few Star Wars fans — us included — can resist Obi Wan Kenobi’s memorable line “That’s no moon…” when images of Saturn’s moon Mimas pop up on a screen. Despite its Death Star-like appearance, Mimas is most definitely a moon. Our Cassini spacecraft checked, a lot — and the superlaser-looking depression is simply an 81-mile (130-kilometer) wide crater named for the moon’s discoverer, William Herschel.

9. Europa: Say What?

The Welsh name of this crater on Jupiter’s ocean moon Europa looks like a tongue-twister, but it is easiest pronounced as “pool.” Pwyll is thought to be one of the youngest features we know of on Europa. The bright splat from the impact extends more than 600 miles (about 1,000 kilometers) around the crater, a fresh blanket over rugged, older terrain. “Fresh,” or young, is a relative term in geology; the crater and its rays are likely millions of years old.

10. Show Us Your Greatest Hits

Got a passion for Stickney, the dominant bowl-shaped crater on one end of Mars’ moon Phobos? Or a fondness for the sponge-like abundance of impacts on Saturn’s battered moon Hyperion (pictured)? There are countless craters to choose from. Share your favorites with us on Twitter, Instagram and Facebook.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

All Cats Are Beautiful

If the Moon were replaced with some of our planets (at night)

Image credit: yeti dynamics

What is a Wormhole?

Wormholes were first theorized in 1916, though that wasn’t what they were called at the time. While reviewing another physicist’s solution to the equations in Albert Einstein’s theory of general relativity, Austrian physicist Ludwig Flamm realized another solution was possible. He described a “white hole,” a theoretical time reversal of a black hole. Entrances to both black and white holes could be connected by a space-time conduit.

In 1935, Einstein and physicist Nathan Rosen used the theory of general relativity to elaborate on the idea, proposing the existence of “bridges” through space-time. These bridges connect two different points in space-time, theoretically creating a shortcut that could reduce travel time and distance. The shortcuts came to be called Einstein-Rosen bridges, or wormholes.

Certain solutions of general relativity allow for the existence of wormholes where the mouth of each is a black hole. However, a naturally occurring black hole, formed by the collapse of a dying star, does not by itself create a wormhole.

Wormholes are consistent with the general theory of relativity, but whether wormholes actually exist remains to be seen.

A wormhole could connect extremely long distances such as a billion light years or more, short distances such as a few meters, different universes, or different points in time

For a simplified notion of a wormhole, space can be visualized as a two-dimensional (2D) surface. In this case, a wormhole would appear as a hole in that surface, lead into a 3D tube (the inside surface of a cylinder), then re-emerge at another location on the 2D surface with a hole similar to the entrance. An actual wormhole would be analogous to this, but with the spatial dimensions raised by one. For example, instead of circular holes on a 2D plane, the entry and exit points could be visualized as spheres in 3D space.

Science fiction is filled with tales of traveling through wormholes. But the reality of such travel is more complicated, and not just because we’ve yet to spot one.

The first problem is size. Primordial wormholes are predicted to exist on microscopic levels, about 10–33 centimeters. However, as the universe expands, it is possible that some may have been stretched to larger sizes.

Another problem comes from stability. The predicted Einstein-Rosen wormholes would be useless for travel because they collapse quickly.

“You would need some very exotic type of matter in order to stabilize a wormhole,” said Hsu, “and it’s not clear whether such matter exists in the universe.”

But more recent research found that a wormhole containing “exotic” matter could stay open and unchanging for longer periods of time.

Exotic matter, which should not be confused with dark matter or antimatter, contains negative energy density and a large negative pressure. Such matter has only been seen in the behavior of certain vacuum states as part of quantum field theory.

If a wormhole contained sufficient exotic matter, whether naturally occurring or artificially added, it could theoretically be used as a method of sending information or travelers through space. Unfortunately, human journeys through the space tunnels may be challenging.

Wormholes may not only connect two separate regions within the universe, they could also connect two different universes. Similarly, some scientists have conjectured that if one mouth of a wormhole is moved in a specific manner, it could allow for time travel.

Although adding exotic matter to a wormhole might stabilize it to the point that human passengers could travel safely through it, there is still the possibility that the addition of “regular” matter would be sufficient to destabilize the portal.

Today’s technology is insufficient to enlarge or stabilize wormholes, even if they could be found. However, scientists continue to explore the concept as a method of space travel with the hope that technology will eventually be able to utilize them.

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Unusual Signal Suggests Neutron Star Destroyed by Black Hole

What created this unusual explosion? Three weeks ago, gravitational wave detectors in the USA and Europe – the LIGO and Virgo detectors – detected a burst of gravitational radiation that had the oscillating pattern expected when a black hole destroys a neutron star. One object in event S190814sv was best fit with a mass greater than five times the mass of the Sun – making it a good candidate for a black hole, while the other object appeared to have a mass less than three times the mass of the Sun – making it a good candidate for a neutron star. No similar event had been detected with gravitational waves before. Unfortunately, no light was seen from this explosion, light that might have been triggered by the disrupting neutron star. It is theoretically possible that the lower mass object was also a black hole, even though no clear example of a black hole with such a low mass is known. The featured video was created to illustrate a previously suspected black hole - neutron star collision detected in light in 2005, specifically gamma-rays from the burst GRB 050724. The animated video starts with a foreground neutron star orbiting a black hole surrounded by an accretion disk. The black hole’s gravity then shreds the neutron star, creating a jet as debris falls into the black hole. S190814sv will continue to be researched, with clues about the nature of the objects involved possibly coming from future detections of similar systems. Illustration Video Credit: NASA, Dana Berry (Skyworks Digital)

Will we one day explore the worlds of our solar system? How long will this take?

We have a diversity of worlds in our solar system. Majestic places…

Imagine being able to visit Mars and its hostile climate. Imagine being able to visit the moons of Jupiter, observe Io: the volcanic moon, Europa, the frozen moon and Ganymede a moon larger than Mercury itself and that has its own magnetic field. Imagine visiting the moons of Saturn and maybe passing close to your rings… Imagine orbiting or floating through Titan’s atmosphere and closely watching its lakes and seas of methane and liquid ethane. Imagine getting to know the geysers of Enceladus, the valleys of Tethys, and the craters of Mimas… Imagine being able to see the moons of Uranus and have a view of Verona Rupes, the largest cliff of the solar system, located in Miranda. Imagine being able to be in Triton and to be able to observe the cold and azualdo Neptune in the sky…

The Scorpii AR system

In the system AR Scorpii a rapidly spinning white dwarf star powers electrons up to almost the speed of light. These high energy particles release blasts of radiation that lash the companion red dwarf star, and cause the entire system to pulse dramatically every 1.97 minutes with radiation ranging from the ultraviolet to radio.

The star system AR Scorpii, or AR Sco for short, lies in the constellation of Scorpius, 380 light-years from Earth. It comprises a rapidly spinning white dwarf, the size of Earth but containing 200,000 times more mass, and a cool red dwarf companion one third the mass of the Sun, orbiting one another every 3.6 hours in a cosmic dance as regular as clockwork.

Read more at: cosmosmagazine & astronomynow