SHIELDS Up! NASA Rocket To Survey Our Solar System’s Windshield Apr 16, 2021
SHIELDS Up! NASA Rocket to Survey Our Solar System’s Windshield Apr 16, 2021
Eleven billion miles away – more than four times the distance from us to Pluto – lies the boundary of our solar system’s magnetic bubble, the heliopause. Here the Sun’s magnetic field, stretching through space like an invisible cobweb, fizzles to nothing. Interstellar space begins. “It’s really the largest boundary of its kind we can study,” said Walt Harris, space physicist at the University of Arizona in Tucson.
We still know little about what lies beyond this boundary. Fortunately, bits of interstellar space can come to us, passing right through this border and making their way into the solar system.
A new NASA mission will study light from interstellar particles that have drifted into our solar system to learn about the closest reaches of interstellar space. The mission, called the Spatial Heterodyne Interferometric Emission Line Dynamics Spectrometer, or SHIELDS, will have its first opportunity to launch aboard a suborbital rocket from the White Sands Missile Range in New Mexico on April 19, 2021.
Our entire solar system is adrift in a cluster of clouds, an area cleared by ancient supernova blasts. Astronomers call this region the Local Bubble, an oblong plot of space about 300 light-years long within the spiraling Orion arm of our Milky Way galaxy. It contains hundreds of stars, including our own Sun.
We fare this interstellar sea is our trusty vessel, the heliosphere, a much smaller (though still gigantic) magnetic bubble blown up by the Sun. As we orbit the Sun, the solar system itself, encased in the heliosphere, hurtles through the Local Bubble at about 52,000 miles per hour (23 kilometers per second). Interstellar particles pelt the nose of our heliosphere like rain against a windshield.
Our heliosphere is more like a rubber raft than a wooden sailboat: Its surroundings mold its shape. It compresses at points of pressure, expands where it gives way. Exactly how and where our heliosphere’s lining deforms gives us clues about the nature of the interstellar space outside it. This boundary – and any deformities in it – are what Walt Harris, principal investigator for the SHIELDS mission, is after.
SHIELDS is a telescope that will launch aboard a sounding rocket, a small vehicle that flies to space for a few minutes of observing time before falling back to Earth. Harris’ team launched an earlier iteration of the telescope as part of the HYPE mission in 2014, and after modifying the design, they’re ready to launch again.
SHIELDS will measure light from a special population of hydrogen atoms originally from interstellar space. These atoms are neutral, with a balanced number of protons and electrons. Neutral atoms can cross magnetic field lines, so they seep through the heliopause and into our solar system nearly unfazed – but not completely.
The small effects of this boundary crossing are key to SHIELDS’s technique. Charged particles flow around the heliopause, forming a barrier. Neutral particles from interstellar space must pass through this gauntlet, which alters their paths. SHIELDS was designed to reconstruct the trajectories of the neutral particles to determine where they came from and what they saw along the way.
A few minutes after launch, SHIELDS will reach its peak altitude of about 186 miles (300 kilometers) from the ground, far above the absorbing effect of Earth’s atmosphere. Pointing its telescope towards the nose of the heliosphere, it will detect light from arriving hydrogen atoms. Measuring how that light’s wavelength stretches or contracts reveals the particles’ speed. All told, SHIELDS will produce a map to reconstruct the shape and varying density of matter at the heliopause.
The data, Harris hopes, will help answer tantalizing questions about what interstellar space is like.
For instance, astronomers think the Local Bubble as a whole is about 1/10th as dense as most of the rest of the galaxy’s main disk. But we don’t know the details – for instance, is matter in the Local Bubble is distributed evenly, or bunched up in dense pockets surrounded by nothingness? “There’s a lot of uncertainty about the fine structure of the interstellar medium – our maps are kind of crude,” Harris said. “We know the general outlines of these clouds, but we don’t know what’s happening inside them.”
Astronomers also don’t know much about the galaxy’s magnetic field. But it should leave a mark on our heliosphere that SHIELDS can detect, compressing the heliopause in a specific way based on its strength and orientation.
Finally, learning what our current plot of interstellar space is like could be a helpful guide for the (distant) future. Our solar system is just passing through our current patch of space. In some 50,000 years, we’ll be on our way out of the Local Bubble and on to who knows what.
“We don’t really know what that other cloud is like, and we don’t know what happens when you cross a boundary into that cloud,” Harris said. “There’s a lot of interest in understanding what we’re likely to experience as our solar system makes that transition.”
Not that our solar system hasn’t done it before. Over the last four billion years, Harris explains, Earth has passed through a variety of interstellar environments. It’s just that now we’re around, with the scientific tools to document it.
“We’re just trying to understand our place in the galaxy, and where we’re headed in the future,” Harris said.
TOP IMAGE….An illustration of the heliosphere being pelted with cosmic rays from outside our solar system. Credit: NASA’s Goddard Space Flight Center/Conceptual Image Lab
LOWER IMAGE….Illustration of the Local Bubble. Credits: NASA’s Goddard Space Flight Center
More Posts from Science-child and Others
When Dead Stars Collide!
Gravity has been making waves - literally. Earlier this month, the Nobel Prize in Physics was awarded for the first direct detection of gravitational waves two years ago. But astronomers just announced another huge advance in the field of gravitational waves - for the first time, we’ve observed light and gravitational waves from the same source.
There was a pair of orbiting neutron stars in a galaxy (called NGC 4993). Neutron stars are the crushed leftover cores of massive stars (stars more than 8 times the mass of our sun) that long ago exploded as supernovas. There are many such pairs of binaries in this galaxy, and in all the galaxies we can see, but something special was about to happen to this particular pair.
Each time these neutron stars orbited, they would lose a teeny bit of gravitational energy to gravitational waves. Gravitational waves are disturbances in space-time - the very fabric of the universe - that travel at the speed of light. The waves are emitted by any mass that is changing speed or direction, like this pair of orbiting neutron stars. However, the gravitational waves are very faint unless the neutron stars are very close and orbiting around each other very fast.
As luck would have it, the teeny energy loss caused the two neutron stars to get a teeny bit closer to each other and orbit a teeny bit faster. After hundreds of millions of years, all those teeny bits added up, and the neutron stars were *very* close. So close that … BOOM! … they collided. And we witnessed it on Earth on August 17, 2017.
Credit: National Science Foundation/LIGO/Sonoma State University/A. Simonnet
A couple of very cool things happened in that collision - and we expect they happen in all such neutron star collisions. Just before the neutron stars collided, the gravitational waves were strong enough and at just the right frequency that the National Science Foundation (NSF)’s Laser Interferometer Gravitational-Wave Observatory (LIGO) and European Gravitational Observatory’s Virgo could detect them. Just after the collision, those waves quickly faded out because there are no longer two things orbiting around each other!
LIGO is a ground-based detector waiting for gravitational waves to pass through its facilities on Earth. When it is active, it can detect them from almost anywhere in space.
The other thing that happened was what we call a gamma-ray burst. When they get very close, the neutron stars break apart and create a spectacular, but short, explosion. For a couple of seconds, our Fermi Gamma-ray Telescope saw gamma-rays from that explosion. Fermi’s Gamma-ray Burst Monitor is one of our eyes on the sky, looking out for such bursts of gamma-rays that scientists want to catch as soon as they’re happening.
And those gamma-rays came just 1.7 seconds after the gravitational wave signal. The galaxy this occurred in is 130 million light-years away, so the light and gravitational waves were traveling for 130 million years before we detected them.
After that initial burst of gamma-rays, the debris from the explosion continued to glow, fading as it expanded outward. Our Swift, Hubble, Chandra and Spitzer telescopes, along with a number of ground-based observers, were poised to look at this afterglow from the explosion in ultraviolet, optical, X-ray and infrared light. Such coordination between satellites is something that we’ve been doing with our international partners for decades, so we catch events like this one as quickly as possible and in as many wavelengths as possible.
Astronomers have thought that neutron star mergers were the cause of one type of gamma-ray burst - a short gamma-ray burst, like the one they observed on August 17. It wasn’t until we could combine the data from our satellites with the information from LIGO/Virgo that we could confirm this directly.
This event begins a new chapter in astronomy. For centuries, light was the only way we could learn about our universe. Now, we’ve opened up a whole new window into the study of neutron stars and black holes. This means we can see things we could not detect before.
The first LIGO detection was of a pair of merging black holes. Mergers like that may be happening as often as once a month across the universe, but they do not produce much light because there’s little to nothing left around the black hole to emit light. In that case, gravitational waves were the only way to detect the merger.
Image Credit: LIGO/Caltech/MIT/Sonoma State (Aurore Simonnet)
The neutron star merger, though, has plenty of material to emit light. By combining different kinds of light with gravitational waves, we are learning how matter behaves in the most extreme environments. We are learning more about how the gravitational wave information fits with what we already know from light - and in the process we’re solving some long-standing mysteries!
Want to know more? Get more information HERE.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
“If you read the history of the development of chemistry and particularly of physics, you will see that even such exact natural sciences could not, and still cannot, avoid basing their thought systems on certain hypotheses. In classical physics, up to the end of the 18th century, one of the working hypotheses, arrived at either unconsciously or half-consciously, was that space had three dimensions, an idea which was never questioned. The fact was always accepted, and perspective drawings of physical events, diagrams, or experiments, were always in accordance with that theory. Only when this theory is abandoned does one wonder how such a thing could ever have been believed. How did one come by such an idea? Why were we so caught that nobody ever doubted or even discussed the matter? It was accepted as a self-evident fact, but what was at the root of it? Johannes Kepler, one of the fathers of modern or classic physics, said that naturally space must have three dimensions because of the Trinity! So our readiness to believe that space has three dimensions is a more recent offspring of the Christian trinitarian idea.”
— Marie-Louise von Franz, Alchemy: An Introduction to the Symbolism and the Psychology
Our universe is FULL of strange and surprising things.
And luckily, our Hubble Space Telescope is there to be our window to the unimaginable! Hubble recently ran into an issue with its payload computer which controls and coordinates science instruments onboard the spacecraft. On July 16, teams successfully switched to backup hardware to compensate for the problem! A day later, the telescope resumed normal science operations. To celebrate, we’re taking you back to 2016 when our dear Hubble captured perhaps one of the most intriguing objects in our Milky Way galaxy: a massive star trapped inside a bubble! The star inside this Bubble Nebula burns a million times brighter than our Sun and produces powerful gaseous outflows that howl at more than four million miles per hour. Based on the rate the star is expending energy, scientists estimate in 10 to 20 million years it will explode as a supernova. And the bubble will succumb to a common fate: It’ll pop.
Do you believe in magic? ✨ While appearing as a delicate and light veil draped across the sky, this @NASAHubble image reminds us of the power of imagination. What does this look like to you? In reality, it’s a small section of a Cygnus supernova blast wave, located around 2,400 light-years away. The original supernova explosion blasted apart a dying star about 20 times more massive than our Sun between 10,000 and 20,000 years ago. Since then, the remnant has expanded 60 light-years from its center. Credit: @ESA/Hubble & NASA, W. Blair; acknowledgment: Leo Shatz
That's true with stars. We can never see stars or planets in the 'now' bc it took the light we are seeing time to get to us.
Even the sunlight takes 8 minutes to travel from the sun to earth, so if the sun exploded, we wouldn't know for 8 minutes.
In 2015, LIGO detected some gravitational waves from something that happened 1.3 billion years ago, in the constellation, Hydra. If you were on Hydra looking at Earth rn, you'd be seeing Earth from 1.3 billion years ago. 1.3 billion years ago, we were in the Mesoproterozoic Era here on earth. Life was just beginning to develop into multi-cellular organisms.
In conclusion: yes
wait i was in a tiktok comment section for something abt space and im no scientist obviously, but what if the reason we haven't found proof of life in space yet is because light takes time to travel from there to earth. like we arent seeing what's currently happening up there just what was happening way in the past.
That's a wrap! Thank you all for the wonderful questions.
NASA Mars Perseverance Rover Mission Engineer Chloe Sackier answered questions about how we prepared for the mission, Perseverance’s entry, descent, and landing, and what Perseverance will do once on Mars.
Check out her full Answer Time for more: Career | Preparation | Entry, Descent, & Landing | Operation
We hope you had fun today and learned a little bit about our robotic astrobiologist landing on Mars on February 18th. You won't want to miss this! Tune in to NASA TV HERE starting at 2:15 p.m. EST.
If today’s Answer Time got you excited, team up with us to #CoutdownToMars! We created a virtual Mars photo booth, have sounds of Mars to listen to and more for all you Earthlings to channel your inner Martian. Check out ways to participate HERE.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
"Equipped with his five senses, man explores the universe around him and calls the adventure science."
-Edwin P. Hubble
Taking Solar Science to New Heights
We’re on the verge of launching a new spacecraft to the Sun to take the first-ever images of the Sun’s north and south poles!
Credit: ESA/ATG medialab
Solar Orbiter is a collaboration between the European Space Agency (ESA) and NASA. After it launches — as soon as Feb. 9 — it will use Earth’s and Venus’s gravity to swing itself out of the ecliptic plane — the swath of space, roughly aligned with the Sun’s equator, where all the planets orbit. From there, Solar Orbiter’s bird’s eye view will give it the first-ever look at the Sun’s poles.
Credit: ESA/ATG medialab
The Sun plays a central role in shaping space around us. Its massive magnetic field stretches far beyond Pluto, paving a superhighway for charged solar particles known as the solar wind. When bursts of solar wind hit Earth, they can spark space weather storms that interfere with our GPS and communications satellites — at their worst, they can even threaten astronauts.
To prepare for potential solar storms, scientists monitor the Sun’s magnetic field. But from our perspective near Earth and from other satellites roughly aligned with Earth’s orbit, we can only see a sidelong view of the Sun’s poles. It’s a bit like trying to study Mount Everest’s summit from the base of the mountain.
Solar Orbiter will study the Sun’s magnetic field at the poles using a combination of in situ instruments — which study the environment right around the spacecraft — and cameras that look at the Sun, its atmosphere and outflowing material in different types of light. Scientists hope this new view will help us understand not only the Sun’s day-to-day activity, but also its roughly 11-year activity cycles, thought to be tied to large-scales changes in the Sun’s magnetic field.
Solar Orbiter will fly within the orbit of Mercury — closer to our star than any Sun-facing cameras have ever gone — so the spacecraft relies on cutting-edge technology to beat the heat.
Credit: ESA/ATG medialab
Solar Orbiter has a custom-designed titanium heat shield with a calcium phosphate coating that withstands temperatures more than 900 degrees Fahrenheit — 13 times the solar heating that spacecraft face in Earth orbit. Five of the cameras look at the Sun through peepholes in that heat shield; one observes the solar wind out the side.
Over the mission’s seven-year lifetime, Solar Orbiter will reach an inclination of 24 degrees above the Sun’s equator, increasing to 33 degrees with an additional three years of extended mission operations. At closest approach the spacecraft will pass within 26 million miles of the Sun.
Solar Orbiter will be our second major mission to the inner solar system in recent years, following on August 2018’s launch of Parker Solar Probe. Parker has completed four close solar passes and will fly within 4 million miles of the Sun at closest approach.
Solar Orbiter (green) and Parker Solar Probe (blue) will study the Sun in tandem.
The two spacecraft will work together: As Parker samples solar particles up close, Solar Orbiter will capture imagery from farther away, contextualizing the observations. The two spacecraft will also occasionally align to measure the same magnetic field lines or streams of solar wind at different times.
Watch the launch
The booster of a United Launch Alliance Atlas V rocket that will launch the Solar Orbiter spacecraft is lifted into the vertical position at the Vertical Integration Facility near Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida on Jan. 6, 2020. Credit: NASA/Ben Smegelsky
Solar Orbiter is scheduled to launch on Feb. 9, 2020, during a two-hour window that opens at 11:03 p.m. EST. The spacecraft will launch on a United Launch Alliance Atlas V 411 rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida.
Launch coverage begins at 10:30 p.m. EST on Feb. 9 at nasa.gov/live. Stay up to date with mission at nasa.gov/solarorbiter!
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
Are You Up to the Task of Navigating Space with NASA?
We’re committed to exploration and discovery, journeying to the Moon, Mars, and beyond. But how do we guide our missions on their voyage among the stars? Navigation engineers lead the way!
Using complex mathematical formulas, navigation experts calculate where our spacecraft are and where they’re headed. No matter the destination, navigating the stars is a complicated challenge that faces all our missions. But, we think you’re up to the task!
Our space navigation workbook lets you explore the techniques and mathematical concepts used by navigation engineers. The book delves into groundbreaking navigation innovations like miniaturized atomic clocks, autonomous navigation technologies, using GPS signals at the Moon, and guiding missions through the solar system with X-ray emissions from pulsars — a type of neutron star. It also introduces you to experts working with NASA’s Space Communications and Navigation program at Goddard Space Flight Center in Greenbelt, Maryland.
If you’re a high schooler who dreams of guiding a rover across the rocky surface of Mars or planning the trajectory of an observer swinging around Venus en route to the Sun, this workbook is for you! Download it today and start your adventure with NASA: https://go.nasa.gov/3i7Pzqr
-
se-mats liked this · 4 years ago -
science-child reblogged this · 4 years ago -
awxward liked this · 4 years ago -
spacetimewithstuartgary reblogged this · 4 years ago
