What Makes Something A Planet, According To An Astrophysicist?

10 Things: CubeSats — Going Farther

Now that the MarCOs — a pair of briefcase-sized interplanetary CubeSats — seem to have reached their limit far beyond Mars, we’re looking forward to an expanding era of small, versatile and powerful space-based science machines.

Here are ten ways we’re pushing the limits of miniaturized technology to see  just how far it can take us.

1. MarCO: The Farthest (So Far)

MarCO, short for Mars Cube One, was the first interplanetary mission to use a class of mini-spacecraft called CubeSats.

The MarCOs — nicknamed EVE and WALL-E, after characters from a Pixar film — served as communications relays during InSight’s November 2018 Mars landing, beaming back data at each stage of its descent to the Martian surface in near-real time, along with InSight’s first image.

WALL-E sent back stunning images of Mars as well, while EVE performed some simple radio science.

All of this was achieved with experimental technology that cost a fraction of what most space missions do: $18.5 million provided by NASA’s Jet Propulsion Laboratory in Pasadena, California, which built the CubeSats.

WALL-E was last heard from on Dec. 29; EVE, on Jan. 4. Based on trajectory calculations, WALL-E is currently more than 1 million miles (1.6 million kilometers) past Mars; EVE is farther, almost 2 million miles (3.2 million kilometers) past Mars.

MarCO-B took these images as it approached Mars in November 2018. Credit: NASA/JPL-Caltech

2. What Are CubeSats?

CubeSats were pioneered by California Polytechnic State University in 1999 and quickly became popular tools for students seeking to learn all aspects of spacecraft design and development.

Today, they are opening up space research to public and private entities like never before. With off-the-shelf parts and a compact size that allows them to hitch a ride with other missions — they can, for example, be ejected from the International Space Station, up to six at a time — CubeSats have slashed the cost of satellite development, opening up doors to test new instruments as well as to create constellations of satellites working together.

CubeSats can be flown in swarms, capturing simultaneous, multipoint measurements with identical instruments across a large area. Sampling entire physical systems in this way would drive forward our ability to understand the space environment around us, in the same way multiple weather sensors help us understand global weather systems.

Ready to get started? Check out NASA’s CubeSats 101 Guide.

Engineer Joel Steinkraus uses sunlight to test the solar arrays on one of the Mars Cube One (MarCO) spacecraft at NASA’s Jet Propulsion Laboratory. Credit: NASA/JPL-Caltech

3. Measuring Up

The size and cost of spacecraft vary depending on the application; some are the size of a pint of ice cream while others, like the Hubble Space Telescope, are as big as a school bus.

Small spacecraft (SmallSats) generally have a mass less than 400 pounds (180 kilograms) and are about the size of a large kitchen fridge.

CubeSats are a class of nanosatellites that use a standard size and form factor.  The standard CubeSat size uses a “one unit” or “1U” measuring 10x10x10 centimeters (or about 4x4x4 inches) and is extendable to larger sizes: 1.5, 2, 3, 6, and even 12U.

The Sojourner rover (seen here on Mars in 1997) is an example of small technology that pioneered bigger things. Generations of larger rovers are being built on its success.

4. A Legacy of Small Pathfinders

Not unlike a CubeSat, NASA’s first spacecraft — Explorer 1 — was a small, rudimentary machine. It launched in 1958 and made the first discovery in outer space, the Van Allen radiation belts that surround Earth. It was the birth of the U.S. space program.

In 1997, a mini-rover named Sojourner rolled onto Mars, a trial run for more advanced rovers such as NASA’s Spirit, Opportunity and Curiosity.

Innovation often begins with pathfinder technology, said Jakob Van Zyl, director of the Solar System Exploration Directorate at NASA’s Jet Propulsion Laboratory. Once engineers prove something can be done, science missions follow.

5. Testing in Space

NASA is continually developing new technologies — technologies that are smaller than ever before, components that could improve our measurements, on-board data processing systems that streamline data retrievals, or new methods for gathering observations. Each new technology is thoroughly tested in a lab, sometimes on aircraft, or even at remote sites across the world. But the space environment is different than Earth. To know how something is going to operate in space, testing in space is the best option.

Sending something unproven to orbit has traditionally been a risky endeavor, but CubeSats have helped to change that. The diminutive satellites typically take less than two years to build. CubeSats are often a secondary payload on many rocket launches, greatly reducing cost. These hitchhikers can be deployed from a rocket or sent to the International Space Station and deployed from orbit.

Because of their quick development time and easy access to space, CubeSats have become the perfect platform for demonstrating how a new technological advancement will perform in orbit.

RainCube is a mini weather satellite, no bigger than a shoebox, that will measure storms. It’s part of several new NASA experiments to track storms from space with many small satellites, instead of individual, large ones. Credit: UCAR

6. At Work in Earth Orbit

A few recent examples from our home world:

RainCube, a satellite no bigger than a suitcase, is a prototype for a possible fleet of similar CubeSats  that could one day help monitor severe storms, lead to improving the accuracy of weather forecasts and track climate change over time.

IceCube tested instruments for their ability to make space-based measurements of the small, frozen crystals that make up ice clouds. Like other clouds, ice clouds affect Earth’s energy budget by either reflecting or absorbing the Sun’s energy and by affecting the emission of heat from Earth into space. Thus, ice clouds are key variables in weather and climate models.

Rocket Lab’s Electron rocket lifts off from Launch Complex 1 for the NASA ELaNa19 mission. Credit: Trevor Mahlmann/Rocket Lab

7. First Dedicated CubeSat Launch

A series of new CubeSats is now in space, conducting a variety of scientific investigations and technology demonstrations following a Dec. 17, 2018 launch from New Zealand — the first time CubeSats have launched for NASA on a rocket designed specifically for small payloads.

This mission included 10 Educational Launch of Nanosatellites (ELaNa)-19 payloads, selected by NASA’s CubeSat Launch Initiative:

CubeSat Compact Radiation Belt Explorer (CeREs) — High energy particle measurement in Earth’s radiation belt

Simulation-to-Flight 1 (STF-1) — Software condensing to support CubeSat implementations

Advanced Electrical Bus (ALBus) — Advances in solar arrays and high capacity batteries

CubeSat Handling Of Multisystem Precision Time Transfer (CHOMPTT) — Navigation plans for exo-planetary implementation

CubeSail — Deployment and control of a solar sail blade

NMTSat — Magnetic field, high altitude plasma density

Rsat — Manipulation of robotic arms

Ionospheric Scintillation Explorer (ISX) — Plasma fluctuations in the upper atmosphere

Shields-1 — Radiation shielding

DaVinci — High School to Grade School STEM education

8. The Little CubeSat That Could

CubeSat technology is still in its infancy, with mission success rates hovering near 50 percent. So, a team of scientists and engineers set out on a quest. Their goal? To build a more resilient CubeSat — one that could handle the inevitable mishaps that bedevil any spacecraft, without going kaput.

They wanted a little CubeSat that could.

They got to work in 2014 and, after three years of development, Dellingr was ready to take flight.

Read the Full Story: Dellingr: The Little CubeSat That Could

Artist’s concept of Lunar Flashlight. Credit: NASA

9. Going Farther

There are a handful of proposed NASA missions could take CubeSat technology farther:

CUVE would travel to Venus to investigate a longstanding mystery about the planet’s atmosphere using ultraviolet-sensitive instruments and a novel, carbon-nanotube light-gathering mirror.

Lunar Flashlight would use a laser to search for water ice in permanently shadowed craters on the south pole of Earth’s Moon.

Near-Earth Asteroid Scout, a SmallSat, would use a solar sail to propel it to do science on asteroids that pass close to Earth.

All three spacecraft would hitch rides to space with other missions, a key advantage of these compact science machines.

Expedition 56 Flight Engineer Serena Auñón-Chancellor installs the NanoRacks Cubesat Deployer-14 (NRCSD-14) on the Multipurpose Experiment Platform inside the Japanese Kibo laboratory module. The NRCSD-14 was then placed in the Kibo airlock and moved outside of the space station to deploy a variety of CubeSats into Earth orbit. Credit: NASA

10. And We’re Just Getting Started

Even if they’re never revived, the team considers MarCO a spectacular success.

A number of the critical spare parts for each MarCO will be used in other CubeSat missions. That includes their experimental radios, antennas and propulsion systems. Several of these systems were provided by commercial vendors, making it easier for other CubeSats to use them as well.

More small spacecraft are on the way. NASA is set to launch a variety of new CubeSats in coming years.

“There’s big potential in these small packages,” said John Baker, the MarCO program manager at JPL. “CubeSats — part of a larger group of spacecraft called SmallSats — are a new platform for space exploration affordable to more than just government agencies.”

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Ask Ethan: Is Spacetime Really A Fabric?

“I’d like somebody to finally acknowledge and admit that showing balls on a bed sheet doesn’t cut it as a picture of reality.”

Okay, I admit it: visualizing General Relativity as balls on a bedsheet doesn’t make a whole lot of sense. For one, if this is what gravity is supposed to be, what pulls the balls “down” onto the bedsheet? For another, if space is three dimensional, why are we talking about a 2D “fabric” of space? And for another, why do these lines curve away from the mass, rather than towards it?

It’s true: this visualization of General Relativity is highly flawed. But, believe it or not, all visualizations of General Relativity inherently have similar flaws. The reason is that space itself is not an observable thing! In Einstein’s theory, General Relativity provides the link between the matter and energy in the Universe, which determines the geometric curvature of spacetime, and how the rest of the matter and energy in the Universe moves in response to that. In this Universe, we can only measure matter and energy, not space itself. We can visualize it how we like, but all visualizations are inherently flawed.

Come get the story of how to make as much sense as possible out of the Universe we actually have.

Couple goals

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I was wondering if you could go in depth, at least to a degree about how incredibly dense objects have strong enough gravity to distort light. To me that's one of the wildest concepts I can imagine, not that I expect you to be all knowing but maybe you've got a good article or something? I don't recall if you've ever made posts about the theory of relativity. Sorry for the long ask!

Well, I know only the basics, things I study in my free time, however, I can try to explain. The distortion of space-time is described by Einstein’s Theory of General Reality. The more massive an object, the more its curvature will be in the space-time fabric.

This distortion in light is known as a gravitational lensing. The gravitational lensing is formed due to a space-time distortion caused by the presence of a large mass body between a distant light source and an observer.

These distortions are widely observed through globular clusters.

Since the amount of lensing depends on the total mass of the cluster, gravitational lensing can be used to ‘weigh’ clusters. This has considerably improved our understanding of the distribution of the ‘hidden’ dark matter in galaxy clusters and hence in the Universe as a whole. The effect of gravitational lensing also allowed a first step towards revealing the mystery of the dark energy.

As gravitational lenses function as magnification glasses it is possible to use them to study distant galaxies from the early Universe, which otherwise would be impossible to see.

Gravitational lensing happens on all scales – the gravitational field of galaxies and clusters of galaxies can lens light, but so can smaller objects such as stars and planets. Even the mass of our own bodies will lens light passing near us a tiny bit, although the effect is too small to ever measure.

Using All of Our Senses in Space

Today, we and the National Science Foundation (NSF) announced the detection of light and a high-energy cosmic particle that both came from near a black hole billions of trillions of miles from Earth. This discovery is a big step forward in the field of multimessenger astronomy.

But wait — what is multimessenger astronomy? And why is it a big deal?

People learn about different objects through their senses: sight, touch, taste, hearing and smell. Similarly, multimessenger astronomy allows us to study the same astronomical object or event through a variety of “messengers,” which include light of all wavelengths, cosmic ray particles, gravitational waves, and neutrinos — speedy tiny particles that weigh almost nothing and rarely interact with anything. By receiving and combining different pieces of information from these different messengers, we can learn much more about these objects and events than we would from just one.

Lights, Detector, Action!  

Much of what we know about the universe comes just from different wavelengths of light. We study the rotations of galaxies through radio waves and visible light, investigate the eating habits of black holes through X-rays and gamma rays, and peer into dusty star-forming regions through infrared light.

The Fermi Gamma-ray Space Telescope, which recently turned 10, studies the universe by detecting gamma rays — the highest-energy form of light. This allows us to investigate some of the most extreme objects in the universe.

Last fall, Fermi was involved in another multimessenger finding — the very first detection of light and gravitational waves from the same source, two merging neutron stars. In that instance, light and gravitational waves were the messengers that gave us a better understanding of the neutron stars and their explosive merger into a black hole.

Fermi has also advanced our understanding of blazars, which are galaxies with supermassive black holes at their centers. Black holes are famous for drawing material into them. But with blazars, some material near the black hole shoots outward in a pair of fast-moving jets. With blazars, one of those jets points directly at us!

Multimessenger Astronomy is Cool

Today’s announcement combines another pair of messengers. The IceCube Neutrino Observatory lies a mile under the ice in Antarctica and uses the ice itself to detect neutrinos. When IceCube caught a super-high-energy neutrino and traced its origin to a specific area of the sky, they alerted the astronomical community.

Fermi completes a scan of the entire sky about every three hours, monitoring thousands of blazars among all the bright gamma-ray sources it sees. For months it had observed a blazar producing more gamma rays than usual. Flaring is a common characteristic in blazars, so this did not attract special attention. But when the alert from IceCube came through about a neutrino coming from that same patch of sky, and the Fermi data were analyzed, this flare became a big deal!

IceCube, Fermi, and followup observations all link this neutrino to a blazar called TXS 0506+056. This event connects a neutrino to a supermassive black hole for the very first time.  

Why is this such a big deal? And why haven’t we done it before? Detecting a neutrino is hard since it doesn’t interact easily with matter and can travel unaffected great distances through the universe. Neutrinos are passing through you right now and you can’t even feel a thing!

The neat thing about this discovery — and multimessenger astronomy in general — is how much more we can learn by combining observations. This blazar/neutrino connection, for example, tells us that it was protons being accelerated by the blazar’s jet. Our study of blazars, neutrinos, and other objects and events in the universe will continue with many more exciting multimessenger discoveries to come in the future.

Want to know more? Read the story HERE.

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Here’s Why Black Holes Are Crullers, Not Donuts

“Just a few years ago, we didn’t even know whether it was a certainty that black holes had an event horizon, as we’d never observed one directly. In 2017, a series of observations were finally taken that could settle the issue. After a wait of two years, the first direct image of a black hole was released, and it showed us that the event horizon was, in fact, real as predicted, and that its properties agreed with Einstein’s predictions.

Now, another two years later, the polarization data has been added into the fold, and we can now reconstruct the magnetic properties of the plasma surrounding the black hole, along with how those features are imprinted onto the emitted photons. We still only have the one black hole that’s been directly imaged, but we can see how the light, the polarization, and the magnetic properties of the plasma surrounding the event horizon all change over time.”

You’ve seen the photo, but have you learned the science? Black holes are crullers, not donuts, and magnetized plasma is the reason why.

The Planets and their respective sizes compared to our Sun.