Stefano Coledan
Mon, August 14, 2023
NASA's Psyche satellite sits at the Astrotech Space Operations Facility in Titusville, Fla., not far from Kennedy Space Center in Florida on Friday. The spacecraft is being prepared for launch Oct. 5 and will fly on a six-year journey to explore the metal rich 16 Psyche asteroid. Photo by Joe Marino/UPI
CAPE CANAVERAL, Fla., Aug. 14 (UPI) -- Preparations are proceeding for the early October launch of a NASA orbiter that uses futuristic electric propulsion technology for a rendezvous with 16 Psyche, the heart of a demolished planet believed to be made almost entirely of iron.
Named after its interplanetary target, the $985 million mission is intended to help scientists determine whether the 140-mile-wide asteroid -- which varies between 235 million and 309 million miles away -- formed like Earth.
The Psyche spacecraft, at 10 feet-by-8 feet, is scheduled to lift off Oct. 5 aboard a SpaceX Falcon Heavy rocket from Kennedy Space Center in Florida. That will accelerate the probe to the speed it needs to escape the gravity wells of Earth and the sun.
Then, the sophisticated space probe will start one of its four Hall-effect thrusters to accelerate toward its final destination.
Called ion propulsion, its technology involves using solar electrical power to generate electromagnetic fields for charged xenon gas.
Members of the media are given an opportunity to view the NASA Psyche satellite at the Astrotech Space Operations Facility in Titusville, Fla. Photo by Joe Marino/UPI
Essentially, the electricity from the solar panels is used to convert the xenon gas to xenon ions, which are expelled to provide a very low thrust. The engines will run one at a time, for two years.
Psyche's mission was originally scheduled to launch in October 2022, but was delayed by flight software issues. That software recently passed muster and has been installed onto Psyche's systems.
The principal Investigator for the Psyche program, Lindy Elkins-Tanton, from the University of Arizona, provides an update on the NASA Psyche mission at the Astrotech Space Operations Facility in Titusville, Fla. Photo by Joe Marino/UPI
JPL manages mission
Led by Arizona State University. NASA's Jet Propulsion Laboratory in Pasadena, Calif., is responsible for mission management, operations and navigation.
NASA's Jet Propulsion Laboratory plans to send the Psyche spacecraft, to a distant metallic asteroid. Image courtesy of NASA/SSL Maxar Technologies
The spacecraft's solar-electric propulsion chassis was built by Maxar, with a payload that includes an imager, magnetometer and a gamma-ray spectrometer.
As part of its mission, Psyche will gather topographical and chemical composition data, looking for evidence of a magnetic field. Planetologists believe Psyche may still have one.
NASA's Jet Propulsion Laboratory plans to send the Psyche spacecraft to a distant metallic asteroid, 16 Psyche, shown in an illustration. Image courtesy of NASA
The most important mission goal is to establish how planets like Earth could be the result of overwhelming numbers of primordial matter collisions and debris accumulation over eons.
NASA officials were so excited by Psyche's prospects that they showed off the spacecraft last week at the Astrotech Space Operations Facility in Titusville, Fla., not far from the space center.
Scientists explained to lay observers the importance of the mission.
"All of the planets were formed in the flash of a second and it was a very chaotic period," said JPL's Henry Stone, manager of the systems engineering section. "We cannot drill down and study the core of the Earth."
Finding a body such as 16 Psyche, still in those primeval conditions would validate scientific hypotheses about the birth of the solar system, Stone said.
The asteroid was discovered on March 17, 1852, by Italian astronomer Annibale de Gasparis, a professor of astronomy at Naples University. It was named after the Greek god Psyche.
For decades, dynamic models and hypotheses predicted that in the solar system's creation, one or two planetoid cores crumbled and separated from their rocky mantels, as Psyche likely did.
Validation of model
"If we determine that that was the case, then we can conclude that, yes, that theoretical model of that early start of the solar system is now validated," Stone said. "The presence of a magnetic core and a magnetic field is what makes life possible on Earth."
But there is more than cosmological learning involved in this research, said Lindy Elkins-Tanton, Psyche principal investigator from the School of Earth and Space Exploration at Arizona State University at Tempe.
"If you can get a measurement of Psyche, then you got the original material in its original state, and then many, many of those Psyches make added up to make our Earth," Elkins-Tanton said.
"We know something about the composition of our Earth's core from remote sensing, and I think it should be a little bit different from the composition of Psyche," she said.
"Getting from one to the other is going to tell us about the process that led from no planet to planet."
It is a fundamental question about all solar systems, Elkins-Tanton said. "How do you create a habitable planet and what happens for one to become inhabitable?"
Once in Mars' vicinity, Psyche will get a so-called gravity assist that will hurl it toward the asteroid belt -- halfway between the orbits of Mars and Jupiter -- to the encounter 16Psyche. By then, it will be August 2029.
The spacecraft will go into orbit around 16 Psyche, along a descending path, 435 miles above the surface. In this initial phase, it will spend two months mapping the asteroid's surface and looking for evidence of a magnetic field.
Determining the size
At this stage, the mission will be essential for scientists to determine the size of the asteroid -- some sort of asymmetric potato, as Elkins-Tanton described it.
Gradually, Psyche will lower its orbit to 180 miles from the surface, performing topography observations, looking for evidence of a magnetic field that may have survived Psyche's demise.
The spacecraft will descend to 110 miles from the surface to perform gravitational studies. Finally, the probe will lower to its final orbit, 53 miles from the surface, to establish its chemical composition via gamma-ray and neutron spectrometers, collect images and gravity readings, and search for magnetic fields, of course.
The whole mission circling 16 Psyche is expected to last 21 months.
One ride-along experiment will test advanced laser-based communications techniques. Called Deep Space Optical Communications, the equipment will carry massive amounts of information.
This innovative technology will be vital during human exploration missions to Mars, said Abhijit Biswas, the DSOC Program system engineer at JPL.
"We need to keep updating our technology so we can enable future science missions with high-resolution data," Biswas said. "To do that, we need faster communications; we need lasers.
"You may recall the days when we used dial-up modems to go online. From that, look at us today. We have high-speed connections, we can stream videos and multiple feeds," he said.
"For outer space, we want to have virtual presence, and to do that we need faster, laser beam communications that will help us achieve that."
Passant Rabie
Mon, August 14, 2023
A development motor based on the second-stage solid rocket motor design for NASA’s Mars Ascent Vehicle (MAV) undergoes testing on March 29 at Northrop Grumman’s facility in Elkton, Maryland.
NASA’s Perseverance rover has been diligently collecting rocky samples from Mars to stow them away on the planet’s dusty surface while engineers work to develop a rocket that can launch off of another world as a crucial step in the process of retrieving the samples.
The team behind the Mars Ascent Vehicle (MAV) recently tested its first and second stage solid rocket motors in a vacuum chamber that simulated the cold temperatures on the Red Planet, according to NASA.
“This test demonstrates our nation has the capacity to develop a launch vehicle that can successfully be lightweight enough to get to Mars and robust enough to put a set of samples into orbit to bring back to Earth,” Benjamin Davis, MAV propulsion manager at NASA’s Marshall Space Flight Center, said in a statement. “The hardware is telling us that our technology is ready to proceed with development.”
Mars Sample Return is one of the most complex missions to be carried out by NASA. It involves a fleet of spacecraft, including an orbiter, lander, two helicopters, and the first rocket to launch from the surface of another planet.
MAV is a two-stage rocket with two solid rocket motors – SRM1 and SRM2. SRM1 will propel MAV away from the surface of Mars, while SRM2 will spin the rocket’s second stage to place a container with the samples in orbit around Mars so that it can be picked up by the Earth Return Orbiter.
In order to test MAV, the team prepared development motors that will help them adjust their designs before they start building the real thing. The SRM2 development motor was tested on March 29 at the Northrop Grumman facility while SRM1 was tested on April 7 at Edwards Air Force Base in California.
NASA Mars Ascent Vehicle Continues Progress Toward Mars Sample Return
SRM1 was placed in a vacuum chamber with temperatures of -4 degrees Fahrenheit (-20 degrees Celsius) to simulate conditions on Mars. For the rocket motor to survive the extreme cold, the team had to outfit it with a trapped ball nozzle with a supersonic split line as opposed to a regular gimballing solid rocket motor nozzle, which isn’t designed for the Martian climate. Nozzles are specially-shaped tubes through which hot gases flow, and they are used as part of rocket engines to produce thrust by accelerating hot exhaust.
During the test, the supersonic splitline nozzle achieved the sixth of nine technology readiness levels based on a scale developed by NASA. The new nozzle design will still undergo more testing to, “make sure it can handle the intense shaking and vibration of launch, the near vacuum of space, and the extreme heat and cold expected during MAV’s trip,” according to NASA.
The Mars samples are expected to arrive to Earth in the early 2030s, although the mission is under scrutiny after going over budget and facing possible delays. A Senate subcommittee recently threatened to cancel the mission altogether if NASA does not submit a year-by-year funding profile for Mars Sample Return within the $5.3 billion lifecycle cost outlined in the 2022 planetary science Decadal Survey.
Gizmodo
Isaac Schultz
Mon, August 14, 2023
An artist's impression of a brown dwarf (foreground) orbiting a white dwarf
An artist’s impression of a brown dwarf (foreground) orbiting a white dwarf (background, at left).
Astronomers recently spotted one of the most massive brown dwarfs known, an object between 75 and 90 times the mass of Jupiter with a beyond-scalding dayside temperature of 8,000 K (13,940° Fahrenheit.)
For comparison, the Sun’s surface is a mere 5,772 K (9,930° Fahrenheit). Astronomers observed the piping hot, supersized brown dwarf in 2019 and 2020 using the European Southern Observatory’s Very Large Telescope. Their findings were published today in Nature Astronomy.
Brown dwarfs sit at the awkward in-between that separates planets from stars. The objects are larger than gas giants like Jupiter, but teenier than small stars. Because brown dwarfs fall short of the masses necessary for stars to burn hydrogen for their nuclear fusion, the objects are sometimes called failed stars.
The recent research team took a more respectful approach, calling the object (WD 0032-317B) an “irradiated-Jupiter analogue.” The dwarf orbits a white dwarf star that sits 1,406 light-years from Earth. The astronomical team posits that the brown dwarf was in a gas envelope with its partner white dwarf until about one million years ago.
Its high temperature is something to appreciate because brown dwarfs are generally the coolest, dimmest objects on the Hertzsprung-Russell diagram that maps stars’ luminosities and effective temperatures.
The dwarf is tidally locked, meaning that its scalding dayside always faces the white dwarf, which has a surface temperature of about 37,000 K (66,140° Fahrenheit). The brown dwarf’s nightside temperature is much cooler than its star-facing side, hovering around 2,000 K (1,727° Fahrenheit.)
Comparing brown dwarfs to hot Jupiters—gas giant exoplanets that orbit their host stars closely, making them piping hot—is not new. It was proven more apt than previously realized in 2021, when astronomers found evidence of stripes and polar storms like those seen on Jupiter on brown dwarfs. But the dwarfs can also be cooler than the boiling point of water; the coldest-known brown dwarf has a frigid temperature of -10° Fahrenheit, indicating to some that it’s not a brown dwarf at all, but a rogue exoplanet.
Spotting more brown dwarfs may clarify the diversity and nature of these hot, massive objects. A new paper hosted on the preprint server arXiv describes a brown dwarf with an astoundingly quick orbit of just two hours. The dwarf was spotted by the Zwicky Transient Facility and has a mass 80 times that of Jupiter, with an effective temperature of about 1,691 K (2,584° Fahrenheit)—quite cool compared to WD 0032-317B.
Last week, a different team of astronomers published a captivating GIF of an exoplanet’s orbit. The exoplanet could be imaged because it was “at the boundary of a planet and a brown dwarf,” according to study author and Northwestern astronomer Jason Wang.
Perhaps astronomers will apply the same technique to brown dwarfs in the future, to better understand the systems the dwarfs occupy. Or, astronomers could train the Webb Space Telescope’s perceptive gaze on these irradiated-Jupiter analogues, as they’ve done before with fainter, more distant, colder dwarfs than WD 0032-317B.
More: A Trio of Extreme Brown Dwarfs Have Been Found Spinning at Their Physical Limits
Gizmodo
Angely Mercado
Mon, August 14, 2023
The shield attached to an asteroid, hanging out in our solar system.
The solution for protecting the planet from some of the sun’s rays could be a space “umbrella.” A study published the scientific journal PNAS in June outlines a University of Hawai’i researcher’s plan for hitching an umbrella or shield onto an asteroid to block some of the sun’s rays.
István Szapudi, an astronomer at the University of Hawai’i’s Institute for Astronomy, explained in the study that a shield attached to an asteroid could be developed in the future to mitigate climate change. According to the study, this could shield the planet from 1.7% of sun rays, which could slow down planetary warming.
“In Hawaiʻi, many use an umbrella to block the sunlight as they walk about during the day. I was thinking, could we do the same for Earth and thereby mitigate the impending catastrophe of climate change?” Szapudi said in a press release.
During a call with Earther, Szapudi described the asteroid umbrella like kite surfing. Instead of wind, the force that moves the sail will be the radiation from the sun that hits the shield and transfers enough momentum to move it. Though it catches the imaginatin, Szapudi’s idea isn’t possible just yet. Our current rockets cannot exert enough force to carry a large shield out into our solar system. If a method for doing this becomes possible in a few decades, then this theory could maybe, possibly, theoretically, become a realistic climate solution.
Szapudi told Earther that the paper released at the end of July could be the start of future innovation. He thinks following research could include working with asteroid experts to identify asteroids that could be manipulated to move around the Earth and block sunlight.
According to Szapudi, another factor in making his idea a reality is creating simulations of the sun shield. Future research would have to be conducted to calculate how the shield could be manufactured and assembled, how it would get into outer space, and if parts of the shielf would have to be assembled in space.
“I want to see whether there is a simple cost effective way [to do this],” he told Earther. “It’s just the very first step in a big journey,” he said.
Many other climate change mitigation geoengineering projects have been proposed, and some of these suggestions have also involved outer space. Last year, a team of researchers at the Massachusetts Institute of Technology announced an idea that included sending a huge raft of “bubbles” into outer space. The raft would be positioned between the Earth and the Sun. Theoretically, it would be big enough to deflect sunlight away from the planet to slow down some of our global warming.
Other proposed space ideas are a little scarier. Just this year, a group of researchers at Harvard and the University of Utah proposed a solution to shoot millions of tons of moon dust into Earth’s orbit. The dust would be enough to block out the Sun’s rays. But like the solution suggested in the study from the University of Hawai’i, these other geoengineering solutions are still theoretical. Technology would need to advance in order for these solutions to become possible one day.
Szapudi emphasized that geoengineering ideas, like the sun shield attached to an asteroid, are one part of mitigating the climate crisis. “We probably have to do a number of things to mitigate climate change, and this might be one of them,” he said. “Every solution needs to be explored.”
Gizmodo
The space industry is starting a green revolution
Sun, August 13, 2023
Image Credits: sbayram (opens in a new window) / Getty Images
Rocket launches are nothing short of spectacular. Whether we grew up in the Apollo era, the space shuttle era or the private space era, most of us can easily bring to mind a rocket launch with the roar of its engines, jets of fire and trails of smoke. That image is burned into the consciousness of nearly everyone on planet Earth with access to TV or internet.
But, until recently, few people considered that those spectacular launches might be leaving an awful lot of pollution in its wake. As it turns out, the space travel industry, with its several dozen launches per year, is responsible for the same amount of carbon emissions as the global aviation industry. With the commercial space industry maturing at a rapid pace, we are seeing a steady increase in the number of rocket launches every year. So, the scale of the problem is only going to grow.
The space travel industry is responsible for the same amount of carbon emissions as the global aviation industry.
In May 2022, two scientists from the University of Nicosia in Cyprus, Ioannis Kokkinakis and Dimitris Drikakis, sought to quantify the potential impact in a study that appeared in the Physics of Fluids journal. They sought to measure the potential health and climate risks by blending rocket launch data with computer simulations.
The conclusion they reached was that “pollution from rockets should not be underestimated as frequent future rocket launches could have a significant cumulative effect on climate,” and may also become “hazardous to human health.”
In the simulations, the scientists used data based on the standard rocket fuel RP-1. And therein lies one of the biggest problems that the space launch industry needs to tackle. RP-1 (alternatively, Rocket Propellant-1 or Refined Petroleum-1) is a highly refined form of kerosene that has been the standard rocket fuel used for decades. Unfortunately, RP-1 is not and never has been a clean-burning fuel. A launch using RP-1 or similar kerosene-based fuel creates many tons of CO2, as well as particulates in the atmosphere called black carbon, commonly known as soot.
However, it is not all doom and gloom. It is early days, admittedly, but it is safe to say there is a green revolution starting in the space launch industry. Positive signs are starting to appear across the global space industry and it appears to be gathering steam.
It is starting with a rethink about the fuels that are being utilized. Three emerging rocket launch companies, two in Europe and one in the U.S., have decided to build their rockets around a very different, yet very familiar fuel — propane. Strange as it may seem, what most people think of as camping gas might be a saving grace for the global space launch industry.
Propane has qualities that make it a very sustainable fuel. First, it is very clean-burning, meaning that black carbon is not left in the atmosphere. Second, its carbon footprint is minimal compared to RP-1. A study from the University of Exeter concluded that a "microlauncher" rocket using the renewable form of propane — bio-propane — could reduce CO2 emissions by up to 96% compared to other similarly sized rockets.
One spaceport currently being built in Scotland, Sutherland Spaceport, is also taking a stand on environmental sustainability. The developers of that spaceport aim to make it the first carbon-neutral spaceport globally — both in its construction and its operation. One illustration of what that means practically is how the developers plan to reuse the peat lifted from the construction to repair the peat "scars" in the landscape nearby, created by decades of harvesting peat for fuel.
Another hopeful sign from the space industry comes from the European Space Agency (ESA). They recently commissioned a study called “Ultra-Green Launch & Space Transportation Systems.” Although this is a long-term play, as it is looking for solutions to be exploited in the period 2030–2050, the fact that a major space agency is studying the issue is a positive sign of the direction that the global space industry in taking.
There is positive momentum, too, from the European Space Agency, through their leadership in tackling the issue of space debris or space junk. Anyone who has seen the movie Wall-E can picture what that might look like from space and feel a little collective shame at how humanity has reached this situation. It is thought that there are now millions of fragments of space junk in Earth’s orbit. However, one of the most comforting aspects of ESA’s leadership in this sphere is how they are actively putting resources into projects that will seek to actively remove debris, leaving our planet’s orbit cleaner and more accessible.
Five to ten years ago, you would have struggled to find anyone, anywhere connecting the words "sustainability" and "space." That is changing, and rightly so. But this is not the time to sit back and think that everything will be fine. If the space industry is to flourish in the 21st-century, sustainability will need to become a core part of its ethos.
What may begin with polite applause from the periphery for sustainability initiatives will no doubt lead to financial disincentives and eventually legislation. Even if most people are excited and inspired by rocket launches, the space industry is unlikely to get a free pass for much longer.
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