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By Space Force
U.S. Air Force Lt. Gen. John DeGoes discusses transformative leadership and how it is rooted in purposeful communication, adaptability, and a commitment to the Air Force core values.
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By USH
During an interview with Chris Letho, Dr. Courtney Brown, a university professor and founder of Farsight.org, an organization known for its remote-viewing phenomenon through the process of scientific experimentation, has made a bold prediction: larger UFOs will begin appearing in increasing numbers across the U.S. in the next month. He asserts their presence will serve as undeniable proof that humanity is not alone in the universe, forcing governments to disclose the truth about alien life.
While intriguing, this claim has been met with skepticism. Could it be true that aliens are stepping forward to force disclosure? Or, might this be part of a staged event orchestrated by shadowy forces, such as the "Deep State," to stage an UFO invasion.
Recently, a witness in California filmed a massive craft with flickering lights hovering silently over a city. This object, described as far larger than the drones or UFOs previously reported, has sparked further speculation. Witnesses noted that these objects appear to be increasing in size, and many argue they are clearly not conventional drones.
The sighting raises questions: could this lend credibility to Dr. Brown’s claims of imminent extraterrestrial revelation? Or are these larger crafts part of a deceptive agenda, as explained by Dark Journalist? See our previous article: Mystery drones: A 'dry run' to a false UFO event to trigger COG emergency powers.
One way or another, we will know in the coming months!
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By NASA
X-rays are radiated by matter hotter than one million Kelvin, and high-resolution X-ray spectroscopy can tell us about the composition of the matter and how fast and in what direction it is moving. Quantum calorimeters are opening this new window on the Universe. First promised four decades ago, the quantum-calorimeter era of X-ray astronomy has finally dawned.
Photo of the XRISM/Resolve quantum-calorimeter array in its storage container prior to integration into the instrument. The 6×6 array, 5 mm on a side, consists of independent detectors – each one a thermally isolated silicon thermistor with a HgTe absorber. The spectrometer consisting of this detector and other essential technologies separates astrophysical X-ray spectra into about 2400 resolution elements, which can be thought of as X-ray colors.NASA GSFC A quantum calorimeter is a device that makes precise measurements of energy quanta by measuring the temperature change that occurs when a quantum of energy is deposited in an absorber with low heat capacity. The absorber is attached to a thermometer that is somewhat decoupled from a heat sink so that the sensor can heat up and then cool back down again. To reduce thermodynamic noise and the heat capacity of the sensor, operation at temperatures less than 0.1 K is required.
The idea for thermal measurement of small amounts of energy occurred in several places in the world independently when scientists observed pulses in the readout of low-temperature thermometers and infrared detectors. They attributed these spurious signals to passing cosmic-ray particles, and considered optimizing detectors for sensitive measurement of the energy of particles and photons.
The idea to develop such sensors for X-ray astronomy was conceived at Goddard Space Flight Center in 1982 when X-ray astronomers were considering instruments to propose for NASA’s planned Advanced X-ray Astrophysics Facility (AXAF). In a fateful conversation, infrared astronomer Harvey Moseley suggested thermal detection could offer substantial improvement over existing solid-state detectors. Using Goddard internal research and development funding, development advanced sufficiently to justify, just two years later, proposing a quantum-calorimeter X-ray Spectrometer (XRS) for inclusion on AXAF. Despite its technical immaturity at the time, the revolutionary potential of the XRS was acknowledged, and the proposal was accepted.
The AXAF design evolved over the subsequent years, however, and the XRS was eliminated from its complement of instruments. After discussions between NASA and the Japanese Institute of Space and Astronautical Science (ISAS), a new XRS was included in the instrument suite of the Japanese Astro-E X-ray observatory. Astro-E launched in 2000 but did not reach orbit due to an anomaly in the first stage of the rocket. Astro-E2, a rebuild of Astro-E, was successfully placed in orbit in 2005 and renamed Suzaku, but the XRS instrument ceased operation before observations started due to loss of the liquid helium, an essential part of the detector cooling system, caused by a faulty storage system.
A redesigned mission, Astro-H, that included a quantum-calorimeter instrument with a redundant cooling system was successfully launched in 2016 and renamed Hitomi. Hitomi’s Soft X-ray Spectrometer (SXS) obtained high resolution spectra of the Perseus cluster of galaxies and a few other sources before a problem with the attitude control system caused the mission to be lost roughly one month after launch. Even so, Hitomi was the first orbiting observatory to obtain a scientific result using X-ray quantum calorimeters. The spectacular Perseus spectrum generated by the SXS motivated yet another attempt to implement a spaceborne quantum-calorimeter spectrometer.
The X-ray Imaging and Spectroscopy Mission (XRISM) was launched in September 2023, with the spectrometer aboard renamed Resolve to represent not only its function but also the resolve of the U.S./Japan collaboration to study the Universe through the window of this new capability. XRISM has been operating well in orbit for over a year.
Development of the Sensor Technology
Development of the sensor technology employed in Resolve began four decades ago. Note that an X-ray quantum-calorimeter spectrometer requires more than the sensor technology. Other technologies, such as the coolers that provide a
The sensors used from XRS through Resolve were all based on silicon-thermistor thermometers and mercury telluride (HgTe) X-ray absorbers. They used arrays consisting of 32 to 36 pixels, each of which was an independent quantum calorimeter. Between Astro-E and Astro-E2, a new method of making the thermistor was developed that significantly reduced its low-frequency noise. Other fabrication advances made it possible to make reproducible connections between absorbers and thermistors and to fit each thermistor and its thermal isolation under its X-ray absorber, making square arrays feasible.
Through a Small Business Innovation Research (SBIR) contract executed after the Astro-E2 mission, EPIR Technologies Inc. reduced the specific heat of the HgTe absorbers. Additional improvements made to the cooler of the detector heat sink allowed operation at a lower temperature, which further reduced the specific heat. Together, these changes enabled the pixel width to be increased from 0.64 mm to 0.83 mm while still achieving a lower heat capacity, and thus improving the energy resolution. From Astro-E through Astro-H, the energy resolution for X-rays of energy around 6000 eV improved from 11 eV, to 5.5 eV, to 4 eV. No changes to the array design were made between Astro-H and XRISM.
Resolve detector scientist Caroline Kilbourne installing the flight Resolve quantum-calorimeter array into the assembly that provides its electrical, thermal, and mechanical interfaces.NASA GSFC Over the same period, other approaches to quantum-calorimeter arrays optimized for the needs of future missions were developed. The use of superconducting transition-edge sensors (TES) instead of silicon (Si) thermistors led to improved energy resolution, more pixels per array, and multiplexing (a technique that allows multiple signals to be carried on a single wire). Quantum-calorimeter arrays with thousands of pixels are now standard, such as in the NASA contribution to the future European New Advanced Telescope for High-ENergy Astrophysics (newAthena) mission. And quantum calorimeters using paramagnetic thermometers — which unlike TES and Si thermistors require no dissipation of heat in the thermometer for it to be read out — combined with high-density wiring are a promising route for realizing even larger arrays. (See Astrophysics Technology Highlight on these latest developments.)
The Resolve instrument aboard XRISM (X-ray Imaging and Spectroscopy Mission) captured data from the center of galaxy NGC 4151, where a supermassive black hole is slowly consuming material from the surrounding accretion disk. The resulting spectrum reveals the presence of iron in the peak around 6.5 keV and the dips around 7 keV, light thousands of times more energetic that what our eyes can see. Background: An image of NGC 4151 constructed from a combination of X-ray, optical, and radio light.Spectrum: JAXA/NASA/XRISM Resolve. Background: X-rays, NASA/CXC/CfA/J.Wang et al.; optical, Isaac Newton Group of Telescopes, La Palma/Jacobus Kapteyn Telescope; radio, NSF/NRAO/VLA Results from Resolve
So, what is Resolve revealing about the Universe? Through spectroscopy alone, Resolve allows us to construct images of complex environments where collections of gas and dust with various attributes exist, emitting and absorbing X-rays at energies characteristic of their various compositions, velocities, and temperatures. For example, in the middle of the galaxy known as NCG 4151 (see figure above), matter spiraling into the central massive black hole forms a circular structure that is flat near the black hole, more donut-shaped further out, and, according to the Resolve data, a bit lumpy. Matter near the black hole is heated up to X-ray-emitting temperatures and irradiates the matter in the circular structure. The Resolve spectrum has a bright narrow emission line (peak) from neutral iron atoms that must be coming from colder matter in the circular structure, because hotter material would be ionized, and would have a different emission signature. Nonetheless, the shape of the iron line needs three components to describe it, each coming from a different lump in the circular structure. The presence of absorption lines (dips) in the spectrum provides further detail about the structure of the infalling matter.
A second example is the detection of X-ray emission by Resolve from the debris of stars that have exploded, such as N132D (see figure below), that will improve our understanding of the explosion mechanism and how the elements produced in stars get distributed, and allow us to infer the type of star each was before ending in a supernova. Elements are identified by their characteristic emission lines, and shifts of those lines via the Doppler effect tell us how fast the material is moving.
XRISM’s Resolve instrument captured data from supernova remnant N132D in the Large Magellanic Cloud to create the most detailed X-ray spectrum of the object ever made. The spectrum reveals peaks associated with silicon, sulfur, argon, calcium, and iron. Inset at right is an image of N132D captured by XRISM’s Xtend instrument.JAXA/NASA/XRISM Resolve and Xtend These results are just the beginning. The rich Resolve data sets are identifying complex velocity structures, rare elements, and multiple temperature components in a diverse ensemble of cosmic objects. Welcome to the quantum calorimeter era! Stay tuned for more revelations!
Project Leads: Dr. Caroline Kilbourne, NASA Goddard Space Flight Center (GSFC), for silicon-thermistor quantum calorimeter development from Astro-E2 through XRISM and early TES development. Foundational and other essential leadership provided by Dr. Harvey Moseley, Dr. John Mather, Dr. Richard Kelley, Dr. Andrew Szymkowiak, Mr. Brent Mott, Dr. F. Scott Porter, Ms. Christine Jhabvala, Dr. James Chervenak (GSFC at the time of the work) and Dr. Dan McCammon (U. Wisconsin).
Sponsoring Organizations and Programs: The NASA Headquarters Astrophysics Division sponsored the projects, missions, and other efforts that culminated in the development of the Resolve instrument.
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By NASA
A salute is widely recognized as a display of respect, but did you know it also means ‘hello’ in American Sign Language?
It is one of the signs that Jesse Bazley, International Space Station/Commercial Low Earth Orbit Development Program integration team lead, subtly incorporates into his daily interactions with colleagues at NASA’s Johnson Space Center in Houston.
In May 2021, Jesse Bazley worked his final shift as an Environmental and Thermal Operating Systems flight controller in the Mission Control Center at NASA’s Johnson Space Center in Houston. Image courtesy of Jesse Bazley Bazley is hard of hearing, which has at times presented challenges in his daily work – particularly during his stint as an Environmental and Thermal Operating Systems flight controller for the space station. “Working on console [in the Mission Control Center], you must listen to dozens of voice loops at a time, sometimes in different languages,” he said, adding that the standard-issue headset for flight controllers was not compatible with his hearing aids. Bazley adapted by obtaining a headset that fit over his hearing aids, learning how to adjust the audio system’s volume, and limiting over-the-air discussions when possible.
Bazley has been part of the NASA team for 17 years, filling a variety of roles that support the International Space Station. One of his proudest achievements occurred early in his tenure. Bazley was an intern at Marshall Space Flight Center in Huntsville, Alabama, in 2006 when the space station’s Water Recovery System was being tested. The system converts the station’s wastewater into drinkable water for the crew. When he arrived at Johnson one year later, his first assignment was to assist with the system’s procedure and display development for its incorporation into the space station’s core operations. “Now, 16 years later, it is commonplace for the space station to ‘turn yesterday’s coffee into tomorrow’s coffee’,” he said.
Jesse Bazley supporting the Atmosphere and Consumables Engineer console during the STS-127 mission in July 2009. NASA His favorite project so far has been integrating the station’s Thermal Amine Scrubber – which removes carbon dioxide from the air – into station operations. “I worked it from the beginning of NASA’s involvement, helping the provider with software testing and the integration of a brand-new Mission Control Center communications architecture,” he said.
Today, Bazley works to integrate subject matter experts from Johnson’s Flight Operations Directorate (FOD) into the processes of the International Space Station and Commercial Low Earth Orbit Development Programs. “I help pull together FOD positions on topics and coordinate reviews of provider materials to ensure that the operations perspective is maintained as development moves forward,” he explained.
While Bazley no longer supports a console, he must continue adapting to difficult hearing environments. He uses the captioning tools available through videoconferencing software during frequent team meetings, for example. “It’s important to understand that people have visible and invisible disabilities,” he said. “Sometimes their request for a remote option is not because they want to avoid an in-person meeting. It may be that they work best using the features available in that virtual environment.”
Bazley also chairs the No Boundaries Employee Resource Group, which promotes the development, inclusion, and innovation of Johnson’s workforce with a focus on employees with disabilities and employees who are caregivers of family members with disabilities.
From these diverse roles and experiences, Bazley has learned to listen to his gut instincts. “In flight operations, you must work with short timelines when things happen in-orbit, so you have to trust your training,” he said. “Understanding when you have enough information to proceed is critical to getting things done.”
Bazley looks forward to the further commercialization of low Earth orbit so NASA can focus resources on journeying to the Moon and Mars. “Aviation started out as government-funded and now is commonplace for the public. I look forward to seeing how that evolution progresses in low Earth orbit.”
His advice to the Artemis Generation is to consider the long-term impact of their actions and decisions. “What looks great on paper may not be a great solution when you have to send 10 commands just to do one task, or when the crew has to put their hand deep into the spacecraft to actuate a manual override,” he said. “The decisions you make today will be felt by operations in the future.”
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