OrbitalHub

Mea AI adiutor dicit:

The Neutron Star Interior Composition Explorer (NICER) is a NASA mission launched in June 2017 and mounted on the International Space Station (ISS). Its primary objective is to study neutron stars—ultra-dense remnants of massive stars that have undergone supernova explosions. By observing X-ray emissions from these celestial objects, NICER aims to provide insights into their internal structures and the fundamental physics governing matter under extreme conditions.

NICER’s core component is the X-ray Timing Instrument (XTI), designed for high-precision timing and spectroscopy of soft X-rays in the 0.2–12 keV energy range. The XTI comprises 56 co-aligned X-ray concentrator optics, each paired with a silicon drift detector. These concentrators utilize grazing-incidence optics with 24 nested mirrors to focus incoming X-rays onto their respective detectors, enhancing sensitivity and resolution.

NICER is mounted on the ISS’s ExPRESS Logistics Carrier-2. It features a two-axis pointing system that allows the instrument to track celestial targets across the sky. An integrated star tracker ensures precise alignment, enabling NICER to observe multiple targets during each 92-minute orbit of the ISS.

To achieve its scientific goals, NICER incorporates a GPS-based timing system capable of tagging photon arrival times with sub-microsecond accuracy. This high temporal resolution is crucial for studying the rapid rotational periods of pulsars and other time-sensitive phenomena.

NICER has significantly advanced our understanding of neutron star interiors by providing precise measurements of their masses and radii. These observations have helped constrain the equation of state for ultra-dense matter, shedding light on the behavior of matter at densities exceeding those found in atomic nuclei.

An extension of NICER’s mission, known as SEXTANT (Station Explorer for X-ray Timing and Navigation Technology), successfully demonstrated the use of X-ray pulsars for autonomous spacecraft navigation. By measuring the timing of X-ray pulses from known pulsars, SEXTANT was able to determine the ISS’s position in space, paving the way for future deep-space navigation systems.

In 2018, NICER discovered an X-ray pulsar in the fastest known stellar orbit, with a companion star completing an orbit every 38 minutes. This finding provides valuable data on the dynamics of compact binary systems and the extreme gravitational environments in which they exist.

NICER observed the brightest X-ray burst ever recorded from the neutron star SAX J1808.4−3658. This event offered insights into thermonuclear processes on neutron star surfaces and the mechanisms driving such energetic emissions.

Although primarily focused on neutron stars, NICER has also contributed to black hole research. It mapped “light echoes” from the stellar-mass black hole MAXI J1820+070, revealing changes in the size and shape of the surrounding accretion disk and corona. These observations enhance our understanding of black hole accretion processes and their immediate environments.

In May 2023, NICER’s thermal shields developed a leak, allowing stray light to interfere with its X-ray detectors. To address this issue, NASA designed specialized patches delivered to the ISS via the Cygnus NG-21 resupply mission in August 2024. Astronauts successfully applied these patches during a spacewalk on January 16, 2025, restoring NICER’s full observational capabilities.

As of early 2025, NICER has contributed to over 300 scientific publications, underscoring its significant role in advancing astrophysical research. Its high-precision measurements continue to provide valuable data for the scientific community, enhancing our understanding of neutron stars and other cosmic phenomena.

Video credit: NASA Goddard

nbsp;


nbsp;

NASA dicit:

SpaceX’s Falcon 9 rocket, with the company’s uncrewed Dragon spacecraft on top, lifted off from NASA’s Kennedy Space Center in Florida.

Loaded with scientific experiments and supplies, the unpiloted SpaceX CRS-27 cargo ship automatically docked to the International Space Station’s forward port of the Harmony module March 16. The SpaceX resupply craft will remain on orbit for a month-long visit.

Credit: NASA/SpaceX

Wikipedia dicit:

The Cygnus spacecraft is an expendable American cargo spacecraft developed by Orbital Sciences Corporation and now manufactured and launched by Northrop Grumman Space Systems as part of NASA’s Commercial Resupply Services (CRS) program. It is launched by Northrop Grumman’s Antares rocket or ULA’s Atlas V and is designed to transport supplies to the International Space Station (ISS) following the retirement of the American Space Shuttle.

Since August 2000, ISS resupply missions have been regularly flown by the Russian Progress spacecraft, as well as by the European Automated Transfer Vehicle, and the Japanese H-II Transfer Vehicle. With the Cygnus spacecraft and the SpaceX Dragon, NASA seeks to increase its partnerships with domestic commercial aviation and aeronautics industry.

The Cygnus spacecraft consists of two basic components: the Pressurized Cargo Module (PCM) and the Service Module (SM). The PCM is manufactured by Thales Alenia Space in Turin, (Italy). The initial PCMs have an empty mass of 1,500 kg and a volume of 18 m3·. The service module is built by Orbital ATK and is based on their GEOStar and LEOStar spacecraft buses as well as components from the development of the Dawn spacecraft. It has a gross mass of 1,800 kg with propulsion provided by thrusters using the hypergolic propellants hydrazine and nitrogen tetroxide (the propellant mass is 800 kg). The service module is capable of producing up to 4 kW of electrical power via two gallium arsenide solar arrays. On 12 November 2009, Dutch Space announced it will provide the solar arrays for the initial Cygnus spacecraft.

Video credit: NASA

NASA dicit:

SpaceX CRS-23, also known as SpX-23, is a Commercial Resupply Service mission to the International Space Station. The mission was contracted by NASA and was flown by SpaceX using the Cargo Dragon C208. This was the third flight for SpaceX under NASA’s CRS Phase 2 contract awarded in January 2016. A NASA Flight Planning Integration Panel (FPIP) from 2019 indicates that SpaceX cargo missions will begin to extend their duration to 60 days and beyond starting with CRS-23.

SpaceX plans to reuse the Cargo Dragons up to five times. The Cargo Dragon launches without SuperDraco abort engines, without seats, cockpit controls and the life support system required to sustain astronauts in space. This newer design provides several benefits, including a faster process to recover, refurbish and re-fly versus the earlier Dragon CRS design used for ISS cargo missions.

The GITAI S1 Robotic Arm Tech Demo will test GITAI Japan Inc.’s microgravity robot by placing the arm inside the newly added Nanoracks Bishop Airlock, which was carried to the station by Dragon C208.2 during the SpaceX CRS-21 mission last year. Once inside the airlock, the arm will perform numerous tests to demonstrate its versatility and dexterity.

Designed by GITAI Japan Inc., the robot will work as a general-purpose helper under the pressurized environment inside the Bishop Airlock. It will operate tools and switches and run scientific experiments. The next step will be to test it outside the ISS in the harsh space environment. The robot will be able to perform tasks both autonomously and via teleoperations. Its arm has eight degrees of freedom and a 1-meter reach. GITAI S1 is a semi-autonomous/semi-teleoperated robotic arm designed to conduct specified tasks internally and externally on space stations, on-orbit servicing, and lunar base development. By combining autonomous control via AI and teleoperations via the specially designed GITAI manipulation system H1, GITAI S1 on its own, possesses the capability to conduct generous-purpose tasks (manipulation of switches, tools, soft objects; conducting science experiments and assembly; high-load operations; etc.) that were extremely difficult for industrial robots such as task specific robotic arms to do.

Video credit: NASA/SpaceX

NASA dicit:

Scientists have reached a new frontier in our understanding of pulsars, the dense, whirling remains of exploded stars, thanks to observations from NASA’s Neutron star Interior Composition Explorer (NICER). Data from this X-ray telescope aboard the International Space Station has produced the first precise and dependable measurements of both a pulsar’s size and its mass.

The pulsar in question, J0030+0451 (J0030 for short), is a solitary pulsar that lies 1,100 light-years away in the constellation Pisces. While measuring the pulsar’s heft and proportions, NICER revealed that the shapes and locations of million-degree hot spots on the pulsar’s surface are much stranger than generally thought.

Using NICER observations, two groups of scientists mapped J0030’s hot spots using independent methods and converged on nearly identical results for its mass and size. One team, led by researchers at the University of Amsterdam, determined the pulsar is around 1.3 times the Sun’s mass, 15.8 miles (25.4 kilometers) across and has two hot spots — one small and circular, the other long and crescent-shaped. A second team found J0030 is about 1.4 times the Sun’s mass, about 16.2 miles (26 kilometers) wide and has two or three oval-shaped hot spots. All spots in all models are in the pulsar’s southern hemisphere — unlike textbook images where the spots lie on opposite sides other at each magnetic poles.

Video credit: NASA’s Goddard Space Flight Center/Scott Wiessinger (USRA): Producer/Jeanette Kazmierczak (University of Maryland College Park): Science Writer/Francis Reddy (University of Maryland College Park): Science Writer/Michael Lentz (USRA): Animator/Barb Mattson (University of Maryland College Park): Narrator/Zaven Arzoumanian (NASA/GSFC): Scientist

NASA dicit:

Cameras outside the International Space Station captured dramatic views of Hurricane Zeta at 12:50 p.m. Eastern time Wednesday October 28, 2020 as the storm churned 200 miles south-southwest of New Orleans packing winds of 90 miles an hour.

Zeta is expected to make landfall near New Orleans later in the day Wednesday October 28 as a Category 2 hurricane before accelerating to the northeast.

Video credit: NASA