OrbitalHub

Wikipedia dicit:

The Aerojet Rocketdyne RS-25, also known as the Space Shuttle Main Engine (SSME), is a liquid-fuel cryogenic rocket engine that was used on NASA’s Space Shuttle. NASA is planning to continue using the RS-25 on the Space Shuttle’s successor, the Space Launch System (SLS).

Designed and manufactured in the United States by Rocketdyne (later known as Pratt & Whitney Rocketdyne and Aerojet Rocketdyne), the RS-25 burns cryogenic liquid hydrogen and liquid oxygen propellants, with each engine producing 1,859 kN (418,000 lbf) of thrust at liftoff. Although the RS-25 can trace its heritage back to the 1960s, the concerted development of the engine began in the 1970s, with the first flight, STS-1, occurring on April 12, 1981. The RS-25 has undergone several upgrades over its operational history to improve the engine’s reliability, safety, and maintenance load.

The engine produces a specific impulse (Isp) of 452 seconds (4.43 km/s) in a vacuum, or 366 seconds (3.59 km/s) at sea level, has a mass of approximately 3.5 tonnes (7,700 pounds), and is capable of throttling between 67% and 109% of its rated power level in one-percent increments. Components of the RS-25 operate at temperatures ranging from −253 to 3,300 °C (−400 to 6,000 °F).

The Space Shuttle used a cluster of three RS-25 engines mounted in the stern structure of the orbiter, with fuel being drawn from the external tank. The engines were used for propulsion during the entirety of the spacecraft’s ascent, with additional thrust being provided by two solid rocket boosters and the orbiter’s two AJ10 orbital maneuvering system engines. Following each flight, the RS-25 engines were removed from the orbiter, inspected, and refurbished before being reused on another mission. On Space Launch System flights, the engines will be expendable. For the first four flights, engines left over from the Space Shuttle program will be refurbished and used before NASA switches to the simplified RS-25E variant.

Video credit: NASA’s Kennedy Space Center

They will always be remembered…

Apollo 1 (January 27, 1967)

Virgil “Gus” Grissom – Commander, Edward White – Command Pilot, Roger Chaffee – Pilot

STS-51 L (January 28, 1986)

Francis R. Scobee – Commander, Michael J. Smith – Pilot, Judith A. Resnik – Mission Specialist 1, Ellison Onizuka – Mission Specialist 2, Ronald E. McNair – Mission Specialist 3, Gregory B. Jarvis – Payload Specialist 1, Sharon Christa McAuliffe – Payload Specialist 2

STS-107 (February 1, 2003)

Rick D. Husband – Commander, William C. McCool – Pilot, Michael P. Anderson – Payload Commander, David M. Brown – Mission Specialist 1, Kalpana Chawla – Mission Specialist 2, Laurel Clark – Mission Specialist 3, Ilan Ramon – Payload Specialist 1

Video credit: NASA

NASA dicit:

Seasons change even on Mars and NASA’s fleet of explorers are helping scientists learn more about the effects on the Red Planet. NASA’s Perseverance and Curiosity rovers provide daily weather reports by measuring conditions such as humidity, temperature, and wind speed on the surface. Orbiters including Odyssey, Mars Atmosphere and Volatile EvolutioN (MAVEN), and the Mars Reconnaissance Orbiter (MRO) survey the scope and scale of storms from above. Changing weather conditions can be challenging for the spacecraft. The Ingenuity Mars Helicopter recently increased its rotor speed from 2,537 rpm to 2,700 rpm to fly in a thinner summer atmosphere. Meanwhile, NASA’s InSight lander, which is studying Mars’ interior, recently measured one of the biggest, longest-lasting marsquakes the mission has ever detected.

Video credit: NASA/JPL-Caltech/University of Arizona/ASU/MSSS

NASA dicit:

Guided tour of Mars’ Jezero Crater from NASA’s Perseverance rover provides a glimpse of the Martian landscape from the rover’s highest vantage point yet in the “Séítah” region.

Perseverance Project Scientist Ken Farley points out highlights in this Martian panorama from the rover’s Mastcam-Z instrument, including mountains that make up the crater rim, remnants of an ancient river delta that could preserve signs of ancient life, volcanic rocks, and boulders likely carried into the crater by the river in the distant past. The enhanced-color panorama was created from images taken on November 28, 2021.

The color enhancement exaggerates small changes in color from place to place in the scene. This makes it easier for the science team to use their everyday experience to interpret the landscape. The sky on Mars would not actually look blue to a human explorer on the Red Planet, but pinkish.

Video credit: NASA Jet Propulsion Laboratory

NASA’s SpaceX 24th commercial resupply services mission liftoff.

Video credit: NASA/SpaceX

Wikipedia dicit:

The Imaging X-ray Polarimetry Explorer, commonly known as IXPE, is a space observatory with three identical telescopes designed to measure the polarization of cosmic X-rays. The mission will study exotic astronomical objects and permit mapping the magnetic fields of black holes, neutron stars, pulsars, supernova remnants, magnetars, quasars, and active galactic nuclei. The high-energy X-ray radiation from these objects’ surrounding environment can be polarized – vibrating in a particular direction. Studying the polarization of X-rays reveals the physics of these objects and can provide insights into the high-temperature environments where they are created.

The IXPE mission was announced on 3 January 2017. It is being developed by NASA’s Small Explorer program (SMEX) and is slated for launch on 9 December 2021. The estimated cost of the mission and its two-year operation is US$188 million (the launch cost is US$50.3 million). The goal of the IXPE mission is to expand understanding of high-energy astrophysical processes and sources, in support of NASA’s first science objective in astrophysics: “Discover how the universe works”. By obtaining X-ray polarimetry and polarimetric imaging of cosmic sources, IXPE addresses two specific science objectives: to determine the radiation processes and detailed properties of specific cosmic X-ray sources or categories of sources; and to explore general relativistic and quantum effects in extreme environments.

During IXPE’s two-year mission, it will study targets such as active galactic nuclei, quasars, pulsars, pulsar wind nebulae, magnetars, accreting X-ray binaries, supernova remnants, and the Galactic Center.

Video credit: NASA