OrbitalHub

Wikipedia dicit:

Landsat 8 is an American Earth observation satellite launched on 11 February 2013. It is the eighth satellite in the Landsat program; the seventh to reach orbit successfully. Originally called the Landsat Data Continuity Mission (LDCM), it is a collaboration between NASA and the United States Geological Survey (USGS). NASA Goddard Space Flight Center in Greenbelt, Maryland, provided development, mission systems engineering, and acquisition of the launch vehicle while the USGS provided for development of the ground systems and will conduct on-going mission operations. It comprises the camera of the Operational Land Imager (OLI) and the Thermal Infrared Sensor (TIRS), which can be used to study Earth surface temperature and is used to study global warming.

The satellite was built by Orbital Sciences Corporation, who served as prime contractor for the mission. The spacecraft’s instruments were constructed by Ball Aerospace & Technologies and NASA’s Goddard Space Flight Center (GSFC), and its launch was contracted to United Launch Alliance (ULA). During the first 108 days in orbit, LDCM underwent checkout and verification by NASA and on 30 May 2013 operations were transferred from NASA to the USGS when LDCM was officially renamed to Landsat 8.

Credit: NASA Goddard

Wikipedia dicit:

Curiosity is a car-sized Mars rover designed to explore the Gale crater on Mars as part of NASA’s Mars Science Laboratory (MSL) mission. Curiosity was launched from Cape Canaveral (CCAFS) on November 26, 2011, at 15:02:00 UTC and landed on Aeolis Palus inside Gale crater on Mars on August 6, 2012, 05:17:57 UTC. The Bradbury Landing site was less than 2.4 km (1.5 mi) from the center of the rover’s touchdown target after a 560 million km (350 million mi) journey.

Mission goals include an investigation of the Martian climate and geology, assessment of whether the selected field site inside Gale has ever offered environmental conditions favourable for microbial life (including investigation of the role of water), and planetary habitability studies in preparation for human exploration.

In December 2012, Curiosity’s two-year mission was extended indefinitely, and on August 5, 2017, NASA celebrated the fifth anniversary of the Curiosity rover landing. On August 6, 2022, a detailed overview of accomplishments by the Curiosity rover for the last ten years was reported. The rover is still operational, and as of 11 February 2023, Curiosity has been active on Mars for 3739 sols (3841 total days; 10 years, 189 days) since its landing.

Credit: NASA’s Marshall Space Flight Center

Wikipedia dicit:

A rotating detonation engine (RDE) is an engine using a form of pressure gain combustion, where one or more detonations continuously travel around an annular channel. Computational simulations and experimental results have shown that the RDE has potential in transport and other applications.

In detonative combustion, the results expand at supersonic speed. It is theoretically more efficient than conventional deflagrative combustion by as much as 25%. Such an efficiency gain would provide major fuel savings. Disadvantages include instability and noise.

The basic concept of an RDE is a detonation wave that travels around a circular channel (annulus). Fuel and oxidizer are injected into the channel, normally through small holes or slits. A detonation is initiated in the fuel/oxidizer mixture by some form of igniter. After the engine is started, the detonations are self-sustaining. One detonation ignites the fuel/oxidizer mixture, which releases the energy necessary to sustain the detonation. The combustion products expand out of the channel and are pushed out of the channel by the incoming fuel and oxidizer.

Although the RDE’s design is similar to the pulse detonation engine (PDE), the RDE is superior because the waves cycle around the chamber, while the PDE requires the chambers to be purged after each pulse.

Credit: NASA’s Marshall Space Flight Center

Wikipedia dicit:

A launch escape system (LES) or launch abort system (LAS) is a crew-safety system connected to a space capsule that can be used to quickly separate the capsule from its launch vehicle in case of an emergency requiring the abort of the launch, such as an impending explosion. The LES is typically controlled by a combination of automatic rocket failure detection, and a manual activation for the crew commander’s use. The LES may be used while the launch vehicle is still on the launch pad, or during its ascent. Such systems are usually of two types: solid-fuelled rocket or ejection seats.

A solid-fuelled rocket, mounted above the capsule on a tower, which delivers a relatively large thrust for a brief period of time to send the capsule a safe distance away from the launch vehicle, at which point the capsule’s parachute recovery system can be used for a safe landing on ground or water. The tower and rocket are jettisoned from the space vehicle in a normal flight at the point where it is either no longer needed, or cannot be effectively used to abort the flight. These have been used on the Mercury, Apollo, Soyuz, and Shenzhou capsules.

The crew are seated in seats that eject themselves (ejection seats) as used in military aircraft; each crew member returns to Earth with an individual parachute. Such systems are effective only in a limited range of altitudes and speeds. These have been used on the Vostok and Gemini capsules.

Credit: NASA’s Ames Research 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 Goddard dicit:

This video chronicles solar activity from Aug. 12 to Dec. 22, 2022, as captured by NASA’s Solar Dynamics Observatory (SDO). From its orbit in space around Earth, SDO has steadily imaged the Sun in 4K x 4K resolution for nearly 13 years. This information has enabled countless new discoveries about the workings of our closest star and how it influences the solar system.

With a triad of instruments, SDO captures an image of the Sun every 0.75 seconds. The Atmospheric Imaging Assembly (AIA) instrument alone captures images every 12 seconds at 10 different wavelengths of light. This 133-day time lapse showcases photos taken at a wavelength of 17.1 nanometers, which is an extreme-ultraviolet wavelength that shows the Sun’s outermost atmospheric layer: the corona. Compiling images taken 108 seconds apart, the movie condenses 133 days, or about four months, of solar observations into 59 minutes. The video shows bright active regions passing across the face of the Sun as it rotates. The Sun rotates approximately once every 27 days. The loops extending above the bright regions are magnetic fields that have trapped hot, glowing plasma. These bright regions are also the source of solar flares, which appear as bright flashes as magnetic fields snap together in a process called magnetic reconnection.

While SDO has kept an unblinking eye pointed toward the Sun, there have been a few moments it missed. Some of the dark frames in the video are caused by Earth or the Moon eclipsing SDO as they pass between the spacecraft and the Sun. Other blackouts are caused by instrumentation being down or data errors. SDO transmits 1.4 terabytes of data to the ground every day. The images where the Sun is off-center were observed when SDO was calibrating its instruments.

SDO and other NASA missions will continue to watch our Sun in the years to come, providing further insights about our place in space and information to keep our astronauts and assets safe.

Music Credit: The music is a continuous mix from Lars Leonhard’s “Geometric Shapes” album, courtesy of the artist.

Credit: NASA’s Goddard Space Flight Center/Scott Wiessinger (PAO): Lead Producer/Tom Bridgman (SVS): Lead Visualizer/Scott Wiessinger (PAO): Editor