OrbitalHub

Wikipedia dicit:

The three major components of the Mars 2020 spacecraft are the 539 kg (1,188 lb) cruise stage for travel between Earth and Mars; the Entry, Descent, and Landing System (EDLS) that includes the 575 kg (1,268 lb) aeroshell descent vehicle + 440 kg (970 lb) heat shield; and the 1,070 kg (2,360 lb) (fueled mass) sky crane needed to deliver Perseverance and Ingenuity safely to the Martian surface. The Sky Crane carries 400 kg (880 lb) landing propellant for the final soft landing burn after being slowed down by a 21.5 m (71 ft) wide 81 kg (179 lb) parachute. The 1,025 kg (2,260 lb) rover is based on the design of Curiosity. While there are differences in scientific instruments and the engineering required to support them, the entire landing system (including the sky crane and heat shield) and rover chassis could essentially be recreated without any additional engineering or research. This reduces overall technical risk for the mission, while saving funds and time on development.

One of the upgrades is a guidance and control technique called “Terrain Relative Navigation” (TRN) to fine-tune steering in the final moments of landing. This system will allow for a landing accuracy within 40 m (130 ft) and avoid obstacles. This is a marked improvement from the Mars Science Laboratory mission that had an elliptical area of 7 by 20 km (4.3 by 12.4 mi). In October 2016, NASA reported using the Xombie rocket to test the Lander Vision System (LVS), as part of the Autonomous Descent and Ascent Powered-flight Testbed (ADAPT) experimental technologies, for the Mars 2020 mission landing, meant to increase the landing accuracy and avoid obstacle hazards.

Video credit: Aerojet Rocketdyne

Lockheed Martin dicit:

Protecting a Mars Rover against the extremes of space travel is critical to the success of any mission. At Lockheed Martin, we’ve built aeroshells to protect all 10 of NASA’s Mars-bound landers and rovers.

For NASA’s latest mission — Mars 2020, which includes the Perseverance rover and Ingenuity helicopter — we built the protective aeroshell and helicopter delivery system. Mars 2020 will attempt the most challenging entry, descent and landing (EDL) sequences ever at Mars. The rover will touch down in the treacherous Jezero Crater, a region filled with boulders, rocky cliffs and shifting sand dunes.

Video credit: Lockheed Martin

SpaceX dicit:

On Tuesday, February 2, Starship serial number 9 (SN9) completed SpaceX’s second high-altitude flight test of a Starship prototype from our site in Cameron County, Texas.

Similar to the high-altitude flight test of Starship serial number 8 (SN8), SN9 was powered through ascent by three Raptor engines, each shutting down in sequence prior to the vehicle reaching apogee – approximately 10 kilometers in altitude. SN9 successfully performed a propellant transition to the internal header tanks, which hold landing propellant, before reorienting itself for reentry and a controlled aerodynamic descent.

The Starship prototype descended under active aerodynamic control, accomplished by independent movement of two forward and two aft flaps on the vehicle. All four flaps are actuated by an onboard flight computer to control Starship’s attitude during flight and enable precise landing at the intended location. During the landing flip maneuver, one of the Raptor engines did not relight and caused SN9 to land at high speed and experience a RUD.

These test flights are all about improving our understanding and development of a fully reusable transportation system designed to carry both crew and cargo on long-duration, interplanetary flights and help humanity return to the Moon, and travel to Mars and beyond.

Video credit: SpaceX

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:

Globally, 2020 was the hottest year on record, effectively tying 2016, the previous record. Overall, Earth’s average temperature has risen more than 2 degrees Fahrenheit since the 1880s. Temperatures are increasing due to human activities, specifically emissions of greenhouse gases, like carbon dioxide and methane.

Video credit: NASA’s Goddard Space Flight Center/Scientific Visualization Studio/Kathryn Mersmann (USRA): Lead Producer/Katie Jepson (USRA): Lead Producer/Jessica Merzdorf (Telophase): Lead Writer/Sofie L. Bates (Intern): Lead Writer/Peter H. Jacobs (NASA/GSFC): Public Affairs Officer/Gavin A. Schmidt (NASA/GSFC GISS): Lead Scientist/Lesley Ott (NASA/GSFC): Scientist/Lori Perkins (NASA/GSFC): Lead Visualizer/Trent L. Schindler (USRA): Visualizer/Jefferson Beck (USRA): Producer/Kathleen Gaeta (GSFC Interns): Producer/Jacob Richmond (NASA/GSFC): Public Affairs Officer

Wikipedia dicit:

A brown dwarf is a type of substellar object that has a mass between the most massive gas giant planets and the least massive stars, approximately 13 to 80 times that of Jupiter (MJ).

Unlike main sequence stars, brown dwarfs do not acquire enough mass to trigger sustained nuclear fusion of ordinary hydrogen (1H) into helium in their cores. For this reason brown dwarfs are sometimes referred to as failed stars. They are, however, thought to fuse deuterium (2H), and to fuse lithium (7Li) if their mass is > 65 MJ. The minimum mass required to trigger sustained hydrogen-burning forms the upper limit of the definition currently used by the International Astronomical Union, while the deuterium-burning minimum mass of ~13 MJ forms the lower limit of the class, below which lie the planets.

It is also debated whether brown dwarfs would be better defined by their formation process rather than by theoretical mass limits based on nuclear fusion reactions. Under this interpretation brown dwarfs are those objects that represent the lowest-mass products of the star formation process, while planets are objects formed in an accretion disk surrounding a star. The coolest free-floating objects discovered such as WISE 0855, as well as the lowest-mass young objects known like PSO J318.5−22, are thought to have masses below 13 MJ, and as a result are sometimes referred to as planetary mass objects due to the ambiguity of whether they should be regarded as rogue planets or brown dwarfs. There are planetary mass objects known to orbit brown dwarfs, such as 2M1207b, MOA-2007-BLG-192Lb, and 2MASS J044144b.

Astronomers classify self-luminous objects by spectral class, a distinction intimately tied to the surface temperature, and brown dwarfs occupy types M, L, T, and Y. As brown dwarfs do not undergo stable hydrogen fusion they cool down over time, progressively passing through later spectral types as they age.

Video credit: NASA’s Goddard Space Flight Center/Scott Wiessinger (USRA): Animator/Scott Wiessinger (USRA): Producer/Ashley Balzer (ADNET): Science Writer/Claire Andreoli (NASA/GSFC): Public Affairs Officer