OrbitalHub

NASA dicit:

As a planet moves around its host star, it exerts a tiny gravitational tug that shifts the star’s position a bit. This can pull the distant star closer and farther from a perfect alignment. Since the nearer star acts as a natural lens, it’s like the distant star’s light will be pulled slightly in and out of focus by the orbiting planet. By picking out little shudders in the starlight, astronomers will be able to infer the presence of planets.

Xallarap is parallax spelled backward. Parallax relies on motion of the observer – Earth moving around the Sun – to produce a change in the alignment between the distant source star, the closer lens star and the observer. Xallarap works the opposite way, modifying the alignment due to the motion of the source.

While microlensing is generally best suited to finding worlds farther from their star than Venus is from the Sun, the xallarap effect works best with very massive planets in small orbits, since they make their host star move the most. Revealing more distant planets will also allow us to probe a different population of worlds.

Video credit: NASA

NASA dicit:

Before Artemis astronauts land on the Moon in 2024, robots will scout the surface for resources and collect information about the lunar South Pole. Some landers and rovers will come equipped with handy tools, including drills and chemical analyzers, to examine what lies below the lunar surface.

The Polar Resources Ice Mining Experiment-1 (PRIME-1) will be the first in-situ resource utilization demonstration on the Moon. Additionally, for the first time, NASA will robotically sample and analyze for ice from below the surface.

Video credit: NASA

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, 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, all engines will be discarded into the Atlantic ocean. On initial flights, these discarded units will be historic Shuttle engines.

Video credit: NASA’s Stennis Space Center

NASA dicit:

Globular clusters are extremely dense stellar systems, which host stars that are closely packed together. These systems are also typically very old — the globular cluster at the focus of this study, NGC 6397, is almost as old as the universe itself. This cluster resides 7,800 light-years away, making it one of the closest globular clusters to Earth. Due to its very dense nucleus, it is known as a core-collapsed cluster.

At first, astronomers thought the globular cluster hosted an intermediate-mass black hole. These are the long-sought “missing link” between supermassive black holes (many millions of times our Sun’s mass) that lie at the cores of galaxies, and stellar-mass black holes (a few times our Sun’s mass) that form following the collapse of a single massive star. Their mere existence is hotly debated. Only a few candidates have been identified to date.

The researchers used previous estimates of the stars’ tiny proper motions (their apparent motions on the sky), which allow for determining their true velocities within the cluster. These precise measurements for stars in the cluster’s core could only be made with Hubble over several years of observation. The Hubble data were added to well-calibrated proper motion measurements provided by the European Space Agency’s Gaia space observatory which are less precise than Hubble’s observations in the core.

Video credit: NASA’s Goddard Space Flight Center/Paul Morris: Lead Producer/Music: “Glass Ships” by Chris Constantinou [PRS] and Paul Frazer [PRS] via Killer Tracks [BMI] and Universal Production Music/Visual Credits: Artist’s Impression of the Black Hole Concentration in NGC 6397/Video credit: ESA/Hubble, N. Bartmann/Callout of the Black Hole Concentration in NGC 6397/Video credit: ESA/Hubble, N. Bartmann/Artist Rendition of Gaia Spacecraft/Image credit: ESA, C. Carreau

Northrop Grumman dicit:

SpaceLogistics LLC, a Northrop Grumman Company, has partnered with DARPA on the agency’s Robotic Servicing of Geosynchronous Satellites (RSGS) program.

The groundbreaking mission features the first-ever commercial robotic servicing spacecraft, known as the Mission Robotic Vehicle (MRV), and aims to expand the market for satellite servicing with advanced robotics technology.

The company is also developing Mission Extension Pods (MEPs) to be installed by the MRV. The new pods act in place of the propulsion system of aging satellites and provide six years of life extension.

Video credit: Northrop Grumman

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