OrbitalHub

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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:

Concerning the lunar month of approximately 29.53 days as viewed from Earth, the lunar phase or Moon phase is the shape of the Moon’s directly sunlit portion, which can be expressed quantitatively using areas or angles, or described qualitatively using the terminology of the four major phases (new moon, first quarter, full moon, last quarter) and four minor phases (waxing crescent, waxing gibbous, waning gibbous, and waning crescent).

The lunar phases gradually change over a synodic month (c. 29.53 days) as the orbital positions of the Moon around Earth, and Earth around the Sun, shift. The visible side of the Moon is variously sunlit, depending on the position of the Moon in its orbit, with the sunlit portion varying from 0% (at new moon) to 100% (at full moon).

Each of the four major lunar phases is approximately 7.4 days±19 hours (6.58–8.24 days), the variation being due to the elliptical shape of the Moon’s orbit.

There are four principal (primary, or major) lunar phases: the new moon, first quarter, full moon, and last quarter (also known as third or final quarter), when the Moon’s ecliptic longitude is at an angle to the Sun (as viewed from the center of the Earth) of 0°, 90°, 180°, and 270° respectively. Each of these phases appears at slightly different times at different locations on Earth, and tabulated times are therefore always geocentric (calculated for the Earth’s center).

Between the principal phases are intermediate phases, during which the Moon’s apparent shape is either crescent or gibbous. On average, the intermediate phases last one-quarter of a synodic month, or 7.38 days.

The term waxing is used for an intermediate phase when the Moon’s apparent shape is thickening, from new to a full moon; and waning when the shape is thinning. The duration from full moon to new moon (or new moon to full moon) varies from approximately 13 days 22+1⁄2 hours to about 15 days 14+1⁄2 hours.

A new moon appears highest on the summer solstice and lowest on the winter solstice. A first quarter moon appears highest on the spring equinox and lowest on the autumn equinox. A full moon appears highest on the winter solstice and lowest on the summer solstice. A last quarter moon appears highest on the autumn equinox and lowest on the spring equinox.

Credit: NASA Goddard

Wikipedia dicit:

A neutron star is the collapsed core of a massive supergiant star, which had a total mass of between 10 and 25 solar masses, possibly more if the star was especially metal-rich. Except for black holes and some hypothetical objects (e.g. white holes and quark stars), neutron stars are the smallest and densest currently known class of stellar objects. Neutron stars have a radius on the order of 10 kilometres (6 mi) and a mass of about 1.4 solar masses. They result from the supernova explosion of a massive star, combined with gravitational collapse, that compresses the core past white dwarf star density to that of atomic nuclei.

Once formed, they no longer actively generate heat and cool over time; however, they may still evolve further through collision or accretion. Most of the basic models for these objects imply that neutron stars are composed almost entirely of neutrons (subatomic particles with no net electrical charge and with slightly larger mass than protons); the electrons and protons present in normal matter combine to produce neutrons at the conditions in a neutron star. Neutron stars are partially supported against further collapse by neutron degeneracy pressure, a phenomenon described by the Pauli exclusion principle, just as white dwarfs are supported against collapse by electron degeneracy pressure. However, neutron degeneracy pressure is not by itself sufficient to hold up an object beyond 0.7 M☉ and repulsive nuclear forces play a larger role in supporting more massive neutron stars. If the remnant star has a mass exceeding the Tolman–Oppenheimer–Volkoff limit of around 2 solar masses, the combination of degeneracy pressure and nuclear forces is insufficient to support the neutron star. It continues collapsing to form a black hole. The most massive neutron star detected so far, PSR J0952–0607, is estimated to be 2.35±0.17 solar masses.

Neutron stars that can be observed are very hot and typically have a surface temperature of around 600000 K. Neutron star material is remarkably dense: a normal-sized matchbox containing neutron-star material would have a weight of approximately 3 billion tonnes, the same weight as a 0.5 cubic kilometre chunk of the Earth (a cube with edges of about 800 metres) from Earth’s surface. Their magnetic fields are between 108 and 1015 (100 million and 1 quadrillion) times stronger than Earth’s magnetic field. The gravitational field at the neutron star’s surface is about 2×1011 (200 billion) times that of Earth’s gravitational field.

Credit: NASA Goddard

Wikipedia dicit:

Transiting Exoplanet Survey Satellite (TESS, Explorer 95 or MIDEX-7) is a space telescope for NASA’s Explorer program, designed to search for exoplanets using the transit method in an area 400 times larger than that covered by the Kepler mission. It was launched on 18 April 2018, atop a Falcon 9 launch vehicle and was placed into a highly elliptical 13.70-day orbit around the Earth. The first light image from TESS was taken on 7 August 2018, and released publicly on 17 September 2018.

Over the course of the two-year primary mission, TESS was expected to ultimately detect about 1,250 transiting exoplanets orbiting the targeted stars, and an additional 13,000 transiting planets orbiting additional stars in the fields that TESS would observe. As of 5 November 2022, TESS had identified 5,969 candidate exoplanets, of which only 268 had been confirmed and 1720 had been dismissed as false positives. After the end of the primary mission around 4 July 2020, data from the primary mission continue to be searched for planets, while the extended missions continues to acquire additional data.

The primary mission objective for TESS was to survey the brightest stars near the Earth for transiting exoplanets over a two-year period. The TESS satellite uses an array of wide-field cameras to perform a survey of 85% of the sky. With TESS, it is possible to study the mass, size, density and orbit of a large cohort of small planets, including a sample of rocky planets in the habitable zones of their host stars. TESS provides prime targets for further characterisation by the James Webb Space Telescope (JWST), as well as other large ground-based and space-based telescopes of the future. While previous sky surveys with ground-based telescopes have mainly detected giant exoplanets and the Kepler space telescope has mostly found planets around distant stars that are too faint for characterisation, TESS finds many small planets around the nearest stars in the sky. TESS records the nearest and brightest main sequence stars hosting transiting exoplanets, which are the most favourable targets for detailed investigations. By providing such detailed information about planetary systems with hot Jupiters, TESS makes it possible to better understand the architecture of such systems.

Credit: NASA Goddard

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