OrbitalHub

Wikipedia dixit:

“The Landsat program is the longest-running enterprise for acquisition of satellite imagery of Earth. On July 23, 1972 the Earth Resources Technology Satellite was launched. This was eventually renamed to Landsat. The most recent, Landsat 8, was launched on February 11, 2013. The instruments on the Landsat satellites have acquired millions of images. The images, archived in the United States and at Landsat receiving stations around the world, are a unique resource for global change research and applications in agriculture, cartography, geology, forestry, regional planning, surveillance and education, and can be viewed through the U.S. Geological Survey (USGS) ‘EarthExplorer’ website. Landsat 7 data has eight spectral bands with spatial resolutions ranging from 15 to 60 meters; the temporal resolution is 16 days. Landsat images are usually divided into scenes for easy downloading. Each Landsat scene is about 115 miles long and 115 miles wide (or 100 nautical miles long and 100 nautical miles wide, or 185 kilometers long and 185 kilometers wide).

[…] Landsat missions 1 through 5 carried the Landsat Multispectral Scanner (MSS), while missions 4 and 5 used the Landsat Thematic Mapper (TM) scanner. The Multispectral Scanner had a 230 mm (9 in) fused silica dinner-plate mirror epoxy bonded to three invar tangent bars mounted to base of a Ni/Au brazed Invar frame in a Serrurier truss that was arranged with four “Hobbs-Links” (conceived by Dr. Gregg Hobbs), crossing at mid-truss. This construct ensured the secondary mirror would simply oscillate about the primary optic axis to maintain focus despite vibration inherent from the 360 mm (14 in) beryllium scan mirror. This engineering solution allowed the United States to develop LANDSAT at least five years ahead of the French SPOT, which first used CCD arrays to stare without need for a scanner. However, LANDSAT data prices climbed from $250 per computer compatible data tape and $10 for black-and-white print to $4,400 for data tape and $2,700 for black-and-white print by 1984, making SPOT data a much more affordable option for satellite imaging data. This was a direct result of the commercialization efforts begun under the Carter administration, though finally completed under the Reagan administration.

The MSS FPA, or Focal Plane Array consisted of 24 square optical fibers extruded down to 0.005 mm (0.0002 in) square fiber tips in a 4×6 array to be scanned across the Nimbus spacecraft path in a ±6 degree scan as the satellite was in a 1.5 hour polar orbit, hence it was launched from Vandenberg Air Force Base. The fiber optic bundle was embedded in a fiber optic plate to be terminated at a relay optic device that transmitted fiber end signal on into six photodiodes and 18 photomultiplier tubes that were arrayed across a 7.6 mm (0.30 in) thick aluminum tool plate, with sensor weight balanced vs the 230 mm telescope on opposite side. This main plate was assembled on a frame, then attached to the silver-loaded magnesium housing with helicoil fasteners.

Key to the success of the multi spectral scanner was the scan monitor mounted on the underbelly of the magnesium housing. It consisted of a diode light source and a sensor mounted at the ends of four flat mirrors that were tilted so that it took 14 bounces for a beam to reflect the length of the three mirrors from source to sender. The beam struck the beryllium scan mirror seven times as it reflected seven times off the flat mirrors. The beam only sensed three positions, being both ends of scan and the mid scan, but by interpolating between these positions that was all that was required to determine where the multi spectral scanner was pointed. Using the scan monitor information the scanning data could be calibrated to display correctly on a map.”

Video credit: NASA Goddard

Wikipedia dixit:

“Parker Solar Probe is a planned NASA robotic spacecraft to probe the outer corona of the Sun. It will approach to within 8.5 solar radii (5.9 million kilometers or 3.67 million miles) to the ‘surface’ (photosphere) of the Sun. The project was announced as a new mission start in the fiscal 2009 budget year. On May 1, 2008 Johns Hopkins University Applied Physics Laboratory announced it will design and build the spacecraft, on a schedule to launch it in 2015. The launch date has since been pushed back to 2018, with the Delta IV Heavy as the launch vehicle. On May 31, 2017 the probe was renamed after solar astrophysicist Eugene Parker. According to NASA, this was the first time in history a space vessel was named after a living person.

The Parker Solar Probe mission design uses repeated gravity assists at Venus to incrementally decrease the orbital perihelion to achieve multiple passes of the Sun at approximately 8.5 solar radii, or about 6 million km (3.7 million mi; 0.040 AU). The mission is designed to survive the harsh environment near the Sun, where the incident solar intensity is approximately 520 times the intensity at Earth orbit, by the use of a solar shadow-shield. The solar shield, at the front of the spacecraft, is made of reinforced carbon-carbon composite. The spacecraft systems and scientific instruments are located in the shadow umbra of the shield, where direct light from the sun is fully blocked. The primary power for the mission will be by use of a dual system of photovoltaic arrays. A primary photovoltaic array, used for the portion of the mission outside 0.25 AU, is retracted behind the shadow shield during the close approach to the Sun, and a much smaller secondary array powers the spacecraft through closest approach. This secondary array uses pumped-fluid cooling to maintain operating temperature. As the probe passes around the Sun, it will achieve a velocity of up to 200 km/s (120 mi/s) making it by any measure, the fastest manmade object ever, almost three times faster than the current record holder, Helios 2.”

Video credit: NASA

Wikipedia dixit:

“Earth Observing-1 (EO-1) is a NASA Earth observation satellite created to develop and validate a number of instrument and spacecraft bus breakthrough technologies. These will enable the development of future Earth imaging observatories that will have a significant increase in performance while also having reduced cost and mass. The spacecraft is part of the New Millennium Program.

Its Advanced Land Imager (ALI) measures nine different wavelengths simultaneously, instead of the seven measured by the imager in Landsat 7. This permits a greater flexibility in false-color imagery. Another improvement is that instead of having an imaging spectrometer that sweeps from side to side, the ALI has a linear array of spectrometers that each scan a strip of ground parallel to that of adjacent spectrometers. In order to compare the two imagers, EO-1 follows Landsat 7 in its orbit by exactly one minute. Other new technologies include: Hyperion imaging spectrometer recording more than 200 wavelengths; phased array communications antenna; optical fiber cables connect the data logger with the two IBM RAD6000s; teflon-fueled pulsed plasma thruster; lightweight, flexible solar panel; carbon-coated radiators for thermal control; Linear Etalon Imaging Spectrometer Array equipped with a new atmospheric correction device.

EO-1 has also been used to test new software, like the Autonomous Sciencecraft Experiment. This allows the spacecraft to decide for itself how best to create a desired image. It is only limited by a priority list of different types of images, and by forecasts of cloud cover provided by the NOAA.

It was expected to function for twelve months and was designed to function for eighteen months. Those expectations were greatly exceeded however the hydrazine fuel was mostly depleted in February 2011. Small maneuvers have been successful for debris avoidance but long duration burns for orbit maintenance are not being performed due to insufficient fuel. EO-1 was deactivated on 30 March 2017. At its current altitude, it is estimated that the satellite will remain in orbit until the 2050s, when it will burn up in Earth’s atmosphere.”

Video credit: NASA Goddard

Wikipedia dixit:

“The Bigelow Expandable Activity Module (BEAM) is an experimental expandable space station module developed by Bigelow Aerospace, under contract to NASA, for testing as a temporary module on the International Space Station (ISS) from 2016 to 2018. It arrived at the ISS on April 10, 2016, was berthed to the station on April 16, and was expanded and pressurized on May 28, 2016.

NASA originally considered the idea of inflatable habitats in the 1960s, and developed the TransHab inflatable module concept in the late 1990s. The TransHab project was cancelled by Congress in 2000, and Bigelow Aerospace purchased the rights to the patents developed by NASA to pursue private space station designs. In 2006 and 2007, Bigelow launched two demonstration modules to Earth orbit, Genesis I and Genesis II.

NASA re-initiated analysis of expandable module technology for a variety of potential missions beginning in early 2010. Various options were considered, including procurement from commercial provider Bigelow Aerospace, for providing what in 2010 was proposed to be a torus-shaped storage module for the International Space Station. One application of the toroidal BEAM design was as a centrifuge demo preceding further developments of the NASA Nautilus-X multi-mission exploration concept vehicle. In January 2011, Bigelow projected that the BEAM module could be built and made flight-ready 24 months after a build contract was secured.

On December 20, 2012, NASA awarded Bigelow Aerospace a US$17.8 million contract to construct the Bigelow Expandable Activity Module under NASA’s Advanced Exploration Systems (AES) Program. Sierra Nevada Corporation built the $2 million Common Berthing Mechanism under a 16-month firm-fixed-price contract awarded in May 2013. NASA plans made public in mid-2013 called for a 2015 delivery of the module to the ISS. During a press event on March 12, 2015, at the Bigelow Aerospace facility in North Las Vegas, the completed ISS flight unit, compacted and with two Canadarm2 grapple fixtures attached, was displayed for the media.

The BEAM is an experimental program in an effort to test and validate expandable habitat technology. If BEAM performs favorably, it could lead to development of expandable habitation structures for future crews traveling in deep space. The two-year demonstration period will: demonstrate launch and deployment of a commercial inflatable module; implement folding and packaging techniques for inflatable shell; implement a venting system for inflatable shell during ascent to ISS; determine radiation protection capability of inflatable structures; demonstrate design performance of commercial inflatable structure like thermal, structural, mechanical durability, long term leak performance, etc.; demonstrate safe deployment and operation of an inflatable structure in a flight mission.

At the end of BEAM’s mission, the plan was to remove it from the ISS and burn up during reentry. On January 18, 2017, however, Bigelow and NASA announced they were discussing the possibility of extending the on-orbit life of BEAM and using it for other purposes.

BEAM is composed of two metal bulkheads, an aluminum structure, and multiple layers of soft fabric with spacing between layers, protecting an internal restraint and bladder system; it has neither windows nor internal power. The module was expanded about a month after being attached to the space station. It was inflated from its packed dimensions of 2.16 m (7.1 ft) long and 2.36 m (7.7 ft) in diameter to its pressurized dimensions of 4.01 m (13.2 ft) long and 3.23 m (10.6 ft) in diameter. The module has a mass of 1,413.0 kg (3,115.1 lb), and its interior pressure is 14.7 pounds per square inch (1 atm), the same as inside of the ISS.

BEAM’s internal dimensions provide 16 m3 (565 cu ft) of volume where a crew member will enter the module three to four times per year to collect sensor data, perform microbial surface sampling, conduct periodic change-out of the radiation area monitors, and inspect the general condition of the module. The hatch to the module will otherwise remain closed. Its interior is described as being “a large closet with padded white walls”, with various equipment and sensors attached to two central supports.”

Video credit: NASA/ESA

ESA dixit:

“SmallGEO is a multipurpose satellite platform capable of accommodating a wide range of commercial telecommunications payloads and missions, from TV broadcasting to multimedia applications, Internet access and mobile or fixed services in a wide range of frequency bands.

Its new, modular and flexible design boosts European industry’s ability to play a significant role in commercial satcoms by easing entry into the lower-mass telecom satellite market.

The platform was developed by OHB System (DE) under ESA’s Advanced Research in Telecommunication Systems (ARTES) programme. SmallGEO is the first ESA programme with OHB System AG as the industrial prime. Its first flight and in-orbit demonstration will be with the Hispasat 36W-1 telecom satellite.”

Video credit: ESA

Wikipedia dixit:

“The Interplanetary Transport System (ITS), formerly known as the Mars Colonial Transporter (MCT), is SpaceX’s privately funded development project to design and build a spaceflight system of reusable rocket engines, launch vehicles and spacecraft to transport humans to Mars and return to Earth. SpaceX began development of the large Raptor rocket engine for the Mars Colonial Transporter before 2014. As of June 2016, publicly-announced company conceptual plans included the first Mars-bound cargo flight of ITS launching no earlier than 2022, followed by the first ITS Mars flight with passengers one synodic period later in 2024, following two preparatory research launches of Mars probes in 2018 and 2020 on Dragon/Falcon Heavy equipment. SpaceX CEO Elon Musk unveiled details of the space mission architecture at the 67th International Astronautical Congress on 27 September 2016. The booster will have a diameter of 12 m, the spaceship diameter will be 17 m and stack height of the entire vehicle will be 122 m. The selected fuel type is deep-cryo methalox for 42 Raptor engines on the booster and 9 on the spacecraft.

As early as 2007, Elon Musk stated a personal goal of eventually enabling human exploration and settlement of Mars. Bits of additional information about the mission architecture were released in 2011–2015, including a 2014 statement that initial colonists would arrive at Mars no earlier than the middle of the 2020s. Company plans as of mid-2016 continue to call for the arrival of the first humans on Mars no earlier than 2025.

Musk stated in a 2011 interview that he hoped to send humans to Mars’ surface within 10–20 years, and in late 2012 he stated that he envisioned a Mars colony of tens of thousands with the first colonists arriving no earlier than the middle of the 2020s. In October 2012, Musk articulated a high-level plan to build a second reusable rocket system with capabilities substantially beyond the Falcon 9/Falcon Heavy launch vehicles on which SpaceX had by then spent several billion US dollars. This new vehicle was to be “an evolution of SpaceX’s Falcon 9 booster… much bigger [than Falcon 9].” But Musk indicated that SpaceX would not be speaking publicly about it until 2013. In June 2013, Musk stated that he intended to hold off any potential IPO of SpaceX shares on the stock market until after the “Mars Colonial Transporter is flying regularly.”

In February 2014, Musk stated that Mars Colonial Transporter will be “100 times the size of an SUV”, and capable of taking 100 tons of cargo to Mars. Also, SpaceX engine development head Tom Mueller said SpaceX would use nine Raptor engines on a single rocket, similar to the use of nine Merlin engines on each Falcon 9 booster core. He said “It’s going to put over 100 tons of cargo on Mars.” In early 2014, it appeared that the large rocket core that would be used for the booster to be used with MCT would be at least 10 meters (33 ft) in diameter, nearly three times the diameter and over seven times the cross-sectional area of the Falcon 9 booster cores. In August 2014, media sources speculated that the initial flight test of the Raptor-driven super-heavy launch vehicle could occur as early as 2020, in order to fully test the engines under orbital spaceflight conditions; however, any colonization effort was reported to continue to be “deep into the future”.

In January 2015, Musk said that he hoped to release details of the “completely new architecture” for the Mars transport system in late 2015 but those plans changed and, by December 2015, the plan to publicly release additional specifics had moved to 2016. In January 2016, Musk indicated that he hoped to describe the architecture for the Mars missions with the next generation SpaceX rocket and spacecraft later in 2016, at the 67th International Astronautical Congress conference, in September 2016. Musk stated in June 2016 that the first unmanned MCT Mars flight was planned for departure in 2022, to be followed by the first manned MCT Mars flight departing in 2024. By September 2016, Musk noted that the MCT name would not continue, as the system would be able to “go well beyond Mars”, and that a new name would be needed: Interplanetary Transport System (ITS), with the first spacecraft named “Heart of Gold” in reference to the Infinite Improbability Drive.”

Video credit: SpaceX