NASA Remembers Skylab Astronaut Gerald Carr

NASA logo.

Aug. 26, 2020

Astronaut Gerald Carr, who commanded the last Skylab mission, died Aug. 26, 2020.

“NASA and the nation have lost a pioneer of long duration spaceflight," said NASA Administrator Jim Bridenstine. "We send our condolences to the family and loved ones of astronaut Gerald 'Jerry' Carr, whose work provided a deeper understanding of life on Earth and in space.

Astronaut portrait of Gerald Carr. Image Credits: NASA

“A colonel in the U.S. Marine Corps, Carr was a test pilot who logged more than 5,300 hours of jet flying time on aircraft including the F-9, F-6A Skyray, and F-8 Crusader. A naval aviator selected for the astronaut class in 1966, he served as Capcom for Apollos 8 and 12 and broke spaceflight duration records on Skylab 4, the final mission to the orbital workshop.

“Recalling the view back to Earth, Carr credited his Skylab crewmate Edward Gibson with the observation that, from space, ‘You can see no boundaries on the Earth, no man-made boundaries, that the barriers that man puts up between himself and his fellow man, that the only boundaries you can see are the natural ones, the rivers, the lakes, things like that.’

“We remember and honor his life and his contributions to the nation.”

Carr's family also issued a statement, saying, “Throughout his life and career, Jerry Carr was the epitome of an officer and a gentleman. He loved his family, he loved his country and he loved to fly. We are all enormously proud of his legacy as a true space pioneer and of the lasting impact of his historic mission aboard America’s first space station. We will remember him most as a devoted husband, father, brother, grandfather and great grandfather. We will miss him greatly.”

For more information about Carr’s NASA career:

https://www.nasa.gov/sites/default/files/atoms/files/carr_gerald_0.pdf

Image (mentioned), Text, Credits: NASA/Brian Dunbar.

R.I.P. ; Orbiter.ch

Where Are Stars Made? NASA's Spitzer Spies a Hot Spot

NASA - Spitzer Space Telescope patch.

August 26, 2020

The most massive stars in the universe are born inside cosmic clouds of gas and dust, where they leave behind clues about their lives for astronomers to decode.

Image above: The star-forming nebula W51 is one of the largest "star factories" in the Milky Way galaxy. Interstellar dust blocks the visible light emitted by the region, but it is revealed by NASA's Spitzer Space Telescope, which captures infrared light that can penetrate dust clouds. Image Credits: NASA/JPL-Caltech.

The nebula known as W51 is one of the most active star-forming regions in the Milky Way galaxy. First identified in 1958 by radio telescopes, it makes a rich cosmic tapestry in this image from NASA's recently retired Spitzer Space Telescope.

Located about 17,000 light-years from Earth, in the direction of the constellation Aquila in the night sky, W51 is about 350 light-years - or about 2 quadrillion miles - across. It is almost invisible to telescopes that collect visible light (the kind human eyes detect), because that light is blocked by interstellar dust clouds that lie between W51 and Earth. But longer wavelengths of light, including radio and infrared, can pass unencumbered through the dust. When viewed in infrared by Spitzer, W51 is a spectacular sight: Its total infrared emission is the equivalent of 20 million Suns.

If you could see it with your naked eye, this dense cloud of gas and dust would appear about as large as the full Moon. The Orion Nebula - another well-known star-forming region and a favorite observing target for amateur astronomers - occupies about the same size area in the sky. But W51 is actually much farther from Earth than Orion and thus much larger, and it's about 75 times more luminous. While Orion contains four known O-type stars - the most massive stars in the universe - W51 contains over 30.

"Star factories" like this one can operate for millions of years. The cavernous red region on the right side of W51 is older, evident in the way it has already been carved out by winds from generations of massive stars (those at least 10 times the mass of our Sun). The dust and gas in the region are swept around even more when those stars die and explode as supernovas. On the nebula's younger left side, many stars are just beginning to clear away the gas and dust in the same way the stars in the older region have done. It's apparent that many of these young stars are in the process of forming bubbles of empty space around themselves.

This image was taken as part of a major observation campaign by Spitzer in 2004 to map the large-scale structure of the Milky Way galaxy - a considerable challenge because Earth lies inside it. Called the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE), the survey also turned up valuable data on many wonders within the Milky Way, including images of multiple stellar factories like W51 that were hidden by dust from visible-light observatories.

"The really spectacular images provided by Spitzer via the GLIMPSE survey ­- in concert with data from many other, complementary telescopes - give us insight into how massive stars form in our Milky Way, and then how their powerful winds and radiation interact with the remaining ambient material," said Breanna Binder, an assistant professor of physics and astronomy at California State Polytechnic University, Pomona, who studies the life cycles of massive stars. "We can't observe star-forming regions in other galaxies in anywhere near the level of detail that we can in our own galaxy. So regions like W51 are really important for advancing our understanding of star formation in the Milky Way, which we can then extrapolate to how star formation proceeds in other, nearby galaxies."

Spitzer Space Telescope. Animation Credit: NASA

NASA's Spitzer Space Telescope launched 17 years ago this week, on Aug. 25, 2003. The spacecraft was retired on Jan. 30, 2020. Though the mission has concluded, the entire body of scientific data collected by Spitzer during its lifetime is available to the public via the Spitzer data archive, housed at the Infrared Science Archive at IPAC at Caltech in Pasadena, California.

NASA's Jet Propulsion Laboratory, a division of Caltech, managed Spitzer mission operations for NASA's Science Mission Directorate in Washington. Science operations were conducted at the Spitzer Science Center at IPAC at Caltech. Spacecraft operations were based at Lockheed Martin Space in Littleton, Colorado.

Spitzer Space Telescope: http://www.nasa.gov/mission_pages/spitzer/main/index.html

Image (mentioned), Animation (mentioned), Text, Credits: NASA/JPL/Calla Cofield.

Greetings, Orbiter.ch

LHCb discovers first “open-charm” tetraquark

CERN - European Organization for Nuclear Research logo.

25 August, 2020

The particle, which has been called X(2900), was detected by analysing all the data LHCb has recorded so far from collisions at CERN’s Large Hadron Collider 

Image above: An artist’s impression of the new tetraquark showing the individual constituent particles (Image: Daniel Dominguez/CERN).

The LHCb experiment at CERN has developed a penchant for finding exotic combinations of quarks, the elementary particles that come together to give us composite particles such as the more familiar proton and neutron. In particular, LHCb has observed several tetraquarks, which, as the name suggests, are made of four quarks (or rather two quarks and two antiquarks). Observing these unusual particles helps scientists advance our knowledge of the strong force, one of the four known fundamental forces in the universe. At a CERN seminar held virtually on 12 August, LHCb announced the first signs of an entirely new kind of tetraquark with a mass of 2.9 GeV/c²: the first such particle with only one charm quark.

First predicted to exist in 1964, scientists have observed six kinds of quarks (and their antiquark counterparts) in the laboratory: up, down, charm, strange, top and bottom. Since quarks cannot exist freely, they group to form composite particles: three quarks or three antiquarks form “baryons” like the proton, while a quark and an antiquark form “mesons”.

The LHCb detector at the Large Hadron Collider (LHC) is devoted to the study of B mesons, which contain either a bottom or an antibottom. Shortly after being produced in proton–proton collisions at the LHC, these heavy mesons transform – or “decay” – into a variety of lighter particles, which may undergo further transformations themselves. LHCb scientists observed signs of the new tetraquark in one such decay, in which the positively charged B meson transforms into a positive D meson, a negative D meson and a positive kaon: B⁺→D⁺D⁻K⁺. In total, they studied around 1300 candidates for this particular transformation in all the data the LHCb detector has recorded so far.

The well-established quark model predicts that some of the D⁺D⁻ pairs in this transformation could be the result of intermediate particles – such as the ψ(3770) meson – that only manifest momentarily: B⁺→ψ(3770)K⁺→D⁺D⁻K⁺. However, theory does not predict meson-like intermediaries resulting in a D⁻K⁺ pair. LHCb were therefore surprised to see a clear band in their data corresponding to an intermediate state transforming into a D⁻K⁺ pair at a mass of around 2.9 GeV/c², or around three times the mass of a proton.

Graphic above: The band associated with the new tetraquark transforming into a D⁻ and a K⁺ at a mass of 2.9 GeVc² (Image: LHCb Collaboration/CERN).

The data have been interpreted as the first sign of a new exotic state of four quarks: an anticharm, an up, a down and an antistrange (c̄uds̄). All previous tetraquark-like states observed by LHCb always had a charm–anticharm pair, resulting in net-zero “charm flavour”. The newly observed state is the first time a tetraquark containing a sole charm has been seen, which has been dubbed an “open-charm” tetraquark.

“When we first saw the excess in our data, we thought there was a mistake,” says Dan Johnson, who led the LHCb analysis. “After years of analysing the data, we accepted that there really is something surprising!”

Why is this important? It so happens that the jury is still out as to what a tetraquark really is. Some theoretical models favour the notion that tetraquarks are pairs of distinct mesons bound together temporarily as a “molecule”, while other models prefer to think of them as a single cohesive unit of four particles. Identifying new kinds of tetraquarks and measuring their properties – such as their quantum spin (their intrinsic spatial orientation) and their parity (how they appear under a mirror-like transformation) – will help paint a clearer picture of these exotic inhabitants of the subatomic domain. Johnson adds: “This discovery will also allow us to stress-test our theories in an entirely new domain.”

Large Hadron Collider (LHC). Animation Credit: CERN

While LHCb’s observation is an important first step, more data will be needed to verify the nature of the structure observed in the B⁺ decay. The LHCb collaboration will also anticipate independent verification of their discovery from other dedicated B-physics experiments such as Belle II. Meanwhile, the LHC continues to provide new and exciting results for experimentalists and theorists alike to dig into.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 23 Member States.

Related links:

Read more about the result on the LHCb website: https://lhcb-public.web.cern.ch/#Tcs

Watch the recording of the CERN seminar: https://cds.cern.ch/record/2727788

Download the presentation given at the seminar: https://indico.cern.ch/event/900975/attachments/2084266/3505641/20-08Aug-11_DanJohnson.pdf

LHCb experiment at CERN: https://home.cern/science/experiments/lhcb

CERN seminar held virtually on 12 August: https://indico.cern.ch/event/900975/

Large Hadron Collider (LHC): https://home.cern/science/accelerators/large-hadron-collider

Belle II: https://www.belle2.org/

For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/

Image (mentioned), Graphic (mentioned), Animation (mentioned), Text, Credits: European Organization for Nuclear Research (CERN)/Achintya Rao.

Best regards, Orbiter.ch

LS2 Report: CERN’s newest accelerator awakens

CERN - European Organization for Nuclear Research logo.

25 August, 2020

Linac 4 has taken over from the retired Linac 2 as the first accelerator in the LHC injection chain

Image above: Linac 4 is the newest accelerator to join CERN’s complex (Image: Andrew Hara/CERN).

The CERN Control Centre (CCC) is abuzz once again. The second long shutdown (LS2) has come to an end for CERN’s newest accelerator – Linac 4 – and the accelerator complex’s slow awakening from a two-year repair-and-recuperation hibernation has begun. The three-week machine-development run until mid-August saw low-energy beams of negative hydrogen ions (H⁻) fly through the first part of the accelerator for the first time since it was connected to the PS Booster. On 20 August, the first beams at the nominal energy of 160 MeV were accelerated through the entire machine and into a dedicated beam dump located at the end of the linac. Over the coming months, the brand-new accelerator will finish being commissioned and will be made ready to deliver various beams to the PS Booster in December.

CERN is famous for its circular accelerators, in particular the 27-kilometre-circumference Large Hadron Collider. But the protons that circulate in these bigger machines first undergo acceleration in a humble and relatively small linear accelerator, or linac. In 2018, Linac 2, which had fed protons to CERN’s accelerator complex since 1978, was finally retired, with the 86-metre-long Linac 4 ready to take its place. But a new machine comes with new challenges for the team operating it.

The machine-development phase from late July was handled by the Accelerators and Beam Physics group (ABP) team responsible for the proton sources, who previously also ran the Linac 2 operations. “ABP made sure that we could send beam through the first structure in Linac 4, the so-called radio-frequency quadrupole or RFQ, with low beam losses,” notes Bettina Mikulec, who is leading the team from the Operations group (OP) who are responsible not only for Linac 4 but for the PS Booster as well. Over the three weeks, ABP also worked on optimising the proton source and realigning it to get a better angle for the particles entering the RFQ. ABP then handed over the accelerator for commissioning to the team from OP.

CERN’s newest accelerator awakens

Video above: (Video: CERN).

Linac 4 differs significantly in behaviour from its predecessor, in terms of shaping the profile of the proton beams that are fired downstream. “With Linac 4, we can adjust additional parameters of the beam so we can feed the Booster in a loss-free process,” adds Mikulec. “We can also adapt the energy spread of the beams to match the Booster’s acceptance, whereas with Linac 2 one practically only adjusted the length of the beam before injection.” The newer accelerator will inject particles into the PS Booster at an energy of 160 MeV, significantly higher than the 50-MeV operation of Linac 2. This enables the Booster in turn to inject beams at an energy of 2 GeV into the Proton Synchrotron (PS), higher than the previous value of 1.4 GeV.

The commissioning phase is crucial for long-term operation of Linac 4. Qualifying the equipment, optimising beam instrumentation and much more can only be done with beam in the accelerator. This week, Linac 4 was phased in for operation at its maximum energy. “Among other things, we are working with ABP to verify the optics of the machine to provide the optimum conditions for the PS Booster’s injection point,” Mikulec points out.

The beams are now being sent to Linac 4’s dedicated beam dump, and from September onwards will be sent down the injection line towards the PS Booster before slamming into the beam dump located just upstream of the Booster. The Linac 4 team are back in full operation and look forward to delivering beam into the PS Booster on 7 December.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 23 Member States.

Related links:

The second long shutdown (LS2): https://home.cern/tags/long-shutdown-2

Linac 4: https://home.cern/science/accelerators/linear-accelerator-4

PS Booster: https://home.cern/science/accelerators/proton-synchrotron-booster

Proton Synchrotron (PS): https://home.cern/science/accelerators/proton-synchrotron

Large Hadron Collider (LHC): https://home.cern/science/accelerators/large-hadron-collider

For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/

Image (mentioned), Video (mentioned), Text, Credits: European Organization for Nuclear Research (CERN)/Achintya Rao.

Best regards, Orbiter.ch

Bavi – Northwestern Pacific Ocean

NASA - EOS Terra Mission patch.

August 25, 2020

Bavi – Northwestern Pacific Ocean

Aug. 25, 2020 – NASA Finds Typhoon Bavi’s Strongest Side

As Typhoon Bavi continued tracking north through the Yellow Sea, NASA’s Terra satellite used infrared light to identify strongest storms and coldest cloud top temperatures. The temperature data revealed that the strongest storms were not totally surrounding the eye.

Image above: On Aug. 25 at 10:25 a.m. EDT (1425 UTC), the MODIS instrument aboard NASA’s Terra satellite gathered temperature information about Hurricane Bavi’s cloud tops. MODIS found the most powerful thunderstorms (red) were west and south of the eyewall, where temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 Celsius). Image Credits: NASA/NRL.

Infrared Data Reveals Powerful Storms

On Aug. 25 at 10:25 a.m. EDT (1425 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Terra satellite gathered temperature information about Bavi’s cloud tops. Infrared data provides temperature information, and the strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.

NASA's EOS Terra satellite. Image Credit: NASA

MODIS found the most powerful thunderstorms were west and south of the eyewall, where temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 Celsius). Cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall. Satellite data also showed that the eye was about 15 nautical miles wide.

Bavi’s Status 

At 11 a.m. EDT (1500 UTC) on Aug. 25, Typhoon Bavi was centered near latitude 30.6 degrees north and longitude 125.2 degrees east, about 274 nautical miles west-southwest of Sasebo, Japan. Bavi was moving to the north-northwest and had maximum sustained winds 95 knots (109 mph/176 kph).

Bavi is forecast to continue tracking in a northerly direction, moving through the Yellow Sea. It is expected to make landfall in extreme northwestern North Korea around Aug. 27 at 0000 UTC (Aug. 26 at 8 p.m. EDT).

NASA Researches Tropical Cyclones

Tropical cyclones/hurricanes are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

NASA’s Terra satellite: http://www.nasa.gov/mission_pages/terra/index.html

Text, Credits: NASA/Lynn Jenner/Goddard Space Flight Center, by Rob Gutro.

Greetings, Orbiter.ch

Latest NASA News on Storms Laura & Marco

NASA - EOS Terra Mission patch / NOAA & NASA - Suomi NPP Mission patch.

August 25, 2020

Laura – Atlantic Ocean

Aug. 25, 2020 – NASA Gathers Nighttime Images of Laura Becoming a Hurricane

Tropical Storm Laura strengthened to a hurricane in the morning hours of Aug. 25, and NASA provided infrared imagery that showed the structure, temperature and rainmaking capabilities of the storm. When NASA’s Terra satellite and NASA-NOAA’s Suomi NPP satellite passed overhead, both provided different images of Laura as it was about to exit the Caribbean Sea and move into the Gulf of Mexico.

Image above: On Aug. 25 at 12:35 a.m. EDT (0435 UTC) the MODIS instrument that flies aboard NASA’s Terra satellite revealed the most powerful thunderstorms (yellow) were around Laura’s center where cloud top temperatures were as cold as minus 80 degrees Fahrenheit (minus 62.2 Celsius). Those storms were over the Caribbean Sea, just south of western Cuba. Strong storms (red) with cloud top temperatures as cold as minus 70 degrees Fahrenheit (minus 56.6. degrees Celsius) surrounded the center and were generating large amounts of rain. Image Credits: NASA/NRL.

Watches and Warnings on Aug. 25

On Aug. 25, NOAA’s National Hurricane Center (NHC) posted several watches and warnings.

A Storm Surge Warning is in effect from San Luis Pass Texas to the mouth of the Mississippi River, including areas inside the Port Arthur Hurricane Flood Protection system. A Hurricane Warning is in effect from San Luis Pass, Texas to Intracoastal City, Louisiana.

A Tropical Storm Warning is in effect from Sargent, Texas to San Luis Pass and from east of Intracoastal City to the mouth of the Mississippi River. A Storm Surge Watch is in effect from Freeport, Texas to San Luis Pass.

NASA’s Night-Time View of Laura’s Intensification

Image above: NASA-NOAA’s Suomi NPP satellite passed the Caribbean Sea early on Aug. 25 and captured a nighttime image of Tropical Storm Laura. Not yet named a hurricane, the development of an eye was apparent. Image Credits: NASA Worldview, Earth Observing System Data and Information System (EOSDIS).

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a nighttime image of Laura during the early morning hours of Aug. 25. Not yet named a hurricane, the development of an eye was apparent. By 11 a.m. EDT, Laura had a central dense overcast and some outer banding in the southern quadrant.

Satellite imagery shows the storm is over 350 miles in diameter. Hurricane-force winds extend outward up to 45 miles (75 km) from the center and tropical-storm-force winds extend outward up to 175 miles (280 km).

NASA’s Infrared Data Reveals Heavy Rainmakers

Tropical cyclones are made up of hundreds of thunderstorms, and infrared data can show where the strongest storms are located. That is because infrared data provides temperature information, and the strongest thunderstorms that reach highest into the atmosphere have the coldest cloud top temperatures.

On July 27 at 4:35 a.m. EDT (0835 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Aqua satellite used infrared light to analyze the strength of storms within Laura. MODIS found the most powerful thunderstorms were around Laura’s center over the Caribbean Sea, just south of western Cuba, where cloud top temperatures were as cold as minus 80 degrees Fahrenheit (minus 62.2 Celsius). NASA research has found that cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall.

Strong storms with cloud top temperatures as cold as minus 70 degrees Fahrenheit (minus 56.6. degrees Celsius) circled the most powerful storms, and were also dropping large amounts of rain.

Animation above: NASA-NOAA’s Suomi NPP satellite provided visible imagery of Tropical Storm Laura’s movement in the Atlantic Ocean from Aug. 21 to 24. It affected the Northern Leeward Islands, Puerto Rico, Hispaniola, Jamaica and Cuba before moving into the Gulf of Mexico on Aug. 25. Animation Credits: NASA Worldview, Earth Observing System Data and Information System (EOSDIS).

Laura’s Status on Aug. 25, 2020

At 11 a.m. EDT (1500 UTC), the center of Hurricane Laura was located near latitude 23.7 degrees north and longitude 87.0 degrees west. That is about 585 miles (940 km) southeast of Lake Charles, Louisiana and about 620 miles (1,000 km) southeast of Galveston, Texas.

Laura was moving toward the west-northwest near 16 mph (26 kph), and this general motion should continue today, according to NHC. A turn toward the northwest is forecast by Wednesday, and a northwestward to north-northwestward motion should continue through Wednesday night. Reports from NOAA and Air Force Reserve Hurricane Hunter aircraft indicate that maximum sustained winds are near 75 mph (120 kph) with higher gusts. The estimated minimum central pressure based on the Hurricane Hunter aircraft data is 990 millibars.

Laura’s Forecast from NHC

Significant strengthening is forecast during the next 36 hours, and Laura is expected to be a major hurricane at landfall. NHC noted the forecast calls for the hurricane to make landfall in the area of southwestern Louisiana or the upper Texas coast late Wednesday night or Thursday morning.

About NASA’s EOSDIS Worldview

NASA’s Earth Observing System Data and Information System (EOSDIS) Worldview application provides the capability to interactively browse over 700 global, full-resolution satellite imagery layers and then download the underlying data. Many of the available imagery layers are updated within three hours of observation, essentially showing the entire Earth as it looks “right now.”

NASA Researches Earth from Space

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America’s leadership in space and scientific exploration.

For updated forecasts, visit: http://www.nhc.noaa.gov/

NASA’s Terra satellite: http://www.nasa.gov/mission_pages/terra/index.html

Text, Credits: NASA/Lynn Jenner/Goddard Space Flight Center, by Rob Gutro.

Marco (was TD14) – Atlantic Ocean

Aug. 25, 2020 – NASA’s Terra Satellite Catches the Demise of Post-Tropical Cyclone Marco

NASA’s Terra satellite passed over the Gulf of Mexico early on Aug. 25 and found a very small area of convection from post-tropical cyclone Marco, northeast of its center. All watches and warnings have been dropped as the storm continues to weaken toward dissipation.

Image above: On Aug. 25 at 12:30 a.m. EDT (0430 UTC), the MODIS instrument that flies aboard NASA’s Terra satellite gathered infrared data on post-tropical cyclone Marco that showed a small area of storms where cloud top temperatures were as cold as minus 50 degrees Fahrenheit (minus 45.5 Celsius). Image Credits: NASA/NRL.

Visible imagery and surface observations indicated that Marco made landfall around 7 p.m. EDT on Aug. 24 near the mouth of the Mississippi River. The center continued to move west and moved offshore and south of Louisiana by Aug. 25.

NASA’s Terra Satellite Reveals Effects of Wind Shear

NASA’s Terra satellite uses infrared light to analyze the strength of storms by providing temperature information about the system’s clouds. The strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.

On Aug. 25 at 12:30 a.m. EDT (0430 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Terra satellite observed Marco in infrared light and found a small area of storms where cloud top temperatures as cold as minus 50 degrees Fahrenheit (minus 45.5 Celsius) over the western Florida Panhandle and coastal Alabama. Those storms were being pushed northeast of Marco’s center from southwesterly wind shear. Satellite imagery also shows the low-level circulation center was a swirl of clouds south of Louisiana, over the Gulf of Mexico.

NASA’s EOS Terra satellite. Image Credit: NASA

In the Aug. 25, Marco discussion at 5 a.m. EDT, NHC Senior Hurricane Specialist Stacy Stewart noted, “Marco has been devoid of any significant convection for at least 12 hours.  [NOAA’s Advanced Scatterometer] ASCAT scatterometer surface wind data around 0239Z (10:39 p.m. EDT on Aug. 24) suggested that Marco might have degenerated in a north-to-south elongated trough (elongated area of low pressure). Based on this information, Marco has been downgraded to post-tropical remnant low [pressure area].”

About Wind Shear 

The shape of a tropical cyclone provides forecasters with an idea of its organization and strength. When outside winds batter a storm, it can change the storm’s shape and push much of the associated clouds and rain to one side of it. That is what wind shear does.

In general, wind shear is a measure of how the speed and direction of winds change with altitude. Tropical cyclones are like rotating cylinders of winds. Each level needs to be stacked on top each other vertically in order for the storm to maintain strength or intensify. Wind shear occurs when winds at different levels of the atmosphere push against the rotating cylinder of winds, weakening the rotation by pushing it apart at different levels.

Marco’s Final Status

At 5 a.m. EDT (0900 UTC) on Aug. 25, NOAA’s National Hurricane Center (NHC) reported the center of Post-Tropical Cyclone Marco was located near latitude 28.8 degrees north and longitude 91.2 degrees west. That is about 60 miles (100 km) south of Morgan City, La. and 110 miles (175 km) south-southeast of Lafayette, La. The post-tropical cyclone was moving toward the west near 10 mph (17 kph), and this general motion is expected to continue for the next day or so. Maximum sustained winds were near 30 mph (45 kph) with higher gusts. The estimated minimum central pressure was 1008.

Marco Nears its End

Brisk southwesterly vertical wind shear of 30 knots is forecast to increase to near 35 knots in 24 hours, which should prevent the redevelopment of deep convection near the center. On the forecast track, Marco should continue moving westward just offshore the coast of Louisiana until the system dissipates.

NASA Researches Tropical Cyclones

Hurricanes/tropical cyclones are the most powerful weather events on Earth. NASA’s expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America’s leadership in space and scientific exploration.

Related article:

Hurricanes Laura & Marco – Atlantic Ocean
https://orbiterchspacenews.blogspot.com/2020/08/hurricanes-laura-marco-atlantic-ocean.html

Related links:

NASA-NOAA’s Suomi NPP satellite: http://www.nasa.gov/mission_pages/NPP/main/index.html

For updated forecasts. visit: http://www.nhc.noaa.gov/

Text, Credits: NASA/Lynn Jenner/Goddard Space Flight Center, by Rob Gutro.

Greetings, Orbiter.ch

Station Crew Re-Enters U.S On-Orbit Segments, Mission Control Preps for Storm

ISS - Expedition 63 Mission patch.

August 25, 2020

The Expedition 63 crew ended its stay isolated in the Russian segment of the International Space Station this morning after an extended leak test. Mission Control also deployed remote teams to maintain 24/7 support for the station and its crew as Hurricane Laura approaches the Texas Gulf Coast.

Commander Chris Cassidy started the day reopening the hatches to the U.S. segment to begin resuming normal station operations. He reactivated U.S. life support equipment and restowed U.S. gear used during the crew’s weekend stay in the Zvezda service module.

Image above: The International Space Station was pictured by an Expedition 56 crew member aboard a departing Soyuz crew ship on Oct. 4, 2018. Image Credit: NASA.

Mission control will study the test data this week in an effort to determine the source of a cabin air leak detected in September of 2019. The rate is still well within segment specifications and presents no danger to the crew or the space station. The station’s atmosphere is maintained at a pressure comfortable for the crew members, and a tiny bit of that air leaks over time, requiring routine repressurization from nitrogen tanks delivered on cargo resupply missions.

Roscosmos Flight Engineer Anatoly Ivanishin spent the morning reconfiguring the Russian segment of the orbiting lab. The veteran station cosmonaut checked pressure valves and communications gear while opening hatches to various Russian modules.

Flight Engineer Ivan Vagner, on his first station mission, started the day resetting Russian life support equipment and sampling the air in Zvezda for analysis. Vagner also had time for science during the afternoon studying the Earth’s nighttime atmosphere and exploring ways to improve locating landmarks on Earth for photography.

International Space Station (ISS). Animation Credit: NASA

Meanwhile, personnel at NASA’s Johnson Space Center in Houston are monitoring Hurricane Laura and making general preparations at the center. A small team of flight controllers germane to monitoring and sending commands for the most important station systems were sent to a backup control center hub in central Texas in advance of the storm.

A full team of station flight controllers is getting set up at the Marshall Space Flight Center in Huntsville, Alabama, to take over longer-term control of station systems should that become necessary. This backup activity is planned for each hurricane season or for some other extenuating circumstance and will be executed with no impact on critical station operations or the safety of the crew.

Related articles:

Crew Spending Another Day in Russian Segment
https://orbiterchspacenews.blogspot.com/2020/08/crew-spending-another-day-in-russian.html

Crew Spending Weekend in Station’s Russian Segment
https://orbiterchspacenews.blogspot.com/2020/08/crew-spending-weekend-in-stations.html

Related links:

Expedition 63: https://www.nasa.gov/mission_pages/station/expeditions/expedition63/index.html

Zvezda service module: https://www.nasa.gov/mission_pages/station/structure/elements/zvezda-service-module.html

Locating landmarks on Earth: https://www.energia.ru/en/iss/researches/develop/04.html

Johnson Space Center (JSC): http://www.nasa.gov/centers/johnson/home/index.html

Marshall Space Flight Center: http://www.nasa.gov/centers/marshall/home/index.html

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/overview.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.

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