Month: December 2018

Delays in commercial crew program problematic for ISS

Government report advises NASA to develop contingency plans in the event deadlines aren’t met.

Both Boeing and SpaceX, companies with which NASA contracted to transport astronauts and supplies to the International Space Station (ISS) in 2019, could face delays of a year or more in obtaining agency certification for their vehicles, causing a gap in space station supply missions and astronaut transport.

Current schedules specify both companies will conduct un-crewed test flights in August of this year and crewed test flights shortly after, with Boeing’s scheduled for November and SpaceX’s for December.

Meeting these deadlines would enable both companies to be certified to fly astronauts to the ISS in early 2019–Boeing in January and SpaceX in February.

However, a report issued July 11 by the Government Accountability Office (GAO) expresses concern that both companies could miss the deadline for certification by at least a year. NASA’s contract with Russia for transportation of astronauts to and from the ISS via Soyuz capsules expires at the end of 2019, potentially leaving a gap with no supply missions or means of ferrying astronauts.

“Boeing and SpaceX continue to make progress developing a capability to fly to the ISS, but both have continued to experience delays. Additional delays could also disrupt US access to the ISS,” the report states.

NASA’s latest risk analysis predicts Boeing will be certified in December 2019 and SpaceX in January 2020. But these dates are estimates, and further delays could postpone both companies’ certifications to the fall of 2020.

Emphasizing the potential gap in access to the ISS, the GAO report advises NASA to develop a contingency plan for ISS access should the current deadlines not be met.

“If NASA does not develop options for ensuring access to the ISS in the event of further commercial crew delays, it will not be able to ensure that the US policy goal and objective for the ISS will be met,” the report notes.

NASA is already considering several options for dealing with the possible delays. One is extending Soyuz transport of astronauts until the end of 2020. Another is extending the crewed demonstration flights and prolonging astronauts’ stay on the space station by several months.

According to the GAO report, NASA has continued to insist the initial deadlines will be met by both Boeing and SpaceX even though the companies admit delays are likely.

NASA agreed to recommendations made in the report, including developing a contingency plan for ISS access by the end of this year, documenting its risk tolerance level for crew safety, and separating the job of managing commercial crew safety from that of independent safety oversight.

Atmosphere of hot exoplanet is boiling away

Parent star’s gravitational pull is siphoning planet’s atmospheric hydrogen.

The atmosphere of the hottest known exoplanet is boiling away, and its escaping gases are being captured by its parent star, according to a new study published in the journal Nature Astronomy.

A hot Jupiter, or gas giant planet orbiting very close to its star, KELT-9b was discovered last year by a team of scientists using the Kilodegree Extremely Little Telescope (KELT) at Winer Observatory in southeastern Arizona.

KELT uses the transit method to search for exoplanets, looking for periodic drops in a star’s brightness caused by a planet transiting or passing in front of its parent star.

The extremely hot star, KELT-9, is both hotter and larger than the Sun, with temperatures of 17,540 degrees Fahrenheit (9,726 degrees Celsius). Because the planet is in such a close orbit, circling KELT-9 once every 1.5 days, it is tidally locked to the star, with one hemisphere always facing the star and the other always facing away from it.

Temperatures on KELT-9b’s dayside are hotter than those of most stars and can reach 7,800 degrees Fahrenheit (4,300 degrees Celsius).  The planet is about twice the diameter of Jupiter and has nearly three times its mass.

In spite of being in such a close orbit, KELT-9b will not fall into its star, as some hot Jupiters do.

“This planet reminds me of the mythical Icarus, who came close to the Sun and crashed. Our planet will not crash, but it certainly will lose an essential part of itself, namely its atmosphere,” said Thomas Henning of the Max Planck Institute for Astronomy in a public statement.

When the researchers viewed the planet with the CARMENES instrument on the 3.5-meter telescope at Calar Alto Observatory in Spain, they found it to have an extended hydrogen atmosphere, a discovery that indicated the star’s gravity is not just heating the planet’s atmosphere, but sucking in its hydrogen.

“The large size (of the atmosphere) suggests the planet is losing hydrogen gas at a significant rate of more than 100,000 tons of hydrogen per second. The star is ‘boiling off’ the planet’s atmosphere, and pulling the gas onto itself, in a blatant case of interplanetary theft,” the researchers note in their statement.

The moon may have once supported life, study reports

New evidence suggests that the moon once had the right climate and atmosphere to support small microorganisms.

Scientists from the University of London and Washington State University have found evidence that the moon could have once had the conditions needed to support life, a new study published in Astrobiology reports.

Previously, astronomers believed that Earth’s natural satellite never had the volcanoes necessary to create an atmosphere.

However, the recent findings reveal that the lunar surface may have once had the conditions to support simple life forms around roughly 4 billion years ago.  

During that time, the moon spewed out superheated gas, including water vapor, from its core. That then created an atmosphere where the escaping steam may have turned into liquid pools on the surface.

If that happened, such areas could have been the perfect place for microorganisms to flourish. 

That is significant because if scientists can drill down into the moon and find signs of such life it will give them a glimpse of what used to exist on early Earth.

“It looks very much like the Moon was habitable at this time,” explained lead author Dirk Schulze-Makuch, an astrobiologist at Washington State University, according to Telegraph UK. “There could have actually been microbes thriving in water pools on the Moon until the surface became dry and dead. If liquid water and a significant atmosphere were present on the early Moon for long periods of time, we think the lunar surface would have been at least transiently habitable.”

The findings come from combination of recent space mission data and an analysis on lunar soil samples that show the moon is not as dry as previously believed.

In fact, in 2009 and 2010 a team of astronomers discovered that the celestial body holds hundreds of millions of metric tons of water ice. There could be water in the lunar mantle as well.

Such findings support the idea that the rocky satellite once held life. While today’s moon is sterile, four billions of years ago it would have been much more active.

“It seems bizarre to think about, but there may even have been liquid water on the Moon,” added study co-author Ian Crawford, a researcher at the University of London.

New map tracks radiation levels on Europa

Map will direct future Europa missions to locations that are potentially most habitable.

A new map that tracks radiation bombarding Jupiter’s moon Europa by its parent planet will prove an important tool in future missions searching for evidence of microbial life on the large moon.

After NASA’s Galileo mission revealed the likelihood of a global ocean beneath Europa’s surface, scientists have considered the Galilean moon a top contender for hosting microbial life.

Possible missions to Europa in various stage of planning seek to find biosignatures or signs of life in the underground ocean.

However, while Europa appears to be one of the solar system’s best hopes for finding life, the moon is regularly bombarded by powerful radiation from Jupiter, which could reduce habitability by breaking down or destroying material transported from the ocean to the surface.

Now, a new study led by Tom Nordheim of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, has produced the most comprehensive map ever of radiation levels on Europa using data returned by the Galileo mission’s flybys of Europa 20 years ago and electron measurements returned by Voyager 1, which flew by the Jupiter system in early 1979.

From the data returned by these missions, Nordheim’s team found radiation levels on Europa to vary significantly depending on location, with the highest radiation levels found near the equator and the lowest levels found near the poles.

The researchers produced a map that depicts high radiation zones as ovals.

“This is our first prediction of radiation levels at each point on Europa’s surface and is important information for future Europa missions,” noted Chris Paranicas of the Johns Hopkins Applied Physics Laboratory (JHUAPL) in Laurel, Maryland, who took part in the study.

“If we want to understand what’s going on at the surface of Europa and how that links to the ocean underneath, we need to understand the radiation,” Nordheim emphasized. “When we examine materials that have come up from the subsurface, what are we looking at? Does this tell us what is in the ocean, or is this what happened to the materials after they have been radiated?”

Nordheim’s research team also measured how deeply radiation from Jupiter penetrates beneath Europa’s surface, providing important information for the Europa Clipper mission, which will conduct about 45 Europa flybys while orbiting Jupiter following an early 2020s launch.

They found that in the regions with the highest radiation levels, a probe would have to drill four to eight inches (10 to 20 cm) to find preserved biosignatures. In those with the lowest radiation levels, the probe would have to drill less than 0.4 inches (one cm).

A paper on the study has been published in the journal Nature Astronomy.

NASA releases new mosaics of Saturn moon Titan

Infrared instrument successfully peered through atmospheric haze to reveal surface features.

Using six separate images of Saturn’s largest moon Titan collected by the Cassini orbiter over 13 years, NASA released new mosaics  showing the moon in stunning detail.

The images were collected by Cassini’s Visual and Infrared Mapping Spectrometer (VIMS) instrument, which observed in infrared wavelengths, enabling it to penetrate Titan’s hazy atmosphere, a feat not possible in visible wavelengths.

While this is not the first time VIMS images were used to create mosaics, it is the first time mission scientists produced mosaics that do not show the prominent seams that result from putting together images taken at different times, with a variety of lighting conditions and from a variety of angles.

By reanalyzing the VIMS data and processing the mosaics by hand, mission scientists successfully created the first seamless images of Saturn’s large 3,200-mile- (5,150-km-) wide moon, sometimes viewed as an analogue of early Earth.

Clearly visible in the colorful mosaics are Titan’s complex, varied surfaces, including seas of liquid hydrocarbons, icy deposits, and dunes that contain organic compounds.

“With the seams now gone, this new collection of images is by far the best representation of how the globe of Titan might appear to the casual observer if it weren’t for the moon’s hazy atmosphere,” mission scientists noted in a public statement.

Titan’s thick atmosphere, which contains a high percentage of nitrogen, conceals these diverse terrains. Small particles known as aerosols in the moon’s upper atmosphere scatter visible light, allowing viewers to see only a hazy orange sphere.

Atmospheric scattering and light absorption are much weaker in infrared wavelengths, which is why VIMS was able to obtain detailed photos of Titan’s surface.

Other than Earth, Titan is the only solar system object known to host liquids on its surface.

VIMS’s unique images of Titan will serve as a starting point for future missions observing the moon in the infrared in higher resolutions.

A proposed return to Titan, dubbed the Dragonfly mission, is one of two finalists in NASA’s New Frontiers program. To determine Titan’s habitability for life as we know it, Dragonfly would study the moon’s surface via a robotic minihelicopter.

If selected, Dragonfly will launch in 2025.

Cassini scientists also released a map of Titan showing latitudes, longitudes, and labeled surface features.

Bright quasar dates back to early universe

Discovery could help scientists better understand how the universe’s first galaxies formed.

The brightest quasar or active galactic nucleus ever detected dates back nearly 13 billion years, meaning it originated in the early universe and could potentially aid scientists in understanding the formation process of the first galaxies.

Quasars are extremely luminous super-massive black holes at the centers of galaxies. These black holes are active, meaning they are devouring large amounts of matter that form an accretion disk spiraling toward their centers. The most luminous, powerful, and remote energy sources in existence, quasars emit as much as one thousand times the energy output of the Milky Way galaxy across the entire electromagnetic spectrum.

A research team led by Eduardo Banadas of the Carnegie Institution for Science discovered the quasar PSO J1352.4034-15.3373 emitting the brightest radio emission ever detected as a result of high-speed jets shooting out of it towards Earth.

His discovery was confirmed by Emmanuel Momjian of the National Radio Astronomy Observatory, who, along with his science team, was able to view the jet emitted by the quasar with an unprecedented level of detail.

The researchers found the jets have been traveling for 13 billion years, making this quasar the first known to have been spewing jets within the first billion years of the universe’s 13.8-billion-year existence.

Unlike most quasars, this one does more than suck matter into its black hole. It also emits jets of plasma that travel at almost the speed of light. This makes the jets appear extremely bright when viewed with radio telescopes.

Approximately 10 percent of quasars are known to emit strong radio jets.

“There is a dearth of known strong radio emitters from the universe’s youth, and this is the brightest radio quasar at that epoch by any order of magnitude,” Banados stated.

Following the Big Bang, the universe was dark as it expanded and cooled into neutral hydrogen gas, with few sources of brightness. Approximately 800 million years after the Big Bang, gravity condensed matter into the first galaxies and stars, which released energy, causing the neutral hydrogen to lose an electronic and become ionized, generating light.

“The jet from this quasar could serve as an important calibration tool to help future projects penetrate the dark ages and perhaps reveal how the earliest galaxies came into being,” Banados emphasized.

Findings of the study have been published in two separate papers in The Astrophysical Journal.

Astronomers capture ghostly particle in Antarctic ice sheet

The new discovery could usher in a new era of neutrino astronomy.

A ghostly particle was captured in a patch of ice beneath the South Pole in September of last year by the IceCube Antarctic detector—the orbiting Fermi Gammaray Space Telescope. Astronomers believe that this particle—a neutrino, electrically neutral and almost massless—likely came for a far off blazar, a hugely bright source of radiation powered by a supermassive black hole. The new finding could mark the founding event of neutrino astronomy, writes Daniel Clery in Science.

These particles are known as ultrahigh-energy cosmic rays because they exude a million times more energy than those produced in earthbound particle accelerators. Astronomers have yet to unequivocally pinpoint the source that boosts these particles to massive energies, but have speculated that it could be neutron stars, gamma ray bursts, hypernovae, or radiation-spewing black holes. However, they believe that whatever the source, high energy neutrinos are a likely byproduct. The IceCube neutrino detector captures these elusive particles in a cubic kilometer of Antarctic ice. Based on the location, timing, and brightness of the detected light, researchers can reconstruct the path and energy of the neutrino.

Last September’s ensnared neutrino, called IceCube-170922A, is calculated to have an energy of 290 TeV, and has offered scientists a clear track back into space. Six days after the observation, the Fermi team reported the satellite discovered a blazar, called TXS 0506+056, was especially bright, having started to flare, and less than 0.1° away from the neutrino’s path. Blazars are distant cosmic beacons powered by supermassive black holes that fire jets of particles from their poles. Though it’s not clear whether TXS 0506+056 was flaring when IceCube-170922A started its journey to Earth, Pierre Sokolsky of the University of Utah in Salt Lake City has hope, saying “it’s a very mouthwatering observation and I very much hope it will be confirmed.”

New ‘ghost dunes’ uncovered on Mars

Astronomers have found hundreds of never before seen ghost dunes on the Martian surface.

Researchers from the University of Washington have discovered hundreds imprints of ancient sand piles — known as ghost dunes — on Mars’ surface, according to a recent study in the Journal of Geophysical Research.

The team found the remains in two different locations on the Red Planet, a discovery that could give insight into the world’s past climate.

The dunes formed back when the planet had both flowing water and active volcanoes. Such natural processes covered the formations with sediment about two billion years ago and slowly hardened them over time. Then, harsh winds blew the sand away from the inside and left the imprints behind.

This is not the first time astronomers have discovered ghost dunes on Mars — there are some in the Medusa Fossae formation for instance — but the new research identified 300 previously undiscovered ones in both the Hellas Basin and the Noctis Labyrinthus.

They made the discovery by looking at images of the Mars’ surface and then scanning the pictures for clusters of crescent-shaped pits. That unique shape indicates the dunes were “barchan dunes,” which form on flat surfaces with unidirectional winds.

Studying the orientation allowed scientists to determine that the winds came from the north and steadily pushed the dunes south. That is strictly different than the wind direction today, suggesting that environmental conditions on the planet shifted over time.

“One of the cool things about the ghost dunes is that they tell us, for sure, that the wind on Mars was different in the ancient past, when they formed,” said lead author Mackenzie Day, a researcher at the University of Washington, in a statement. 

In addition, the team managed to figure out how big the dunes were. The ones in the Hellas Basin averaged 250 feet tall, while the ones in the Noctis Labyrinthus were roughly half that size.

The finding is interesting, and the researchers hope to follow up on their study could give new insight into the rocky landscape. There is also a chance that the wind did not fully clear the molds and that some ancient sand could still be stuck in them.

“There is probably nothing living there now,” added Day, according to Atlas Obscura. “But if there ever was anything on Mars, this is a better place on average to look.”