Sunday, July 30, 2017

MILKY WAY - As Much as Half of the Milky Way Likely Came From Distant Galaxies

As Much as Half of the Milky Way Likely Came From Distant Galaxies:

As Much as Half of the Milky Way Likely Came From Distant Galaxies
Credit: Kristin Samuelson/Northwestern University

We're made of star stuff, as Carl Sagan famously put it in his TV series Cosmos. All of the elements that joined together to form our planet and everything on it were set in motion within the hearts of ancient stars. But not only are we star stuff, it appears that we're actually made of alien star stuff.

Astrophysicists who were analyzing galaxy formation recently looked at how intergalactic gas and dust is transported over time and across great distances. They found that up to half of the matter in our Milky Way galaxy likely comes from other galaxies far, far away.

"Given how much of the matter out of which we formed may have come from other galaxies, we could consider ourselves space travelers or extragalactic immigrants," Daniel Anglés-Alcázar, an astrophysics postdoctoral fellow from Northwestern University who led the study, said in a statement. "It is likely that much of the Milky Way's matter was in other galaxies before it was kicked out by a powerful wind, traveled across intergalactic space and eventually found its new home in the Milky Way."

This is a "first-of-its-kind analysis," the team said, with the findings opening a new line of research into understanding galaxy formation. The study appears in the Monthly Notices of the Royal Astronomical Society.

Anglés-Alcázar and his fellow researchers used a supercomputer simulation based on the FIRE (Feedback in Realistic Environments) project, which is co-led by Northwestern physics and astronomy professor Claude-André Faucher-Giguère. FIRE uses numerical simulations that can produce realistic 3D models of galaxies. Anglés-Alcázar developed state-of-the-art algorithms to follow how a galaxy forms over time, from just after the Big Bang to the present day.

Using the equivalent of several million hours of continuous computing time, the team was able to quantify how galaxies acquire matter from the universe over time. They did this by "tracing cosmic inflows, galactic outflows, gas recycling, and merger histories," according to their paper.

The findings on galactic evolution were unexpected, and the researchers coined a new term to explain the phenomenon: intergalactic transfer.

RELATED: Cosmic Blast of X-rays Inexplicably Outshines All of a Galaxy's Stars

The simulations showed that supernova explosions within galaxies eject enormous amounts of gas, which causes atoms to be transported from one galaxy to another via powerful galactic winds. Even though galaxies are far apart from each other, the galactic winds propagate material at several hundred kilometers per second, and over several billion years this process infused new material into galaxies, sparking star formation.

"We show that in situ star formation fueled by fresh accretion dominates the early growth of galaxies of all masses, while the re-accretion of gas previously ejected in galactic winds often dominates the gas supply for a large portion of every galaxy's evolution," the team wrote. "Externally processed material contributes increasingly to the growth of central galaxies at lower redshifts."

By tracking in detail the complex flows of matter in the simulations, the research team found that gas flows from smaller galaxies to larger galaxies, such as the Milky Way, where the gas forms stars. Additionally, even stars formed in one galaxy could be transferred to another. This transfer of mass through galactic winds can account for up to 50 percent of matter in the larger galaxies, the researchers said.

"In our simulations, we were able to trace the origins of stars in Milky Way-like galaxies and determine if the star formed from matter endemic to the galaxy itself or if it formed instead from gas previously contained in another galaxy," said Anglés-Alcázar.

The accepted theory of galactic formation is that shortly after the Big Bang, the hydrogen, helium and other trace elements started to clump together due to small density fluctuations, perhaps from dark matter that that provided the initial gravitational attraction. Matter then bunched together into larger and larger collections, forming the first proto-galaxies.

RELATED: Young Galaxy's Old Stardust Sheds Light on the First Stars

Within these first galaxies, more clumps of material came together to eventually create the first stars. These stars lived short violent lives, ending in powerful supernovae that then seeded the next generations of stars. The first galaxies were gravitationally attracted to one other, and merged together into larger and larger structures, ultimately becoming the large spiral galaxies we know today.

But the intergalactic transfer of gas from other galaxies is "an important but previously under-appreciated growth mode," the researchers said, emphasizing that their study showed that galactic winds are a "primary contributor to the baryonic mass budget of central galaxies."

"This study transforms our understanding of how galaxies formed from the Big Bang," Faucher-Giguère remarked in a statement. "What this new mode implies is that up to one-half of the atoms around us — including in the solar system, on Earth and in each one of us — comes not from our own galaxy but from other galaxies, up to one million light-years away."

"Our origins are much less local than we previously thought," he added. "This study gives us a sense of how things around us are connected to distant objects in the sky."

Originally published on Seeker.

JUPITER - Wow! This Is What Jupiter's Great Red Spot Would Look Like to You

Wow! This Is What Jupiter's Great Red Spot Would Look Like to You:

Wow! This Is What Jupiter's Great Red Spot Would Look Like to You
This true-color image shows what Jupiter’s Great Red Spot would look like to a human observer from the position of NASA’s Juno Jupiter orbiter. Citizen scientist Björn Jónsson created the photo using data from Juno’s JunoCam imager.
Credit: NASA/JPL-Caltech/SwRI/MSSS/Björn Jónsson

If you'd been riding aboard NASA's Juno probe when it zoomed over Jupiter's famous Great Red Spot earlier this month, this is what you would have seen.

A newly released photo gives a dramatic look at that July 10 close pass, capturing Juno's view of the enormous storm from an altitude of just 8,648 miles (13,918 kilometers).

"This true-color image offers a natural-color rendition of what the Great Red Spot and surrounding areas would look like to human eyes from Juno's position," NASA officials wrote in an image description Thursday (July 27). "The tumultuous atmospheric zones in and around the Great Red Spot are clearly visible."

The image was created by citizen scientist Björn Jónsson using data collected by Juno's JunoCam imager. NASA encourages anyone who wishes to process JunoCam raw images to do so; go to for more information.

The $1.1 billion Juno mission launched in August 2011 and arrived in orbit around Jupiter on July 4, 2016. The probe is zooming around the huge planet on a highly elliptical path, making close approaches, or "perijoves," once every 53.5 days.

Juno is investigating Jupiter's composition and interior structure, with the aim of helping scientists better understand the gas giant's formation and evolution. The probe collects most of its data during perijove passes like the July 10 event, seven of which it has completed so far (not counting the initial one on July 4 of last year, when Juno's science gear was turned off).

Juno's mission is scheduled to last until at least February 2018.

The Great Red Spot has been raging for centuries. The huge storm is about 10,000 miles (16,000 km) wide, meaning it's bigger than the entire Earth. However, it used to be even bigger; the Great Red Spot has long been shrinking, for reasons that scientists don't entirely understand.

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+. Originally published on

BIG BANG ? Curious Kids: What Started the Big Bang?

Curious Kids: What Started the Big Bang?: expert-voices-banner.jpg?1363814412

Curious Kids: What Started the Big Bang?
In the beginning, the Universe expanded very, very fast.
Credit: Flickr/Jamie, CC BY-SA

This is an article from Curious Kids, a series for children. The Conversation is asking kids to send in questions they'd like an expert to answer. All questions are welcome – serious, weird or wacky! The article was originally published at The Conversation. The publication contributed the article to's Expert Voices: Op-Ed & Insights.

What started the Big Bang? – Pippi, 8, Canberra.
This is one of the two questions I get asked a lot (the other one is: do aliens exist?) Both are very good questions! Pippi, the short answer is that we do not know what started the Big Bang. This is a big mystery.

The Big Bang is an idea about the history of the Universe, the history of space and time and matter ("stuff") and energy. The Universe is about 13.8 billion years old and from observations we make using telescopes we can tell that the Universe was very small 13.8 billion years ago.

Observations also suggest that in the first fraction of a second, the Universe seemed to expand very quickly but then slow down. After a few hundred thousand years, the simplest type of atom formed: hydrogen. The hydrogen started to form stars and galaxies.

After billions of years the Earth (and us) formed from the atoms made inside stars - every atom in your body more complicated than hydrogen was made by a star at some point in the last 13.8 billion years. In all that time, the Universe has continued to expand. In fact, observations now tell us that the expansion of the Universe is getting faster.

The idea of the Big Bang agrees with all these observations. So scientists think the Big Bang is an idea that does a good job of describing the history of the Universe.

However, the idea is not perfect. We don't know why the Universe expanded so quickly in the first second and then slowed down. We don't know why the expansion of the Universe is speeding up now. We don't know why we have a certain number of forces that control the Universe. And we don't know what started the Big Bang!

Very large telescopes, like the Murchison Widefield Array can make observations that help us understand how the Universe evolved.

It took hundreds of years to build the idea of the Big Bang, and it may take a long time to improve it or find an idea that is better. Scientists have a lot of ideas about how the Big Bang started. But these ideas must agree with our observations of the Universe.

The future is very exciting for anyone who wants to help figure this out. The advanced technology we have means that we can build machines that smash particles (tiny little bits of stuff even smaller than an atom) together to show what happened right after the Big Bang. We can now build powerful new telescopes to observe the stars and galaxies in the Universe in a lot of detail. We will use these machines and telescopes to see which ideas about the Big Bang are right and which are wrong.

Sometimes new ideas take many years to be worked out. Sometimes new ideas pop into people's heads very quickly. It is very exciting to have a new idea about the Universe. We will need lots of people who are good at puzzles to help us.

Hello, curious kids! Have you got a question you'd like an expert to answer? Ask an adult to send your question to us. They can:

* Email your question to
* Tell us on Twitter by tagging @ConversationEDU with the hashtag #curiouskids, or
* Tell us on Facebook

Please tell us your name, age, and which city you live in. You can send an audio recording of your question too, if you want. Send as many questions as you like! We won't be able to answer every question but we will do our best.

Steven Tingay, Professor of Radio Astronomy, Curtin University

This article was originally published on The Conversation. Read the original article. Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook, Twitter and Google +. The views expressed are those of the author and do not necessarily reflect the views of the publisher. This version of the article was originally published on

MARS - Hubble Sees Tiny Phobos Orbiting Mars

Hubble Sees Tiny Phobos Orbiting Mars:

Mars’ moon Phobos is a pretty fascinating customer! Compared to Mars other moon Deimos, Phobos (named after the Greek personification of fear) is the larger and innermost satellite of the Red Planet. Due to its rapid orbital speed, the irregularly-shaped moon orbits Mars once every 7 hours, 39 minutes, and 12 seconds. In other words, it completes over three orbits of Mar within a single Earth day.

It’s not too surprising then that during a recent observation of Mars with the Hubble space telescope,  Phobos chose to photobomb the picture! It all took place in May of 2016, when while Mars was near opposition and Hubble was trained on the Red Planet to take advantage of it making its closest pass to Earth in over a decade. The well-timed sighting also led to the creation of a time-lapse video that shows the moon’s orbital path.

During an opposition, Mars and Earth are at the closest points in their respective orbits to each other. Because Mars and the Sun appear to be on directly opposite sides of Earth, the term “opposition” is used. These occur every 26 months, and once every 15 to 17 years, an opposition will coincide with Mars being at the closest point in its orbit to the Sun (perihelion).

Phobos from NASA’s Mars Reconnaissance Orbiter on March 23, 2008. Credit: NASA
When this happens, Mars is especially close to Earth, which makes it an ideal occasion to photograph it. The last time this occurred was on May 22nd, 2016, when Mars was and Earth were at a distance of about 76,309,874 km (47,416,757 mi or 0.5101 AU) from each other. This would place it closer to Earth than it had been in 11 years, and the Hubble space telescope was trained on Mars to take advantage of this.

A few days before Mars made its closest pass, Hubble took 13 separate exposures of the planet over the course of 22 minutes, allowing astronomers to create a time-lapse video. This worked out well, since Phobos came into view during the exposures, which led the video showing the path of the moon’s orbit. Because of its small size, Phobos looked like a star that was popping out from behind the planet.

This sighting has only served to enhance Phobos’ fascinating nature. As of 2017, astronomers have been aware of the moon’s existence for 140 years. It was discovered in 1877, when Asaph Hall – while searching for Martian moons – observed it from the U.S. Naval Observatory in Washington D.C. A few days later, he also discovered Deimos, the smaller, outer moon of Mars.

In July of 1969, just two weeks before the Apollo landing, the Mariner 7 probe conducted a flyby of Mars and took the first close-up images of the Moon. In 1977, a year after the Viking 1 lander was deployed to the Martian surface, NASA’s Viking 1 orbiter took the first detailed photographs of the moon. These revealed a cratered surface marred by long, shallow grooves and one massive crater – known as the Stickney crater.

The streaked and stained surface of Phobos, with a close-up on the Stickney crater. Credit: NASA
Asaph Hall named this crater after Chloe Angeline Stickney Hall (his wife) after discovering it in 1878, a year after he discovered Phobos and Deimos. Measuring some 10 km in diameter – almost half of the average diameter of Phobos itself – the impact that created Stickney is believed to have been so powerful that it nearly shattered the moon.

The most widely-accepted theory about Phobos origins is that both it and Deimos were once asteroids that were kicked out of the Main Belt by Jupiter’s gravity, and were then acquired by Mars. But unlike Deimos, Phobos’ orbit is unstable. Every century, the moon draws closer to Mars by about 1.98 meters (6.5 feet). At this rate, scientist estimate that within 30 to 50 million years, it will crash into Mars or be torn to pieces to form a ring in orbit.

This viewing is perhaps a reminder that this satellite won’t be with Mars forever. Then again, it will certainly still be there if and when astronauts (and maybe even colonists) begin setting foot on the planet. To these people, looking up at the sky from the surface of Mars, Phobos will be seen regularly eclipsing the Sun. Because of its small size, it does not fully eclipse the Sun, but it does make transits multiple times in a single day.

So there’s still plenty of time to study and enjoy this fearfully-named moon. And while you’re at it, be sure to check out the video below, courtesy of NASA’s Goddard Space Center!

Further Reading: HubbleSite, NASA

The post Hubble Sees Tiny Phobos Orbiting Mars appeared first on Universe Today.

Cassini Finds that Titan is Building the Chemicals that Might Have Led to Life on Earth

Cassini Finds that Titan is Building the Chemicals that Might Have Led to Life on Earth:

Titan, Saturn’s largest moon, has been a source of mystery ever since scientists began studying it over a century ago. These mysteries have only deepened with the arrival of the Cassini-Huygens mission in the system back in 2004. In addition to finding evidence of a methane cycle, prebiotic conditions and organic chemistry, the Cassini-Huygens mission has also discovered that Titan may have the ingredient that help give rise to life.

Such is the argument made in a recent study by an international team of scientists. After examining data obtained by the Cassini space probe, they identified a negatively charged species of molecule in Titan’s atmosphere. Known as “carbon chain anions”, these molecules are thought to be building blocks for more complex molecules, which could played a key role in the emergence of life of Earth.

The study, titled “Carbon Chain Anions and the Growth of Complex Organic Molecules in Titan’s Ionosphere“, recently appeared in The Astrophysical Journal Letters. The team included researchers from University College in London, the University of Grenoble, Uppsalla University, UCL/Birkbeck, the University of Colorado, the Swedish Institute of Space Physics, the Southwest Research Institute (SwRI), and NASA’s Goddard Space Flight Center.

Diagram of the internal structure of Titan according to the fully differentiated dense-ocean model. Credit: Wikipedia Commons/Kelvinsong
As they indicate in their study, these molecules were detected by the Cassini Plasma Spectrometer (CAPS) as the probe flew through Titan’s upper atmosphere at an distance of 950 – 1300 km (590  – 808 mi) from the surface. They also show how the presence of these molecules was rather unexpected, and represent a considerable challenge to current theories about how Titan’s atmosphere works.

For some time, scientists have understood that within Titan’s ionosphere, nitrogen, carbon and hydrogen are subjected to sunlight and energetic particles from Saturn’s magnetosphere. This exposure drives a process where these elements are transformed into more complex prebiotic compounds, which then drift down towards the lower atmosphere and form a thick haze of organic aerosols that are thought to eventually reach the surface.

This has been the subject of much interest, since the process through which simple molecules form complex organic ones has remained something of a mystery to scientists. This could be coming to an end thanks to the detection of carbon chain anions, though their discovery was altogether unexpected. Since these molecules are highly reactive, they are not expected to last long in Titan’s atmosphere before combining with other materials.

However, the data showed that the carbon chains became depleted closer to the moon, while precursors to larger aerosol molecules underwent rapid growth. This suggests that there is a close relationship between the two, with the chains ‘seeding’ the larger molecules. Already, scientists have held that these molecules were an important part of the process that allowed for life to form on Earth, billions of years ago.

A halo of light surrounds Saturn’s moon Titan in this backlit picture, showing its atmosphere. Credit: NASA/JPL/Space Science Institute
However, their discovery on Titan could be an indication of how life begins to emerge throughout the Universe. As Dr. Ravi Desai, University College London and the lead author of the study, explained in an ESA press release:

“We have made the first unambiguous identification of carbon chain anions in a planet-like atmosphere, which we believe are a vital stepping-stone in the production line of growing bigger, and more complex organic molecules, such as the moon’s large haze particles. This is a known process in the interstellar medium, but now we’ve seen it in a completely different environment, meaning it could represent a universal process for producing complex organic molecules.”
Because of its dense nitrogen and methane atmosphere and the presence of some of the most complex chemistry in the Solar System, Titan is thought by many to be similar to Earth’s early atmosphere. Billions of years ago, before the emergence of microorganisms that allowed for subsequent build-up of oxygen, it is likely that Earth had a thick atmosphere composed of nitrogen, carbon dioxide and inert gases.

Therefore, Titan is often viewed as a sort planetary laboratory, where the chemical reactions that may have led to life on Earth could be studied. However, the prospect of finding a universal pathway towards the ingredients for life has implications that go far beyond Earth. In fact, astronomers could start looking for these same molecules on exoplanets, in an attempt to determine which could give rise to life.

This illustration shows Cassini above Saturn’s northern hemisphere prior to one of its 22 Grand Finale dives. Credit: NASA/JPL-Caltech
Closer to home, the findings could also be significant in the search for life in our own Solar System. “The question is, could it also be happening within other nitrogen-methane atmospheres like at Pluto or Triton, or at exoplanets with similar properties?” asked Desia. And Nicolas Altobelli, the Project Scientist for the Cassini-Huygens mission, added:

These inspiring results from Cassini show the importance of tracing the journey from small to large chemical species in order to understand how complex organic molecules are produced in an early Earth-like atmosphere. While we haven’t detected life itself, finding complex organics not just at Titan, but also in comets and throughout the interstellar medium, we are certainly coming close to finding its precursors.
Cassini’s “Grande Finale“, the culmination of its 13-year mission around Saturn and its system of moons, is set to end on September 15th, 2017. In fact, as of the penning of this article, the mission will end in about 1 month, 18 days, 16 hours, and 10 minutes. After making its final pass between Saturn’s rings, the probe will be de-orbited into Saturn’s atmosphere to prevent contamination of the system’s moons.

However, future missions like the James Webb Space Telescope, the ESA’s PLATO mission and ground-based telescopes like ALMA are expected to make some significant exoplanet finds in the coming years. Knowing specifically what kinds of molecules are intrinsic in converting common elements into organic molecules will certainly help narrow down the search for habitable (or even inhabited) planets!

Further Reading: ESA, The Astrophysical Journal Letters

The post Cassini Finds that Titan is Building the Chemicals that Might Have Led to Life on Earth appeared first on Universe Today.

MILKY WAY ? What Is the Name Of Our Galaxy?

What Is the Name Of Our Galaxy?:

Since prehistoric times, human beings have looked up at at the night sky and pondered the mystery of the band of light that stretches across the heavens. And while theories have been advanced since the days of Ancient Greece as to what it could be, it was only with the birth of modern astronomy that scholars have come come to know precisely what it is – i.e. countless stars at considerable distances from Earth.

The term “Milky Way”, a term which emerged in Classical Antiquity to describe the band of light in the night sky, has since gone on to become the name for our galaxy. Like many others in the known Universe, the Milky Way is a barred, spiral galaxy that is part of the Local Group – a collection of 54 galaxies. Measuring 100,000 – 180,000 light-years in diameter, the Milky Way consists of between 100 and 400 billion stars.


The Milky Way consists of a Galactic Center that is shaped like a bar and a Galactic Disk made up of spiral arms, all of which is surrounded by the Halo – which is made up of old stars and globular clusters. The Center, also known as “the bulge”,  is a dense concentration of mostly old stars that measures about 10,000 light years in radius. This region is also the rotational center of the Milky Way.

Illustration of the supermassive black hole at the center of the Milky Way. Credit: NRAO/AUI/NSF

Illustration of the supermassive black hole at the center of the Milky Way. Credit: NRAO/AUI/NSF
The Galactic Center is also home to an intense radio source named Sagittarius A*, which is believed to have a supermassive black hole (SMBH) at its center. The presence of this black hole has been discerned due to the apparent gravitational influence it has on surrounding stars. Astronomers estimate that it has a mass of between 4.1. and 4.5 million Solar masses.

Outside the barred bulge at the Galactic Center is the Galactic Disk of the Milky Way. This consists of stars, gas and dust which is organized into four spiral arms. These arms typically contain a higher density of interstellar gas and dust than the Galactic average, as well as a greater concentration of star formation. While there is no consensus on the exact structure or extent of these spiral arms, they are commonly grouped into two or four different arms.

In the case of four arms, this is based on the traced paths of gas and younger stars in our galaxy, which corresponds to the Perseus Arm, the Norma and Outer Arm, the Scutum-Centaurum Arm, and the Carina-Sagittarius Arm. There are also at least two smaller arms, which include the Cygnus Arm and the Orion Arm. Meanwhile, surveys based on the presence of older stars show only two major spirals arms – the Perseus arm and the Scutum–Centaurus arm.

Beyond the Galactic Disk is the Halo, which is made up of old stars and globular clusters – 90% of which lie within 100,000 light-years (30,000 parsecs) from the Galactic Center. Recent evidence provided by X-ray observatories indicates that in addition to this stellar halo, the Milky way also has a halo of hot gas that extends for hundreds of thousands of light years.

Artist’s conception of the spiral structure of the Milky Way with two major stellar arms and a bar. Credit: NASA/JPL-Caltech/ESO/R. Hurt

Size and Mass:

The Galactic Disk of the Milky Way Galaxy is approximately 100,000 light years in diameter and about 1,000 light years thick. It is estimated to contain between 100 and 400 billion stars, though the exact figure depends on the number of very low-mass M-type (aka. red dwarf) stars. This is difficult to determine because these stars also have low-luminosity compared to other class.

The distance from the Sun to the Galactic Center is estimated to be between 25,000 to 28,000 light years (7,600 to 8,700 parsecs). The Galactic Center’s bar (aka. its “bulge”)  is thought to be about 27,000 light-years in length and is composed primarily of red stars, all of which are thought to be ancient. The bar is surrounded by the ‘5-kpc ring’, a region that contains much of the galaxy’s molecular hydrogen and where star-formation is most intense.

The Galactic Disk has a diameter of between 70,000 and 100,000 light-years. It does not have a sharp edge, a radius beyond which there are no stars. However, the number of stars drops slowly with distance from the center. Beyond a radius of roughly 40,000 light years, the number of stars drops much faster the farther you get from the center.

Location of the Solar System:

The Solar System is located near the inner rim of the Orion Arm, a minor spiral arm located between the Carina–Sagittarius Arm and the Perseus Arm. This arm measures some 3,500 light-years (1,100 parsecs) across,  approximately 10,000 light-years (3,100 parsecs) in length, and is at a distance of about 25,400 to 27,400 light years (7.78 to 8.4 thousand parsecs) from the Galactic Center.

History of Observation:

Our galaxy was named because of the way the haze it casts in the night sky resembled spilled milk. This name is also quite ancient. It is translation from the Latin “Via Lactea“, which in turn was translated from the Greek for Galaxias, referring to the pale band of light formed by stars in the galactic plane as seen from Earth.

Persian astronomer Nasir al-Din al-Tusi (1201–1274) even spelled it out in his book Tadhkira: “The Milky Way, i.e. the Galaxy, is made up of a very large number of small, tightly clustered stars, which, on account of their concentration and smallness, seem to be cloudy patches. Because of this, it was likened to milk in color.”

Astronomers had long suspected the Milky Way was made up of stars, but it wasn’t proven until 1610, when Galileo Galilei turned his rudimentary telescope towards the heavens and resolved individual stars in the band across the sky. With the help of telescopes, astronomers realized that there were many, many more stars in the sky, and that all of the ones that we can see are a part of the Milky Way.

In 1755, Immanuel Kant proposed that the Milky Way was a large collection of stars held together by mutual gravity. Just like the Solar System, this collection would be rotating and flattened out as a disk, with the Solar System embedded within it. Astronomer William Herschel (discoverer of Uranus) tried to map its shape in 1785, but he didn’t realize that large portions of the galaxy are obscured by gas and dust, which hide its true shape.

It wasn’t until the 1920s, when Edwin Hubble provided conclusive evidence that the spiral nebulae in the sky were actually whole other galaxies, that the true shape of our galaxy was known. Thenceforth, astronomers came to understand that the Milky Way is a barred, spiral galaxy, and also came to appreciate how big the Universe truly is.

The Milky Way is appropriately named, being the vast and cloudy mass of stars, dust and gas it is. Like all galaxies, ours is believed to have formed from many smaller galaxies colliding and combining in the past. And in 3 to 4 billion years, it will collide with the Andromeda Galaxy to form an even larger mass of stars, gas and dust. Assuming humanity still exists by then (and survives the process) it should make for some interesting viewing!

We have written many interesting articles about the Milky Way here at Universe Today. Here’s 10 Interesting Facts About the Milky Way, How Big is the Milky Way?, Why is our Galaxy Called the Milky Way?, What is the Closest Galaxy to the Milky Way?, Where is the Earth in the Milky Way?, The Milky Way has Only Two Spiral Arms, and It’s Inevitable: Milky Way, Andromeda Galaxy Heading for Collision.

If you’d like more info on galaxies, check out Hubblesite’s News Releases on Galaxies, and here’s NASA’s Science Page on Galaxies.

We’ve also recorded an episode of Astronomy Cast about the Milky Way. Listen here, Episode 99: The Milky Way.


The post What Is the Name Of Our Galaxy? appeared first on Universe Today.

MILKY WAY - The Milky Way over Monument Valley

The Milky Way over Monument Valley:

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2017 July 26

See Explanation. Moving the cursor over the image will bring up an annotated version. Clicking on the image will bring up the highest resolution version available.
Explanation: You don't have to be at Monument Valley to see the Milky Way arc across the sky like this -- but it helps. Only at Monument Valley USA would you see a picturesque foreground that includes these iconic rock peaks called buttes. Buttes are composed of hard rock left behind after water has eroded away the surrounding soft rock. In the featured image taken a month ago, the closest butte on the left and the butte to its right are known as the Mittens, while Merrick Butte can be seen farther to the right. Green airglow fans up from the horizon. High overhead stretches a band of diffuse light that is the central disk of our spiral Milky Way Galaxy. The band of the Milky Way can be spotted by almost anyone on almost any clear night when far enough from a city and surrounding bright lights, but a sensitive digital camera is needed to capture these colors in a dark night sky.

CONSTELLATION A Sagittarius Triplet

A Sagittarius Triplet:

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2017 July 27

See Explanation. Clicking on the picture will download the highest resolution version available.
Explanation: These three bright nebulae are often featured on telescopic tours of the constellation Sagittarius and the crowded starfields of the central Milky Way. In fact, 18th century cosmic tourist Charles Messier cataloged two of them; M8, the large nebula above and left of center, and colorful M20 near the bottom of the frame. The third emission region includes NGC 6559, right of M8 and separated from the larger nebula by a dark dust lane. All three are stellar nurseries about five thousand light-years or so distant. Over a hundred light-years across the expansive M8 is also known as the Lagoon Nebula. M20's popular moniker is the Trifid. Glowing hydrogen gas creates the dominant red color of the emission nebulae. In striking contrast, blue hues in the Trifid are due to dust reflected starlight. The colorful composite skyscape was recorded with two different telescopes to capture a widefield image of the area and individual close-ups at higher resolution.

PHOTOGRAPH - Aurora Slathers up the Sky

Aurora Slathers up the Sky:

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2017 July 29

See Explanation. Clicking on the picture will download the highest resolution version available.

Aurora Slathers up the Sky

Image Credit: Jack Fischer, Expedition 52, NASA

Explanation: Like salsa verde on your favorite burrito, a green aurora slathers up the sky in this June 25 snapshot from the International Space Station. About 400 kilometers (250 miles) above Earth, the orbiting station is itself within the upper realm of the auroral displays. Aurorae have the signature colors of excited molecules and atoms at the low densities found at extreme altitudes. Emission from atomic oxygen dominates this view. The tantalizing glow is green at lower altitudes, but rarer reddish bands extend above the space station's horizon. The orbital scene was captured while passing over a point south and east of Australia, with stars above the horizon at the right belonging to the constellation Canis Major, Orion's big dog. Sirius, alpha star of Canis Major, is the brightest star near the Earth's limb.

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Wednesday, July 26, 2017

MOON LANDER - Astrobotic's Private Moon Lander Will Launch in 2019 on Atlas V Rocket

Astrobotic's Private Moon Lander Will Launch in 2019 on Atlas V Rocket:

Astrobotic's Private Moon Lander Will Launch in 2019
Artist's illustration of Astrobotic's Peregrine lunar lander on the surface of the moon.
Credit: Astrobotic

A private moon lander now has a ride to space for its maiden lunar mission in 2019.

Pittsburgh-based Astrobotic's robotic Peregrine lander will lift off atop a United Launch Alliance (ULA) Atlas V rocket on its first trip to the moon's surface two years from now, representatives of both companies announced today (July 26).

"Astrobotic is thrilled to select a ULA launch vehicle as the means to get Peregrine to the moon," Astrobotic CEO John Thornton said in a statement. "By launching with ULA, Astrobotic can rest assured our payload customers will ride on a proven launch vehicle with a solid track record of success."

During the 2019 mission, Peregrine will carry 77 lbs. (35 kilograms) of payload to the lunar surface. Astrobotic has already signed 11 contracts with customers who want to participate in this flight, company representatives said.

This first mission is a demonstration designed to prove out Peregrine's capabilities. Astrobotic envisions the lander eventually entering relatively frequent service, ferrying up to 585 lbs. (265 kg) at a time to the moon for a variety of customers, from government space agencies such as NASA to companies that aim to exploit lunar resources, Astrobotic representatives said.

Peregrine may not be the first private lander to touch down on the moon, however, even if Astrobotic's 2019 schedule holds. Five teams remain in the Google Lunar X Prize (GLXP), which will award $20 million to the first privately funded group to land a robotic spacecraft on the moon, move it at least 1,640 feet (500 meters) and have it beam home high-resolution photos and imagery.

These five teams — Hakuto, Moon Express, SpaceIL, Synergy Moon and TeamIndus — have until the end of the year to accomplish these goals; the prize expires after Dec. 31, 2017.

Astrobotic was a participant in the GLXP, but the company dropped out last year.

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+. Originally published on

BLACK HOLES - Boom! Powerful Cosmic Explosion May Hint at How Black Holes Form

Boom! Powerful Cosmic Explosion May Hint at How Black Holes Form:

Boom! Powerful Cosmic Explosion May Hint at How Black Holes Form
An artist's illustration of a gamma-ray burst, an energetic blast of jets that fly at nearly the speed of light from a massive star collapsing into a black hole. New research has revealed more about how the blasts are generated and how they evolve over time.
Credit: NASA's Goddard Space Flight Center

An ultrapowerful, superfast explosion in space is providing new insight into how dying stars turn into black holes.

An international team of researchers looked at a gamma-ray explosion called GRB 160625B that brightened the sky in June 2016. Gamma-ray bursts are among the most powerful explosions in the universe, but they are typically tough to track because they are very short-lived (sometimes lasting just a few milliseconds).

"Gamma-ray bursts are catastrophic events, related to the explosion of massive stars 50 times the size of our sun," said Eleonora Troja, lead author of the new study and an assistant research scientist in astronomy at University of Maryland. "If you ranked all the explosions in the universe based on their power, gamma-ray bursts would be right behind the Big Bang." [Record Breaking Gamma-Ray Burst Captured By Fermi (Video)]

"In a matter of seconds, the process can emit as much energy as a star the size of our sun would in its entire lifetime," Troja said in a statement. "We are very interested to learn how this is possible."

Two key findings emerged from the observations, gathered using several ground- and space-based telescopes. The first step was better model what happens as the dying star collapses. The data suggests that the black hole creates a strong magnetic field that initially overwhelms jets of matter and energy formed because of the explosion. Then, the magnetic field breaks down, the study authors said.

In the next phase, the magnetic field diminishes, allowing matter to dominate the jets. Before, scientists thought that jets could be dominated only by the magnetic field or matter — not both.

Another insight concerns what kind of radiation is responsible for the bright phase at the beginning of the burst, which astronomers call the "prompt" phase. Before, several types of radiation were considered, including so-called blackbody radiation (heat emission from an object) and inverse Compton radiation (which happens when accelerated particles transfer energy to photons), according to the statement.

It turns out that a phenomenon called synchrotron radiation is behind the prompt phase. This kind of radiation happens when electrons accelerate in a curved or spiral pathway, propelled along by an organized magnetic field.

"Synchrotron radiation is the only emission mechanism that can create the same degree of polarization and the same spectrum we observed early in the burst," Troja said.

The fading afterglow of GRB 160625B, a gamma-ray burst recorded in June 2016. Here, data from Arizona State University's Reionization And Transients Infrared (RATIR) camera, on a telescope at Mexico's National Astronomical Observatory in Baja California, shows the burst from June 26 to Aug. 20, 2016.
Credit: Nathaniel Butler/ASU

"Our study provides convincing evidence that the prompt gamma-ray burst emission is driven by synchrotron radiation," she added. "This is an important achievement because, despite decades of investigation, the physical mechanism that drives gamma-ray bursts had not yet been unambiguously identified."

Gathering information about GRB 160625B required many telescopes to work together quickly. NASA's Fermi Gamma-ray Space Telescope first saw the explosion, and the ground-based Russia's MASTER-IAC telescope, which is located at the Teide Observatory in Spain's Canary Islands, quickly joined with observations in optical light.

MASTER-IAC's observations were key to understanding the evolution of GRB 160625B's magnetic field, the research team said. The magnetic field can influence polarized light (light waves that vibrate in a single plane) emanating from the burst. In a rare achievement, the telescope measured the proportion of polarized light to total light through almost the entire explosion.

"There is very little data on polarized emission from gamma-ray bursts. This burst was unique because we caught the polarization state at an early stage," said study co-author Alexander Kutyrev, an associate astronomy research scientist at the University of Maryland and an associate scientist at NASA's Goddard Space Flight Center.

"This is hard to do because it requires a very fast reaction time, and there are relatively few telescopes with this capability," Kutyrev added. "This paper shows how much can be done, but to get results like this consistently, we will need new rapid-response facilities for observing gamma-ray bursts."

Other participating telescopes included NASA's Swift Gamma-ray Burst Mission (X-ray and ultraviolet), the multi-institution Reionization and Transient Infrared/Optical Project camera (at Mexico's National Astronomical Observatory in Baja California), the National Radio Astronomy Observatory's Very Large Array in New Mexico, and the Commonwealth Scientific Industrial Research Organisation's Australia Telescope Compact Array.

The new research was detailed today (July 26) in the journal Nature.

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MARS - Ancient Volcanoes on Mars Could Have Been the Place for Life

Ancient Volcanoes on Mars Could Have Been the Place for Life:

For decades, Mars has been the focal point of intense research. Beginning in the 1960s, literally dozens of robotic spacecraft, orbiters and rovers have explored Mars’ atmosphere and surface, looking for clues to the planet’s past. From this, scientists now know that billions of years ago, Mars was a warmer, wetter place. Not only did liquid water exist on its surface, but it is possible life existed there in some form as well.

Granted, some recent findings have cast some doubt in this, indicating that Mars’ surface may have been hostile to microbes. But a new study from an international team of scientists indicates that evidence life could be found in volcanic deposits. Specifically, they argue that within the massive geological structure known as Valles Marineris, there may be ancient volcanoes that have preserved ancient microbes.

The study, titled “Amazonian Volcanism Inside Valles Marineris on Mars“, recently appeared in the journal Earth and Planetary Science Letters. Led by Petr Brož of the Institute of Geophysics at the Czech Academy of Sciences (AVCR), the team examined Mars’ famous Valles Marineris region – a canyon system stretching for 4000 km (2485.5 mi) – for signs of recent geological activity, which opens up the possibility of there also being fossilized life there.

Valles Marineris, part of NASA World Wind map of Mars. Credit: NASA
The team began by examining the Coprates Chasma canyon, one of the lowest points in Valles Marineris, which is home to over 130 volcanoes and solidified lava flows. This consisted of analyzing high-resolution images of the region that were taken by NASA’s Mars Reconnaissance Orbiter (MRO), which revealed cones of basaltic lava (aka. scoria) and ash that measured around 400-meters (1300 ft) high.

After examining the cones’ surface patterns and morphological details, they confirmed that these were indeed the remains of lava volcanoes (and not mud volcanoes, which was another possibility). In addition, they also noted similarities between these cone and others on Mars where mud volcanism is not possible – as well as similarities with volcanic cones here on Earth.

As Ernst Hauber, a researcher from the Institute of Planetary Research at the German Aerospace Center (DLR) and a co-author on the study, explained in a AVCR press release:

“The spatial distribution of the cones also suggests their volcanic origin. They appear to occur more frequently along tectonic fractures that formed the trough in the surface and whose fracture interfaces continue into the subsurface, creating pathways for the magma to ascend.”
Even more surprising was the apparent age of the volcanoes, which was very young. On Mars, the main period of volcanic activity ended during Mars’ Hesperian Period – which ran from 3.7 to approximately 3.0 billion years ago. And while images acquired by the Mars Express mission have shown indications of younger volcanoes (occurring 500 million years ago), these tend to be located in volcanic provinces.

A colorized image of the surface of Mars taken by the Mars Reconnaissance Orbiter. The line of three volcanoes is the Tharsis Montes, with Olympus Mons to the northwest. Valles Marineris is to the east. Image: NASA/JPL-Caltech/ Arizona State University

A colorized image of the surface of Mars taken by the Mars Reconnaissance Orbiter. The line of three volcanoes is the Tharsis Montes, with Olympus Mons to the northwest. Valles Marineris is to the east. Image: NASA/JPL-Caltech/ Arizona State University
A good example of this is the Tharsis Bulge, which is located several thousand km from the Coprates Chasma canyon. It is here that the Tharses Montes mountain chain is located, which consists of the shield volcanoes of Ascraeus Mons, Pavonis Mons and Arsia Mons. Olympus Mons, the tallest mountain in the Solar System (with an elevation of 22 km or 13.6 mi), is located at the edge of this region.

In contrast, the volcanic cones spotted in the Coprates Chasma canyon were estimates to be between 200 and 400 million years of age, placing them in the most recent geological period known as the Amazonian (3.0 billion years ago to the present day). This effectively demonstrates that these volcanoes formed late in Mars’ history and far away from volcanic areas like Tharsis and Elysium.

It also demonstrates that these volcanoes were not part of the original formation of Valles Marineris, which is believed to be related to the formation of the Tharsis Bulge. This all took place between the Noachian to Late Hesperian periods of Mars (ca. 3.5 billion years ago), which was the last time Mars experienced widespread geological activity.

Last, but not least, the team used the Compact Reconnaissance Imaging Spectrometer (CRISM) aboard the MRO to learn more about the mineral compositions of the region’s lava and volcanic cones. Once again, their findings proved to be surprising, and could indicate that the Coprates Chasma region is a suitable location to search for evidence of ancient life on Mars.

Image of young volcanoes at the base of Coprates Chasma on Mars, obtained by the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona
Essentially, the CRISM data indicated the presence of high-silica content minerals in the volcanic rock, which included opaline-like substances at one of the peaks. Opaline silicates, it should be noted, are water-bearing materials that are often produced by hydrothermal processes – where silicate structures form from supersaturated, hot solutions of minerals that cool to become solid.

On Earth, microorganisms are often found within opal deposits since they form in energy and mineral-rich environments, where microbial lifeforms thrive. The presence of these minerals in the Coprates Chasma region could therefore mean that ancient microorganisms once thrived there. Moreover, such organisms could also be fossilized within the mineral-rich lava rock, making it a tempting target for future research.

As Hauber indicated, the appeal of Coprates Chasma doesn’t end there, and future mission will surely want to make exploring this region a priority:

“Coprates Chasma is not just interesting with regard to the question of previous life on Mars. The region would also be an excellent landing site for future Mars Rovers. Here we could investigate many scientifically important and interesting topics. Analyzing samples for their elemental isotopic fractions would allow us to determine with far greater precision when the volcanoes were actually active.

“On the towering, steep walls, the geologic evolution of the Valles Marineris is presented to us almost like a history book – gypsum strata and layers of old, crustal rocks can be observed, as well as indications for liquid water trickling down the slopes even today during the warm season. That is as much Mars geology as you can get!”

Scientists were able to gauge the rate of water loss on Mars by measuring the ratio of water and HDO from today and 4.3 billion years ago. Credit: Kevin Gill
In other words, this low-lying region could be central to future studies that attempt to unlock the history and geological evolution of the Red Planet. The payoffs of studying this region not only include determining if Mars had life in the past, but when and how it went from being a warmer, wetter environment to the cold, dessicated landscape we know today.

In the future, NASA, the ESA, the China National Space Agency (CNSA) and Roscosmos all hope to mount additional robotic missions to Mars. In addition, NASA and even SpaceX hope to send crewed missions to the planet in the hopes of learning more about its past – and possibly future – habitability. Between its geological history, greater atmospheric pressure, and the possibility of fossilized life, one or more of these missions may be headed to Valles Marineris to have a look around.

Further Reading: The Czech Academy of Science, Earth and Planetary Science Letters

The post Ancient Volcanoes on Mars Could Have Been the Place for Life appeared first on Universe Today.

MINI-SHUTTLE Dream Chaser Mini-Shuttle to Fly ISS Resupply Missions on ULA Atlas V

Dream Chaser Mini-Shuttle to Fly ISS Resupply Missions on ULA Atlas V:

Artist’s concept of the Sierra Nevada Corporation Dream Chaser spacecraft launching atop the United Launch Alliance Atlas V rocket in the 552 configuration on cargo missions to the International Space Station. Credit: ULA
The first two missions of the unmanned Dream Chaser mini-shuttle carrying critical cargo to the International Space Station (ISS) for NASA will fly on the most powerful version of the Atlas V rocket and start as soon as 2020, announced Sierra Nevada Corporation (SNC) and United Launch Alliance (ULA).

“We have selected United Launch Alliance’s Atlas V rocket to launch our first two Dream Chaser® spacecraft cargo missions,” said SNC of Sparks, Nevada.

Dream Chaser will launch atop the commercial Atlas V in its most powerful configuration, dubbed Atlas V 552, with five strap on solid rocket motors and a dual engine Centaur upper stage while protectively tucked inside a five meter diameter payload fairing – with wings folded.

Blast off of Dream Chaser loaded with over 5500 kilograms of cargo mass for the space station crews will take place from ULA’s seaside Space Launch Complex-41 on Cape Canaveral Air Force Station in Florida.

Sierra Nevada Corporation’s Dream Chaser spacecraft docks at the International Space Station.
Credits: Sierra Nevada Corporation
The unique lifting body design enables runway landings for Dream Chaser, similar to the NASA’s Space Shuttle at the Shuttle Landing Facility runway at NASA’s Kennedy Space Center in Florida.

The ULA Atlas V enjoys a 100% success rate. It has also been chosen by Boeing to ferry crews on piloted missions of their CST-100 Starliner astronaut space taxi to the ISS and back. The Centaur upper stage will be equipped with two RL-10 engines for both Dream Chaser and Starliner flights.

“SNC recognizes the proven reliability of the Atlas V rocket and its availability and schedule performance makes it the right choice for the first two flights of the Dream Chaser,” said Mark Sirangelo, corporate vice president of SNC’s Space Systems business area, in a statement.

“Humbled and honored by your trust in us,” tweeted ULA CEO Tory Bruno following the announcement.

Liftoff of the maiden pair of Dream Chaser cargo missions to the ISS are expected in 2020 and 2021 under the Commercial Resupply Services 2 (CRS2) contract with NASA.

Rendering of Launch of SNC’s Dream Chaser Cargo System Aboard an Atlas V Rocket. Credit: SNC
“ULA is pleased to partner with Sierra Nevada Corporation to launch its Dream Chaser cargo system to the International Space Station in less than three years,” said Gary Wentz, ULA vice president of Human and Commercial Systems.

“We recognize the importance of on time and reliable transportation of crew and cargo to Station and are honored the Atlas V was selected to continue to launch cargo resupply missions for NASA.”

By utilizing the most powerful variant of ULA’s Atlas V, Dream Chaser will be capable of transporting over 5,500 kilograms (12,000 pounds) of pressurized and unpressurized cargo mass – including science experiments, research gear, spare part, crew supplies, food, water, clothing and more per ISS mission.

“In addition, a significant amount of cargo, almost 2,000 kilograms is directly returned from the ISS to a gentle runway landing at a pinpoint location,” according to SNC.

“Dream Chaser’s all non-toxic systems design allows personnel to simply walk up to the vehicle after landing, providing immediate access to time-critical science as soon as the wheels stop.”

“ULA is an important player in the market and we appreciate their history and continued contributions to space flights and are pleased to support the aerospace community in Colorado and Alabama,” added Sirangelo.

Under the NASA CRS-2 contract awarded in 2016, Dream Chaser becomes the third ISS resupply provider, joining the current ISS commercial cargo vehicle providers, namely the Cygnus from Orbital ATK of Dulles, Virginia and the cargo Dragon from SpaceX of Hawthorne, California.

NASA decided to plus up the number of ISS commercial cargo providers from two to three for the critical task of ensuring the regular delivery of critical science, crew supplies, provisions, spare parts and assorted gear to the multinational crews living and working aboard the massive orbiting outpost.

NASA’s CRS-2 contracts run from 2019 through 2024 and specify six cargo missions for each of the three commercial providers.

By adding a new third provider, NASA simultaneously gains the benefit of additional capability and flexibility and also spreads out the risk.

Both SpaceX and Orbital ATK suffered catastrophic launch failures during ISS resupply missions, in June 2015 and October 2014 respectively, from which both firms have recovered.

Orbital ATK and SpaceX both successfully launched ISS cargo missions this year. Indeed a trio of Orbital ATK Cygnus spacecraft have already launched on the Atlas V, including the OA-7 resupply mission in March 2017.

Orbital ATK’s seventh cargo delivery flight to the International Space Station -in tribute to John Glenn- launched at 11:11 a.m. EDT April 18, 2017, on a United Launch Alliance Atlas V rocket from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida. Credit: Ken Kremer/
Unlike the Cygnus which burns up on reentry and Dragon which lands via parachutes, the reusable Dream Chaser is capable of low-g reentry and runway landings. This is very beneficial for sensitive scientific experiments and allows much quicker access by researchers to time critical cargo.

1st Reused SpaceX Dragon cargo craft lifts off from Launch Complex 39A at NASA’s Kennedy Space Center in Florida at 5:07 p.m. June 3, 2017 on CRS-11 mission carrying 3 tons of research equipment, cargo and supplies to the International Space Station. Credit: Ken Kremer/
Dream Chaser has been under development for more than 10 years. It was originally developed as a manned vehicle and a contender for NASA’s commercial crew vehicles. When SNC lost the bid to Boeing and SpaceX in 2014, the company opted to develop this unmanned variant instead.

A full scale test version of the original Dream Chaser is currently undergoing ground tests at NASA’s Armstrong Flight Research Center in California. Approach and landing tests are planned for this fall.

Other current cargo providers to the ISS include the Russian Progress and Japanese HTV vessels.

Watch for Ken’s onsite space mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Scale models of NASA’s Commercial Crew program vehicles and launchers; Boeing CST-100, Sierra Nevada Dream Chaser, SpaceX Dragon. Credit: Ken Kremer/

Sierra Nevada Dream Chaser engineering test article in flight during prior captive-carry tests. Credit: NASA
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EARTH ORBIT - Ready to Leave Low Earth Orbit? Prototype Construction Begins for a Deep Space Habitat

Ready to Leave Low Earth Orbit? Prototype Construction Begins for a Deep Space Habitat:

In 2010, NASA accounted its commitment to mount a crewed mission to Mars by the third decade of the 21st century. Towards this end, they have working hard to create the necessary technologies – such as the Space Launch System (SLS) rocket and the Orion spacecraft. At the same time, they have partnered with the private sector to develop the necessary components and expertise needed to get crews beyond Earth and the Moon.

To this end, NASA recently awarded a Phase II contract to Lockheed Martin to create a new space habitat that will build on the lessons learned from the International Space Station (ISS). Known as the Deep Space Gateway, this habitat will serve as a spaceport in lunar orbit that will facilitate exploration near the Moon and assist in longer-duration missions that take us far from Earth.

The contract was awarded as part of the Next Space Technologies for Exploration Partnership (NextSTEP) program, which NASA launched in 2014. In April of 2016, as part of the second NextSTEP Broad Agency Announcement (NextSTEP-2) NASA selected six U.S. companies to begin building full-sized ground prototypes and concepts for this deep space habitat.

Artist’s impression of the Deep Space Gateway, currently under development by Lockheed Martin. Credit: NASA
Alongside such well-known companies like Bigelow Aerospace, Orbital ATK and Sierra Nevada, Lockheed Martin was charged with investigating habitat designs that would enhance missions in space near the Moon, and also serve as a proving ground for missions to Mars. Intrinsic to this is the creation of something that can take effectively integrate with SLS and the Orion capsule.

In accordance with NASA’s specifications on what constitutes an effective habitat, the design of the Deep Space Gateway must include a pressurized crew module, docking capability, environmental control and life support systems (ECLSS), logistics management, radiation mitigation and monitoring, fire safety technologies, and crew health capabilities.

The design specifications for the Deep Space Gateway also include a power bus, a small habitat to extend crew time, and logistics modules that would be intended for scientific research. The propulsion system on the gateway would rely on high-power electric propulsion to maintain its orbit, and to transfer the station to different orbits in the vicinity of the Moon when required.

With a Phase II contract now in hand, Lockheed Martin will be refining the design concept they developed for Phase I. This will include building a full-scale prototype at the Space Station Processing Facility at NASA’s Kennedy Space Center at Cape Canaveral, Florida, as well as the creation of a next-generation Deep Space Avionics Integration Lab near the Johnson Space Center in Houston.

Artist’s concept of space habitat operating beyond Earth and the Moon. Credit: NASA
As Bill Pratt, Lockheed Martin’s NextSTEP program manager, said in a recent press statement:

“It is easy to take things for granted when you are living at home, but the recently selected astronauts will face unique challenges. Something as simple as calling your family is completely different when you are outside of low Earth orbit. While building this habitat, we have to operate in a different mindset that’s more akin to long trips to Mars to ensure we keep them safe, healthy and productive.”
The full-scale prototype will essentially be a refurbished Donatello Multi-Purpose Logistics Module (MPLM), which was one of three large modules that was flown in the Space Shuttle payload bay and used to transfer cargo to the ISS. The team will also be relying on “mixed-reality prototyping”, a process where virtual and augmented reality are used to solve engineering issues in the early design phase.

“We are excited to work with NASA to repurpose a historic piece of flight hardware, originally designed for low Earth orbit exploration, to play a role in humanity’s push into deep space,” said Pratt. “Making use of existing capabilities will be a guiding philosophy for Lockheed Martin to minimize development time and meet NASA’s affordability goals.”

The Deep Space Gateway will also rely on the Orion crew capsule’s advanced capabilities while crews are docked with the habitat. Basically, this will consist of the crew using the Orion as their command deck until a more permanent command module can be built and incorporated into the habitat. This process will allow for an incremental build-up of the habitat and the deep space exploration capabilities of its crews.

Credit: NASA
As Pratt indicated, when uncrewed, the habitat will rely on systems that Lockheed Martin has incorporated into their Juno and MAVEN spacecraft in the past:

“Because the Deep Space Gateway would be uninhabited for several months at a time, it has to be rugged, reliable and have the robotic capabilities to operate autonomously. Essentially it is a robotic spacecraft that is well-suited for humans when Orion is present. Lockheed Martin’s experience building autonomous planetary spacecraft plays a large role in making that possible.”
The Phase II work will take place over the next 18 months and the results (provided by NASA) are expected to improve our understanding of what is needed to make long-term living in deep space possible. As noted, Lockheed Martin will also be using this time to build their Deep Space Avionics Integration Laboratory, which will serve as an astronaut training module and assist with command and control between the Gateway and the Orion capsule.

Beyond the development of the Deep Space Gateway, NASA is also committed to the creation of a Deep Space Transport – both of which are crucial for NASA’s proposed “Journey to Mars”. Whereas the Gateway is part of the first phase of this plan – the “Earth Reliant” phase, which involves exploration near the Moon using current technologies – the second phase will be focused on developing long-duration capabilities beyond the Moon.

NASA’s Journey to Mars. NASA is developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s. Credit: NASA/JPL
For this purpose, NASA is seeking to create a reusable vehicle specifically designed for crewed missions to Mars and deeper into the Solar System. The Deep Space Transport would rely on a combination of Solar Electric Propulsion (SEP) and chemical propulsion to transport crews to and from the Gateway – which would also serve as a servicing and refueling station for the spacecraft.

This second phase (the “Proving Ground” phase) is expected to culminate at the end of the 2020s, at which time a one-year crewed mission will take place. This mission will consist of a crew being flown to the Deep Space Gateway and back to Earth for the purpose of validating the readiness of the system and its ability to conduct long-duration missions independent of Earth.

This will open the door to Phase Three of the proposed Journey, the so-called “Earth Indepedent” phase. At this juncture, the habitation module and all other necessary mission components (like a Mars Cargo Vehicle) will be transferred to an orbit around Mars. This is expected to take place by the early 2030s, and will be followed (if all goes well) by missions to the Martian surface.

While the proposed crewed mission to Mars is still a ways off, the architecture is gradually taking shape. Between the development of spacecraft that will get the mission components and crew to cislunar space – the SLS and Orion – and the development of space habitats that will house them, we are getting closer to the day when astronauts finally set foot on the Red Planet!

Further Reading: NASA, Lockheed Martin

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