Author: jappe

A cosmic butterfly of a nebula is undergoing a stunning metamorphosis in space, according to new images from a telescope in Chile.

The celestial view, captured by the European Southern Observatory’s Very Large Telescope, is actually the result of dust spit out of a dying star that is then shaped by a stellar companion to form what looks like a bipolar planetary nebula with symmetrical wings. ESO scientists also created a video view of the butterfly-like nebula to showcase the new images.

The images offer a rare glimpse into the intricacies of this type of nebula formation, which scientists still know little about. In this case, it looks like the transition is just getting started, ESO officials explained. [Strange Nebula Shapes: What Do You See? (Gallery)]

What looks like a celestial butterfly here is actually the work of material from the red giant star L2 Puppis being shaped by a companion star into its gossamer state. The European Southern Observatory’s Very Large Telescope in Chile captured this image.
Credit: Credit: ESO/P. Kervella

The new ESO images are centered on L2 Puppis, an aging red giant star about 200 light-years from Earth. The star is surrounded by a disk of dust (viewed head-on in the photographs) that extends outward across 550 million miles, (900 million kilometers). Cones of dust form the beginnings of butterfly wings as they stretch out upward and downward, perpendicular to the disk, with curving plumes flying out through their centers. Its companion star, a younger red giant, orbits it very quickly, about once every few years.

“The origin of bipolar planetary nebulae is one of the great classic problems of modern astrophysics, especially the question of how, exactly, stars return their valuable payload of metals back into space — an important process, because it is this material that will be used to produce later generations of planetary systems,” study lead author Pierre Kervella, of Unidad Mixta Internacional Franco-Chilena de Astronomía in France said in a statement. “With the companion star orbiting L2 Puppis only every few years, we expect to see how the companion star shapes the red giant’s disk. It will be possible to follow the evolution of the dust features around the star in real time — an extremely rare and exciting prospect.”

This image of the L2 Puppis “celestial butterfly” is built from visible and infrared observations of the Very Large Telescope to show the dust surrounding the red giant star.
Credit: Credit: ESO/P. Kervella

The new view of L2 Puppis is made even clearer by the Very Large Telescope’s SPHERE instrument, which has a mode that enhances faint details that would normally be overshadowed by the bright star. The result is an image three times sharper than one from the Hubble Space Telescope which also helps build a 3D model of the structures based on how they polarize nearby light.

Hubble has imaged many of these nebulas over the years, though never this young, and scientists have long puzzled over their orientation and formation: whether the dust is pressed inward or pulled outward by a companion into its distinctive shape. One theory suggests that the gas ejected by the dying star is pushed down into a disk shape by the emissions of the other star, and as the star sheds the rest of its atmosphere it is funneled outward through that ring in long plumes.

This wide view image from the European Southern Observatory’s Digital Sky Survey shows the region around the red giant star L2 Puppis, which is about 200 light-years from Earth.
Credit: Credit: ESO/Digitized Sky Survey 2

Another theory suggests that the companion star draws a lot of material away from the central star into a disk surrounding it and fast jets blast out from the center, carving out space in the surrounding dust cloud. The system’s appearance is consistent with both of those theories, and spotting it in this early form offers astronomers a unique opportunity to watch the butterfly bloom.

You can follow staff writer Sarah Lewin on Twtter at @SarahExplains. Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.

This image from a pilot project, the Deep Lens Survey (DLS), offers up an example of what the sky will look like when observed by LSST. The images from LSST will have twice DLS’ depth and resolution, while also covering 50,000 times the area of this particular image, and in six different optical colors. Credit: Deep Lens Survey / UC Davis / NOAO

Adam Hadhazy, writer and editor for The Kavli Foundation, contributed this article to Space.com’s Expert Voices: Op-Ed & Insights.

During a traditional Chilean stone-laying ceremony, the first building block of a powerful new astronomical observatory, the Large Synoptic Survey Telescope (LSST), was placed in the ground on Cerro Pachón in Chile April 14. Although LSST will not see first light until 2022, the astronomical community is already abuzz about how this ambitious project will open up the “dark universe” of dark matter and dark energy as never before. That mysterious substance and force make up 95 percent of the universe’s mass and energy, yet scientists are largely in the dark, as it were, about what they are. 

One of the keys to LSST’s potential is its 3.2 gigapixel camera, the biggest digital camera slated for construction to date. Another key is LSST’s comprehensive sweep of the heavens. Every few days, the telescope will survey the entire Southern Hemisphere’s sky. An astounding 30 terabytes of data will be collected nightly. After just a month of scanning the sky, LSST will have observed a greater share of the cosmos than all previous astronomical surveys combined.

On April 2, 2015, two astrophysicists and a theoretical physicist spoke with The Kavli Foundation about how LSST’s deep search for dark matter and dark energy  will answer fundamental questions about our universe’s composition. 

Steven Kahn — is the director of LSST and a natural sciences professor in the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) at Stanford University. He is an experimental astrophysicist with broad interests in instrumentation, observation and theory. 

Sarah Bridle — is a professor of astrophysics in the Extragalactic Astronomy and Cosmology research group of the Jodrell Bank Center for Astrophysics in the School of Physics and Astronomy at the University of Manchester. She has served as the project scientist for the United Kingdom’s proposal to join LSST and she presently is co-coordinator of the Weak Lensing Working Group of the Dark Energy Survey (DES), a precursor cosmological project to LSST. 

Hitoshi Murayama — is the director of the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) at the University of Tokyo and a professor at the Berkeley Center for Theoretical Physics at the University of California, Berkeley. His work as a theoretical physicist spans a wide range of topics including particle physics, dark matter and dark energy. Kavli IPMU is a partner in the Hyper Suprime-Cam project, another precursor to LSST.

The following is an edited transcript of their roundtable discussion. The participants have been provided the opportunity to amend or edit their remarks.

The Kavli Foundation: Steven, when the LSST takes its first look at the universe seven years from now, why will this be so exciting to you? 

Steven Kahn: In terms of how much light it will collect and its field of view, LSST is about ten times bigger than any other survey telescope either planned or existing. This is important because it will allow us to survey a very large part of the sky relatively quickly and to do many repeated observations of every part of the Southern Hemisphere over ten years. By doing this, the LSST will gather information on an enormous number of galaxies. We’ll detect something like 20 billion galaxies. 

Sarah Bridle: That’s a hundred times as many as we’re going to get with the current generation of telescopes, so it’s a huge increase. With the data, we’re going to be able to make a three-dimensional map of the dark matter in the universe using gravitational lensing. Then we’re going to use that to tell us about how the “clumpiness” of the universe is changing with time, which is going to tell us about dark energy.

TKF: How does gathering information on billions of galaxies help us learn more about dark energy?

Hitoshi Muryama: Dark energy is accelerating the expansion of the universe and ripping it apart. The questions we are asking are: Where is the universe going? What is its fate? Is it getting completely ripped apart at some point? Does the universe end? Or does it go forever? Does the universe slow down at some point? To understand these questions, it’s like trying to understand how quickly the population of a given country is aging. You can’t understand the trend of where the country is going just by looking at a small number of people. You have to do a census of the entire population. In a similar way, you need to really look at a vast amount of galaxies so you can understand the trend of where the universe is going. We are taking a cosmic census with LSST.

What is weak gravitational lensing? This phenomenon occurs when foreground matter and dark matter contained in galaxy clusters bend the light from background galaxies — sort of like looking through the bottom of a wine glass. Measuring the amount of the distortion of the background galaxies indirectly reveals the amount of dark matter that has clumped together in the foreground object. Measuring the rate of this dark matter clumping across different eras in the universe’s history speaks to how much dark energy is stretching the universe at given times, thus revealing the mysterious, pervasive force’s strength and properties. This diagram explains the phenomenon of gravitational lensing. Foreground clumps of dark matter in galaxy clusters gravitationally bend the Earth-bound light from background galaxies. Note that the image is not to scale.
Credit: NASA, ESA, L. Calcada

TKF: The main technique the LSST will use to learn more about dark energy will be gravitational lensing (see sidebar). Dark energy is the mysterious, invisible force that is pushing open and shaping the universe. Can you elaborate on why this is important and how will LSST help realize its full potential? 

S.B.: It’s extremely difficult to detect the dark energy that seems to be causing our universe to accelerate. Through gravitational lenses, however, it’s possible by observing how much dark matter is being pulled together by gravity. And by looking at how much this dark matter clumps up early and later on in the universe, we can see how much the universe is being stretched apart at different times. With LSST, there will be a huge increase in the number of galaxies that we can detect and observe. LSST will also let us identify how far away the galaxies are. This is important. If we want to see how fast the universe is clumping together at different times, we need to know at what time and how far away we’re looking.

S.K.: With LSST, we’re trying to measure the subtle distortion of the appearance of galaxies caused by clumps of dark matter. We do this by looking for correlations in galaxies’ shapes depending on their position with respect to one another. Of course, there’s uncertainty associated with that kind of measurement on the relatively small scales of individual galaxies, and the dominant source of that uncertainty is that galaxies have intrinsic shapes—some are spiral-shaped, some are round, and so on, and we are seeing them at different viewing angles, too. Increasing the number of galaxies with LSST makes doing this a far more statistically powerful and thus precise measurement of the effect of gravitational lensing caused by dark matter and how the clumping of dark matter has changed over the universe’s history.

LSST will also help address something called cosmic variance. This happens when we’re making comparisons of what we see against a statistical prediction of what an ensemble of possible universes might look like. We only live in one universe, so there’s an inherent error associated with how good those statistical predictions are of what our universe should look like when applied to the largest scales of great fields of galaxies. The only way to try and statistically beat that cosmic variance down is to survey as much of the sky as possible, and that’s the other area where LSST is breaking new ground.

Steven Kahn
Credit: Steven Kahn

TKF: Will the gravitational lensing observations by LSST be more accurate than anything before?

S.K.: One of the reasons I personally got motivated to work on LSST was because of the difficulty in making the sort of weak lensing measurements that Sarah described.

S.B.: Typically, telescopes distort the images of galaxies by more than the gravitational lensing effect we are trying to measure. And in order to learn about dark matter and dark energy from gravitational lensing, we’ve got to not just detect the gravitational lensing signal but measure it to about a one-percent accuracy. So we’ve got to rid of these effects from the optics in the telescope before we can do anything to learn about cosmology.

S.K.: A lot of the initial work in this field has been plagued by issues associated with the basic telescopes and cameras used. It was hard to separate out the cosmic signals that people were looking for from spurious effects that were introduced by the instrumentation. LSST is actually the first telescope that will have ever been built with the notion of doing weak lensing in mind.  We have taken great care to model in detail the whole system, from the telescope to the camera to the atmosphere that we are looking through, to understand the particular issues in the system that could compromise weak lensing measurements. That approach has been a clear driver in how we design the facility and how we calibrate it. It’s been a big motivation for me personally and for the entire LSST team.

TKF: As LSST reveals the universe’s past, will it also help us predict the future of the universe?

H.M.: Yes, it will. Because LSST will survey the sky so quickly and repeatedly, it will show how the universe is changing over time. For example, we will be able to see how a supernova changes from one time period to another. This kind of information should prove extremely useful in deciphering the nature of dark energy , for instance.

S.K.: This is one way LSST will observe changes in the universe and gather information on dark energy beyond gravitational lensing. In fact, the way the acceleration of the universe by dark energy was first discovered in 1998 was through the measurement of what are called Type Ia supernovae. These are exploding stars where we believe we understand the typical intrinsic brightness of the explosion. Therefore, the apparent brightness of a supernova — how faint the supernova appears when we see it — is a clear measure of how far away the object is. That is because objects that are farther away are dimmer than closer objects. By measuring a population of Type Ia supernovae, we can figure out their true distances from us and how those distances have increased over time. Put those two pieces of information together, and that’s a way of determining the expansion rate of the universe. 

This analysis was done for the initial discovery of the accelerating cosmic expansion with a relatively small number of supernovae — just tens. LSST will measure an enormous number of supernovae, something like 250,000 per year. Only a smaller fraction of those will be very well characterized, but that number is still in the tens of thousands per year. That will be very useful for understanding how our universe has evolved.

TKF: LSST will gather a prodigious amount of data. How will this information be made available to scientists and the public alike for parsing?

S.K.: Dealing with the enormous size of the data base LSST will produce is a challenge. Over its ten-year run, LSST will generate something like a couple hundred petabytes of data, where a petabyte is 10-to-the-15th bytes. That’s more data, by a lot, than everything that’s ever been written in any language in human history. 

The data will be made public to the scientific community largely in the form of catalogs of objects and their properties. But those catalogs can be trillions of lines long. So one of the challenges is not so much how you acquire and store the data, but how do you actually find anything in something that big? It’s the needle in the haystack problem. That’s where there need to be advances because the current techniques that we use to query catalogs, or to say “find me such and such,” they don’t scale very well to this size of data. So a lot of new computer science ideas have to be invoked to make that work. 

Hitoshi Murayama
Credit: Hitoshi Murayama

H.M.: One thing that we at Kavli IPMU are pursuing right now is a sort of precursor project to LSST called Hyper Suprime-Cam, using the Subaru Telescope. It’s smaller than LSST, but it’s trying to do many of the things that LSST is after, like looking for weak gravitational lensing and trying to understand dark energy. We already are facing the challenge of dealing with a large data set. One aspect we would like to pursue at Kavli IPMU, and of course LSST is already doing it, is to get a lot of people in computer science and statistics involved into this. I believe a new area of statistics will be created by the needs of handling these large data sets. It’s a sort of fusion, the interdisciplinary aspects of this project. It’s a large astronomy survey that will influence other areas of science. 

TKF: Are any “citizen science” projects envisioned for LSST, like Galaxy Zoo, a website where astronomy buffs classify the shapes of millions of galaxies imaged by the Sloan Digital Sky Survey?

S.K.: Data will be made available right away. So LSST will in some sense bring the universe home to anybody with a personal computer, who can log on and look at any part of the southern hemisphere’s sky at any given time. So there’s a tremendous potential there to engage the public not only in learning about science, but actually in doing science and interacting directly with the universe. 

We have people involved in LSST that are intimately tied into Galaxy Zoo. We’re looking into how to incorporate citizens and crowdsource the science investigations of LSST. One of these investigations is strong gravitational lensing. Sarah has talked about weak gravitational lensing, which is a very subtle distortion to the appearance of the background galaxies. But it turns out if you put a galaxy right behind a concentration of dark matter found in a massive foreground galaxy cluster, then the distortions can get very significant. You can actually see multiple images of the background galaxy in a single image, bent all the way around the foreground galaxy cluster. The detection of those strong gravitational lenses and the analysis of the light patterns you see within them also yields complementary scientific information about cosmological fundamental parameters. But it requires sort of recognizing what is in fact a strong gravitational lensing event, as well as modeling the distribution of dark matter that gives rise to the strength of that particular lensing. Colleagues of Hitoshi and myself have already created a tool to help with this effort, called SpaceWarps (www.spacewarps.org). The tool lets the public look for strong gravitational lenses using data from the Sloan Digital Sky Survey and to play around with dark matter modeling to see if they can get something that looks like the real data. 

H.M.: This has been incredibly successful. Scientists have developed computer programs to automatically look for these strongly lensed galaxies, but even an algorithm written by the best scientists can still miss some of these strong gravitationally lensed objects. Regular citizens, however, often manage to find some candidates for the strongly lensed galaxies that the computer algorithm has missed. Not only will this be great fun for people to get involved, it can even help the science as well, especially with a project as large as LSST.

TKF: In the hunt for dark energy’s signature on the cosmos, LSST is just one of many current and planned efforts. Sarah, how will LSST observations tie in with the Dark Energy Survey you’re working on, and Hitoshi, with will LSST complement the Hyper Suprime-Cam? 

S.B.: So the Dark Energy Survey is going to image one-eighth of the whole sky and have 300 million galaxy images. About two years of data have been taken so far, with about three more years to go. We’ll be doing maps of dark matter and measurements of dark energy. The preparation for LSST that we are doing via DES will be essential.

H.M.: Hyper Suprime-Cam is similar to the Dark Energy Survey. It’s a nearly billion pixel camera looking for nearly 10 million galaxies. Following up on the Hyper Suprime-Cam imaging surveys, we would like to measure what we call spectra from a couple million galaxies. 

S.K.: The measurement of spectra as an addition to imaging tells us not only about the structure of matter in the universe but also how much the matter is moving with respect to the overall, accelerating cosmic expansion due to dark energy. Spectra are an additional, very important piece of information in constraining cosmological models. 

H.M.: We will identify spectra with an instrument called the Prime Focus Spectrograph, which is scheduled to start operations in 2017 also on the Subaru telescope. We will do very deep exposures to get the spectra on some of these interesting objects, such as galaxies where lensing is taking place and supernovae, which will also allow us to do much more precise measurements on dark energy. 

Like the Hyper Suprime-Cam, LSST can only do imaging. So I’m hoping when LSST comes online in the 2020s, we will already have the Prime Focus Spectrograph operational, and we will be able to help each other. LSST’s huge amount of data will contain many interesting objects we would like to study with this Prime Focus Spectrograph.

S.K.: All these dark matter and dark energy telescope projects are very complementary to each other. It’s because of the scientific importance of these really fundamental pressing questions — what is the nature of dark matter and dark energy? — that the various different funding institutions around the world have been eager to invest in such an array of different complementary projects. I think that’s great, and it just shows how important this general problem is. 

TKF: Hitoshi, you mentioned earlier the interdisciplinary approach fostered by LSST and projects like it, and you’ve spoken before about how having different scientific disciplines and perspectives together leads to breakthrough thinking — a major goal of Kavli IPMU. Your primary expertise is in particle physics, but you work on many other areas of physics. Could you describe how observations of the very biggest scales of the dark universe with LSST will inform work on the very smallest, subatomic scales, and vice versa? 

H.M.: It’s really incredible to think about this point. The biggest thing we can observe in the universe has to have something to do with the smallest things we can think of and all the matter we see around us. 

Sarah Bridle
Credit: Sarah Bridle

S.B.: It is amazing that you can look at the largest scales and find out about the smallest things. 

H.M.: For more than a hundred years, particle physicists have been trying to understand what everything around us is made of. We made huge progress by building a theory called the standard model of particle physics in the 20th century, which is really a milestone of science. Discovering the Higgs boson at the Large Hadron Collider at CERN in 2012 really nailed that the standard model is the right theory about the origin of everything around us. But it turns out that what we see around us is actually making up only five percent of the universe. So there is this feeling among particle physicists of “what have we been doing for a hundred years?” We only have five percent of the universe! We still need to understand the remaining 95 percent of the universe, which is dark matter and dark energy. It’s a huge problem and we have no idea what they are really. 

A way I explain what dark matter is: It’s the mother from whom we got separated at birth. What I mean by this is without dark matter, there’s no structure to the universe — no galaxies, no stars—and we wouldn’t be here. Dark matter, like a mother, is the reason we exist, but we haven’t met her and have never managed to thank her. So that’s the reason why we would like to know who she is, how she came to exist and how she shaped us. That’s the connection between the science of looking for the fundamental constituents of the universe, which is namely what particle physicists are after, and this largest scale of observation done with LSST. 

TKF: Given LSST’s vast vista on the Universe, it is frankly expected that the project will turn up the unexpected. Any ideas or speculations on what tracking such a huge portion of the universe might newly reveal? 

S.K.: That’s sort of like asking, “what are the unknown unknowns?” [laughter]

TKF: Yes — good luck figuring those out!

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Credit: SPACE.com

S.K.: Let me just say, one of the great things about astrophysics is that we have explicit theoretical predictions we’re trying to test out by taking measurements of the universe. That approach is more akin to many other areas of experimental physics, like searching for the Higgs boson with the Large Hadron Collider, as Hitoshi mentioned earlier. But there’s also this wonderful history in astronomy that every time we build a bigger and better facility, we always find all kinds of new things we never envisioned. 

If you go back — unfortunately I’m old enough to remember these days — to the period before the launch of the Hubble Space Telescope, it’s interesting to see what people had thought were going to be the most exciting things to do with Hubble. Many of those things were done and they were definitely exciting. But I think what many people felt was the most exciting was the stuff we didn’t even think to ask about, like the discovery of dark energy Hubble helped make. So I think a lot of us have expectations of similar kinds of discoveries for facilities like LSST. We will make the measurement we’re intending to make, but there will be a whole bunch of other exciting stuff that we never even dreamed of that’ll come for free on top.

S.B.: I’m a cosmologist and I’m very excited for what LSST is going to do for cosmology, but I’m even more excited that it’s going to be taking very, very short 15-second exposures of the sky. LSST is going to be able to discover all these changing, fleeting objects like supernovae that Hitoshi talked about, but it’s a whole new phase of discovery. It’s inevitable we’re going to discover a whole load of new stuff that we’ve never even thought of.

H.M.: I’m sure there will be surprises!

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 Space.com.

Credit: NASA/JPL-Caltech

A Boeing CST-100 crew capsule approaches the International Space Station carrying a new crew for NASA in this artist’s illustration. NASA has awarded Being its first order for a commercial crew flight in 2017. Credit: Boeing

NASA has awarded Boeing with the first order for a commercial crew change flight to the International Space Station once the company’s new CST-100 space taxi is ready for manned flights in 2017.

Both Boeing and SpaceX are building private spaceships to ferry astronauts on round trips to the space station for NASA. While SpaceX has not received an order yet, NASA said the company will likely receive one later this year. Who flies first will be determined at a later date.

“Final development and certification are top priority for NASA and our commercial providers, but having an eye on the future is equally important to the commercial crew and station programs,” said Kathy Lueders, manager of NASA’s commercial crew program, in a statement. “Our strategy will result in safe, reliable and cost-effective crew missions.” [Boeing’s CST-100 Space Capsule in Pictures] 

The milestone follows on from Boeing successfully finishing the fourth stage in its Commercial Crew Transportation Capability (CCtCap) contract with NASA. Boeing showed the agency that its spacecraft design was ready for assembly, integration and testing.

“We’re on track to fly in 2017, and this critical milestone moves us another step closer in fully maturing the CST-100 design,” said John Mulholland, Boeing’s vice president of commercial programs, in a statement.

For its part, SpaceX successfully launched an unpiloted pad abort test earlier this month.

NASA makes its orders for CCtCap two or three years before the mission takes place, to give time for the companies to build the spacecraft. That said, Boeing (and SpaceX, when its mission is awarded) will need to fully finish its certification before being allowed to fly the astronauts.

Once the crew launches are running, a standard mission will see four crew members on board that are either from NASA or sponsored by NASA. The mission profile calls for the spacecraft to carry 220 pounds of pressurized cargo and to remain docked to the station for up to 210 days.

NASA added that the 2017 flight date depends on Congress awarding the agency’s full budget request for the 2016 fiscal year, and the ones following.

Follow Elizabeth Howell @howellspace, or Space.com @Spacedotcom. We’re also on Facebook and Google+. Original article on Space.com.

The Earth’s precession is captured in stunning detail in this image by a veteran astrophotographer.

In an email to Space.com, night sky photographer Miguel Claro said he developed a new photo technique  showing a Vega “polar” star trail. The image was taken from inside the Mourão Castle, in the Dark Sky Alqueva Reserve, the First Starlight Tourism Destination in the world, in Alentejo, Portugal.

Earth’s axis changes over time due to a phenomenon called “precession,” which pulls the direction of the axis in a circle that takes 26,000 years to trace out in the sky. What this means is the direction of north changes in the sky over time. A consequence of the precession is a changing pole star. Typically, Polaris is used to mark a position but Claro says he was fascinated with the possibility of using a different star. But because of Earth’s precession, the star Vega will likely serve as a new North Star in the year 14,000, even though it never comes closer than 5 degrees to the celestial pole, Claro wrote. [The Brightest Stars in the Night Sky]

 But what would that look like to future astrophotographers?

In a post on his website, Claro explains how he used two star-tracker mountings to help create the views of both Polaris and Vega serving as the North Star in the image above. He also posted a video of the skywatching feat on Vimeo.

Claro used a Canon EOS 6D – Canon EF 8-15 f/ 4L Fisheye USM at 8mm (All Sky) at exposure 30 seconds and ISO 2500 to create the images.

To see more amazing night sky photos submitted by Space.com readers, visit our astrophotography archive.

Editor’s note: If you have an amazing night sky photo you’d like to share for a possible story or image gallery, please contact managing editor Tariq Malik at spacephotos@space.com.

Follow Space.com on Twitter @Spacedotcom. We’re also on Facebook & Google+. Origina l article on Space.com.

Volunteers at Peterson Air Force Base take calls from children wanting to know where Santa is. Credit: U.S. Navy

North American Aerospace Defense Command (NORAD) is a military organization that is shared between the United States and Canada. The group is tasked with looking for threats or activity in aerospace, which can include anything from looking for aircraft, spacecraft or missiles. As of 2006, a renewal of the agreement added maritime activities.

The commander for NORAD is based at Peterson Air Force Base in Colorado and is expected to update both the U.S. president and the Canadian prime minister if required. NORAD’s work is also split between three regions: Alaska (at Elmendorf Air Force Base), Canada (Winnipeg, Manitoba) and continental (Tyndall Air Force Base in Florida).

In addition to its military work, NORAD is also known for tracking Santa every Christmas Eve. 

Early history

Around the same time that the United States and Russia were jockeying for positions in space, military concerns were changing the nature of defense back on Earth. When the Cold War began in the 1940s, Americans were concerned about the potential of long-range Soviet bombers, who may be able to cross an ocean without anyone in the United States knowing about it, according to NORAD.

The United States created an Air Defense Command in 1948, and in 1954 decided to add the Navy and Army to it as well. Dubbed Continental Air Defense Command (CONAD), the organization implemented an advance warning system including radar, and came up with the plans to deploy troops should an invasion occur.

Canada and the United States share a long border, so over time officials believed it made sense to share resources. This led to the creation of NORAD in 1958. Meanwhile, as the USSR improved its missile capabilities in the 1960s, NORAD took over an Air Force warning system to track the missiles worldwide by satellite.

“Throughout the 1970s, the ballistic missile threat caused policy makers to reassess the effectiveness of the air defense system,” NORAD wrote. 

“This meant the potential demise of the arguments for enhanced traditional air defense, and moved NORAD to focus on such challenges as improved warning of missile and space attack, defense against the ICBM [intercontinental ballistic missile], and greater protection and survival of command, control and communication networks and centers.”

Moving to modern days

Some structural changes came to NORAD in the late 1970s, such as changing the A to represent “Aerospace” rather than “Air” in its acronym. This was intended to represent its mandate to track satellites and space launches around the world.

Other structural changes included updating the early-warning system, and altering the command structure for ballistic missile warning and space surveillance.

NORAD also participated in campaigns such as tracking drug traffickers in the 1980s, after the Cold War finished. While its mandate to look for airborne threats continued, its work altered after the terrorist attacks of Sept. 11, 2001, in New York City. It now does regular air patrols under the name Operation Noble Eagle.

The organization has also had a few false alarms over the years. For example: on Nov. 9, 1979, according to History.com, NORAD officials received word that the Soviets were about to send missiles toward North America. 

After sending orders to interceptor aircraft and moving to protect the U.S. president, NORAD realized its mistake: a technician had accidentally loaded a training program for a Soviet attack. There were three unrelated computer problems for NORAD in the following year.

Tracking Santa

For the past six decades, NORAD has also taken on a special non-military role – it tracks down the whereabouts of the jolly old man in red.

It began Dec. 24, 1955, when the Continental Air Defense Command (CONAD) Operations Center in Colorado Springs, Colo., received a call from a young girl tracking down Santa Claus’ whereabouts. Several other calls followed, the result of a misprint in a local newspaper advertisement.

Colonel Harry Shoup, who was on duty, decided to take on the job and asked his colleagues to find where Santa was. CONAD continued the tradition every Christmas. When NORAD was created in 1958, the organization inherited the duty.

To this day, on Christmas Eve, NORAD provides updates on social media, on a website and through the telephone so children know Santa’s whereabouts.

Additional resources

A new view of Ceres, captured by NASA’s Dawn probe on May 23, 2015, shows fine details of the dwarf planet’s surface coming into focus. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

A new photo from NASA’s Dawn spacecraft shows the battered surface of the dwarf planet Ceres in unprecedented detail.

Dawn captured the image on May 23, when the probe was just 3,200 miles (5,100 kilometers) from Ceres. The photo’s resolution is about 1,600 feet (480 meters) per pixel, scientists said.

“The view shows numerous secondary craters, formed by the re-impact of debris strewn from larger impact sites. Smaller surface details like this are becoming visible with increasing clarity as Dawn spirals lower in its campaign to map Ceres,” NASA officials wrote in an image description today (May 28).

“The region shown here is located between 13 degrees and 51 degrees north latitude and 182 degrees and 228 degrees east longitude,” they added. “The image has been projected onto a globe of Ceres, which accounts for the small notch of black at upper right.”

NASA’s Dawn spacecraft captured this image of the dwarf planet Ceres’ heavily cratered surface on May 23, 2015, from a distance of 3,200 miles (5,100 kilometers).
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The $473 million Dawn mission launched in September 2007 to study Vesta and Ceres, the two largest objects in the main asteroid belt between Mars and Jupiter. Vesta and Ceres are planetary building blocks left over from the solar system’s early days, so Dawn’s observations should help researchers better understand how rocky worlds like Earth and Mars formed and grew, NASA officials have said.

Dawn orbited the 330-mile-wide (530 km) Vesta from July 2011 through September 2012 and reached Ceres, which is 590 miles (950 km) across, this March. In the process, Dawn became the first spacecraft to orbit two objects beyond the Earth-moon system, as well as the first to circle a dwarf planet.

Dawn is studying Ceres from a series of progressively closer-in orbits. The craft’s first science orbit lay about 8,400 miles (13,500 km) from the dwarf planet’s surface; Dawn is currently spiraling down to a 2,700-mile-high (4,400 km) orbit, which it should reach on June 3.

By the time Dawn wraps up its mission in June 2016, it will be eyeing Ceres’ intriguing surface from just 230 miles (375 km) away.

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

This “remastered” view of Europa is based on information from NASA’s Galileo mission of the 1990s. The 2014 view more closely resembles how the moon of Jupiter would look like to the human eye. Credit: NASA/JPL-Caltech/SETI Institute

NASA’s Europa spacecraft will use nine scientific instruments to assess the icy, ocean-harboring Jupiter moon’s ability to support life, space agency officials announced today (May 26).

The Europa probe — which is scheduled to launch in the early to mid-2020s — will carry supersharp cameras, a heat detector, ice-penetrating radar and a variety of other gear that will shed light on the satellite’s surface composition and the nature of its salty subsurface sea, among other things, NASA officials said.

The newly announced scientific payload “will help us take great strides forward in understanding the habitability of Europa,” Curt Niebur, Europa program scientist at NASA’s Washington headquarters, said during a news conference today. [Europa May Harbor Simple Life-Forms (Video)] 

Haven for life?

Astrobiologists regard the 1,900-mile-wide (3,100 kilometers) Europa as one of the solar system’s best bets to host extraterrestrial life.

Europa possesses a salty ocean beneath its ice shell, and this sea is apparently in contact with the moon’s rocky mantle, making possible a number of complex chemical reactions, scientists say. In addition, scientists think that Europa’s seafloor also features hydrothermal vents, providing a potential energy source for life-forms, if any exist in the dark depths. (Life thrives at Earth’s undersea vents, and some researchers think these environments gave rise to the planet’s first organisms.)

Most of what scientists know about Europa is based on data gathered by NASA’s Galileo mission, which orbited Jupiter in the 1990s and early 2000s and made about a dozen flybys of Europa during that time.

The new mission, which will cost roughly $2 billion, aims to build upon and increase that knowledge significantly, specifically investigating the icy world’s life-hosting potential. The current plan calls for sending a solar-powered spacecraft into orbit around Jupiter; from there, the probe would make about 45 flybys of Europa over the course of two and a half years or so.  

“We find that multiple flybys can allow us to get a complete picture of Europa,” said Jim Green, head of NASA’s Planetary Science division.

In July 2014, NASA asked researchers around the world to propose scientific instruments for the Europa mission. The space agency received 33 submissions and has now selected nine to go on the spacecraft, Niebur said today. [Europa and Its Ocean (Video)]

An artist’s illustration shows a concept for a future NASA mission to Europa, Jupiter’s moon.
Credit: NASA/JPL-Caltech

Taking Europa’s measure

The Europa flyby probe’s imaging system will consist of one wide-angle camera and one narrow-angle one, Niebur said. These two cameras will map almost 90 percent of Europa’s surface down to a resolution of 164 feet (50 meters), and will image parts of the moon 100 times more sharply than that.

Galileo, by contrast, imaged just 10 percent of Europa’s surface down to a resolution of 650 feet (200 m), Niebur said.

“If we’ve seen such amazing things on only 10 percent of the surface, it’s hard to even imagine the amazing things we’ll see when we look at the rest of Europa at even better resolution,” Niebur said.

Two other instruments — a magnetometer and a magnetic sounder — will work together to determine the thickness of Europa’s ice shell and the depth and salinity of its ocean. The ice-penetrating radar equipment will provide even more detail about the moon’s icy crust.

The probe will also carry a heat detector to pinpoint active sites on Europa — for example, places where plumes of water vapor may be erupting into space.

NASA’s Hubble Space Telescope spotted signs of such geysers erupting in 2012, but further searches have not yet confirmed their existence. The Europa spacecraft will carry a plume-hunting spectrograph, to both find and chacterize these elusive features.

Furthermore, an infrared spectrometer will allow the probe to map out the composition of Europa’s surface. Scientists are especially keen to know exactly what makes up the reddish-brown “gunk” that coats large fractures on the moon, since the stuff likely erupts onto the surface from the ocean below.

“If we can determine what that brown gunk is, we can then understand what is in the water — what is in the oceans of Europa — and that is an incredibly important question to answer if we’re trying to figure out if this place is habitable,” Niebur said.

The final two instruments — a mass spectrometer and a dust analyzer — will characterize gases and small solid particles that get blasted off Europa’s surface into space, allowing mission scientists to study the moon’s surface composition without touching down. 

No life-detection gear

The Europa flyby mission is dedicated to probing the moon’s habitability, not actively seeking out signs of life.

“Building a life detecor is incredibly difficult,” Niebur said. “We’re not even sure how to go about building it yet. But it’s something that has received renewed interest and vigor lately because of the Europa mission, so that’s something that we’re going to be poking into a lot more aggressively in the near future.”

Many astrobiologists would love to get a probe down on Europa’s surface — and, ideally, into the underground ocean. The data gathered by the flyby spacecraft could help pave the way for such an ambitious effort, NASA officials said.

“It’d be great to think that the results from this particular mission would lead, in the next decade, to some new and exciting concepts about potentially getting underneath the ice shell,” Green said.

More information is needed to determine if Europa “can be penetrated in a way to be able to get under the ice shell,” he added. “But that’s, indeed, in the distant future.”

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