Exoplanet-Hunting TESS Satellite to be Launched by SpaceX

A conceptual image of the Transiting Exoplanet Survey Satellite. Image Credit: MIT

The search for exoplanets is heating up, thanks to the deployment of space telescopes like Kepler and the development of new observation methods. In fact, over 1800 exoplanets have been discovered since the 1980s, with 850 discovered just last year. That’s quite the rate of progress, and Earth’s scientists have no intention of slowing down!

Hot on the heels of the Kepler mission and the ESA’s deployment of the Gaia space observatory last year, NASA is getting ready to launch TESS (the Transiting Exoplanet Survey Satellite). And to provide the launch services, NASA has turned to one of its favorite commercial space service providers – SpaceX.

The launch will take place in August 2017 from the Cape Canaveral Air Force Station in Florida, where it will be placed aboard a Falcon 9 v1.1 – a heavier version of the v 1.0 developed in 2013. Although NASA has contracted SpaceX to perform multiple cargo deliveries to the International Space Station, this will be only the second time that SpaceX has assisted the agency with the launch of a science satellite.

This past September, NASA also signed a lucrative contract with SpaceX worth $2.6 billion to fly astronauts and cargo to the International Space Station. As part of the Commercial Crew Program, SpaceX’s Falcon 9 and Dragon spacecraft were selected by NASA to help restore indigenous launch capability to the US.

James Webb Space Telescope. Image credit: NASA/JPL
Artist’s impression of the James Webb Space Telescope, the space observatory scheduled for launch in 2018. Image Credit: NASA/JPL

The total cost for TESS is estimated at approximately $87 million, which will include launch services, payload integration, and tracking and maintenance of the spacecraft throughout the course of its three year mission.

As for the mission itself, that has been the focus of attention for many years. Since it was deployed in 2009, the Kepler spacecraft has yielded more and more data on distant planets, many of which are Earth-like and potentially habitable. But in 2013, two of four reaction wheels on Kepler failed and the telescope has lost its ability to precisely point toward stars. Even though it is now doing a modified mission to hunt for exoplanets, NASA and exoplanet enthusiasts have been excited by the prospect of sending up another exoplanet hunter, one which is even more ideally suited to the task.

Once deployed, TESS will spend the next three years scanning the nearest and brightest stars in our galaxy, looking for possible signs of transiting exoplanets. This will involve scanning nearby stars for what is known as a “light curve”, a phenomenon where the visual brightness of a star drops slightly due to the passage of a planet between the star and its observer.

By measuring the rate at which the star dims, scientists are able to estimate the size of the planet passing in front of it. Combined with measurements the star’s radial velocity, they are also able to determine the density and physical structure of the planet. Though it has some drawbacks, such as the fact that stars rarely pass directly in front of their host stars, it remains the most effective means of observing exoplanets to date.

Number of extrasolar planet discoveries per year through September 2014, with colors indicating method of detection:   radial velocity   transit   timing   direct imaging   microlensing. Image Credit: Public domain
Number of extrasolar planet discoveries on up to Sept. 2014, with colors indicating method of detection. Blue: radial velocity; Green: transit; Yellow: timing, Red: direct imaging; Orange: microlensing. Image Credit: Alderon/Wikimedia Commons

In fact, as of 2014, this method became the most widely used for determining the presence of exoplanets beyond our Solar System. Compared to other methods – such as measuring a star’s radial velocity, direct imaging, the timing method, and microlensing – more planets have been detected using the transit method than all the other methods combined.

In addition to being able to spot planets by the comparatively simple method of measuring their light curve, the transit method also makes it possible to study the atmosphere of a transiting planet. Combined with the technique of measuring the parent star’s radial velocity, scientists are also able to measure a planet’s mass, density, and physical characteristics.

With TESS, it will be possible to study the mass, size, density and orbit of exoplanets. In the course of its three-year mission, TESS will be looking specifically for Earth-like and super-Earth candidates that exist within their parent star’s habitable zone.

This information will then be passed on to Earth-based telescopes and the James Webb Space Telescope – which will be launched in 2018 by NASA with assistance from the European and Canadian Space Agencies – for detailed characterization.

The TESS Mission is led by the Massachusetts Institute of Technology – who developed it with seed funding from Google – and is overseen by the Explorers Program at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Further Reading: NASA, SpaceX

 

Surprise! Galaxies Still Evolving in Present Universe

A giant spiral of gas dust and stars, Messier 101 spans 170,000 light-years and contains more than a trillion stars. Astronomers have uncovered a surprising trend in galaxy evolution where galaxies like M101 and the Milky Way Galaxy continued to develop into settled disk galaxies long after previously thought. Credit: NASA/ESA Hubble

Graceful in their turnings, spiral galaxies were thought to have reached their current state billions of years ago. A study of hundreds of galaxies, however, upsets that notion revealing that spiral galaxies, like the Andromeda Galaxy and our own Milky Way, have continued to change.

“Astronomers thought disk galaxies in the nearby universe had settled into their present form by about 8 billion years ago, with little additional development since,” said Susan Kassin, an astronomer at NASA’s Goddard Space Flight Center in Greenbelt, Md., and the study’s lead researcher in a press release. “The trend we’ve observed instead shows the opposite, that galaxies were steadily changing over this time period.”

A study of 544 star-forming galaxies observed by the Earth-based Keck and Hubble Space Telescope shows that disk galaxies like our Milky Way Galaxy unexpectedly reached their current state long after much of the universe’s star formation had ceased. Credit: NASA’s Goddard Space Flight Center

Astronomers used the twin 10-meter earth-bound W.M. Keck Observatory atop Hawaii’s Mauna Kea volcano and NASA’s Hubble Space Telescope to study 544 star-forming galaxies. Farther back in time, galaxies tend to be very different, say astronomers, with random and disorganized motions. Nearer to the present, star-forming galaxies look like well-ordered disk-shaped systems. Rotation in these galaxies trumps other internal, random motions. These galaxies are gradually settling into well-behaved disks with the most massive galaxies always showing higher organization.

This plot shows the fractions of settled disk galaxies in four time spans, each about 3 billion years long. There is a steady shift toward higher percentages of settled galaxies closer to the present time. At any given time, the most massive galaxies are the most settled. More distant and less massive galaxies on average exhibit more disorganized internal motions, with gas moving in multiple directions, and slower rotation speeds. Credit: NASA’s Goddard Space Flight Center

The sampling of galaxies studied, from the Deep Extragalactic Evolutionary Probe 2 (DEEP2) Redshift Survey, ranged between 2 billion and 8 billion light-years from Earth with masses between 0.3 percent to 100 percent that of our own Milky Way Galaxy. Researchers looked at all galaxies in this time range with emission lines bright enough to determine internal motions. Researchers focused on emission lines characteristically emitted by gas within the galaxy. The emission lines not only tell scientists about the elements that make up the galaxies but also red shifting of emission lines contains information on the internal motions and distance.

“Previous studies removed galaxies that did not look like the well-ordered rotating disks now common in the universe today,” said co-author Benjamin Weiner, an astronomer at the University of Arizona in Tucson. “By neglecting them, these studies examined only those rare galaxies in the distant universe that are well-behaved and concluded that galaxies didn’t change.”

In the past 8 billion years, mergers between galaxies, both large and small, has decreased. So has the overall rate of star formation and associated disruptions due to supernovae explosions. Both factors may play a role in the newly found trend, say scientists.

The Milky Way Galaxy may have gone through the same chaotic growing and changing as the galaxies in the DEEP2 sample before settling into its present state at just about the same time the Sun and Earth were forming, say team scientists. By observing the pattern, astronomers can now adjust computer simulations of galaxy evolution until they replicate the observations. Then the hunt will be on to determine the physical processes responsible for the trend.

This cosmological simulation follows the development of a single disk galaxy throughout the life of the Universe; about 13.5 billion years. Red colors show old stars, young stars show as white and bright blue while the distribution of gas shows as a pale blue. The computer-generated view spans about 300,000 light-years. The simulation, running on the Pleiades supercomputer at NASA’s Ames Research Center in Moffett Field, California, took about 1 million CPU hours to complete. Credit: F. Governato and T. Quinn (Univ. of Washington), A. Brooks (Univ. of Wisconsin, Madison), and J. Wadsley (McMaster Univ.).

A paper detailing the findings will be published in the October 20, 2012 The Astrophysical Journal.

Source: NASA

Our Gorgeous, Graceful, Gradient Sun

Here’s a mesmerizing video from the folks over at NASA’s Goddard Space Flight Center’s visualization studio showing the Sun in a whole new light… well, a reprocessed light anyway.

Using what’s called a gradient filter, images of the Sun can be adjusted to highlight the intricate details of its dynamic atmosphere. Magnetic activity that’s invisible to human vision can be brought into view, showing the powerful forces in play within the Sun’s corona and helping researchers better understand how it affects space weather. (Plus they sure are pretty!)

Compiled into a video, these images reveal the hidden beauty — and power — of our home star in action.

Video courtesy NASA/GSFC

The Zen of the Sun

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Images and video from the Solar Dynamics Observatory have shown us that the fury of the Sun can be mesmerizingly beautiful. SDO has allowed us to see loops of plasma in various wavelengths, coils of magnetic fields that are invisible to human eyes, and so much more. And then, sometimes, happy accidents happen, creating beautiful images just for beauty’s sake. The teams at Goddard Space Flight Center’s Multimedia Center are wizards at honing SDO’s raw data into works of art, and video producer Scott Wiessinger sent a note today to say he accidentally happened across a “really neat Photoshop effect,” that while not really useful scientifically, is rather beautiful and fun to watch. “There isn’t any science behind this video, it’s just a nice ‘moment of zen,’” he said.

The video is below.

The lead image shows one of the original frames in the 171 Angstrom wavelength of extreme ultraviolet, with the additional processing. This wavelength shows plasma in the corona that is around 600,000 Kelvin. The loops represent plasma held in place by magnetic fields. They are concentrated in “active regions” where the magnetic fields are the strongest. These active regions usually appear in visible light as sunspots.

So, enjoy a little contemplative moment courtesy of the Goddard team:

The video shows about 24 hours of activity on September 25, 2011.

Thanks to Scott and the Goddard team for sharing their work! See more images with this unique processing at their website.

Go On a Grand Tour of the Moon


To honor the Lunar Reconnaissance Orbiter’s amazing 1,000 days in science-filled orbit, the LRO team at Goddard Space Flight Center has created a wonderful video tour of the lunar surface like you’ve never seen it before!

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“Tour of the Moon” takes viewers to several breathtaking locations on the Moon, including Orientale Basin, Shackleton crater, Tycho crater, Aristarchus Plateau, Mare Serenitatis, Compton-Belkovich volcano, Tsiolkovsky crater and more. The fully narrated video is above, and clips from each of the stops on the tour are available in many other formats here.

In addition, another video highlighting the dramatic evolution of the Moon was released today… you can view the full narrated version in 2D and stereoscopic 3D here.

iPad owners can also download the NASA Viz app to see this and other NASA stories, updated twice a week.

Credit: NASA Goddard Space Flight Center

Tropical Storm Lee Drenches Gulf Coast as Hurricane Katia Aims for US East Coast

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New imagery from NASA and NOAA satellites taken today (Sept 4) shows the extent of a hurricane season storm currently ravaging the US Gulf Coast and another potentially posing a new threat to US East Coast areas still suffering from the vast destruction caused by Hurricane Irene just days ago. Data from the NASA and NOAA satellites is critical in providing advance warning to government officials and local communities to save human lives and minimize property damage. .

Slow moving Tropical Storm Lee has unleashed strong thunderstorms and heavy rainfall in several Gulf Coast states. Rainfall amounts of up to 7 to 14 inches over the last 48 hours are currently drenching coastal and inland communities – especially in Louisiana, Mississippi and Alabama along a wide swath that extends from Texas to the Florida panhandle.

Isolated pockets of Gulf State areas may see up to 20 inches of rainfall. Severe flooding to homes and roads has occurred in some locations. Winds have diminished from 60 mph on Saturday (Sept. 3) to 45 mph on Sunday.

Imagery and measurements from the Aqua and GOES-13 satellites from NASA and NOAA revealed that TS Lee finally made landfall in Louisiana after two days of drenching rain along the Gulf Coast..

A tropical storm warning is in effect on Sept 4 for New Orleans, Lake Pontchartrain, and Lake Maurepas. Fortunately the rebuilt levees in New Orleans appear to holding in the first serious test since the vast destruction of Hurricane Katrina. Other areas are less lucky.

This infrared image of Tropical Storm Lee on Sept. 3 at 3:47 p.m. EDT when the center was still sitting south of the Louisiana coast. The strongest thunderstorms and coldest clouds (purple) stretched from Mobile Bay, south into the Gulf of Mexico and covered about 1/3rd of the Gulf of Mexico. Winds were 55 mph at the time of this image. The image was taken by the AIRS instrument on NASA's Aqua satellite. Credit: NASA JPL, Ed Olsen NASA

Lee’s tropical force winds now extend out 275 miles from the center. A large part of Lee is still over the Gulf of Mexico where the driving wind and rain affected operations on some oil rigs.

Lee has spawned more than a dozen tornadoes in the Gulf Coast states. The storm is spreading more heavy rain and winds on a northeast to east- northeast heading tracking towards Tennessee over the next 24 to 36 hours according to the latest weather forecasts.

Meanwhile Hurricane Katia is packing winds of 110 MPH and is on a path that could cause it to make landfall on the Outer Banks of North Carolina just a week after the state suffered from Hurricane Irene.

Hurricane Katia has the potential to affect the launch of NASA’s GRAIL Lunar Mappers slated for liftoff on Sept. 8 from Cape Canaveral, Florida, depending on its exact course.

This GOES-13 satellite image shows Hurricane Katia (right), Tropical Depression 13 (left) and System 94L (top). Credit: NASA/NOAA GOES Project

Irene caused extensive flooding and devastation on the hundred year scale in several US states still reeling from flooding and destruction. More than 43 deaths have been reported so far, including emergency rescue workers. Initial damage estimates are over $6 Billion.

Thousands of East Coast homes and businesses are still without power as strong after effects from Irene continue to play out.

President Obama toured flood stricken areas of Paterson, New Jersey today (Sept. 4).

According to a statement by Rob Gutro, of NASA’s Goddard Space Flight Center, Greenbelt, Md; Tropical Storm Lee’s winds had dropped from 60 mph exactly 24 hours before to 45 mph at 8 a.m. EDT on Sept. 4.

Lee’s center was over Vermillion Bay, Louisiana near 29.7 North and 92.0 West. It was crawling to the northeast near 3 mph (6 kmh) and expected to continue in that direction today, turning to the east-northeast tonight. Because Lee’s center is over land, he is expected to continue weakening gradually in the next couple of days. Lee’s outer bands still extend far over the Gulf of Mexico, bringing in more moisture and keeping the system going.

Here's a 3-D look at Tropical Depression 13 from NASA's TRMM Satellite on Sept 1. Some of the highest thunderstorm towers in that area were shown by PR data to reach heights of over 15km (~9.3 miles) and there were areas of heavy rain - which is going to affect the shoreline.. waves of rainfall to move inland. Credit: NASA/Goddard
This visible image of Tropical Storm Lee was taken from the GOES-13 satellite on Saturday, Sept. 3 at 9:32 a.m. EDT. It shows the extent of Lee's cloud cover over Louisiana, Mississippi, Alabama and the Florida Panhandle. The clearing on the southeastern side is a result of drier air moving in and preventing development of thunderstorms. Credit: NASA/NOAA GOES Project

How Did Jupiter Shape Our Solar System?

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Jupiter hasn’t always been in the same place in our solar system. Early in the history of our solar system, Jupiter moved inward towards the sun, almost to where Mars currently orbits now, and then back out to its current position.

The migration through our solar system of Jupiter had some major effects on our solar system. Some of the effects of Jupiter’s wanderings include effects on the asteroid belt and the stunted growth of Mars.

What other effects did Jupiter’s migration have on the early solar system and how did scientists make this discovery?

In a research paper published in the July 14th issue of Nature, First author Kevin Walsh and his team created a model of the early solar system which helps explain Jupiter’s migration. The team’s model shows that Jupiter formed at a distance of around 3.5 A.U (Jupiter is currently just over 5 A.U from the sun) and was pulled inward by currents in the gas clouds that still surrounded the sun at the time. Over time, Jupiter moved inward slowly, nearly reaching the same distance from the sun as the current orbit of Mars, which hadn’t formed yet.

“We theorize that Jupiter stopped migrating toward the sun because of Saturn,” said Avi Mandell, one of the paper’s co-authors. The team’s data showed that Jupiter and Saturn both migrated inward and then outward. In the case of Jupiter, the gas giant settled into its current orbit at just over 5 a.u. Saturn ended its initial outward movement at around 7 A.U, but later moved even further to its current position around 9.5 A.U.

Astronomers have had long-standing questions regarding the mixed composition of the asteroid belt, which includes rocky and icy bodies. One other puzzle of our solar system’s evolution is what caused Mars to not develop to a size comparable to Earth or Venus.

Artist's conception of early planetary formation from gas and dust around a young star. Image Credit: NASA/JPL-Caltech

Regarding the asteroid belt, Mandell explained, “Jupiter’s migration process was slow, so when it neared the asteroid belt, it was not a violent collision but more of a do-si-do, with Jupiter deflecting the objects and essentially switching places with the asteroid belt.”

Jupiter’s slow movement caused more of a gentle “nudging” of the asteroid belt when it passed through on its inward movement. When Jupiter moved back outward, the planet moved past the location it originally formed. One side-effect of caused by Jupiter moving further out from its original formation area is that it entered the region of our early solar system where icy objects were. Jupiter pushed many of the icy objects inward towards the sun, causing them to end up in the asteroid belt.

“With the Grand Tack model, we actually set out to explain the formation of a small Mars, and in doing so, we had to account for the asteroid belt,” said Walsh. “To our surprise, the model’s explanation of the asteroid belt became one of the nicest results and helps us understand that region better than we did before.”

With regards to Mars, in theory Mars should have had a larger supply gas and dust, having formed further from the sun than Earth. If the model Walsh and his team developed is correct, Jupiter foray into the inner solar system would have scattered the material around 1.5 A.U.

Mandell added, “Why Mars is so small has been the unsolvable problem in the formation of our solar system. It was the team’s initial motivation for developing a new model of the formation of the solar system.”

An interesting scenario unfolds with Jupiter scattering material between 1 and 1.5 AU. Instead of the higher concentration of planet-building materials being further out, the high concentration led to Earth and Venus forming in a material-rich region.

The model Walsh and his team developed brings new insight into the relationship between the inner planets, our asteroid belt and Jupiter. The knowledge learned not only will allow scientists to better understand our solar system, but helps explain the formation of planets in other star systems. Walsh also mentioned, “Knowing that our own planets moved around a lot in the past makes our solar system much more like our neighbors than we previously thought. We’re not an outlier anymore.”

If you’d like to access the paper (subscription or paid/university access required), you can do so at: http://www.nature.com/nature/journal/v475/n7355/full/nature10201.html

Source: NASA Solar System News, Nature

JWST Built with ‘Unobtainium’

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The James Webb Space Telescope (JWST) is the much anticipated, long awaited “next generation” telescope, which we hope will look further back in time, and deeper within dusty star forming regions, using longer wavelengths and more sensitivity than any previous space telescope. In order to take us to this next level, you’d kinda figure that new technologies would have to be developed in order for this ground-breaking, super-huge telescope to be built. You’d be right.

In fact, engineers had to use a little unobtainium to build the one-of-a-kind chassis, the backbone that will hold the spacecraft together.

Unobtainium isn’t just the name of the material mined in James Cameron’s movie “Avatar.” It is a word used in engineering — and sometimes fiction – to describe any extremely rare, costly, or physically impossible material or device needed to fulfill a given design for a given application.

The chassis for JWST – called the the Integrated Science Instrument Module ISIM – is made of a never-before-manufactured composite material which had to withstand the super-cold temperatures it will encounter when the observatory reaches its orbit 1.5-million kilometers (930,000 miles) from Earth.

The ISIM just passed an extremely important test, surviving temperatures that plunged as low as 27 Kelvin (-411 degrees Fahrenheit), colder than the surface of Pluto during a cycle of testing in Goddard’s Space Environment Simulator — a three-story thermal-vacuum chamber that simulates the temperature and vacuum conditions found in space.

The team at Goddard Space Flight Center who were charged with building the chassis needed a material that would assure the various instruments on JWST would maintain a precise cryogenic alignment and stability, yet survive the extreme gravitational forces experienced during launch.

The test was done to find out whether the car-sized structure contracted and distorted as predicted when it cooled from room temperature to the frigid — very important since the science instruments must maintain a specific location on the structure to receive light gathered by the telescope’s 6.5-meter (21.3-feet) primary mirror. If the structure shrunk or distorted in an unpredictable way due to the cold, the instruments no longer would be in position to gather data about everything from the first luminous glows following the Big Bang to the formation of star systems capable of supporting life.

When they first began, there was nothing out there that remotely fit the description of what was needed. So, that left one alternative: developing their own as-yet-to-be manufactured material, which team members jokingly referred to as “unobtainium.” Through mathematical modeling, the team discovered that by combining two composite materials, it could create a carbon fiber/cyanate-ester resin system that would be ideal for fabricating the structure’s square tubes that measure 75-mm (3-inch) in diameter.

During the recent 26-day test, and with repeated cycles of testing, the truss-like assembly designed by Goddard engineers did not crack. The structure shrunk as predicted by only 170 microns — the width of a needle —when it reached 27 Kelvin (-411 degrees Fahrenheit), far exceeding the design requirement of about 500 microns. “We certainly wouldn’t have been able to realign the instruments on orbit if the structure moved too much,” said ISIM Structure Project Manager Eric Johnson. “That’s why we needed to make sure we had designed the right structure.”

This type of structure could serve NASA in the future for the next-generation beyond JWST, and could also be a “spinoff” that manufacturers could find useful in designing structures that demand a high tolerance in conditions.

Source: NASA Goddard