A Day In Our Lives With X-Ray Tech

Are you scared about going up into space?

I’m not scared, but I have a healthy amount of nervousness because I don’t know exactly what to expect. I have a lot of great advice, but you don’t know until you actually get there.

10 Steps to Confirm a Planet Around Another Star

So you think you found an exoplanet -- a planet around another star? It’s not as simple as pointing a telescope to the sky and looking for a planet that waves back. Scientists gather many observations and carefully analyze their data before they can be even somewhat sure that they’ve discovered new worlds.

Here are 10 things to know about finding and confirming exoplanets.

This is an illustration of the different elements in our exoplanet program, including ground-based observatories, like the W. M. Keck Observatory, and space-based observatories like Hubble, Spitzer, Kepler, TESS, James Webb Space Telescope, WFIRST and future missions.

1. Pick your tool to take a look.

The vast majority of planets around other stars have been found through the transit method so far. This technique involves monitoring the amount of light that a star gives off over time, and looking for dips in brightness that may indicate an orbiting planet passing in front of the star.

We have two specialized exoplanet-hunting telescopes scanning the sky for new planets right now -- Kepler and the Transiting Exoplanet Survey Satellite (TESS) -- and they both work this way. Other methods of finding exoplanets include radial velocity (looking for a “wobble” in a star's position caused by a planet’s gravity), direct imaging (blocking the light of the star to see the planet) and microlensing (watching for events where a star passes in front of another star, and the gravity of the first star acts as a lens).

Here’s more about finding exoplanets.

2. Get the data.

To find a planet, scientists need to get data from telescopes, whether those telescopes are in space or on the ground. But telescopes don’t capture photos of planets with nametags. Instead, telescopes designed for the transit method show us how brightly thousands of stars are shining over time. TESS, which launched in April and just began collecting science data, beams its stellar observations back to Earth through our Deep Space Network, and then scientists get to work.

3. Scan the data for planets.

Researchers combing through TESS data are looking for those transit events that could indicate planets around other stars. If the star’s light lessens by the same amount on a regular basis -- for example, every 10 days -- this may indicate a planet with an orbital period (or “year”) of 10 days. The standard requirement for planet candidates from TESS is at least two transits -- that is, two equal dips in brightness from the same star.

4. Make sure the planet signature couldn’t be something else.

Not all dips in a star's brightness are caused by transiting planets. There may be another object -- such as a companion star, a group of asteroids, a cloud of dust or a failed star called a brown dwarf, that makes a regular trip around the target star. There could also be something funky going on with the telescope’s behavior, how it delivered the data, or other “artifacts” in data that just aren’t planets. Scientists must rule out all non-planet options to the best of their ability before moving forward.

5. Follow up with a second detection method.

Finding the same planet candidate using two different techniques is a strong sign that the planet exists, and is the standard for “confirming” a planet. That’s why a vast network of ground-based telescopes will be looking for the same planet candidates that TESS discovers. It is also possible that TESS will spot a planet candidate already detected by another telescope in the past. With these combined observations, the planet could then be confirmed. The first planet TESS discovered, Pi Mensae c, orbits a star previously observed with the radial-velocity method on the ground. Scientists compared the TESS data and the radial-velocity data from that star to confirm the presence of planet “c.”

Scientists using the radial-velocity detection method see a star’s wobble caused by a planet’s gravity, and can rule out other kinds of objects such as companion stars. Radial-velocity detection also allows scientists to calculate the mass of the planet.

6. …or at least another telescope.

Other space telescopes may also be used to help confirm exoplanets, characterize them and even discover additional planets around the same stars. If the planet is detected by the same method, but by two different telescopes, and has received enough scrutiny that the scientists are more than 99 percent sure it’s a planet, it is said to be “validated” instead of “confirmed.”

7. Write a paper.

After thoroughly analyzing the data, and running tests to make sure that their result still looks like the signature of a planet, scientists write a formal paper describing their findings. Using the transit method, they can also report the size of the planet. The planet’s radius is related to how much light it blocks from the star, as well as the size of the star itself. The scientists then submit the study to a journal.

8. Wait for peer review.

Scientific journals have a rigorous peer review process. This means scientific experts not involved in the study review it and make sure the findings look sound. The peer-reviewers may have questions or suggestions for the scientists. When everyone agrees on a version of the study, it gets published.

9. Publish the study.

When the study is published, scientists can officially say they have found a new planet. This may still not be the end of the story, however. For example, the TRAPPIST telescope in Chile first thought they had discovered three Earth-size planets in the TRAPPIST-1 system. When our Spitzer Space Telescope and other ground-based telescopes followed up, they found that one of the original reported planets (the original TRAPPIST-1d) did not exist, but they discovered five others --bringing the total up to seven wondrous rocky worlds.

10. Catalog and celebrate -- and look closer if you can!

Confirmed planets get added to our official catalog. So far, Kepler has sent back the biggest bounty of confirmed exoplanets of any telescope -- more than 2,600 to date. TESS, which just began its planet search, is expected to discover many thousands more. Ground-based follow-up will help determine if these planets are gaseous or rocky, and possibly more about their atmospheres. The forthcoming James Webb Space Telescope will be able to take a deeper look at the atmospheres of the most interesting TESS discoveries.

Scientists sometimes even uncover planets with the help of people like you: exoplanet K2-138 was discovered through citizen scientists in Kepler’s K2 mission data. Based on surveys so far, scientists calculate that almost every star in the Milky Way should have at least one planet. That makes billions more, waiting to be found! Stay up to date with our latest discoveries using this exoplanet counter.

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Meet Megan McArthur, NASA Astronaut & Crew-2 Pilot

NASA astronaut Megan McArthur will launch on Friday, April 23 to the International Space Station as the pilot for NASA’s SpaceX Crew-2 mission! This is the second crew rotation flight with astronauts on the Crew Dragon spacecraft and the first launch with two international partners as part of the agency’s Commercial Crew Program. McArthur is responsible for spacecraft systems and performance and is assigned to be a long-duration space station crew member. While this is her first trip to the space station, McArthur’s career has prepared her well for this important role on the Crew-2 team!

McArthur on the Crew Access Arm of the mobile launcher inside the Vehicle Assembly Building at Kennedy Space Center. Credits: NASA/Joel Kowsky

McArthur was born in Honolulu, Hawaii and grew up in California. She is a former Girl Scout and has a Bachelor of Science in Aerospace Engineering from the University of California, Los Angeles and a Ph.D. in Oceanography from the University of California, San Diego where she performed research activities at the Scripps Institution of Oceanography.

McArthur floating in microgravity during her STS-125 mission in 2009 aboard space shuttle Atlantis. Credits: NASA

While in graduate school, McArthur conducted research, served as Chief Scientist for at-sea data collection operations, and planned and led diving operations. She also volunteered at the Birch Aquarium at Scripps, conducting educational demonstrations for the public from inside a 70,000-gallon exhibit tank of the California Kelp Forest. Her experience conducting research in extreme conditions will certainly come in handy once she’s aboard the space station, as a big part of the astronauts’ job involves running research experiments in microgravity.

McArthur, seen through the window of space shuttle Atlantis, operating the robotic arm during a spacewalk. Credits: NASA

McArthur was selected as a NASA astronaut in 2000 and flew her first spaceflight aboard STS-125, the final space shuttle mission to service the Hubble Space Telescope. She worked as the flight engineer during launch and landing, and also served as the shuttle's robotic arm operator as she carefully retrieved the telescope and placed it in the shuttle’s cargo bay for servicing. The successful mission improved the telescope's capabilities and extended its life – and Hubble is still helping us make discoveries about our universe.

McArthur pictured in her pressure suit during a training session at SpaceX HQ in Hawthorne, California. Credits: NASA

Now, it’s time for the next big milestone in McArthur’s career! On Friday, April 23 Crew-2 will launch from Kennedy Space Center in Florida en route to the International Space Station. McArthur is the pilot of the Crew Dragon spacecraft and second-in-command for the mission.

NASA TV coverage of Crew-2 launch preparations and liftoff will begin at 1:30 a.m. EDT Friday, April 23 with launch scheduled for 5:49 a.m. EDT. Crew Dragon is scheduled to dock to the space station Saturday, April 24, at approximately 5:10 a.m. EDT. Watch live: www.nasa.gov/nasalive

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Studying Sediments in Space

An International Space Station investigation called BCAT-CS studies dynamic forces between sediment particles that cluster together.

For the study, scientists sent mixtures of quartz and clay particles to the space station and subjected them to various levels of simulated gravity.

Conducting the experiment in microgravity makes it possible to separate out different forces that act on sediments and look at the function of each.

Sediment systems of quartz and clay occur many places on Earth, including rivers, lakes, and oceans, and affect many activities, from deep-sea hydrocarbon drilling to carbon sequestration.

Understanding how sediments behave has a range of applications on Earth, including predicting and mitigating erosion, improving water treatment, modeling the carbon cycle, sequestering contaminants and more accurately finding deep sea oil reservoirs.

It also may provide insight for future studies of the geology of new and unexplored planets.

Follow @ISS_RESEARCH to learn more.

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Five Ways the International Space Station’s National Lab Enables Commercial Research

A growing number of commercial partners use the International Space Station National Lab. With that growth, we will see more discoveries in fundamental and applied research that could improve life on the ground.

Space Station astronaut Kate Rubins was the first person to sequence DNA in microgravity.

Since 2011, when we engaged the Center for the Advancement of Science in Space (CASIS) to manage the International Space Station (ISS) National Lab, CASIS has partnered with academic researchers, other government organizations, startups and major commercial companies to take advantage of the unique microgravity lab. Today, more than 50 percent of CASIS’ experiments on the station represent commercial research.

Here’s a look at five ways the ISS National Lab is enabling new opportunities for commercial research in space.

1. Supporting Commercial Life Sciences Research

One of the main areas of focus for us in the early origins of the space station program was life sciences, and it is still a major priority today. Studying the effects of microgravity on astronauts provides insight into human physiology, and how it evolves or erodes in space. CASIS took this knowledge and began robust outreach to the pharmaceutical community, which could now take advantage of the microgravity environment on the ISS National Lab to develop and enhance therapies for patients on Earth. Companies such as Merck, Eli Lilly & Company, and Novartis have sent several experiments to the station, including investigations aimed at studying diseases such as osteoporosis, and examining ways to enhance drug tablets for increased potency to help patients on Earth. These companies are trailblazers for many other life science companies that are looking at how the ISS National Lab can advance their research efforts.

2. Enabling Commercial Investigations in Material and Physical Sciences

Over the past few years, CASIS and the ISS National Lab also have seen a major push toward material and physical sciences research by companies interested in enhancing their products for consumers. Examples range from Proctor and Gamble’s investigation aimed at increasing the longevity of daily household products, to Milliken’s flame-retardant textile investigation to improve protective clothing for individuals in harm’s way, and companies looking to enhance materials for household appliances. Additionally, CASIS has been working with a variety of companies to improve remote sensing capabilities in order to better monitor our oceans, predict harmful algal blooms, and ultimately, to better understand our planet from a vantage point roughly 250 miles above Earth.

3. Supporting Startup Companies Interested in Microgravity Research 

CASIS has funded a variety of investigations with small startup companies (in particular through seed funding and grant funding from partnerships and funded solicitations) to leverage the ISS National Lab for both research and test-validation model experiments. CASIS and The Boeing Company recently partnered with MassChallenge, the largest startup accelerator in the world, to fund three startup companies to conduct microgravity research.

4. Enabling Validation of Low-Earth Orbit Business Models 

The ISS National Lab helps validate low-Earth orbit business models. Companies such as NanoRacks, Space Tango, Made In Space, Techshot, and Controlled Dynamics either have been funded by CASIS or have sent instruments to the ISS National Lab that the research community can use, and that open new channels for inquiry. This has allowed the companies that operate these facilities to validate their business models, while also building for the future beyond station.

5. Demonstrating the Commercial Value of Space-based Research

We have been a key partner in working with CASIS to demonstrate to American businesses the value of conducting research in space. Through outreach events such as our Destination Station, where representatives from the International Space Station Program Science Office and CASIS select cities with several major companies and meet with the companies to discuss how they could benefit from space-based research. Over the past few years, this outreach has proven to be a terrific example of building awareness on the benefits of microgravity research.

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Unveiling the Center of Our Milky Way Galaxy

We captured an extremely crisp infrared image of the center of our Milky Way galaxy. Spanning more than 600 light-years, this panorama reveals details within the dense swirls of gas and dust in high resolution, opening the door to future research into how massive stars are forming and what’s feeding the supermassive black hole at our galaxy’s core.

Among the features coming into focus are the jutting curves of the Arches Cluster containing the densest concentration of stars in our galaxy, as well as the Quintuplet Cluster with stars a million times brighter than our Sun. Our galaxy’s black hole takes shape with a glimpse of the fiery-looking ring of gas surrounding it.

The new view was made by the world’s largest airborne telescope, the Stratospheric Observatory for Infrared Astronomy, or SOFIA.

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Spilling the Sun’s Secrets

You might think you know the Sun: It looks quiet and unchanging. But the Sun has secrets that scientists have been trying to figure out for decades.  

One of our new missions — Parker Solar Probe — is aiming to spill the Sun’s secrets and shed new light on our neighbor in the sky.

Even though it’s 93 million miles away, the Sun is our nearest and best laboratory for understanding the inner workings of stars everywhere. We’ve been spying on the Sun with a fleet of satellites for decades, but we’ve never gotten a close-up of our nearest star.

This summer, Parker Solar Probe is launching into an orbit that will take it far closer to the Sun than any instrument has ever gone. It will fly close enough to touch the Sun, sweeping through the outer atmosphere — the corona — 4 million miles above the surface.

This unique viewpoint will do a lot more than provide gossip on the Sun. Scientists will take measurements to help us understand the Sun’s secrets — including those that can affect Earth.

Parker Solar Probe is equipped with four suites of instruments that will take detailed measurements from within the Sun's corona, all protected by a special heat shield to keep them safe and cool in the Sun's ferocious heat.

The corona itself is home to one of the Sun’s biggest secrets: The corona's mysteriously high temperatures. The corona, a region of the Sun’s outer atmosphere, is hundreds of times hotter than the surface below. That's counterintuitive, like if you got warmer the farther you walked from a campfire, but scientists don’t yet know why that's the case.

Some think the excess heat is delivered by electromagnetic waves called Alfvén waves moving outwards from the Sun’s surface. Others think it might be due to nanoflares — bomb-like explosions that occur on the Sun’s surface, similar to the flares we can see with telescopes from Earth, but smaller and much more frequent. Either way, Parker Solar Probe's measurements direct from this region itself should help us pin down what's really going on.

We also want to find out what exactly accelerates the solar wind — the Sun's constant outpouring of material that rushes out at a million miles per hour and fills the Solar System far past the orbit of Pluto. The solar wind can cause space weather when it reaches Earth — triggering things like the aurora, satellite problems, and even, in rare cases, power outages.

We know where the solar wind comes from, and that it gains its speed somewhere in the corona, but the exact mechanism of that acceleration is a mystery. By sampling particles directly at the scene of the crime, scientists hope Parker Solar Probe can help crack this case.

Parker Solar Probe should also help us uncover the secrets of some of the fastest particles from the Sun. Solar energetic particles can reach speeds of more than 50% the speed of light, and they can interfere with satellites with little warning because of how fast they move. We don't know how they get so fast — but it's another mystery that should be solved with Parker Solar Probe on the case.  

Parker Solar Probe launches summer 2018 on a seven-year mission to touch the Sun. Keep up with the latest on the Sun at @NASASun on Twitter, and follow along with Parker Solar Probe's last steps to launch at nasa.gov/solarprobe.

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Jessica, first of all, I love you. Second, what's it like being a part of the first class that was 50% female?

Thank you!  The best part is that I think the fact that our class is 50% female simply reflects how far our society has come, and that is a great thing!  To us, there really is no difference on whether or not we are female or male, what backgrounds we come from, etc., we are one team, one family, all contributing to the same cause (which is an extraordinary feeling!).  I’m definitely very proud and honored to be part of the 21st astronaut class.

A View into the Past

Our Hubble Space Telescope just found the farthest individual star ever seen to date!

Nicknamed “Earendel” (“morning star” in Old English), this star existed within the first billion years after the universe’s birth in the big bang. Earendel is so far away from Earth that its light has taken 12.9 billion years to reach us, far eclipsing the previous single-star record holder whose light took 9 billion years to reach us.

Though Earendel is at least 50 times the mass of our Sun and millions of times as bright, we’d normally be unable to see it from Earth. However, the mass of a huge galaxy cluster between us and Earendel has created a powerful natural magnifying glass. Astronomers expect that the star will be highly magnified for years.

Earendel will be observed by NASA’s James Webb Space Telescope. Webb's high sensitivity to infrared light is needed to learn more about this star, because its light is stretched to longer infrared wavelengths due to the universe's expansion.

How Do We Learn About a Planet’s Atmosphere?

The first confirmation of a planet orbiting a star outside our solar system happened in 1995. We now know that these worlds – also known as exoplanets – are abundant. So far, we’ve confirmed more than 4000. Even though these planets are far, far away, we can still study them using ground-based and space-based telescopes.

Our upcoming James Webb Space Telescope will study the atmospheres of the worlds in our solar system and those of exoplanets far beyond. Could any of these places support life? What Webb finds out about the chemical elements in these exoplanet atmospheres might help us learn the answer.

How do we know what’s in the atmosphere of an exoplanet?

Most known exoplanets have been discovered because they partially block the light of their suns. This celestial photo-bombing is called a transit.

During a transit, some of the star's light travels through the planet's atmosphere and gets absorbed.

The light that survives carries information about the planet across light-years of space, where it reaches our telescopes.

(However, the planet is VERY small relative to the star, and VERY far away, so it is still very difficult to detect, which is why we need a BIG telescope to be sure to capture this tiny bit of light.)

So how do we use a telescope to read light?

Stars emit light at many wavelengths. Like a prism making a rainbow, we can separate light into its separate wavelengths. This is called a spectrum. Learn more about how telescopes break down light here. 

Visible light appears to our eyes as the colors of the rainbow, but beyond visible light there are many wavelengths we cannot see.

Now back to the transiting planet...

As light is traveling through the planet's atmosphere, some wavelengths get absorbed.

Which wavelengths get absorbed depends on which molecules are in the planet's atmosphere. For example, carbon monoxide molecules will capture different wavelengths than water vapor molecules.

So, when we look at that planet in front of the star, some of the wavelengths of the starlight will be missing, depending on which molecules are in the atmosphere of the planet.

Learning about the atmospheres of other worlds is how we identify those that could potentially support life...

...bringing us another step closer to answering one of humanity's oldest questions: Are we alone?

Watch the full video where this method of hunting for distant planets is explained:

To learn more about NASA’s James Webb Space Telescope, visit the website, or follow the mission on Facebook, Twitter and Instagram. 

Text and graphics credit Space Telescope Science Institute

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