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A budding star spits out jets of superheated gas and dust in the Carina Nebula. Photo courtesy of NASA/ESA/M.Livio/STScI

A tour of the Natural History Museum might lead you from an exhibition on dinosaurs to one about ocean creatures. You might read about how hominids evolved millions of years ago, how our planet’s continents have moved, or how early creatures evolved when the atmosphere was practically devoid of oxygen. The time scale of natural history, you realize, is almost unimaginably large.

But if you enter the museum’s new exhibition, “The Evolving Universe“—a show featuring photography from some of the most powerful telescopes ever created—you’ll find yourself even more astounded. Set against the backdrop of the known universe, the history of our dear planet seems nearly irrelevant. Hundreds of billions of stars like our sun are born out of supernovae several light years wide (each light year is longer than five trillion miles) and are destined to die, once again exploding into supernovas, billions of years later. Thousands of galaxies, some containing trillions of stars like our sun, are continuously being born and evolving.

Although these concepts can be difficult to comprehend and even harder to visualize, the stunning photos that make up the exhibition show the visitor just how awe-inspiring these astronomical events can be. They put the latest CGI graphics from 3-D blockbuster films to shame. “Part of our mission is sharing science with the public, and so we felt that doing this exhibit and showing these images is a great way to do that,” says Jonathan McDowell, an astrophysicist at the Smithsonian Astrophysical Observatory, which partnered with the museum in creating the exhibition. The large-scale photographs in the show were produced by a number of telescopes, both Earth and space-based, including the Hubble Space Telescope.

A black hole at the center of the Centaurus A galaxy spews jets of gas outward. Photo courtesy of NASA/CFX/CfA,MPiFR/ESO/APEX

“We’ve all seen the amazing pictures from NASA’s probes in our own solar system,” says McDowell. “I’m excited about bringing to the public the remarkable images of the broader universe that we astronomers have been exploring with our telescopes. I hope that with this exhibition visitors will take away an appreciation for our larger cosmic neighborhood.”

The show—and accompanying website—use these images to tell the story of our universe, from start to present. The Big Bang, the creation of galaxies, the birth of the Milky Way and the formation of our own solar system are represented in rich images so full of detail that they need to be observed for minutes at a time, like pieces of art hung on the wall.

What might be most remarkable is that the actual images created by the telescopes are themselves ancient history. Because light takes so long to travel from the far-flung reaches of space, when we photograph distant galaxies, the light that hits the camera’s lens to produce the image left its home galaxy billions of years ago. These pictures show some of the celestial objects as they were before humans even existed. And so we have a font-row seat to watch the earliest stages of the universe’s creation, if we look deep enough into space, more than 13 billion years later.

When wandering the exhibition, one might be overwhelmed by the torrent of information presented on scales that are downright otherworldly. How does our planet, so tiny and new, fit into all of this?

The best metaphor to understand earth’s place in the universe might be that of astrophysicist, author and recent Around the Mall blog subject Carl Sagan. In his book Pale Blue Dot, he describes a far-off view of the Earth from the outer reaches of the solar system:

From this distant vantage point, the Earth might not seem of any particular interest. But for us, it’s different. Look again at that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.

In the scheme of the known universe—of supernovae and galaxies and nebulas and black holes—our whole planet starts to look like a speck of dust, floating in the sunlight.

The Evolving Universe is on view at the Natural History Museum through July 7, 2013

A comparison of the two newly-discovered planets with Venus and Earth. Image courtesy of NASA/Ames/JPL-Caltech

Yesterday, scientists at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts made a major announcement. For the first time, after years of searching, Earth-sized planets had been detected outside of our solar system. Among the five planets in the distant Kepler-20 star system are Kepler-20e and Kepler-20f—two rocky orbs with diameters approximately 87 percent and 103 percent that of earth, respectively. The news has the scientific world in a state of excitement over the consequences of the find. We spoke with Smithsonian astrophysicist Francois Fressin, the lead author of the paper, about the discovery.

The Basics

Researchers have been using the Kepler space telescope since it launched in March of 2009 to search for exoplanets, or planets in other solar systems. “Kepler is staring at 200,000 stars, all located in the same area of the sky, and it just monitors the light it gets from each of the stars, continuously, for years,” says Fressin. “For a fraction of the stars, there’s a periodic dimming with the same duration and same depth of light.” This dimming can be caused by a small opaque body crossing between the star and the telescope—in this case, a pair of planets. The team first detected the telltale dimming more than a year ago, but had to make more calculations with custom-developed software to rule out the possibility that it was caused by other phenomena.

From the degree and frequency of the dimming, the scientists are able to make inferences about the planets. Kepler-20e and Kepler-20f are 6,900 miles and 8,200 miles in diameter, respectively, remarkably close to Earth’s 8,000 mile size. Because the two planets are so close to their host star—they orbit at 4.7 million miles and 10.3 million miles, both far closer in than Mercury is to the sun—they are believed to be extremely hot, with average temperatures of 1400 and 800 degrees Fahrenheit, respectively. “We know they’re both pure rock bodies,” Fressin says. “But we don’t have precise mass estimates, so we can’t say if they’re similar in composition to the Earth, or something denser with more iron, like Mercury.”

An artist's conception of Kepler-20e. Image courtesy of NASA/Ames/JPL-Caltech

What It Means For Astronomy

Exoplanet hunters began uncovering distant gas giants as early as 1992, but smaller, Earth-sized bodies had proved more difficult to detect. “We’ve crossed the threshold: this the first time that humanity is able to detect an Earth-sized object around another star,” Fressin says. ”That’s symbolically and technologically important.”

The discovery represents a historic milestone in astronomy. Now, scientists are convinced that they have the right tools to be able to detect Earth-sized planets that might support life. Researchers will continue using the Kepler space telescope to locate exoplanets in hope of finding such a world.

What It Means For Planetary Science

The discovery also turns upside-down much of what scientists believed about the formation of solar systems. The two Earth-size planets are interspersed with three gas giants, all extremely close to the host star, Kepler-20. “From the star, it goes in the order big, small, big, small, big, which seems completely weird,” says Fressin. “In our solar system, we have these four rocky small bodies, and then, farther away, these four large giant gaseous planets. So how did that happen, that we have all this mixing in the Kepler-20 system?”

Although we don’t currently have definitive answers, scientists suspect that the planets drifted into their current position over time. “They didn’t form at the place they are right now, there was not enough rocky material to build these five planets so close to their host star,” Fressin says. “So one solution would be that they formed farther out, and then migrated in.”

What It Means For Extraterrestrial Life

An artist's conception of Kepler-20f. Image courtesy of NASA/Ames/JPL-Caltech

The most tantalizing possibility of these discoveries is the potential that the exoplanets might harbor life. But both Kepler-20e and Kepler-20f are outside the habitable zone—often called the “Goldilocks” zone—that is neither too close nor too far from the host star, allowing for the evolution of living creatures. ”We don’t know a lot of things about life, but we know that one of the main ingredients of life on Earth is the presence of liquid water,” says Fressin. “Right now, at the temperatures estimated, water can’t be in a liquid state on either planet.”

Still, the hypothesis that the planets may have formed farther away, and then migrated to their current locations close to the star, means that life may have existed long ago. “It seems pretty clear that Kepler-20f once crossed the habitable zone of its host star, after its formation,” Fressin says. “It is the closest object in terms of size to the Earth in the known universe, and this means that it could have been habitable in its past.”

What It Means For Space Exploration

Although Kepler-20 is much too far to attempt as the target of a space probe mission—it’s about 950 light-years from Earth, which would require a journey of 36 million years by the space shuttle—Fressin feels that discoveries like this should stimulate interest in the very real possibility of exploring other, closer, star systems. “It would be challenging, and would require great international collaboration, maybe for one or two generations, but it would be feasible,” he says.

Such a mission would admittedly be very long-term, but the rewards are many. “I think the best location to send a probe would be to the closest sun-like star,” says Fressin. “So then imagine, in two generations, we’d have the probe coming back with pictures—real pictures—of another world.”

Dr. Pierre Comizzoli, one of the two Smithsonian scientists to receive the Presidential Award, at work in the lab. Photo courtesy Smithsonian's National Zoo

Earlier this week, President Obama announced the recipients of the annual Presidential Early Career Award for Scientists and Engineers. Among those honored were two scientists who have conducted innovative research at the Smithsonian Institution: Dr. Justin Kasper, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, and Dr. Pierre Comizzoli, a biologist at the Smithsonian Conservation Biology Institute (SCBI).

The award is the highest honor the government confers on scientists in the early stages of their careers, and is given to researchers across a wide range of disciplines.

“I’m very honored to receive this,” says Comizzoli, who was nominated through his work with the National Institutes of Health. Throughout his career, he has been involved in researching reproductive biology within a variety of species, including domestic cats, cheetahs, deer and frogs. His current research seeks to find new ways to preserve eggs and sperm without freezing.

“The project I’m working on now is exploring drying techniques, so you can keep your samples at an ambient room temperature, instead of storing them in liquid nitrogen,” he says. “It’s way more flexible, and way less expensive. And in some parts of the world, liquid nitrogen is just not available.”

Comizzoli’s work is mainly intended to preserve animal sperm and eggs as a tool for species conservation. “It’s really important to preserve the fertility of any individuals from a rare population,” he says. “If the genomes of those animals are still available to be mixed in the current population, you can preserve the genetic diversity.”

But many are excited about the potential of this research to assist in human fertility, as well. “Fertility preservation is used a lot in human reproductive medicine, for people who need to preserve their fertility before any medical treatments that are detrimental to the reproductive tissue,” Comizzoli says. “We have this fantastic opportunity at the SCBI of working with many different species and generating this huge database of comparative data, that is then extremely useful for human reproductive medicine.”

Dr. Kasper studies the transfer of energy in astrophysical objects, including the solar corona and solar wind. He received the award for his current work on the Solar Probe Plus, which will be humankind’s first mission to send a probe to the sun’s outer atmosphere.

Kasper’s research has helped with the design of SWEAP (Solar Wind Electrons Alphas and Protons) an instrument that will provide scientists with information on how the solar corona and upper atmosphere are heated. “I am honored to have received this recognition and encouragement to pursue the mysteries of our sun,” Kasper said in a press release. “By flying a spacecraft through the upper atmosphere of the sun, we will expose the fundamental physics responsible for the million-degree corona and help understand and forecast space weather.”

Kepler-16b, the first confirmed circumbinary planet. Photo courtesy of Harvard-Smithsonian Center for Astrophysics

Last week, the science world was abuzz with the news that scientists from the Harvard-Smithsonian Center for Astrophysics had discovered a distant planet with an unusual quality. Like the fictional Tatooine from Star Wars, the planet, known as Kepler-16b, is what scientists call a circumbinary: It orbits around two stars. It’s the first confirmed circumbinary planet astronomers have found.

The discovery comes from NASA’s Kepler Mission, which aims to gather information on habitable planets in the Milky Way. Josh Carter, who worked on the team that made this discovery, says they detect the presence of distant planets by a mechanism known as planetary transit. “What happens is a planet in its orbit passes in front of a star,” says Carter. “When it does that, it blocks a little light from it, just like an eclipse of the sun by the moon.”

“Of course, we can’t see the individual object, all we see is the total light coming from it,” Carter says. The light is detected by the Kepler space-based telescope. When a planet transits in front of the star during its orbit, says Carter, “you see a very small little dip in the total light from the system, and then we infer based upon its shape and basic properties that it’s an object transiting.”

This process has been used to find 21 confirmed planets so far, with thousands more potential planet candidates still being researched. But over the summer, the team noticed that one system showed dimming at irregular intervals. They realized that the multiple transits corresponded to a planet crossing in front of each star, as well as two stars crossing in front of each other. “When you see one transit in the light curve, you can guess it is the planet crossing one of the stars, but until we had three, we weren’t sure it was a circumbinary,” says Carter.

The attempt to find a circumbinary planet had been in the works for some time, Carter says. “Laurence Doyle had been looking through the collection of eclipsing stars in the catalog, and he was looking specifically for transits of a planet in a circumbinary,” says Carter. “We already had known this system had shown a single transit, but this summer with new data, we saw that there’s a total of three.”

The team further refined their understanding of Kepler-16b by using a trace spectrograph. Initially, just from studying the pattern of light emitted, they were able to establish the sizes of the stars and planet in the system, but only relative to each other. By using the spectrograph—a device that separates the light into a frequency spectrum—they could go further. “From the spectrograph, we see the velocity of the big star in the system,” says Carter. “That gives us an absolute scale with which we can learn the masses and the radii of all three objects in the system.”

Armed with this data, the researchers could then infer the planet’s composition. “We say, ‘well, it’s got this radius, it’s got this mass, what could it possibly be comprised of, what’s its structure?’” says Carter. The planet, roughly 200 light-years away from earth, is a gas giant, similar to Saturn in both size and mass.

Carter says he and his colleagues will continue searching for more circumbinary planets as they survey the wide diversity of planets in our galaxy. If they’re out there, the team will do their best to find them. “In fact,” Carter says, “we already have a few more candidate systems that we’re investigating right now.”

The Greensboro lunch counter. Photo courtesy of National Museum of American History

Friday June 17 Oh My Stars

Launch your Friday with a look into the outer limits. Thanks to the Public Observatory Project, you can view the skies at the Air and Space Museum‘s observatory between 11 a.m. and 3 p.m for your own galactic journey. After you are done exploring the wonders of the universe, participate in hands-on activities while learning about astronomy. This free event is family friendly and does not require a reservation but is weather permitting. Check with the museum’s welcome center first, but if the sky is bright come over to the Observatory, located outside the Southeast terrace near Independence Avenue and 4th Street, for an out of this world experience.

Saturday June 18 Splash Into Your Saturday

Why spend your Saturday doing the same old things when you can come to the National Portrait Gallery for a double feature that will really whet your appetite. This Saturday, Reel Portraits presents American Graffiti and Splash!.  Start your summer with a bang with American Graffiti , the film made by George Lucas before Star Wars, at 1 PM. This 1973 classic follows four young high school grads in 1962 California as they spend one last hurrah together before starting college. The film includes great cars, love stories, an amazing soundtrack and an all-star cast. Be sure not to miss Ron Howard, Harrison Ford, and Richard Dreyfuss in their Academy Award nominated performance Next up at 3 PM is the 1984 hit Splash! directed by Ron Howard. See Tom Hanks in his big screen debut as a wholesale fruit and vegetable dealer in New York. After being saved from drowning twice by a mysterious mermaid, Allen (Hanks) is called to the police station. There in the holding cell is a mysterious woman Madison, played by Darryl Hannah. Having sprouted legs for just six days Madison, Allen’s mermaid savior, is in a race against time. The film centers around the unlikely couple falling in love and the depths they go to stay together. This event is free but is on a first come, first served basis. The auditorium doors will open 30 minutes before the shows start so be sure to come early and grab your seat before it slips away.

Sunday June 19 A Greensboro Lunch

Take a few steps back in time this Sunday and join the American History Museum as they present to you the student sit-ins at the Greensboro Lunch Counter. Meet at the lunch counter on the 2nd floor of the museum’s East Wing at 1:30 Sunday afternoon to learn about a key moment in our nation’s history. Desegregation in the United States was won through many small battles, one of the most noted is the Greensboro Lunch Sit-Ins, and this Sunday you can participate in the landmark piece of history. On February 1, 1960, four male African American students from the Agricultural and Technical College of North Carolina sat down at the lunch counter of  Woolworth’s store in Greensboro, North Carolina. The Greensboro Four ordered coffee and doughnuts but were refused service at the whites only counter and were asked to leave. But the protestors – Joseph McNeil, Franklin McCain, Ezell Blair, Jr. and David Richmond – stayed until the store closed. The next day they were joined by more students at the counter and the following day resulted in an even bigger turn out. By the next week the group had started a string of sit-ins at stores all over the southern states. These sit-ins resulted in desegregation of Woolworth stores throughout the South and now it is your turn. After you take part in a training session based on an actual 1960s manual, you can prepare yourself for your fist sit-in and find out if you have the courage and strength to fight for justice in the Civil Rights movement. This free 15-to-20 minute performance reveals the people featured in the exhibits on display and allows you to experience the emotion in their stories. The performances are held Sundays and Mondays at 11:30 AM, 1:30, 3 and 4 PM.

For a complete listing of Smithsonian events and exhibitions visit the GoSmithsonian Visitors Guide.