The universe suddenly looks a lot more crowded…
We already estimated that there were about 100 billion galaxies in the observable universe, but new research shows that this estimate is at least 10 times too low!
First, what is the observable universe? Well, it is the most distant part of the universe we can see from Earth because, in theory, the light from these objects have had time to reach Earth.
In a new study using surveys taken by the Hubble Space Telescope and other observatories, astronomers came to the surprising conclusion that there are at least 10 times more galaxies in the observable universe than previously thought. This places the universe’s estimated population at, minimally, 2 trillion galaxies!
The results have clear implications for galaxy formation, and also helps shed light on an ancient astronomical paradox – why is the sky dark at night?
Most of these newly discovered galaxies were relatively small and faint, with masses similar to those of the satellite galaxies surrounding the Milky Way.
Using deep-space images from the Hubble Space Telescope and other observatories, astronomers converted the images into 3-D, in order to make accurate measurements of the number of galaxies at different epochs in the universe’s history.
In addition, they used new mathematical models, which allowed them to infer the existence of galaxies that the current generation of telescopes cannot observe. This led to the surprising conclusion that in order for the numbers of galaxies we now see and their masses to add up, there must be a further 90% of galaxies in the observable universe that are too faint and too far away to be seen with present-day telescopes.
The myriad small faint galaxies from the early universe merged over time into the larger galaxies we can now observe.
That means that over 90% of the galaxies in the universe have yet to be studied! In the near future, the James Webb Space Telescope will be able to study these ultra-faint galaxies and give us more information about their existence.
So back to the question…Why is the sky dark at night if the universe contains an infinity of stars? Researchers came to the conclusion that indeed there actually is such an abundance of galaxies that, in principle, every patch in the sky contains part of a galaxy.
However, starlight from the galaxies is invisible to the human eye and most modern telescopes due to other known factors that reduce visible and ultraviolet light in the universe. Those factors are the reddening of light due to the expansion of space, the universe’s dynamic nature, and the absorption of light by intergalactic dust and gas. All combined, this keeps the night sky dark to our vision.
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Twinkle, twinkle, little star, How I wonder what you are. Up above the world so high, Like a diamond in the sky. 🌟 The final stages of a star’s life allow us a glimpse into the future of our own solar system. This image from our Hubble Space Telescope shows what’s left of a star 10,000 light-years from Earth.
A star like our Sun will, at the end of its life, transform into a red giant. The core of the star will eventually collapse in on itself, ejecting the surface layers outward. After that, all that remains of the star is what we see here: glowing outer layers surrounding a white dwarf star. In just a few thousand years they will have dissipated, and all that will be left to see is the dimly glowing white dwarf. More on this image, here.
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CubeSats are a class of research spacecraft called nanosatellites. They provide low-cost opportunities for small satellite payloads to fly on rockets planned for upcoming launches. Small satellites, including CubeSats, are playing an increasingly larger role in exploration, technology demonstration, scientific research and educational investigations here at NASA.
Fourteen miniature satellites were deployed from the International Space Station earlier this week. Two of the CubeSats were Danish and have communication and ship signal tracking capabilities. The remaining are Dove satellites from Planet Labs and will take images of Earth from space.
On Thursday, Oct. 8, thirteen CubeSats are scheduled to launch aboard a United Launch Alliance Atlas V rocket at 8:49 a.m. EDT. Watch live on NASA TV starting at 8:29 a.m. http://www.nasa.gov/nasatv
To learn more about tomorrow’s launch, watch NASA Television today, Oct. 7 at 1 p.m. and 2 p.m. EDT. The briefings will highlight the growing importance of CubeSats in space exploration.
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We’re launching Landsat 9 — the ninth in a series of satellite missions from NASA and the U.S. Geological Survey (USGS) that have been collecting images of our planet for almost 50 years. Follow along as we count down to launch!
A normal launch countdown starts at 10, but for Landsat 9, we’re jumping in with L-9!
There are 9 million images in the USGS/NASA Landsat archive! They’re all available for free, for use by scientists, data managers, and anyone else who’s interested. You can even download them!
Landsat 9 won’t be orbiting alone. Working together, Landsat 9 and Landsat 8 will completely image Earth every 8 days! This helps us track changes on the planet’s surface as they happen in near-real-time.
Landsat sees all 7 continents! From Antarctic ice to growing cities to changing forests, Landsat measures land — and coastal regions — all around the globe.
Working in space is really hard. Landsat 6 never made it to orbit, an important reminder that failures can be opportunities to learn and grow. Shortly after the unsuccessful launch, engineers got to work on Landsat 7, which is still collecting data today — 22 years later.
We have 5 decades of Landsat observations, the longest continuous record of Earth’s land surfaces in existence! While building the original Landsat in the 1970s, it would have been hard to imagine that this mission would still be providing crucial data about our planet today.
For each color band collected, Landsat 9 will see 4 times the shades of light as the previous Landsat mission! With more than 16,000 different intensities detected, Landsat 9 will be able to see crucial details on our planet’s surface.
Our eyes detect 3 colors of light: red, green, and blue — and Landsat does too! But Landsat 9 also detects wavelengths that can be combined to measure things our eyes can’t, like crop stress, coral reef health, fires, and more.
There are 2 instruments on Landsat 9! The Operational Land Imager 2 collects light, and works kind of like our eyes — or cameras — to make data-rich images. The Thermal Infrared Sensor 2 measures temperature, helping monitor plant health, fires, and more.
The Landsat program is the result of 1 amazing partnership! For more than 50 years, we’ve worked with the U.S. Geological Survey to design, build, launch, and manage Landsat satellites.
Two agencies working together makes for the longest continuous record of Earth’s surfaces. Now, let’s launch this satellite!
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What is your advise to people who wanna be astronaut?
How do you know if your solar eclipse glasses are legit?
Make sure to see that it has the ISO 12312-2 compliant and check that it’s from a trusted vendor. You can find a link here https://eclipse2017.nasa.gov/safety with more information and links to lists of trusted vendors.
It’s World Photography Day!
To celebrate the occasion, we’re sharing photos from our photographers that chronicle what's making news across the agency - from launches and landings to important science announcements to images taken from the vantage point of space.
Take a look!
Posted to Twitter by European Space Agency astronaut Alexander Gerst, this image shows our planet's Moon as seen from the International Space Station. As he said in the tweet, "By orbiting the Earth almost 16 times per day, the #ISS crew travel the distance to the Moon and back – every day. #Horizons"
The International Space Station is the world's only orbital laboratory. An international partnership of space agencies provides and operates the elements of the station. The principals are the space agencies of the United States, Russia, Europe, Japan and Canada.
Photo Credit: NASA
NASA astronaut Ricky Arnold took this selfie during the May 16, 2018, spacewalk to perform upgrades on the International Space Station, saying in a tweet "An amazing view of our one and only planet."
Arnold and fellow spacewalker Drew Feustel donned spacesuits and worked for more than six hours outside the station to finish upgrading cooling system hardware and install new and updated communications equipment for future dockings of commercial crew spacecraft.
Photo Credit: NASA
The mobile service tower at Space Launch Complex-3 is rolled back to reveal the United Launch Alliance Atlas-V rocket with NASA’s InSight spacecraft onboard, Friday, May 4, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core.
Photo Credit: NASA/Bill Ingalls
The United Launch Alliance Delta IV Heavy rocket is seen in this long exposure photograph as it launches NASA's Parker Solar Probe to touch the Sun, Sunday, Aug. 12, 2018 from Launch Complex 37 at Cape Canaveral Air Force Station, Florida. Parker Solar Probe is humanity’s first-ever mission into a part of the Sun’s atmosphere called the corona. Here it will directly explore solar processes that are key to understanding and forecasting space weather events that can impact life on Earth.
Photo Credit: NASA/Bill Ingalls
Expedition 56 flight engineer Serena Auñón-Chancellor of NASA waves farewell to family and friends as she and Soyuz Commander Sergey Prokopyev of Roscosmos and flight engineer Alexander Gerst of European Space Agency depart Building 254 for the launch pad a few hours before their launch, Wednesday, June 6, 2018 at the Baikonur Cosmodrome in Kazakhstan. Auñón-Chancellor, Prokopyev, and Gerst launched aboard the Soyuz MS-09 spacecraft at 7:12am EDT (5:12pm Baikonur time) on June 6 to begin their journey to the International Space Station.
Photo Credit: NASA/Victor Zelentsov
The Soyuz MS-09 rocket is launched with Expedition 56 Soyuz Commander Sergey Prokopyev of Roscosmos, flight engineer Serena Auñón-Chancellor of NASA, and flight engineer Alexander Gerst of ESA (European Space Agency), Wednesday, June 6, 2018 at the Baikonur Cosmodrome in Kazakhstan. Prokopyev, Auñón-Chancellor, and Gerst will spend the next six months living and working aboard the International Space Station.
Photo Credit: NASA/Joel Kowsky
In an effort to improve fuel efficiency, NASA and the aircraft industry are rethinking aircraft design. Inside the 8’ x 6’ wind tunnel at NASA Glenn Research Center, engineers tested a fan and inlet design, commonly called a propulsor, which could use four to eight percent less fuel than today’s advanced aircraft.
Photo Credit: NASA/Rami Daud
SOFIA, the Stratospheric Observatory for Infrared Astronomy, is the largest airborne observatory in the world, capable of making observations that are impossible for even the largest and highest ground-based telescopes. During its lifetime, SOFIA also will inspire the development of new scientific instrumentation and foster the education of young scientists and engineers.
Photo Credit: NASA/SOFIA/Waynne Williams
A close-up view of crystals that developed on materials exposed to conditions on Venus in NASA Glenn’s Extreme Environments Rig. This unique and world class ground-based test rig can accurately most simulate atmospheric conditions for any planet or moon in the solar system and beyond.
Photo Credit: NASA/Bridget Caswell
A close-up view of 3-D printed honeycomb patterns made in NASA Glenn manufacturing lab using a method called binder jetting. The honeycomb structures can find use in several applications such as a strong core for lightweight sandwich panels, acoustic panels for noise attenuation and innovative cellular structures.
Photo Credit: NASA/Marvin Smith
To see even more photos of our space exploration efforts, visit us on Flickr: https://www.flickr.com/photos/nasahqphoto/.
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As an astronaut who has been on a spacewalk before, what does the all-woman spacewalk mean to you?
When will we start seeing images from the James Webb telescope??
Launched less than four months after Apollo 11 put the first astronauts on the Moon, Apollo 12 was more than a simple encore. After being struck by lightning on launch -- to no lasting damage, fortunately -- Apollo 12 headed for a rendezvous with a spacecraft that was already on the Moon. The mission would expand the techniques used to explore the Moon and show the coordination between robotic and human exploration, both of which continue today as we get return to return astronauts to the Moon by 2024.
Apollo 12 lifted off at 11:22 a.m. EST, Nov. 14, 1969, from our Kennedy Space Center. Aboard the Apollo 12 spacecraft were astronauts Charles Conrad Jr., commander; Richard F. Gordon Jr., command module pilot; and Alan L. Bean, lunar module pilot.
Barely 40 seconds after liftoff, lightning struck the spacecraft. Conrad alerted Houston that the crew had lost telemetry and other data from the mission computers. As the Saturn V engines continued to push the capsule to orbit, ground controllers worked out a solution, restarting some electrical systems, and Apollo 12 headed toward the Moon.
Cameras at the Kennedy Space Center captured this image of the same lightning bolt that struck Apollo 12 striking the mobile platform used for the launch.
Apollo 12 landed on the Moon on Nov. 19, and on the second moonwalk Conrad and Bean walked approximately 200 yards to the Surveyor 3 spacecraft. One of seven Surveyor spacecraft sent to land on the Moon and to gather data on the best way to land humans there, Surveyor 3 had been on the Moon for more than two years, exposed to cosmic radiation and the vacuum of space. Scientists on the ground wanted to recover parts of the spacecraft to see what effects the environment had had on it.
Apollo 12 commander Pete Conrad examines the Surveyor 3 spacecraft before removing its camera and other pieces for return to Earth. In the background is the lunar module that landed Conrad and lunar module pilot Alan Bean on the Moon.
Apollo 12 splashed down on Nov. 24. When Artemis returns astronauts to the Moon in 2024, it will be building on Apollo 12 as much as any of the other missions. Just as Apollo 12 had to maneuver off the standard “free return” trajectory to reach its landing site near Surveyor, Artemis missions will take advantage of the Gateway to visit a variety of lunar locations. The complementary work of Surveyor and Apollo -- a robotic mission preparing the way for a crewed mission; that crewed mission going back to the robotic mission to learn more from it -- prefigures how Artemis will take advantage of commercial lunar landers and other programs to make lunar exploration sustainable over the long term.
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sorry, i don't know much about earth science (though it sounds very intriguing), but - what exactly is it that you do? does it take a lot of time? is it fun but challenging? was it hard to get your job? have you always wanted to work with earth science?
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