We’re Landing A Rover On Mars In 2020…But How Do We Decide Where?

Uncovering a Massive Meteor Crater Found Lurking Under the Ice

For the first time ever, we've found a massive crater hiding under one of Earth's ice sheets. Likely caused by a meteor, it was uncovered in Greenland by a team of international scientists using radar data.

The data was collected by missions like our Operation IceBridge, which flies planes over Greenland and Antarctica to study the ice and snow at our planet’s poles.

In this case, the crater is near Hiawatha Glacier, covered by a sheet of ice more than half a mile thick. We're pretty sure that the crater was caused by a meteor because it has characteristics traditionally associated with those kinds of impacts, like a bowl shape and central peaks.

It’s also one of the 25 largest impact craters in the world, large enough to hold the cities of Paris or Washington, D.C. The meteor that created it was likely half a mile wide.

Currently, there’s still lots to learn about the crater – and the meteor that created it – but it’s likely relatively young in geologic timescales. The meteor hit Earth within the last 3 million years, but the impact could have been as recent as 13,000 years ago.

While it was likely smaller than the meteor credited with knocking out the dinosaurs, this impact could have potentially caused a large influx of fresh water into the northern Atlantic Ocean, which would have had profound impacts for life in the region at the time.

Go here to learn more about this discovery: https://www.nasa.gov/press-release/international-team-nasa-make-unexpected-discovery-under-greenland-ice

Operation IceBridge continues to uncover the hidden secrets under Earth's ice. IceBridge has been flying for 10 years, providing a data bridge between ICESat, which flew from 2003 to 2009, and ICESat-2, which launched in September. IceBridge uses a suite of instruments to help track the changing height and thickness of the ice and the snow cover above it. IceBridge also measures the bedrock below the ice, which allows for discoveries like this crater.

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Aboard the International Space Station this morning, Astronaut Kimiya Yui of the Japan Aerospace Exploration Agency (JAXA) successfully captured JAXA's Kounotori 5 H-II Transfer Vehicle (HTV-5) at 6:28 a.m. EDT.

Yui commanded the station's robotic arm, Canadarm2, to reach out and grapple the HTV-5, while NASA astronauts Kjell Lindgren provided assistance and Scott Kelly monitored HTV-5 systems. The HTV-5 launched aboard an H-IIB rocket at 7:50 a.m. Wednesday, Aug. 19, from the Tanegashima Space Center in southern Japan. Since then, the spacecraft has performed a series of engine burns to fine-tune its course for arrival at the station.

The HTV-5 is delivering more than 8,000 pounds of equipment, supplies and experiments in a pressurized cargo compartment. The unpressurized compartment will deliver the 1,400-pound CALorimetric Electron Telescope (CALET) investigation, an astrophysics mission that will search for signatures of dark matter and provide the highest energy direct measurements of the cosmic ray electron spectrum.

Below is a breathtaking image shared by Astronaut Scott Kelly of the HTV-5 and Canadarm2, which reached out and grappled the cargo spacecraft.

300 Consecutive Days in Space!

Today marks astronaut Scott Kelly’s 300th day in space! He, along with Russian cosmonaut Mikhail Kornienko, are testing the limits of human research during their one-year mission onboard the International Space Station.

While most expeditions to the space station last four to six months, their time on orbit has been doubled. By increasing the length of their time in space, researchers hope to better understand how the human body reacts and adapts to long-duration spaceflight.

What happens when you’ve been in space for 300 days?

1. You might get bored and play ping pong with yourself…and a water droplet.

2. There’s a chance that you’ll get a Tweet from someone famous…like the President!

3. There may come a time where you’ll have to fix something outside the station during a spacewalk.

4. You might develop a ‘green thumb’ and grow plants in space.

5. And, there’s no doubt you get to see the Earth from a totally new perspective.

To learn more about the one-year mission, visit: https://www.nasa.gov/1ym 

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Flying to New Heights With the Magnetospheric Multiscale Mission

A mission studying Earth’s magnetic field by flying four identical spacecraft is headed into new territory. 

The Magnetospheric Multiscale mission, or MMS, has been studying the magnetic field on the side of Earth facing the sun, the day side – but now we’re focusing on something else. On February 9, MMS started the three-month-long process of shifting to a new orbit. 

One key thing MMS studies is magnetic reconnection – a process that occurs when magnetic fields collide and re-align explosively into new positions. The new orbit will allow MMS to study reconnection on the night side of the Earth, farther from the sun.

Magnetic reconnection on the night side of Earth is thought to be responsible for causing the northern and southern lights.  

To study the interesting regions of Earth’s magnetic field on the night side, the four MMS spacecraft are being boosted into an orbit that takes them farther from Earth than ever before. Once it reaches its final orbit, MMS will shatter its previous Guinness World Record for highest altitude fix of a GPS.

To save on fuel, the orbit is slowly adjusted over many weeks. The boost to take each spacecraft to its final orbit will happen during the first week of April.

On April 19, each spacecraft will be boosted again to raise its closest approach to Earth, called perigee. Without this step, the spacecraft would be way too close for comfort -- and would actually reenter Earth’s atmosphere next winter! 

The four MMS spacecraft usually fly really close together – only four miles between them – in a special pyramid formation called a tetrahedral, which allows us to examine the magnetic environment in three dimensions.

But during orbit adjustments, the pyramid shape is broken up to make sure the spacecraft have plenty of room to maneuver. Once MMS reaches its new orbit in May, the spacecraft will be realigned into their tetrahedral formation and ready to do more 3D magnetic science.

Learn more about MMS and find out what it’s like to fly a spacecraft.

Throwback Thursday: Answers to Apollo Moon Landing Questions

The first six missions to the Moon helped us answer questions about our nearest celestial neighbor, but a curious public wanted to know more about how we did it. With the help of the NASA History Office, we’ve identified some of the most frequently asked questions surrounding the first time humans walked on the surface of another world. Read on and click here to check out our post from last week and the week before. 

Why do some shadows on the Moon appear to go in different directions?

For Apollo astronauts, the Sun wasn’t the sole source of light. The high reflectivity of the lunar surface or “albedo” means that the Moon's many craters, hills and rocks bounce sunlight to wash out the stars multiple shadows on objects. The highly uneven terrain means that shadows can have slightly different lengths, as well. For example, two astronauts standing several feet away from each other can have different shadow lengths because one may be on a slope.

While the Lunar Module itself was also reflective, Apollo astronauts had yet another bright source of light: Earth! To a moonwalker, a half-full Earth would be about 20 times brighter than a full Moon as seen from our home planet. This also explains why stars are not visible in pictures. Think about it: if you wanted to photograph all the stars that can be seen from Earth, would you want to do it during a full Moon? 

Why are there no blast craters under the Lunar Modules? 

The Moon has endured billions of years of bombardment from micrometeorites and large meteorites, compacting the dust into extremely dense rock. A thin layer of fine and powdery moondust covers the ground, but the dense rock beneath this layer makes it hard to penetrate the surface. That, paired with an engine thrusting in a vacuum means that the exhaust would expand rapidly outward instead of straight down like it would on Earth. The large engine nozzle. Still, many pictures clearly show dust markings radiating from the landing site. 

Can Humans Really Survive Passing Through the Van Allen Radiation Belts?

The short answer is yes, but with protection. The Van Allen radiation belts, named after their discoverer James van Allen, are regions high above Earth’s surface that trap highly charged particles that radiate off the Sun. This energetic region contains harmful radiation that would be lethal to anybody who encountered them unprotected. Thankfully, the 12 astronauts that passed through the belts did so relatively quickly in the comfort of their shielded spacecraft that had been tested to withstand high doses of radiation. Although all six crews had to pass through the Van Allen belts, the dosimeters indicated that they received a dosage no higher than that of a chest X-ray or a single CAT scan. 

Why are we going back to the Moon?

Exploring the Moon is only the first part in our mission to expand humanity’s presence on Mars and beyond. The Moon is the ideal stepping stone for testing technology that will enable us to expand humanity’s presence on Mars and beyond. Click here to learn more about the Artemis program that will take humans to the lunar surface within five years -- this time, to stay. Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Questions coming up from….

@teamadamsperret: Congrats on your PhD!! When people ask what you do, what's your reply?

@Anonymous: How does it feel, working in NASA?

@moonlighy: How did you find your love for this job?

@redbullanddepression: what the prettiest star in the sky in your opinion? also, you are a great role model as a queer woman who is attending university next year to major in aerospace engineering!!!

The trickster “Blinking Planetary”

Planetary nebula NGC 6826 is located about 4,200 light years from Earth in Cygnus. When observers look directly at it through a small telescope, they typically see only the nebula’s sparkling-white central star. However, by averting one’s gaze, glancing away from the central star, the nebula’s bulbous dust clouds come into view. This optical trickery earned this planetary nebula the name the "Blinking Planetary.” 

Over the next several thousand years, the nebula will gradually disperse into space, and then the central star will slowly cool as it radiates its energy for billions of years as a white dwarf. 

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GALAXY BRAIN 🧠

Our Hubble Space Telescope spotted this planetary nebula in the constellation of Orion. It's really a vast orb of gas in space, with its aging star in the center... but what does it look like to you? 🤔

When stars like the Sun grow advanced in age, they expand and glow red. These so-called red giants then begin to lose their outer layers of material into space. More than half of such a star's mass can be shed in this manner, forming a shell of surrounding gas. At the same time, the star's core shrinks and grows hotter, emitting ultraviolet light that causes the expelled gases to glow.

Why are bacteria resistant polymers being experimented, specifically in microgravity?

What would happen if I go into a black hole? Do you think I would disappear forever or would I still exist inside the black hole?