Illustration of the ESA Planck Telescope in Earth orbit (Credit: ESA)
In 1964 the European Launcher Development Organisation (ELDO) and the European Space Research Organisation (ESRO) were founded, on February 29 and March 20 respectively, marking the beginning of Europe as a major space power and player in the new international venture to explore beyond our planet. A decade later these two entities merged to become ESA, and the rest, as it’s said, is history.
The video above commemorates ESA’s service to the cooperation and innovation of European nations in space, and indeed the entire world with many of the far-reaching exploration missions its member states have developed, launched and maintained. From advanced communications and observational satellites to its many missions exploring the worlds of the Solar System to capturing the light from the beginning of the Universe, ELDO, ESRO, and ESA have pushed the boundaries of science and technology in space for half a century… and are inspiring the next generation to continue exploring into the decades ahead. So happy anniversary, ESA — I can only imagine what we might be looking back on in another 50 years!
Source: ESA. See more key dates from ESA’s history here.
One of the highest-resolution images of Mercury's surface ever acquired.
Are you ready for a good close look at Mercury? At an incredible 5 meters per pixel, this is one of the highest-resolution images of Mercury’s surface ever captured. It was acquired on March 15 with the MESSENGER spacecraft’s MDIS (Mercury Dual Imaging System) instrument and shows an 8.3-km (5.2-mile) -wide section of Mercury’s north polar region, speckled with small craters and softly rolling hills.
Because MESSENGER was moving so quickly relative to the targeted area it was imaging, a short exposure time was necessary to avoid blurring. As a result the image appears a bit grainy. See the original map projection here.
Wondering what the next-best image was of Mercury? Find out below:
The previous record for most extreme close-up of Mercury was held by this image:
7 meter/pixel targeted observation of Mercury by the MESSENGER spacecraft
It was acquired as a targeted observation by MESSENGER’s Narrow-Angle Camera on April 30, 2012, and has a resolution of 7 meters/pixel. It shows an impact melt-covered area about 11 km (7 miles) across near Gaugin crater.
(Although Mercury’s surface may at first appear strikingly similar to the Moon’s, it’s been known since the Mariner 10 mission that the two worlds are very different at fundamental geologic and compositional levels. Read more on that here.)
Images like these are extremely special; during the first two years of MESSENGER’s mission in orbit around Mercury, over 150,000 images were acquired but only five images had resolutions better than 10 meters per pixel.
Artist’s impression of MESSENGER orbiting Mercury
On April 20, 2014, MESSENGER completed its 3,000th orbit of Mercury (3,075 to date) and is steadily moving into an even lower-altitude orbit. MESSENGER now comes within less than 200 km (124 miles) of the planet’s surface when it passes over its north pole every eight hours… that’s less than half the altitude of the Space Station!
Orbiting at such a low altitude and so often will allow MESSENGER to examine Mercury’s surface in unprecedented detail. Now that 100% of the planet has been successfully mapped by MESSENGER it can spend its second — and last — extended mission investigating specific scientific targets.
“The final year of MESSENGER’s orbital operations will be an entirely new mission,” said Sean Solomon, Principal Investigator for MESSENGER. “With each orbit, our images, our surface compositional measurements, and our observations of the planet’s magnetic and gravity fields will be higher in resolution than ever before. We will be able to characterize Mercury’s near-surface particle environment for the first time. Mercury has stubbornly held on to many of its secrets, but many will at last be revealed.”
Read more in a recent news release from the MESSENGER team here.
Want to explore a high-res map of Mercury and see where MESSENGER is right now? Click here.
Image credits: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Uranus as seen by Cassini on July 19, 2013 (NASA/JPL-Caltech/SSI)
When you hear the words “pale blue dot” you’re probably reminded of the famous quote by Carl Sagan inspired by an image of Earth as a soberingly tiny speck, as imaged by Voyager 1 on Feb. 14, 1990 from beyond the orbit of Pluto. But there’s another pale blue world in our Solar System: the ice giant Uranus, and its picture was captured much more recently by the Cassini spacecraft from orbit around Saturn on April 11, 2014.
Released today by the Cassini Imaging Team, the image above shows Uranus as a tiny blue orb shining far beyond the bright hazy bands of Saturn’s F ring.
“Do you relish the notion of being a Saturnian, and gazing out from the lofty heights of Saturn at the same planets we see here from the Earth?”
– Carolyn Porco, Cassini Imaging Team Leader
Uranus’ coloration is a result of methane high in its frigid atmosphere. According to the description on the CICLOPS site, “methane on Uranus — and its sapphire-colored sibling, Neptune — absorbs red wavelengths of incoming sunlight, but allows blue wavelengths to escape back into space, resulting in the predominantly bluish color seen here.”
This was also the first time Uranus had been imaged by the Cassini spacecraft, which has been in orbit around Saturn since 2004. In fact its ten-year orbital anniversary will come on July 1.
This image adds one more planet to the list of worlds captured on Camera by Cassini, which made headlines last fall when a glorious mosaic was released that featured a backlit Saturn in eclipse surrounded by its luminous rings, the specks of several of its moons, and the distant dots of Venus, Mars, and the Earth and Moon. Made from 141 separate exposures, the mosaic was captured on July 19, 2013 — known by many space aficionados as “the day the Earth smiled” as it was the first time the world’s population was alerted beforehand that its picture would be taken from over 900 million miles away.
Saturn — with its terrestrial spacecraft in tow — was about 28.6 AU away from Uranus when the image was acquired. That’s about 4.28 billion kilometers (2.66 billion miles). From that distance the glow of the 51,118-kilometer (31,763-mile) -wide Uranus is reduced to a mere few pixels (which required digital brightening by about 4.5x, as well.)
MESSENGER image of Mercury from its third flyby (NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)
Whatever Mercury’s did to trim down its waistline has worked better than anyone thought — the innermost planet in our Solar System has reduced its radius* by about 7 kilometers (4.4 miles), over double the amount once estimated by scientists.
Of course you wouldn’t want to rush to begin the Mercury diet — its planetary contraction has taken place over the course of 3.8 billion years, since the end of the Late Heavy Bombardment. Still — lookin’ good, Mercury!
These findings come thanks to the MESSENGER spacecraft, in orbit around Mercury since 2011. Now that MESSENGER has successfully mapped literally all of Mercury’s surface, detailed measurements of more than 5,900 landforms created by cooling and contraction of the planet’s crust have allowed researchers to more precisely determine its geologic history and answer some decades-old questions raised by Mariner 10 images.
“This discrepancy between theory and observation, a major puzzle for four decades, has finally been resolved,” said MESSENGER Principal Investigator Sean Solomon. “It is wonderfully affirming to see that our theoretical understanding is at last matched by geological evidence.”
This image shows a fold-and-thrust belt stretching over 540 km on Mercury. The colors correspond to elevation— yellow/green is high and blue is low. (Courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.)
Using high-definition images acquired with MESSENGER’s MDIS (Mercury Dual Imaging System) instrument, planetary geologist at the Carnegie Institution of Washington and study lead author Paul Byrne and his colleagues identified 5,934 lobate scarps and wrinkle ridges on Mercury that are the result of contraction. From measurements of these features, the team determined that the planet’s radial contraction was much more than that estimated by models based on incomplete imaging from NASA’s Mariner 10 mission — the very first spacecraft to visit (but not orbit) Mercury.
“These new results resolved a decades-old paradox between thermal history models and estimates of Mercury’s contraction,” said Byrne. “Now the history of heat production and loss and global contraction are consistent.
“Interestingly, our findings are also reminiscent of now-obsolete models for how large-scale geological deformation occurred on Earth when the scientific community thought that the Earth only had one tectonic plate,” Byrne said. “Those models were developed to explain mountain building and tectonic activity in the nineteenth century, before plate tectonics theory.”
Unlike Earth, Mercury has only one global tectonic plate.
The findings were published in the Sunday, March 16 edition of the journal Nature Geoscience.
One of my favorite pet peeves is the inability of conventional models to accurately convey the gigantic scale of the Solar System. Most of us grew up with models of the planets made of wood or plastic or spray painted styrofoam balls impaled on bent wire hangers (don’t tell Mommy), or, more commonly, illustrations on posters and in textbooks. While these can be fun to look at and even show the correct relative sizes of the planets (although usually not as compared to the Sun) there’s one thing that they simply cannot relate to the viewer: space is really, really, really big.
Now there are some more human-scale models out there that do show how far the planets are from each other, but many of them require some walking, driving, or even flying to traverse their full distances. Alternatively, thanks to the magic of web pages which can be any size you like limited only by the imagination of the creator (and the patience of the viewer), accurate models can be easily presented showing the average (read: mind-blowingly enormous) distances between the planets… and no traveling or wire hangers required.
Despite their similar apparent sizes in our sky, the Moon and Sun are (obviously) quite different in actual size. Which is a good thing for us. (Credit: Josh Worth)
Created by designer Josh Worth, “If the Moon Were Only 1 Pixel: A Tediously Accurate Scale Model of the Solar System” uses a horizontally-sliding HTML page to show how far it is from one planet to another, as well as their relative sizes, based on our Moon being just a single pixel in diameter (and everything lined up neatly in a row, which it never is.) You can use the scroll bar at the bottom of the page or arrow keys to travel the distances or, if you want to feel like you’re at least getting some exercise, scroll with your mouse or computer’s swipe pad (where applicable.) You can also use the astronomical symbols at the top of the page to “warp” to each planet.
Just try not to miss anything — it’s a surprisingly big place out there.
“You may think it’s a long way down the road to the chemist’s, but that’s just peanuts to space.”
Infrared image of comet NEOWISE (C/2014 C3). Credit: NASA/JPL-Caltech
NASA’s NEOWISE mission — formerly known as just WISE — has identified the first comet of its new near-Earth object hunting career… and, according to mission scientists, it’s a “weirdo.”
In its former life NASA’s WISE (Wide-field Infrared Survey Explorer) spacecraft scanned the entire sky in infrared wavelengths. It helped discover the galaxy’s coldest stars, the Universe’s brightest galaxies, and some of the darkest asteroids lurking in the main asteroid belt between Mars and Jupiter… as well as closer in to Earth’s neck of the woods.
After exhausting its supply of liquid coolant needed to shield itself from its own radiating heat, in 2011 WISE was put into a state of hibernation. It was awoken last year and rebranded NEOWISE, and set upon the task of locating unknown objects with orbits in the proximity of Earth’s.
Artist’s impression of the WISE satellite
To date several new asteroids have already been found by NEOWISE, and on February 14, 2014, it spotted its first comet.
“We are so pleased to have discovered this frozen visitor from the outermost reaches of our solar system,” said Amy Mainzer, NEOWISE principal investigator at JPL. “This comet is a weirdo — it is in a retrograde orbit, meaning that it orbits the sun in the opposite sense from Earth and the other planets.”
Designated “C/2014 C3 (NEOWISE),” the comet was 143 million miles (230 million km) away in the image above — a composite made from six infrared exposures. That’s 585 times the distance to the Moon, or about the average distance between the Earth and Mars.
The tail of the comet NEOWISE extends about 25,000 miles (40,000 km) to the right in the image.
Overall, C/2014 C3 (NEOWISE) was spotted six times before it moved out of range of the spacecraft’s view. The comet has a highly-eccentric 20-year orbit that takes it high above the plane of the Solar System and out past the orbit of Jupiter. Technically, with a perihelion distance greater than 1.3 AU, comet C/2014 C3 does not classify as a near-Earth object (and its orbit does not intersect Earth’s.) But it’s still good to know that NEOWISE is looking out for us.
We’ve all seen charts showing the relative sizes of planets and moons compared to each other, which are cool to look at but don’t really give a sense of the comparative masses of the various worlds in our Solar System. It’s one thing to say the Earth is four times larger than the Moon, it’s entirely another to realize it’s 87 times more massive!
That’s where this new animation from astrophysicist Rhys Taylor comes in nicely.
This artist's rendering shows NASA's Europa Clipper spacecraft, which is scheduled to launch in October, 2024. It'll have to contend with Jupiter's powerful radiation. Will a newly-found low-radiation path to Europa help? Image Credit: NASA/JPL
Forget Mars, the place we really want to go looking for life is Jupiter’s moon Europa. Dr. Mike Brown, a professor of planetary science at Caltech, explains what he finds so fascinating about this icy moon, and the potential we might find life swimming in its vast oceans. Continue reading “Why Europa?”
You’ve probably heard the saying “everything’s relative”. When you consider our place in the Universe, everything really is relative. I’m recording this halfway up Vancouver Island, in the Pacific Ocean, off the West Coast of Canada. And where I’m standing is about 6,370 kilometers away from the center of the Earth, that way.
From my perspective, the Sun is over there. It’s as large as a dime held at arm’s length. For me it’s really, really far away. In fact, at this exact time it’s further away than any object I you can see with the naked eye.I’m about 150 million kilometers away from the Sun, and so are you.
We’re carving out an elliptical orbit which takes one full year to complete one whole trip around. You, me and the Earth are all located inside our Solar System. Which contains the Sun, 8 planets and a vast collection of ice, rocks and dust. We’re embedded deep within our galaxy, the Milky Way. It’s a big flat disk of stars measuring up to 120,000 light years across.
Our Solar System is located in the middle of this galactic disk. And by the middle, I mean the center of the galaxy is about 27,000 light years that way, and the edge of the galaxy is about the same distance that way.
Our Milky Way is but one galaxy in a larger collection of galaxies known as the Local Group. There are 36 known objects in the local group. Which are mostly dwarf galaxies. However, there’s also the Triangulum Galaxy, the Milky Way, and the Andromeda galaxy… which is by far the largest, most massive object in the Local Group, It’s twice the size and 4 times the mass of the Milky Way.
But where is it?
Milky Way. Image credit: NASA
From me, and you, Andromeda is located just an astronomically distant 2.5 million light years that way. Or would that be just short 2.5 million light-years that away? I’m sure you see where this is going.
The Local Group is embedded within a much larger group known as the Virgo Supercluster, containing at least 100 galaxy groups and clusters. The rough center of the supercluster is in the constellation Virgo. Which as of right now, is that way, about 65 million light years away. Which certainly makes the 2.5 million light years to Andromeda seem like an afternoon jaunt in the family car.
Unsurprisingly, The Virgo Supercluster is a part of a larger structure as well. The Pisces-Cetus Supercluster Complex. This is a vast filament of galactic superclusters measuring about 150 million light years across AND a billion light years long. The middle is just over that way. Right over there.
Andromeda Galaxy. Credit: Fabio Bortoli
One billion light years in length? Well that makes Andromeda seem right around the corner. So where are we? Where are you, and I and the Earth located in the entire Universe? The edge of the observable Universe is about 13.8 billion light years that way. But it’s also 13.8 billion light years that way. And that way, and that way.
And cosmologists think that if you travel in any direction long enough, you’ll return to your starting point, just like how you can travel in any one direction on the surface of the Earth and return right back at your starting point. In other words, the Earth is located at the very, very center of the Universe. Which sounds truly amazing.
What a strange coincidence for you and I to be located right here. Dead center. Smack dab right in the middle of the Universe. Certainly makes us sound important doesn’t it? But considering that every other spot in the Universe is also located at the center of the universe.
You heard me right. Every single spot that you can imagine inside the Universe is also the center of the Universe. That definitely complicates things in our plans for Universal relevance. And all this sure does make Andromeda seem close by….and it’s still just right over there, at the center of the Universe. Oh, and about every spot in the universe being the center of the Universe? Well, we’ll save that one for another episode.
Anyone who’s ever seen a map or a globe easily knows that the surface of our planet is mostly covered by liquid water — about 71%, by most estimates* — and so it’s not surprising that all Earthly life as we know it depends, in some form or another, on water. (Our own bodies are composed of about 55-60% of the stuff.) But how did it get here in the first place? Based on current understanding of how the Solar System formed, primordial Earth couldn’t have developed with its own water supply; this close to the Sun there just wouldn’t have been enough water knocking about. Left to its own devices Earth should be a dry world, yet it’s not (thankfully for us and pretty much everything else living here.) So where did all the wet stuff come from?
As it turns out, Earth’s water probably wasn’t made, it was delivered. Check out the video above from MinuteEarth to learn more.
*71% of Earth’s surface, yes, but actually less total than you might think. Read more.
MinuteEarth (and MinutePhysics) is created by Henry Reich, with Alex Reich, Peter Reich, Emily Elert, and Ever Salazar. Music by Nathaniel Schroeder.
UPDATE March 2, 2014: recent studies support an “alien” origin of Earth’s water from meteorites, but perhaps much earlier in its formation rather than later. Read more from the Harvard Gazette here.
