I never get tired of this photo, and will post it again and again. In the words of Carl Sagan…a pale blue dot.
Take a moment to contemplate our home in the grand scheme of the universe. In the middle of petty squabbles and power grabs, in the end, we are adrift on our cosmic journey. We need to take better care of our “spaceship”.
And for those who do not care or would not hesitate to screw our home over to make some money, I’d love to banish you to Venus.
From deep below the soil at Earth’s polar regions to Pluto’s frozen heart, ice exists all over the solar system…and beyond. From right here on our home planet to moons and planets millions of miles away, we’re exploring ice and watching how it changes. Here’s 10 things to know:
1.Earth’s Changing Ice Sheets
An Antarctic ice sheet. Credit: NASA
Ice sheets are massive expanses of ice that stay frozen from year to year and cover more than 6 million square miles. On Earth, ice sheets extend across most of Greenland and Antarctica. These two ice sheets contain more than 99 percent of the planet’s freshwater. However, our ice sheets are sensitive to the changing climate.
Data from our GRACE satellites show that the land ice sheets in both Antarctica and Greenland have been losing mass since at least 2002, and the speed at which they’re losing mass is accelerating.
2. Sea Ice at Earth’s Poles
Earth’s polar oceans are covered by stretches of ice that freezes and melts with the seasons and moves with the wind and ocean currents. During the autumn and winter, the sea ice grows until it reaches an annual maximum extent, and then melts back to an annual minimum at the end of summer. Sea ice plays a crucial role in regulating climate – it’s much more reflective than the dark ocean water, reflecting up to 70 percent of sunlight back into space; in contrast, the ocean reflects only about 7 percent of the sunlight that reaches it. Sea ice also acts like an insulating blanket on top of the polar oceans, keeping the polar wintertime oceans warm and the atmosphere cool.
Some Arctic sea ice has survived multiple years of summer melt, but our research indicates there’s less and less of this older ice each year. The maximum and minimum extents are shrinking, too. Summertime sea ice in the Arctic Ocean now routinely covers about 30-40 percent less area than it did in the late 1970s, when near-continuous satellite observations began. These changes in sea ice conditions enhance the rate of warming in the Arctic, already in progress as more sunlight is absorbed by the ocean and more heat is put into the atmosphere from the ocean, all of which may ultimately affect global weather patterns.
3. Snow Cover on Earth
Snow extends the cryosphere from the poles and into more temperate regions.
Snow and ice cover most of Earth’s polar regions throughout the year, but the coverage at lower latitudes depends on the season and elevation. High-elevation landscapes such as the Tibetan Plateau and the Andes and Rocky Mountains maintain some snow cover almost year-round. In the Northern Hemisphere, snow cover is more variable and extensive than in the Southern Hemisphere.
Snow cover the most reflective surface on Earth and works like sea ice to help cool our climate. As it melts with the seasons, it provides drinking water to communities around the planet.
4. Permafrost on Earth
Tundra polygons on Alaska’s North Slope. As permafrost thaws, this area is likely to be a source of atmospheric carbon before 2100. Credit: NASA/JPL-Caltech/Charles Miller
Permafrost is soil that stays frozen solid for at least two years in a row. It occurs in the Arctic, Antarctic and high in the mountains, even in some tropical latitudes. The Arctic’s frozen layer of soil can extend more than 200 feet below the surface. It acts like cold storage for dead organic matter – plants and animals.
In parts of the Arctic, permafrost is thawing, which makes the ground wobbly and unstable and can also release those organic materials from their icy storage. As the permafrost thaws, tiny microbes in the soil wake back up and begin digesting these newly accessible organic materials, releasing carbon dioxide and methane, two greenhouse gases, into the atmosphere.
Two campaigns, CARVE and ABoVE, study Arctic permafrost and its potential effects on the climate as it thaws.
5. Glaciers on the Move
Did you know glaciers are constantly moving? The masses of ice act like slow-motion rivers, flowing under their own weight. Glaciers are formed by falling snow that accumulates over time and the slow, steady creep of flowing ice. About 10 percent of land area on Earth is covered with glacial ice, in Greenland, Antarctica and high in mountain ranges; glaciers store much of the world’s freshwater.
Our satellites and airplanes have a bird’s eye view of these glaciers and have watched the ice thin and their flows accelerate, dumping more freshwater ice into the ocean, raising sea level.
6. Pluto’s Icy Heart
The nitrogen ice glaciers on Pluto appear to carry an intriguing cargo: numerous, isolated hills that may be fragments of water ice from Pluto’s surrounding uplands. NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
Pluto’s most famous feature – that heart! – is stone cold. First spotted by our New Horizons spacecraft in 2015, the heart’s western lobe, officially named Sputnik Planitia, is a deep basin containing three kinds of ices – frozen nitrogen, methane and carbon monoxide.
Models of Pluto’s temperatures show that, due the dwarf planet’s extreme tilt (119 degrees compared to Earth’s 23 degrees), over the course of its 248-year orbit, the latitudes near 30 degrees north and south are the coldest places – far colder than the poles. Ice would have naturally formed around these latitudes, including at the center of Sputnik Planitia.
New Horizons also saw strange ice formations resembling giant knife blades. This “bladed terrain” contains structures as tall as skyscrapers and made almost entirely of methane ice, likely formed as erosion wore away their surfaces, leaving dramatic crests and sharp divides. Similar structures can be found in high-altitude snowfields along Earth’s equator, though on a very different scale.
7. Polar Ice on Mars
This image, combining data from two instruments aboard our Mars Global Surveyor, depicts an orbital view of the north polar region of Mars. Credit: NASA/JPL-Caltech/MSSS
Mars has bright polar caps of ice easily visible from telescopes on Earth. A seasonal cover of carbon dioxide ice and snow advances and retreats over the poles during the Martian year, much like snow cover on Earth.
This animation shows a side-by-side comparison of CO2 ice at the north (left) and south (right) Martian poles over the course of a typical year (two Earth years). This simulation isn’t based on photos; instead, the data used to create it came from two infrared instruments capable of studying the poles even when they’re in complete darkness. This data were collected by our Mars Reconnaissance Orbiter, and Mars Global Surveyor. Credit: NASA/JPL-Caltech
During summertime in the planet’s north, the remaining northern polar cap is all water ice; the southern cap is water ice as well, but remains covered by a relatively thin layer of carbon dioxide ice even in summertime.
Scientists using radar data from our Mars Reconnaissance Orbiter found a record of the most recent Martian ice age in the planet’s north polar ice cap. Research indicates a glacial period ended there about 400,000 years ago. Understanding seasonal ice behavior on Mars helps scientists refine models of the Red Planet’s past and future climate.
8. Ice Feeds a Ring of Saturn
Wispy fingers of bright, icy material reach tens of thousands of kilometers outward from Saturn’s moon Enceladus into the E ring, while the moon’s active south polar jets continue to fire away. Credit: NASA/JPL/Space Science Institute
Saturn’s rings and many of its moons are composed of mostly water ice – and one of its moons is actually creating a ring. Enceladus, an icy Saturnian moon, is covered in “tiger stripes.” These long cracks at Enceladus’ South Pole are venting its liquid ocean into space and creating a cloud of fine ice particles over the moon’s South Pole. Those particles, in turn, form Saturn’s E ring, which spans from about 75,000 miles (120,000 kilometers) to about 260,000 miles (420,000 kilometers) above Saturn’s equator. Our Cassini spacecraft discovered this venting process and took high-resolution images of the system.
Jets of icy particles burst from Saturn’s moon Enceladus in this brief movie sequence of four images taken on Nov. 27, 2005. Credit: NASA/JPL/Space Science Institute
9. Ice Rafts on Europa
View of a small region of the thin, disrupted, ice crust in the Conamara region of Jupiter’s moon Europa showing the interplay of surface color with ice structures. Credit: NASA/JPL/University of Arizona
The icy surface of Jupiter’s moon Europa is crisscrossed by long fractures. During its flybys of Europa, our Galileo spacecraft observed icy domes and ridges, as well as disrupted terrain including crustal plates that are thought to have broken apart and “rafted” into new positions. An ocean with an estimated depth of 40 to 100 miles (60 to 150 kilometers) is believed to lie below that 10- to 15-mile-thick (15 to 25 km) shell of ice.
The rafts, strange pits and domes suggest that Europa’s surface ice could be slowly turning over due to heat from below. Our Europa Clipper mission, targeted to launch in 2022, will conduct detailed reconnaissance of Europa to see whether the icy moon could harbor conditions suitable for life.
10. Crater Ice on Our Moon
The image shows the distribution of surface ice at the Moon’s south pole (left) and north pole (right), detected by our Moon Mineralogy Mapper instrument. Credit: NASA
In the darkest and coldest parts of our Moon, scientists directly observed definitive evidence of water ice. These ice deposits are patchy and could be ancient. Most of the water ice lies inside the shadows of craters near the poles, where the warmest temperatures never reach above -250 degrees Fahrenheit. Because of the very small tilt of the Moon’s rotation axis, sunlight never reaches these regions.
A team of scientists used data from a our instrument on India’s Chandrayaan-1 spacecraft to identify specific signatures that definitively prove the water ice. The Moon Mineralogy Mapper not only picked up the reflective properties we’d expect from ice, but was able to directly measure the distinctive way its molecules absorb infrared light, so it can differentiate between liquid water or vapor and solid ice.
With enough ice sitting at the surface – within the top few millimeters – water would possibly be accessible as a resource for future expeditions to explore and even stay on the Moon, and potentially easier to access than the water detected beneath the Moon’s surface.
11. Bonus: Icy World Beyond Our Solar System!
With an estimated temperature of just 50K, OGLE-2005-BLG-390L b is the chilliest exoplanet yet discovered. Pictured here is an artist’s concept. Credit: NASA
OGLE-2005-BLG-390Lb, the icy exoplanet otherwise known as Hoth, orbits a star more than 20,000 light years away and close to the center of our Milky Way galaxy. It’s locked in the deepest of deep freezes, with a surface temperature estimated at minus 364 degrees Fahrenheit (minus 220 Celsius)!
One year ago, on Sept. 15, 2017, NASA’s Cassini spacecraft ended
its epic exploration of Saturn with a planned dive into the planet’s
atmosphere–sending back new science to the last second. The spacecraft is
gone, but the science continues. Here are 10 reasons why Cassini mattered…
Cassini and ESA (European Space Agency)’s Huygens probe expanded our understanding of the
kinds of worlds where life might exist.
2. A (Little) Like Home
At Saturn’s largest moon, Titan, Cassini and Huygens showed us one of the most Earth-like worlds we’ve
ever encountered, with weather, climate and geology that provide new ways to
understand our home planet.
3. A Time Machine (In a Sense)
Cassini gave us a portal to see the physical processes that likely
shaped the development of our solar system, as well as planetary systems around
4. The Long Run
The length of Cassini’s mission enabled us to observe weather and
seasonal changes over nearly half of a Saturn year, improving our understanding
of similar processes at Earth, and potentially those at planets around other
5. Big Science in Small Places
Cassini revealed Saturn’s moons to be unique worlds with their own
stories to tell.
Cassini showed us the complexity of Saturn’s rings and the
dramatic processes operating within them.
7. Pure Exploration
Some of Cassini’s best discoveries were serendipitous. What
Cassini found at Saturn prompted scientists to rethink their understanding of
the solar system.
8. The Right Tools for the Job
Cassini represented a staggering achievement of human and
technical complexity, finding innovative ways to use the spacecraft and its
instruments, and paving the way for future missions to explore our solar
9. Jewel of the Solar System
Cassini revealed the beauty of Saturn, its rings and moons,
inspiring our sense of wonder and enriching our sense of place in the cosmos.
Outstanding views Venus, Jupiter, Saturn and Mars with the naked eye!
You’ll have to look quickly after sunset to catch Venus. And through binoculars or a telescope, you’ll see Venus’s phase change dramatically during September – from nearly half phase to a larger thinner crescent!
Jupiter, Saturn and Mars continue their brilliant appearances this month. Look southwest after sunset.
Use the summer constellations help you trace the Milky Way.
Sagittarius: where stars and some brighter clumps appear as steam from the teapot.
Aquila: where the Eagle’s bright Star Altair, combined with Cygnus’s Deneb, and Lyra’s Vega mark the Summer Triangle.
Cassiopeia, the familiar “w”- shaped constellation completes the constellation trail through the Summer Milky Way. Binoculars will reveal double stars, clusters and nebulae.
Between September 12th and the 20th, watch the Moon pass from near Venus, above Jupiter, to the left of Saturn and finally above Mars!
Both Neptune and brighter Uranus can be spotted with some help from a telescope this month.
Look at about 1:00 a.m. local time or later in the southeastern sky. You can find Mercury just above Earth’s eastern horizon shortly before sunrise. Use the Moon as your guide on September 7 and 8th.
And although there are no major meteor showers in September, cometary dust appears in another late summer sight, the morning Zodiacal light. Try looking for it in the east on moonless mornings very close to sunrise. To learn more about the Zodiacal light, watch “What’s Up” from March 2018.
Our flying observatory SOFIA carries a telescope inside this Boeing 747SP aircraft. Scientists use SOFIA to study the universe — including stars, planets and black holes — while flying as high as 45,000 feet.
SOFIA is typically based at our Armstrong Flight Research Center in Palmdale, California, but recently arrived in Christchurch, New Zealand, to study celestial objects that are best observed from the Southern Hemisphere.
So what will we study from the land down under?
Eta Carinae, in the southern constellation Carina, is the most luminous stellar system within 10,000 light-years of Earth. It’s made of two massive stars that are shrouded in dust and gas from its previous eruptions and may one day explode as a supernova. We will analyze the dust and gas around it to learn how this violent system evolves.
Celestial Magnetic Fields
We can study magnetic fields in the center of our Milky Way galaxy from New Zealand because there the galaxy is high in the sky — where we can observe it for long periods of time. We know that this area has strong magnetic fields that affect the material spiraling into the black hole here and forming new stars. But we want to learn about their shape and strength to understand how magnetic fields affect the processes in our galactic center.
Saturn’s Moon Titan
Titan is Saturn’s largest moon and is the only moon in our solar system to have a thick atmosphere — it’s filled with a smog-like haze. It also has seasons, each lasting about seven Earth years. We want to learn if its atmosphere changes seasonally.
Titan will pass in front of a star in an eclipse-like event called an occultation. We’ll chase down the shadow it casts on Earth’s surface, and fly our airborne telescope directly in its center.
From there, we can determine the temperature, pressure and density of Titan’s atmosphere. Now that our Cassini Spacecraft has ended its mission, the only way we can continue to monitor its atmosphere is by studying these occultation events.
The Large Magellanic Cloud is a galaxy near our own, but it’s only visible from the Southern Hemisphere! Inside of it are areas filled with newly forming stars and the leftovers from a supernova explosion.
The Tarantula Nebula
The Tarantula Nebula, also called 30 Doradus, is located in the Large Magellanic Cloud and shown here in this image from Chandra, Hubble and Spitzer. It holds a cluster of thousands of stars forming simultaneously. Once the stars are born, their light and winds push out the material leftover from their parent clouds — potentially leaving nothing behind to create more new stars. We want to know if the material is still expanding and forming new stars, or if the star-formation process has stopped. So our team on SOFIA will make a map showing the speed and direction of the gas in the nebula to determine what’s happening inside it.
Also in the Large Magellanic Cloud is Supernova 1987A, the closest supernova explosion witnessed in almost 400 years. We will continue studying this supernova to better understand the material expanding out from it, which may become the building blocks of future stars and planets. Many of our telescopes have studied Supernova 1987A, including the Hubble Space Telescope and the Chandra X-ray Observatory, but our instruments on SOFIA are the only tools we can use to study the debris around it with infrared light, which let us better understand characteristics of the dust that cannot be measured using other wavelengths of light.
Jupiter and Venus at sunset, Mars, Saturn and Vesta until dawn.
First up is Venus. It reaches its highest sunset altitude for the year this month and sets more than two hours after sunset.
You can’t miss Jupiter, only a month after its opposition–when Earth was directly between Jupiter and the Sun.
The best time to observe Jupiter through a telescope is 10:30 p.m. at the beginning of the month and as soon as it’s dark by the end of the month.
Just aim your binoculars at the bright planet for a view including the four Galilean moons. Or just enjoy Jupiter with your unaided eye!
Saturn is at opposition June 27th, when it and the Sun are on opposite sides of Earth. It rises at sunset and sets at sunrise. Great Saturn viewing will last several more months. The best views this month will be just after midnight.
All year, the rings have been tilted wide open–almost 26 degrees wide this month–giving us a great view of Saturn’s distinctive rings.
The tilt offers us a view of the north polar region, so exquisitely imaged by the Cassini spacecraft.
Near Saturn, the brightest asteroid–Vesta–is so bright that it can be seen with your unaided eye. It will be visible for several months.
A detailed star chart will help you pick out the asteroid from the stars. The summer Milky way provides a glittery backdrop.
Finally, Mars grows dramatically in brightness and size this month and is visible by 10:30 p.m. by month end.
The best views are in the early morning hours. Earth’s closest approach with Mars is only a month away. It’s the closest Mars has been to us since 2003.
The Moon, Mars and Saturn and the Lyrid meteor shower!
The Moon, Mars and Saturn
The Moon, Mars and Saturn form a pretty triangle in early April, the Lyrid Meteors are visible in late April, peaking high overhead on the 22nd.
You won’t want to miss red Mars and golden Saturn in the south-southeast morning skies this month. Mars shines a little brighter than last month.
By the 7th, the Moon joins the pair. From a dark sky you may see some glow from the nearby Milky Way.
Midmonth, start looking for Lyrid meteors, which are active from April 14 through the 30th. They peak on the 22nd.
The Lyrids are one of the oldest known meteor showers and have been observed for 2,700 years. The first recorded sighting of a Lyrid meteor shower goes back to 687 BC by the Chinese. The pieces of space debris that interact with our atmosphere to create the Lyrids originate from comet C/1861 G1 Thatcher. Comet Thatcher was discovered on 5 April 1861 by A. E. Thatcher.
In the early morning sky, a patient observer will see up to more than a dozen meteors per hour in this medium-strength shower, with 18 meteors per hour calculated for the peak. U.S. observers should see good rates on the nights before and after this peak.
A bright first quarter moon plays havoc with sky conditions, marring most of the typically faint Lyrid meteors. But Lyra will be high overhead after the moon sets at midnight, so that’s the best time to look for Lyrids.
Jupiter & Juno
Jupiter will also be visible in the night sky this month!
Through a telescope, Jupiter’s clouds belts and zones are easy to see.
And watch the Great Red Spot transit–or cross–the visible (Earth-facing) disk of Jupiter every 8 hours.
Our Juno spacecraft continues to orbit this gas giant, too!
And Juno’s JunoCam citizen science team is creating exciting images of Jupiter’s features based on the latest spacecraft data.
Next month Jupiter is at opposition–when it rises at sunset, sets at sunrise, and offers great views for several months!
2—Four Hundred Elephants…The Saturn V rocket stood about the height of a 36-story-tall building, and 60 feet (18 meters) taller than the Statue of Liberty. Fully fueled for liftoff, the Saturn V weighed 6.2 million pounds (2.8 million kilograms), or the weight of about 400 elephants.Rockets We Love-Saturn V
Fifty years ago, with President Kennedy’s Moon landing deadline looming, the powerful Saturn V had to perform. And perform it did—hurling 24 humans to the Moon.
The race to land astronauts on the Moon was getting tense 50 years ago this week. Apollo 6, the final uncrewed test flight of America’s powerful Moon rocket, launched on April 4, 1968. Several technical issues made for a less-than-perfect launch, but the test flight nonetheless convinced NASA managers that the rocket was up to the task of carrying humans. Less than two years remained to achieve President John F. Kennedy’s goal to put humans on the Moon before the decade was out, meaning the Saturn V rocket had to perform.
1—“The only chance to get to the Moon before the end of 1969.”
After the April 1968 Apollo 6 test flight (pictured above), the words of Deke Slayton (one of the original Mercury 7 astronauts) and intense competition with a rival team in the Soviet Union propelled a 12-member panel to unanimously vote for a Christmas 1968 crewed mission to orbit the Moon.
2—Four Hundred Elephants…
The Saturn V rocket stood about the height of a 36-story-tall building, and 60 feet (18 meters) taller than the Statue of Liberty. Fully fueled for liftoff, the Saturn V weighed 6.2 million pounds (2.8 million kilograms), or the weight of about 400 elephants.
3—…and Busloads of Thrust
Stand back, Ms. Frizzle. The Saturn V generated 7.6 million pounds (34.5 million newtons) of thrust at launch, creating more power than 85 Hoover Dams. It could launch about 130 tons (118,000 kilograms) into Earth orbit. That’s about as much weight as 10 school buses. The Saturn V could launch about 50 tons (43,500 kilograms) to the Moon. That’s about the same as four school buses.
4—Christmas at the Moon
On Christmas Eve 1968, the Saturn V delivered on engineers’ promises by hurling Frank Borman, Jim Lovell and Bill Anders into lunar orbit. The trio became the first human beings to orbit another world. The Apollo 8 crew broadcast a special holiday greeting from lunar orbit and also snapped the iconic earthrise image of our home planet rising over the lunar landscape.
5—Gumdrop and Spider
The crew of Apollo 9 proved that they could pull the lunar module out of the top of the Saturn V’s third stage and maneuver it in space (in this case high above Earth). The crew named their command module “Gumdrop.” The Lunar Module was named “Spider.”
6—The Whole Enchilada
Saturn-V AS-505 provided the ride for the second dry run to the Moon in 1969. Tom Stafford, Gene Cernan and John Young rode Command Module “Charlie Brown” to lunar orbit and then took Lunar Module “Snoopy” on a test run in lunar orbit. Apollo 10 did everything but land on the Moon, setting the stage for the main event a few months later. Young and Cernan returned to walk on the Moon aboard Apollo 16 and 17 respectively. Cernan, who died in 2017, was the last human being (so far) to set foot on the Moon.
7—The Main Event
The launch of Apollo 11—the first mission to land humans on the Moon—provided another iconic visual as Saturn-V AS-506 roared to life on Launch Pad 39A at Kennedy Space Center in Florida. Three days later, Neil Armstrong and Buzz Aldrin made the first of many bootprints in the lunar dust (supported from orbit by Michael Collins).
Saturn V rockets carried 24 humans to the Moon, and 12 of them walked on its surface between 1969 and 1972. Thirteen are still alive today. The youngest, all in their early 80s, are moonwalkers Charles Duke (Apollo 16) and Harrison Schmitt (Apollo 17) and Command Module Pilot Ken Mattingly (Apollo 16, and also one of the heroes who helped rescue Apollo 13). There is no single image of all the humans who have visited the Moon.
This was the last launch of a Saturn V, but you can still see the three remaining giant rockets at the visitor centers at Johnson Space Center in Texas and Kennedy Space Center in Florida and at the United States Space and Rocket Center in Alabama (near Marshall Space Flight Center, one of the birthplaces of the Saturn V).
10—The Next Generation
The Saturn V was retired in 1973. Work is now underway on a fleet of rockets. We are planning an uncrewed flight test of Space Launch System (SLS) rocket to travel beyond the Moon called Exploration Mission-1 (EM-1). “This is a mission that truly will do what hasn’t been done and learn what isn’t known,” said Mike Sarafin, EM-1 mission manager at NASA Headquarters in Washington.
Read the web version of this 10 Things to Know article HERE.