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.)
Curiosity snaps selfie at Kimberley waypoint with towering Mount Sharp backdrop on April 27, 2014 (Sol 613). Inset shows MAHLI camera image of rovers mini-drill test operation on April 29, 2014 (Sol 615) into “Windjama” rock target at Mount Remarkable butte. MAHLI color photo mosaic assembled from raw images snapped on Sol 613, April 27, 2014. Credit: NASA/JPL/MSSS/Marco Di Lorenzo/Ken Kremer - kenkremer.com
The Curiosity rover looks like she’s concentrating hard on her tasks on Mars, and now you can zoom around and see what it would look like to be standing next to the rover in Gale Crater.
This new interactive image put together by panoramacist Andrew Bodrov from Estonia uses some of the latest imagery from Curiosity’s MAHLI camera, taken on Sol 610 (April 27, 2014 back on Earth) and additional images from the rover’s 34-millimeter Mast Camera to create the full panoramic scene. The mosaic, which stretches about 30,000 pixels width, includes 138 images taken on Sol 610. Bodrov used 138 images and it stretches about 30,000 pixels wide.
You may wonder how the rover took this picture of itself without the camera or the robotic arm showing up in the images. It’s done by combining multiple pictures taken with the MAHLI camera that is mounted at the end of the robotic arm. “Wrist” motions and turret rotations on the arm allowed MAHLI to acquire the images, and the arm was positioned out of the shot in the images or portions of images used in the mosaic.
This artist's concept of Jupiter's moon Ganymede, the largest moon in the solar system, illustrates the club sandwich model of its interior oceans. Credit: NASA/JPL
Moons with subsurface oceans are all the rage these days. There’s Europa, Titan, and just recently Enceladus joined the short list of moons that likely harbor large amounts of subsurface water.
Jupiter’s moon Ganymede – the largest moon in the solar system — has long been a member of this club. The idea of this moon having water deep within its surface first “surfaced” back in 1970, and in 2000 after the Galileo mission flew by Ganymede, data confirmed the moon’s ocean, and showing it extends to depths of hundreds of miles, with additional evidence of salty seas.
Now, a new study says that the configuration of this moon’s interior might be more like a club sandwich, according to Steve Vance of NASA’s Jet Propulsion Laboratory, who led the research.
“Ganymede’s ocean might be organized like a Dagwood sandwich,” Vance said in a NASA press release, with ice and oceans stacked up in several layers, as in the graphic above.
The results also support the idea that primitive life may have possibly arisen on this icy moon.
Ganymede is about to hide behind Jupiter. Credit: NASA, ESA, and E. Karkoschka (University of Arizona)
This layered look was actually proposed last year by Vance and his team, and this latest research is based on theoretical computer modeling, where areas previously thought to be layers and lumps of just rocks and ice in Ganymede’s interior are actually layers of ice, water and rock.
Usually, places where water and rock interact are ripe for the development of life, scientists say. For example, its possible life began on Earth in bubbling vents on our sea floor.
The model computed by Vance and his team gets complicated when the different forms of ice are taken into account, which can cause varying amounts of pressure. This can change the whole dynamics of the moon’s interior.
If the lightest ice is on top, then the saltiest liquid is heavy enough to sink to the bottom. As the oceans churn and cold plumes snake around, ice in the uppermost ocean layer form in the seawater. When ice forms, salts precipitate out. The heavier salts would thus fall downward, and the lighter ice, or snow, would float upward. This snow melts again before reaching the top of the ocean, possibly leaving slush in the middle of the moon sandwich.
And if the first layer on top of the rocky core is salty water, that’s even better.
“This is good news for Ganymede,” said Vance. “Its ocean is huge, with enormous pressures, so it was thought that dense ice had to form at the bottom of the ocean. When we added salts to our models, we came up with liquids dense enough to sink to the sea floor.”
You can read more about their modeling here, and the research appears in the journal Planetary and Space Science. We’ll add a link to the paper when it becomes available.
Now, live from space, it’s Earth all the time! A new experiment called the High Definition Earth Viewing (HDEV) was launched on April 18, 2014 in the “trunk” on the SpaceX Dragon spacecraft and has been set up outside the International Space Station. The set of four commercial HD video cameras and is now operational, after being installed on the External Payload Facility of the ESA Columbus module yesterday. The cameras and electronics are enclosed in a pressurized box to provide protection to the equipment from the harsh environment of space.
Please note that the screen will appear black when the ISS is in orbital night — which happens every 90 minutes and lasts about 40 minutes. There also has been some downtime off and on that I’ve noted while watching this morning. This may be due to some initial setup/operation issues, or some occurrences of loss of signal. UPDATE: NASA’s now provided additional info on what’s happening if you’re not seeing beautiful views of Earth at anytime during the live feed: Black Scenes = Night side of the Earth; Gray Scenes = Switching to the next camera, or the communications downlink from the ISS in not available at the moment.
Also, the live video feed from HDEV will occasionally be unavailable due to loss of Ku-band transmission from the International Space Station. If that happens, just check the site again later.
But, having live HD streaming views of Earth is pretty awesome – but it’s also nifty to note that this is part of a student project.
High school students helped design of some of the HDEV components through the High Schools United with NASA to Create Hardware (HUNCH) program. Student teams will also help operate the experiment.
This experiment is completely separate from the UrtheCast commercial cameras on the ISS.
The HDEV does not record video on board the ISS, but all video is transmitted to the ground in real time. See the graphic below that explains how the cameras cycle automatically.
Part of the experiment is to test out the camera and equipment and assess the hardware’s ability to survive and function for long periods in space.
A lovely view of the Sombrero Galaxy in Virgo. Taken remotely from Siding Spring Observatory, Australia during several nights in April. Credit and copyright: Ian Sharp.
Here’s a wonderful view of the Sombrero Galaxy (M104, NGC 4594) in Virgo. This multi-hour, deep exposure was taken remotely by astrophotographer Ian Sharp from the Siding Spring Observatory in Australia over the past few weeks, with 12 hours of Luminance and 5 hours each on R, G and B channels.
The Sombrero Galaxy is a spiral galaxy that we see edge-on from Earth. Its outer dust lanes and bright central bulge aare visible in this wonderful image. There’s a zoomed out version, below, and you can see more of Ian Sharp’s great imagery at his website.
A expanded view of M104, the Sombrero Galaxy and the surrounding region. Credit and copyright: Ian Sharp.
Here are the details of the equipment Ian Sharp used to take these images:
Optical Tube Assembly RCOS 12.5” F/9 (2857mm focal length) Carbon-Fibre Tube w/TCC2, PIR and FFC
Equatorial Mount Bisque Paramount ME
Imaging Camera Apogee F16M-D9 (KAF-16803) with 7 slot filter wheel
Imaging Camera Filters Astrodon Series II L,R,G,B, Ha (5nm), OIII (3nm) and SII (3nm)
Guide Camera MMOAG with SBIG ST-402ME
The system delivers a 44×44 arcmin FoV operating at .65 arcsec/pixel
Processed entirely in PixInsight.
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
Curiosity snaps selfie at Kimberley waypoint with towering Mount Sharp backdrop on April 27, 2014 (Sol 613). Inset shows MAHLI camera image of rovers mini-drill test operation on April 29, 2014 (Sol 615) into “Windjama” rock target at Mount Remarkable butte. MAHLI color photo mosaic assembled from raw images snapped on Sol 613, April 27, 2014. Credit: NASA/JPL/MSSS/Marco Di Lorenzo/Ken Kremer - kenkremer.com
Curiosity snaps selfie at Kimberley waypoint with towering Mount Sharp backdrop on April 27, 2014 (Sol 613). Inset shows MAHLI camera image of rovers mini-drill test operation on April 29, 2014 (Sol 615) into “Windjana” rock target at Mount Remarkable butte. MAHLI color photo mosaic assembled from raw images snapped on Sol 613, April 27, 2014. Credit: NASA/JPL/MSSS/Marco Di Lorenzo/Ken Kremer – kenkremer.com See more Curiosity photo mosaics below[/caption]
The answer has come Fast and Furious – “Drill, Baby, Drill !”
After spending the weekend inspecting an enticing slab of sandstone rock at “Kimberley”, the team directed NASA’s Curiosity rover to bore a test hole into a Martian rock target called “Windjana” on Tuesday, April 29, Sol 615, that exhibited interesting bumpy textures. See above our illustrative “Kimberley” photo mosaic.
“A decision about full drilling is planned in coming days,” NASA JPL press officer Guy Webster told me today.
Hazcam fisheye camera image shows Curiosity drilling into “Windjana” rock target on April 29, 2014 (Sol 615). Flattened and colorized image shows Mount Remarkable butte backdrop. Credit: NASA/JPL/Marco Di Lorenzo/Ken Kremer – kenkremer.com
Engineers commanded Curiosity to perform the so called “mini-drill” operation at “Windjana”- as the site of the robots third drilling operation since touching down on the Red Planet back in August 2012.
The 1 ton robot drilled a test hole 0.63 inch (1.6 centimeters) in diameter and to a depth of about 0.8 inch (2 centimeters) using the hammering drill at the terminus of the robotic arm.
Windjana is an outcrop of sandstone located at the base of a Martian butte named Mount Remarkable at “The “Kimberley” waypoint – a science stopping point reached by the rover in early April 2014 along its epic trek to towering Mount Sharp, the primary destination of the mission.
See our photo mosaics illustrating Curiosity’s science activities and drilling operations on “Windjana” and roving around the “Mount Remarkable” butte at “The Kimberley Waypoint” – above and below – by the image processing team of Marco Di Lorenzo and Ken Kremer.
Multisol composite photo mosaic shows deployment of Curiosity’s rovers robotic arm and APXS X-ray spectrometer onto the ‘Winjana’ rock target at Mount Remarkable for evaluation as missions third drill target inside Gale Crater on Mars. The colorized navcam raw images were stitched together from several Martian days up to Sol 612, April 26, 2014. Credit: NASA/JPL-Caltech/Ken Kremer – kenkremer.com/Marco Di Lorenzo
The team is evaluating the resulting hole and powdery, gray colored tailings with the arm’s high resolution MAHLI camera and other instruments to determine whether to follow up with a deep drilling operation to a depth of 2.5 inches (6.4 centimeters).
To prepare for the “mini drill” operation, Curiosity first brushed the candidate drill site off with the wire-bristle Dust Removal Tool (DRT) this past weekend, to clear away obscuring Red Planet dirt and dust hindering observations with the cameras and spectrometers.
“In the brushed spot, we can see that the rock is fine-grained, its true color is much grayer than the surface dust, and some portions of the rock are harder than others, creating the interesting bumpy textures,” said Curiosity science team member Melissa Rice of the California Institute of Technology, Pasadena., in a NASA statement
“All of these traits reinforce our interest in drilling here in order understand the chemistry of the fluids that bound these grains together to form the rock.”
“Windjana,” is named after a gorge in Western Australia.
Curiosity’s Panoramic view of Mount Remarkable at ‘The Kimberley Waypoint’ where rover will conduct 3rd drilling campaign inside Gale Crater on Mars. The navcam raw images were taken on Sol 603, April 17, 2014, stitched and colorized. Credit: NASA/JPL-Caltech/Ken Kremer – kenkremer.com/Marco Di Lorenzo
Why was Kimberley chosen as a science destination ?
“The Kimberley” has interesting, complex stratigraphy,” Curiosity Principal Investigator John Grotzinger, of the California Institute of Technology, Pasadena, told me.
If the team decides that Windjana meets the required criteria, Curiosity will bore a full depth hole into the sandstone rock, and then pulverize and filter it prior to delivery to the two onboard miniaturized chemistry labs – SAM and CheMin.
Windjana would be the first sandstone drill target, if selected. The first two drill locations at ‘John Klein’ and ‘Cumberland’ inside Yellowknife Bay were mudstone.
Curiosity departed the ancient lakebed at the Yellowknife Bay region in July 2013 where she discovered a habitable zone with the key chemical elements and a chemical energy source that could have supported microbial life billions of years ago – and thereby accomplished the primary goal of the mission. Curiosity scans scientifically intriguing rock outcrops of gorgeous Martian terrain at ‘The Kimberley’ waypoint in search of next drilling location beside Mount Remarkable butte, at right. Mastcam color photo mosaic assembled from raw images snapped on Sol 590, April 4, 2014. Credit: NASA/JPL/MSSS/Marco Di Lorenzo/Ken Kremer – kenkremer.com
Stay tuned here for Ken’s continuing Curiosity, Opportunity, Chang’e-3, SpaceX, Orbital Sciences, LADEE, MAVEN, MOM, Mars and more planetary and human spaceflight news.
Ken Kremer Curiosity Mars rover captured this panoramic view of a butte called “Mount Remarkable” and surrounding outcrops at “The Kimberley ” waypoint on April 11, 2014, Sol 597. Colorized navcam photomosaic was stitched by Marco Di Lorenzo and Ken Kremer. Credit: NASA/JPL-Caltech/Marco Di Lorenzo/Ken Kremer – kenkremer.com
This artist's illustration shows the hypervelocity star cluster HVGC-1 escaping from the supergiant elliptical galaxy M87. HVGC-1 is the first runaway star cluster discovered by astronomers. It is fated to drift through intergalactic space.
David A. Aguilar (CfA)
We’ve discovered dozens of so-called “hypervelocity stars” — single stars that break the stellar speed limit. But today astronomers multiplied the number of these ‘runaway’ stars by hundreds of thousands. The Virgo Cluster galaxy, M87, has ejected an entire star cluster, throwing it toward us at more than two million miles per hour.
“Astronomers have found runaway stars before, but this is the first time we’ve found a runaway star cluster,” said lead author Nelson Caldwell of the Harvard-Smithsonian Center for Astrophysics, in a press release.
About one in a billion stars travel at a speed roughly three times greater than our Sun (which clocks in at 220 km/s with respect to the galactic center). At a speed that fast, these stars can easily escape the galaxy entirely, traveling rapidly throughout intergalactic space.
But this is the first time an entire star cluster has broken free.
What would cause an entire cluster — hundreds of thousands of stars packed together a million times more closely than in the neighborhood of our Sun — to reach such a tremendous speed?
Single hypervelocity stars have puzzled astronomers for years. But by observing their speed and direction, astronomers can trace these stars backward, finding that some began moving quickly in the Galactic Center. Here, an interaction with the supermassive black hole can kick a star away at an alarming speed. Another option is that a supernova explosion propelled a nearby star to a huge speed.
Caldwell and colleagues think M87 might have two supermassive black holes at its center. The star cluster wandered too close to the pair, which picked off many of the cluster’s outer stars while the inner core remained intact. The black holes then acted like a slingshot, flinging the cluster away at a tremendous speed.
The star cluster is moving so fast it should soon by sailing into intergalactic space. It may already be, but its distance remains unknown.
Velocities of stars, globular clusters and galaxies toward Virgo. HVGC-1 is the marked extreme left outlier. Image Credit: Caldwell et al.
The team found the globular cluster — dubbed HVGC-1 — with a stroke of luck. They had been analyzing 2,500 globular cluster candidates for years. While a computer algorithm automatically calculated the speed of every cluster, any oddity was analyzed by hand.
Over 1,000 candidates have measured velocities between 500 and 3000 km/s. These speeds are typical for Virgo Cluster members. But HVGC-1 has a radial velocity of -1026 km/s. “This is the most negative, bulk velocity ever measured for an astronomical object not orbiting another object,” writes Caldwell.
“We didn’t expect to find anything moving that fast,” said coauthor Jay Strader of Michigan State University.
Future measurements pinpointing the exact distance to the globular cluster will help shed light on its exact origins.
The paper will be published in The Astrophysics Journal Letters and is available for download here.
The NASA Z-2 suit will incorporate the "technology" design the public voted on. Credit: NASA
Striking a Buzz Lightyear-like pose above is the winning design for NASA’s Z-2 spacesuit prototype. The version, called “technology”, was by far the popular vote in an online contest the agency held to choose between three prototypes, garnering 62% of 233,431 votes.
While this will never be used in space, NASA said the next-generation prototype will be useful in helping design future spacesuits. And this prototype will go through a “test campaign” that includes vacuum tests, pool tests in NASA’s Neutral Buoyancy Laboratory and in an area at the Johnson Space Center that simulates the surface of Mars.
“With the agency laser focused on a path to Mars, work to develop the technologies astronauts one day will use to live and work on Mars has already begun. Each iteration of the Z-series will advance new technologies that one day will be used in a suit worn by the first humans to step foot on the Red Planet,” NASA stated.
To learn more about the suit and the differences from its predecessor, the Z-1, check out this recent Universe Today article.
Video released today by SpaceX confirms the landing legs deployed successfully on the Falcon 9’s first stage booster, paving the way for future vertical soft touchdowns on land. SpaceX’s next-generation Falcon 9 rocket was tested following the launch of the CRS-3 mission for the Dragon spacecraft, which launched from Cape Canaveral Air Force Station on April 18. This was the first test of the landing legs deployment with a re-entry burn and soft landing in the Atlantic Ocean.
The SpaceX CEO had mentioned the success during a post launch briefing and later tweeted further updates that the Falcon 9 first stage actually made a good water landing despite rough seas, with waves swelling at least six feet. He also spoke briefly of the success during a news conference at the National Press Club on April 25, saying video would be released soon.
The video above is actually a cleaned-up (repaired) version of the original. There are a short few frames which show the landing legs deployed just before splashdown, which Musk highlighted in a recent Tweet. Obviously this is not the greatest-quality video ever released, but exciting still the same. SpaceX is actually looking for help in cleaning up the video even further.
Artist's impression of Beta Pictoris b. Credit: ESO L. Calçada/N. Risinger (skysurvey.org)
Between the time you got to work this morning and the time you leave today — assuming an eight-hour work cycle — an entire day will have passed on Beta Pictoris b, according to new measurements of the exoplanet.
This daily cycle, mapped for the first time on a planet outside of the solar system, may reveal a link between how big a planet is and how fast it rotates, astronomers stated. That said, caution is needed because there are only a handful of planets where the rotation is known: the eight planets of our Solar System and Beta Pictoris b.
The planet’s day is shorter than any other planet in our Solar System, which at first blush makes sense because the planet is also larger than any other planet in our Solar System. Beta Pictoris b is estimated at 16 times larger and 3,000 times more massive than Earth. (For comparison, Jupiter is about 11 times larger and 318 times more massive than Earth.)
“It is not known why some planets spin fast and others more slowly,” stated says co-author Remco de Kok, “but this first measurement of an exoplanet’s rotation shows that the trend seen in the Solar System, where the more massive planets spin faster, also holds true for exoplanets. This must be some universal consequence of the way planets form.”
Planets in our Solar system size comparison. Largest to smallest are pictured left to right, top to bottom: Jupiter, Saturn, Uranus, Neptune, Earth, Venus, Mars, Mercury. Via Wikimedia Commons.
Astronomers mapped the planet’s equatorial rotation using the CRIRES instrument on the Very Large Telescope. What helped was not only the planet’s large size, but also its proximity to Earth: it’s about 63 light-years away, which is relatively close to us.
As the planet ages (it’s only 20 million years old right now) it is expected to shrink and spin more quickly, assuming no other external forces. The Earth’s rotation is slowed by the moon, for example.
The study (“Fast spin of a young extrasolar planet” will soon be up on Nature’s website and was led by Leiden University’s Ignas Snellen.
