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Would it be possible to slightly change the trajectory of Ceres to make it end up orbiting the Earth without messing up the Solar System? How much energy would be required and how long would the process take?
It's not possible to "slightly" change it's orbit unless you have a very very long time to wait. When Orbits get in synch with large bodies like Jupiter, for example, then Jupiter can give a tiny tug to Ceres each orbit and if positioned just right, it might nudge Ceres towards the inner solar-system, but only over millions, if not tens of millions of years. That's the slow way.
There's no fast way to move Ceres into an earth orbit without exerting a significant force on it. Orbits are largely stable and to change an orbit that much would requires a serious amount of force.
My math isn't always right, but Ceres orbits the sun at 17.9 KM per S and the earth orbits the sun at about 30 KM/S - now, you might think you need to speed Ceres up, but actually the opposite, it needs to be slowed down to fall into a lower orbit and the amount it needs to be slowed down (My math would be long and clumsy), but the actual deceleration needed is about 1/2 of that velocity difference - so imagine how much energy you'd need to move an object nearly 1,000 KM from side to side, made of ice and rock, twice as dense as water (mass of about a billion billion tons) and you need to accelerate that (decelerate it) oh about 5-6 KM per second (20,000 Kilometers per hour).
Now, a lot of energy could be saved by dropping Ceres to a fly-by near mars and then doing a gravity assist, and then, using earth's gravity as well to help capture it into an orbit around the earth. Mars weighs about 700 times what Ceres weighs, so the effect on Mars would be pretty tiny (all bets are off for Mars' 2 tiny moons though). But at minimum, you still need to decelerate Ceres by about 3 KPS (10-11,000 KPH), and at a billion billion tons that's a ungodly amount of energy, unless you're willing to do it very very slowly, perhaps or by finding a fuel source on Ceres to generate some kind of thrust or moving it so that it's in proper synch with Jupiter so that it gets a small kick towards the sun every so often, (see Mercury/Jupiter resonance below)
I love ideas like this by the way. Ceres would be a nice source of water Though in an earth's orbit it would lose it's water over time to solar wind, so it would be a trade-off moving it closer. Might be better to leave it where it is.
As to your 2nd question, Ceres weighs about 1/80th the mass of the moon. It's not massive enough to "mess up" any planets in the solar system, though if it crashed into the earth for example, it would "mess up" life on the earth big time, but it wouldn't significantly change the earth's orbit. It would change the earth's orbit a little, but only a tiny bit.
Dwarf planet Ceres is an ocean world: study
Ceres is the largest object in the asteroid belt between Mars and Jupiter and has its own gravity
The dwarf planet Ceres—long believed to be a barren space rock—is an ocean world with reservoirs of sea water beneath its surface, the results of a major exploration mission showed Monday.
Ceres is the largest object in the asteroid belt between Mars and Jupiter, enabling the NASA Dawn spacecraft to capture high-resolution images of its surface.
Now a team of scientists from the United States and Europe have analysed images relayed from the orbiter, captured around 35 kilometres (22 miles) from the asteroid.
They focused on the 20-million-year-old Occator crater and determined that there is an "extensive reservoir" of brine beneath its surface.
Several studies published Monday in the journals Nature Astronomy, Nature Geoscience and Nature Communications also shed further light on the dwarf planet, which was discovered by Italian polymath Giuseppe Piazzi in 1801.
Using infrared imaging, one team discovered the presence of the compound hydrohalite—a material common in sea ice but which until now had never been observed off of Earth.
Maria Cristina De Sanctis, from Rome's Istituto Nazionale di Astrofisica said hydrohalite was a clear sign Ceres' used to have sea water.
"We can now say that Ceres is a sort of ocean world, as are some of Saturn's and Jupiter's moons," she told AFP.
The team said the salt deposits looked like they had built up within the last two million years—the blink of an eye in space time.
This suggests that the brine may still be ascending from the planet's interior, something De Sanctis said could have profound implications in future studies.
"The material found on Ceres is extremely important in terms of astrobiology," she said.
"We know that these minerals are all essential for the emergence of life."
Writing in an accompanying comment article, Julie Castillo-Rogez, from the California Institute of Technology's Jet Propulsion Laboratory, said the discovery of hydrohalite was a "smoking gun" for ongoing water activity.
"That material is unstable on Ceres' surface, and hence must have been emplaced very recently," she said.
In a separate paper, US-based researchers analysed images of the Occator crater and found that its mounds and hills may have formed when water ejected by the impact of a meteor froze on the surface.
The authors said their findings showed that such water freezing processes "extend beyond Earth and Mars, and have been active on Ceres in the geologically recent past".
A. Nathues et al. Recent cryovolcanic activity at Occator crater on Ceres, Nature Astronomy (2020). DOI: 10.1038/s41550-020-1146-8
R. S. Park et al. Evidence of non-uniform crust of Ceres from Dawn's high-resolution gravity data, Nature Astronomy (2020). DOI: 10.1038/s41550-020-1019-1
M. C. De Sanctis et al. Fresh emplacement of hydrated sodium chloride on Ceres from ascending salty fluids, Nature Astronomy (2020). DOI: 10.1038/s41550-020-1138-8
B. E. Schmidt et al. Post-impact cryo-hydrologic formation of small mounds and hills in Ceres's Occator crater, Nature Geoscience (2020). DOI: 10.1038/s41561-020-0581-6
Dawn Gets Right in Between the Sun and Ceres and Takes this Video
The Dawn probe continues to excite and amaze! Since it achieved orbit around Ceres in March of 2015, it has been sending back an impressive stream of data and images on the protoplanet. In addition to capturing pictures of the mysterious “bright spots” on Ceres’ surface, it has also revealed evidence of cryovolcanism and the possibility of an interior ocean that could even support life.
Most recently, the Dawn probe conducted observations of the protoplanet while it was at opposition – directly between the Sun and Ceres surface – on April 29th. From this position, the craft was able to capture pictures of the Occator Crater, which contains the brightest spot on Ceres. These images were then stitched together by members of the mission team in order to create a short movie that showcases the view Dawn had of the planet.
The images were snapped when the Dawn probe was at an altitude of about 20,000 km (12,000 mi) from Ceres’ surface. As you can see (by clicking on the image below), the short movie shows the protoplanet rotating so that the Occator Crater is featured prominently. This crater is unmistakable thanks to the way its bright spots (two side by side white dots) stand out from the bland, grey landscape.
This increase in brightness is attributable to the size of grains of material on the surface, as well as their degree of porosity. As scientists have known for some time (thanks to the Dawn mission data) these bright spots are salt deposits, which stand out because they are more reflective than their surrounding environment. But for the sake of movie, this contrast was enhanced further in order to highlight the difference.
The observations were conducted as part of the latest phase of the Dawn mission, where it is recording cosmic rays in order to refine its earlier measurements of Ceres’ underground environment. In order to conduct these readings, the probe has been placed through an intricate set of maneuvers designed to shift its orbit around Ceres. Towards the end of April, this placed the probe in a position directly between the Sun and Ceres.
Based on previous data collected by ground-based telescopes and spacecraft that have viewed planetary bodies at opposition, the Dawn team predicted that Ceres would appear brighter from this vantage point. But rather than simply providing for some beautiful images of Ceres’ surface, the pictures are expected to reveal new details of the surface that are not discernible by visual inspection.
For more than two years now, the Dawn probe has been observing Ceres from a range of illumination angles that exceed those made of just about any other body in the Solar System. These has provided scientists with the opportunity to gain new insights into its surface features, properties, and the forces which shape it. Such observations will come in very handy as they continue to probe Ceres’ surface for hints of what lies beneath.
For years, scientists have been of the opinion that Ceres’ harbors an interior ocean that could support life. In fact, the Dawn probe has already gathered spectral data that hinted at the presence of organic molecules on the surface, which were reasoned to have been kicked up when a meteor impacted the surface. Characterizing the surface and subsurface environments will help determine if this astronomical body really could support life.
At present, the Dawn probe is maintaining an elliptical orbit that is taking it farther away from Ceres. As of May 11th, NASA reported that the probe was in good health and functioning well, despite the malfunction that took place in April where it’s third reaction wheel failed. The Dawn mission has already been extended, and it is expected to operate around Ceres until 2017.
Here are some specific topics that we think are important to understand. These pages go into more detail than the FAQ and glossary pages and will hopefully give you a more in-depth explanation of how certain things work.
Astrophotography might be thought of as a completely safe hobby, but as with anything you can't be complacent about it. There are a couple of things which can put you in danger, including imaging from remote areas with potentially dangerous conditions, or observing the Sun. This may seem obvious but it's important to make sure you're properly prepared for dealing with present dangers.
Stacking is slightly different between deep sky and planetary. We'll attempt to give a brief summary here and explain in more depth on a separate page.
In planetary stacking we capture a short video using a webcam at a high framerate. This allows us to overcome seeing issues and atmospheric turbulence (to an extent), and also increases our signal to noise ratio. We can stack the best parts of the best frames from the videos and apply wavelet sharpening to them to bring out fine details which otherwise would be invisible.
DSO stacking is a method of increasing the signal to noise ratio through the combination of images. To stack DSOs we must take very long exposures (anywhere from 60 seconds to 60 minutes) as they are very dim. A single frame has the same level of signal as a stacked frame, however the noise is drastically different. If you compare a single frame to a combined frame the background will be far less noisy and the image will look 'smoother' and allow you to stretch the histogram further and pull out more detail. To reduce the noise further we can use dark frames and bias frames. Capturing DSOs also introduces vignetting so flat frames are useful too.
Light pollution is an important consideration while imaging. It may not be avoidable but less light pollution can improve your images greatly. If you live near a dark site it's 100% worth driving there to image instead of from your backyard in town. It makes a huge amount of difference on the quality of the images you can capture. That said, many of our members image from cities or towns and are able to produce great results so if you don't have the ability to be portable don't let that discourage you.
Polar alignment can be confusing to astrophotographers new and old. Why should we polar align? How do we polar align? Our polar alignment guide will take you through the basics along with several methods of doing so.
CCDs vs Mono cams vs DSLRs
Thanks to /u/evwark and /u/orangelantern for writing this useful guide to the benefits and drawbacks of CCDs vs DSLR's and Mono imaging cams.
Filters for Astrophotography
Thanks to /u/yawg6669 for writing this guide on filters and their usage in the context of both DSLR and Mono imaging.
We encourage you to review equipment, especially obscure items. If the reviews are good they'll go into the reviews page.
“Ongoing activity in Occator brings additional and independent evidence for a deep brine layer and upgrades Ceres to the realm of ocean worlds,” writes Dawn’s project scientist Julie Castillo-Rogez (JPL). Her perspective commentary accompanies the seven articles appearing in various Nature journals.
She notes, though, that the underground ocean on Ceres is not like those harbored by the outer solar system's other ocean worlds, such as Jupiter’s moon Europa and Saturn’s Enceladus. Ceres’ is more of a slurry, Castillo-Rogez explains: about 25–30% saltwater mixed with a high concentration of rocky particles. Moreover, the ocean and overlying crust appear to be interacting as the ocean gradually freezes. Perhaps Ceres provides us with an end-of-life view of an ocean world.
Whether such an ocean would be habitable is still an open question, but a fascinating one to consider. As Castillo-Rogez writes, that makes Occator's unique floor “an obvious target for a future mission.”
Capturing an Asteroid: How NASA Could Do It
NASA's bold plan to drag an asteroid into orbit around the moon may sound like science fiction, but it's achievable with current technology, experts say.
President Barack Obama's 2014 federal budget request, which will be unveiled today (April 10), likely includes about $100 million for NASA to jump-start an asteroid-capture mission, U.S. Senator Bill Nelson (D-FL) said last week.
The plan aims to place a roughly 23-foot-wide (7 meters) space rock into a stable lunar orbit, where astronauts could begin visiting it as soon as 2021 using NASA's Space Launch System rocket and Orion capsule, Nelson said.
While challenging, the mission is definitely doable, said Chris Lewicki, president and chief engineer of billionaire-backed asteroid-mining firm Planetary Resources. [NASA's Asteroid-Capture Plan (Video)]
"Return of a near-Earth asteroid of this size would require today&rsquos largest launch vehicles and today&rsquos most efficient propulsion systems in order to achieve the mission," Lewicki, who served as flight director for NASA's Spirit and Opportunity Mars rovers and surface mission manager for the agency's Phoenix Mars lander, wrote in a blog post Sunday (April 7).
"Even so, capturing and transporting a small asteroid should be a fairly straightforward affair," Lewicki added. "Mission cost and complexity are likely on par with missions like the [$2.5 billion] Curiosity Mars rover."
Spurring solar system exploration
NASA's idea is similar to one proposed last year by scientists based at Caltech's Keck Institute for Space Studies in Pasadena.
The Keck study estimated that a robotic spacecraft could drag a 23-foot near-Earth asteroid (NEA) &mdash which would likely weigh about 500 tons &mdash into a high lunar orbit for $2.6 billion. The returns on this initial investment are potentially huge, the researchers said.
"Experience gained via human expeditions to the small returned NEA would transfer directly to follow-on international expeditions beyond the Earth-moon system: to other near-Earth asteroids, [the Mars moons] Phobos and Deimos, Mars and potentially someday to the main asteroid belt," the Keck team wrote in a feasibility study of their plan.
The mission would also help develop asteroid-mining technology, advocates say, and advance scientists' understanding of how our solar system took shape more than 4.5 billion years ago.
Asteroids "probably represent samples of the earliest matter that was made available to form our solar system and our Earth," Caltech's Paul Dimotakis, a member of the Keck study team, told SPACE.com in February.
"We learned a lot about the moon by analyzing the moon rocks that Apollo astronauts brought back," he added. [NASA's 17 Apollo Moon Missions in Pictures]
A challenging mission
Unmanned probes have successfully rendezvoused with asteroids in deep space multiple times. Japan's Hayabusa craft even snagged pieces of the near-Earth asteroid Itokawa in 2005, sending them back to our planet for study.
But bagging an entire asteroid and dragging it to our neck of the cosmic woods is unprecedented, and it presents several daunting challenges.
For example, the target asteroid will be spinning, which doesn't make for a smooth ride to lunar orbit. After the spacecraft captures the asteroid and brings it into a hold of sorts, the space rock will have to be de-spun, likely with thrusters, Dimotakis said.
"You might use reaction jets to take out most of it [the spin]," he said. "You would give you yourself a lot of time to do this, because there's no second chance in any of this."
Further, bringing the asteroid onboard greatly increases the spacecraft's mass, making propulsion and navigation much more difficult. And precise navigation will definitely be required to deliver the space rock to its desired orbit, Dimotakis said (though he also stressed that any asteroid chosen would pose no danger to humanity even if it somehow struck our planet).
But ion thrusters like the ones powering NASA's Dawn mission to the huge asteroid Vesta and dwarf planet Ceres should be muscular enough to make the journey, likely taking a few years to reach the asteroid and somewhat longer to come back. And the asteroid-laden probe could probably still be guided with great care, he added.
"My guess is that all of these are not insurmountable challenges, and you would be able to calibrate yourself after you snagged it and adjust your controls," Dimotakis said.
Choosing a target
Perhaps the biggest challenge of the entire mission is picking a suitable space rock to retrieve, Lewicki wrote in his blog post.
The Keck study recommends going after a carbonaceous asteroid packed full of water and other volatiles. Carbonaceous asteroids can be very dark, and it's tough to spot and characterize a 23-foot asteroid in the vast depths of space whatever its color.
So both Lewicki and Dimotakis stressed the importance of searching for potential asteroid targets sooner rather than later. Planetary Resources plans to begin launching a line of small prospecting space telescopes in 2014 or 2015, and these "Arkyd-100" craft could aid NASA's mission, Lewicki wrote.
Dimotakis, for his part, is engaged in a follow-up to the Keck study that's looking for potential targets in observations made by current telescopes.
"We are developing software in collaboration with JPL [NASA's Jet Propulsion Laboratory] that is going to exploit the observational digital record and essentially flag things that could be of interest and might be in this class," he said. "This has never happened before."
Still, mission scientists and engineers shouldn't just sit on their hands until an asteroid selection is made, he added.
It's important "to start developing the spacecraft before you even know where you're going," Dimotakis said. "If you do these things in parallel, then the mission timeline shrinks."
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2020 September 1
Salt Water Remnants on Ceres
Video Credit: Dawn Mission, NASA, JPL-Caltech, UCLA, MPS/DLR/IDA
Explanation: Does Ceres have underground pockets of water? Ceres, the largest asteroid in the asteroid belt, was thought to be composed of rock and ice. At the same time, Ceres was known to have unusual bright spots on its surface. These bright spots were clearly imaged during Dawn's exciting approach in 2015. Analyses of Dawn images and spectra indicated that the bright spots arise from the residue of highly-reflective salt water that used to exist on Ceres' surface but evaporated. Recent analysis indicates that some of this water may have originated from deep inside the dwarf planet, indicating Ceres to be a kindred spirit with several Solar System moons, also thought to harbor deep water pockets. The featured video shows in false-color pink the bright evaporated brine named Cerealia Facula in Occator Crater. In 2018, the mission-successful but fuel-depleted Dawn spacecraft was placed in a distant parking orbit, keeping it away from the Ceres' surface for at least 20 years to avoid interfering with any life that might there exist.
Log file including all camera and capture parameters
#1 Installation & Troubleshooting
#2 First Steps
#3 Layout & GUI
#4 Telescope & Autoguider
#5 Filterwheel & Focuser
#6 Capture Tools
It was back in 2008 when I got hold of a SONY newsletter announcing a new CCD sensor (ICX618) which promised fantastic sensitivity. Still working with an old webcam those days I instantly had the idea of replacing the webcam sensor with the new SONY sensor. It took weeks and dozens of emails to get the confidential spec of the new sensor. When I saw the sensitivity values it was clear: I had to have this sensor! The Basler Scout scA640 was the first machine vision camera on the market using this sensor and when I bought it the nightmare began: the included software was useless for planetary imaging and running the camera with the VRecord webcam tool was a complete PITA. Bugged by the inability to store even the basic camera settings I decided developing my own capture software.
What started as a solely private project soon turned into higher gear when fellow astronomers saw the software and insisted on getting it. I decided to make it public, included new camera interfaces and after years of continuous development FireCapture has evolved to one of the leading planetary capture tools. Developing the thing is only one part of the story: with a supportive community of users behind me I always had the feeling of someone 'looking over my shoulder' during the countless hours of programming. I can't mention all but just want to say:
Capturing Ceres - Astronomy
FVAS Astronomy Software CCD Control and Imaging Software
- CCD Control and Imaging Software:
This will be the longest list as there are many of these types of programs available. I will keep the descriptions short for this list.
CCDSoft - works in concert with TheSky for full camera and telescope control. Also provides the necessary image reduction, processing and stacking
MaxImDL - a popular choice that offers CCD control and processing
SharpCap - an easy-to-use but powerful Astronomy camera capture tool.
Sequence Generator Pro - image capture suite for astrophotography.
Nebulosity - capture and processing software for Mac/PC. Supports a bunch of Canon DSLRs and astro cams.
FireCapture - Simple image capturing software that re-sizes video resolution automatically & has auto align & dark frame reduction features
AstroArt 3.0 - 96bit image processing software
BackyardEOS/Nikon is software tailor made to control your DSLR camera. It is purposely built with astro-photography in mind.
PixInsight is an advanced image processing platform specialized in astrophotography and other technical imaging fields.
Astrotortilla - calibrate your GoTo tracking mount, GoTo any target with arcsecond accuracy and measure your polar alignment error
RegiStax - free image stacking program, used mostly for planets
DeepSkyStacker is a freeware for astrophotographers that simplifies all the pre-processing steps of deep sky pictures.
The Dwarf Planet Ceres Has a Dark Secret
You thought those bright spots on dwarf planet Ceres were cool? That was only the half of it. Ceres is also covered in dark spots, craters that—because of their position—never see the light of day. Now, astronomers have discovered that at least one and perhaps many of these shadowy regions are filled with water ice.
Ceres’ bright spots have captivated imaginations for more than a year, ever since NASA’s Dawn spacecraft began approaching the dwarf planet in the spring of 2015. Initially, scientists suspected the bright spots were made of ice, but the first good spectral data from Dawn revealed otherwise. The bright spots are actually giant piles of salt , dashing our hopes that Ceres might one day serve as an interplanetary gas station.
But now, evidence has emerged that water ice could be widespread on the surface of Ceres, after all. It’s just been hiding from us, according to Norbert Schorghofer of the University of Hawaii, who presented his research on Ceres’ “persistently shadowed regions” in a talk at the American Geophysical Union Conference this morning. The research, which was led by Thomas Platz of the Max Planck Institute, also appears today in Nature Astronomy.
“There are over 600 persistently shadowed regions on Ceres,” Schorghofer said, noting that these shadowlands are mostly associated with craters near the dwarf planet’s poles. “I call it Ceres’ darkest secret.”
Because persistently shadowed regions, by definition, get no sunlight, they’re considered “cold traps,” meaning they suck ice and water vapor in and keep it locked away forever. That is exactly what has happened in at least one dark crater near Ceres’ north pole.
During its flyovers of the north pole, the Dawn’s Framing Camera was able to capture enough scattered light from this crater—unimaginatively called PSR2, though I prefer Narnia—to “see” inside of it. What it saw was a giant sheet of water ice.
So far, PSR2 is the only dark spot which we’ve been able to peer into, but there could be others like it. “We assume other bright deposits in shadowed regions are water ice as well,” Schorghofer said. Other planets like Mercury feature water ice in virtually every cold trap on their surface.
Where the ice on the surface of Ceres originated is still a matter of debate, although the dark spots may be connected to the bright spots. Scientists suspect that the salt heaps found in craters like Occator (shown in the video above) were excavated from a subsurface brine layer during ancient impacts. Initially, those impacts would have brought a mix of water and ice to the surface. It’s possible that over time water escaped the bright spots, bounced around the planet, and eventually got sucked into Ceres’ cold traps.
It’s no surprise that Ceres’ dazzling bright spots captured our attention during the Dawn mission. But never let anyone say they’re the only cool thing about Ceres. After all, as soon as humans start traveling beyond Earth’s orbit, water is going to become the most precious resource in the solar system.