Advanced propulsion breakthroughs are near. Spacecraft have been stuck at slow chemical rocket speeds for years and weak ion drive for decades. However, speeds over one million miles per hour before 2050 are possible. There are surprising new innovations with technically feasible projects.
NASA Institute for Advanced Concepts (NIAC) is funding two high potential concepts. New ion drives could have ten times better in terms of ISP and power levels ten thousand times higher. Antimatter propulsion and multi-megawatt ion drives are being developed.
An artist's illustration of the Parker Solar Probe approaching the Sun. Image: NASA
NASA’s Parker Solar Probe is now the closest object to the Sun that we’ve ever sent into space. On Oct. 29, 2018, at about 1:04 p.m. EDT, NASA’s probe broke the old record for the close-to-Sun distance of 42.73 million km (26.55 million miles). That record was held by the German-American Helios 2 spacecraft in 1976. And the probe will keep getting closer to the Sun.
Europa and Io move across the face of Jupiter, with the Great Red Spot behind them. Image: NASA/JPL/Cassini, Kevin M. Gill
What would it be like to be onboard the Cassini orbiter as it made its way around Jupiter and Saturn and their moons? Pretty cool. Now a new video made from Cassini images pieces together parts of that stately journey.
MASCOT's path across the surface of asteroid Ryugu. The path was recreated using data from the robot and from the mother probe Hayabusa2. Hayabusa2's shadow is visible at the bottim right. Image Credit: DLR/JAXA
Jupiter's moon Ganymede, the largest moon in the Solar System, seen orbiting Jupiter, the largest planet in the Solar System. This image was taken by the Cassini spacecraft. Image Credit: NASA/JPL/University of Arizona
Ganymede was shaped by pronounced periods of tectonic activity in the past, according to a new paper. It’s no longer active and its surface is more-or-less frozen in place now. But this discovery opens the door to better planning for future missions to Jupiter’s other frozen moon Europa. Unlike Ganymede, Europa is still tectonically active, and understanding past geological activity on Ganymede helps us understand present-day Europa.
The Mobile Asteroid Surface Scout (MASCOT) snapped this photo of the asteroid Ryugu during descent. The little hopping robot completed its brief mission and successfully transmitted all of its data back to Hayabusa2. Image: German Aerospace Center (CLR).
Earlier this week asteroid Ryugu had a visitor. The Mobile Asteroid Surface Scout (MASCOT) landed on Ryugu on October 3rd after it was successfully deployed from the Japanese Hayabusa2 space probe. The little hopping robot’s visit was brief however, and it stopped functioning on Oct. 4th.
"The Goblin", or dwarf planet 2015 TG387 shown in comparison to our Solar System's other planets.
Image: Illustration by Roberto Molar Candanosa and Scott Sheppard, courtesy of Carnegie Institution for Science.
Astronomers have found a new dwarf planet way out beyond Pluto that never gets closer than 65 AUs to the Sun. It’s nicknamed “The Goblin” which is much more interesting than its science name, 2015 TG387. The Goblin’s orbit is consistent with the much-talked-about but yet-to-be-proven Planet 9.
Artist’s impression of the first interstellar asteroid/comet, "Oumuamua". This unique object was discovered on 19 October 2017 by the Pan-STARRS 1 telescope in Hawaii. Credit: ESO/M. Kornmesser
In all this time, the question of ‘Oumuamua’s origin has remained unanswered. Beyond theorizing that it came from the direction of the Lyra Constellation, possibly from the Vega system, there have been no definitive answers. Luckily, an international team led by researchers from the Max Planck Institute for Astronomy (MPIA) have tracked ‘Oumuamua and narrowed down its point of origin to four possible star systems.
A view along the solar system, using Cosmic Watch.
A view along the Solar System, using Cosmic Watch.
Watching the heavens on a nightly, or even casual basis? The web and modern technology has certainly altered the landscape of modern astronomy, (mostly) for the better. Once, we all huddled around cardboard planispheres, illuminated by red flashlights; now, it’s now a common sight to see illuminated smartphone apps accompanying telescopes at star parties, all waving skyward with virtual planetarium programs guiding users around the night sky.
Artist's concept of the hypothetical "Planet Nine." Could it have moons? Credit: NASA/JPL-Caltech/Robert Hurt
In January of 2016, astronomers Mike Brown and Konstantin Batygin published the first evidence that there might be another planet in our Solar System. Known as “Planet 9” (or “Planet X”, to those who contest the controversial 2006 Resolution by the IAU), this hypothetical body was believed to orbit at an extreme distance from our Sun, as evidenced by the fact that certain Trans-Neptunian Objects (TNOs) all seem to be pointing in the same direction.
Since that time, other lines of evidence have emerged that have bolstered the existence of Planet 9/Planet X. However, a team of researchers from CU Boulder recently proposed an alternative explanation. According to their research, it could be interactions between Kuiper Belt Objects (KBOs) themselves that might explain the strange dynamics of “detached objects” at the edge of the Solar System.
The researchers presented their findings at the 232nd meeting of the American Astronomical Society, which ran from June 3-7 in Denver, Colorado. The presentation took place on June 4th during a press conference titled “Minor Planets, Dwarf Planets & Exoplanets”. The research was led Jacob Fleisig, an undergraduate studying astrophysics at CU Boulder, and included Ann-Marie Madigan and Alexander Zderic – an assistant professor and a graduate student at CU Boulder, respectively.
Artist’s conception of Sedna, a dwarf planet in the Solar System that only gets within 76 astronomical units (AUs) of our Sun. Credit: NASA/JPL-Caltech
For the sake of their study, the team focused on icy bodies like Sedna, a minor planet that orbits the Sun at a distance ranging from 76 AU at perihelion to 936 AU at aphelion. Along with a handful of other objects at this distance, such as Eris, Sedna appears to be separated from the rest of the Solar System – something which astronomers have struggled to explain ever since it was discovered.
Sedna was also discovered by Michael Brown who, along with Chad Trujillo of the Gemini Observatory and David Rabinowitz of Yale University, spotted it on November 14th, 2003, while conducting a survey of the Kuiper Belt. In addition to orbiting our Sun with a period of over 11,000 years, this minor planet and other detached objects has a huge, elliptical orbit.
What’s more, this orbit does not take them Sedna or these other objects anywhere near to Neptune or any other gas giant. Unlike Pluto and other Trans-Neptunian Objects (TNOs), it is therefore a mystery how they achieved their current orbits. The possible existence of a as-yet-undiscovered planet (Planet 9/Planet X), which would be about 10 times the size of Earth, is one hypothetical explanation.
After years of searching for this planet and attempting to determine where its orbit would take it, astronomers have yet to find Planet 9/Planet X. However, as Prof. Madigan explained in a recent CU Boulder press release, there is another possible explanation for the gravitational weirdness going on out there:
“There are so many of these bodies out there. What does their collective gravity do? We can solve a lot of these problems by just taking into account that question… Once you get further away from Neptune, things don’t make any sense, which is really exciting.”
While Madigan and her team did not originally set out to find another explanation for the orbits of “detached objects”, they ended up pursuing the possibility thanks to Jacob Fleisig’s computer modelling. While developing simulations to explore the dynamics of the detached objects, he noticed something very interesting about the region of space they occupy.
Having calculated the orbits of icy objects beyond Neptune, Fleisig and the rest of the team noticed that different objects behave much like the different hands on a clock. Whereas asteroids move like the minute hand (relatively fast and in tandem), larger objects like Sedna move more slowly like the hour hand. Eventually, the hands intersect. As Fleisig explained:
“You see a pileup of the orbits of smaller objects to one side of the sun. These orbits crash into the bigger body, and what happens is those interactions will change its orbit from an oval shape to a more circular shape.”
What Fleisig’s computer model showed was that Sedna’s orbit goes from normal to detached as a result of those small-scale interactions. It also showed that the larger the detached object, the farther it gets away from the Sun – something which agrees with previous research and observations. In addition to explaining why Sedna and similar bodies behave the way they do, these findings may provide clues to another major event in Earth’s history.
Artistic rendition of the Chicxulub impactor striking ancient Earth, which is believed to have caused the Cretaceous–Paleogene extinction event. Credit: NASA
This would be what caused the extinction of the dinosaurs. Astronomers have understood for a long time that the dynamics of the outer Solar System often end up sending comets towards the inner Solar System on a predictable timescale. This is the result of icy objects interacting with each other, which causes their orbits to tighten and widen in a repeating cycle.
And while the team is not able to say that this pattern was responsible for the impact that caused the Cretaceous–Paleogene extinction event (which resulted in the extinction of the dinosaurs 66 million years ago), it is a fascinating possibility. In the meantime, the research has shown just how fascinating the outer Solar System is, and how much remains to be learned about it.
“The picture we draw of the outer solar system in textbooks may have to change,” said Madigan. “There’s a lot more stuff out there than we once thought, which is really cool.”
The research was made possible thanks to the support of the NASA Solar System Workings and the Rocky Mountain Advanced Computing Consortium Summit Supercomputer.
