Yesterday, the European Space Agency (ESA) announced that another space program has been impacted by the Russia’s invasion of Ukraine:
Regarding the ExoMars programme continuation, the sanctions and the wider context make a launch in 2022 very unlikely. ESA’s Director General will analyse all the options and prepare a formal decision on the way forward by ESA Member States.
The ESA website on the Exomars program notes that it is a two part mission searching for life on Mars: the Trace Gas Orbiter launched in 2016 and the Exomars rover and surface platform planned for launch in 2022. NASA also contributed to this latest mission:
NASA’s participation in the 2022 ExoMars Rover mission includes providing critical elements to the premier astrobiology instrument on the rover, the Mars Organic Molecule Analyzer (MOMA). By studying organic molecules, the chemical building blocks of life, MOMA is designed to help answer questions about whether life ever existed on Mars, along with its potential origin, evolution and distribution on the Red Planet.
The list of impacted space missions will only grow.
Source/Credit: International Space Station (ISS) from NASA.
“If you block cooperation with us, who will save the ISS from uncontrolled deorbiting and falling on US or European territory?”
–Dmitry Olegovich Rogozin, Director General of Roscosmos, commenting on US sanctions against Russia’s aerospace industry resulting from that country’s invasion of Ukraine this week. The ISS is expected to stay aloft until 2031, assuming everyone cooperates.
The giant star…is waging a tug-of-war between gravity and radiation to avoid self-destruction. The star, called AG Carinae, is surrounded by an expanding shell of gas and dust — a nebula — that is shaped by the powerful winds of the star. The nebula is about five light-years wide, which equals the distance from here to our nearest star, Alpha Centauri.
The huge structure was created from one or more giant eruptions several thousand years ago. The star’s outer layers were blown into space, the expelled material amounting to roughly 10 times the mass of our Sun. These outbursts are typical in the life of a rare breed of star called a Luminous Blue Variable (LBV), a brief unstable phase in the short life of an ultra-bright, glamorous star that lives fast and dies young. These stars are among the most massive and brightest stars known. They live for only a few million years, compared to the roughly 10-billion-year lifetime of our own Sun. AG Carinae is a few million years old and resides 20,000 light-years away inside our Milky Way galaxy. The star’s expected lifetime is between 5 million and 6 million years.
Source/Credit: A NASA composite image of Uranus taken from Voyager 2 and the Hubble Space Telescope.
In an earlier posting, I highlighted some scientific papers calling for a return to Neptune rather than Uranus, in part because of Neptune’s moon Triton. But what is the argument for a mission to Uranus? Below I highlight one of the papers submitted to the Planetary Science and Astrobiology Decadal Survey 2023-2032 arguing the merits of a NASA mission to Uranus.
The large moons of Uranus are possible ocean worlds that exhibit a variety of surface features, hinting at endogenic geologic activity in the recent past. These moons are rich in water ice, as well as carbon-bearing and likely nitrogen-bearing constituents, which represent some of the key components for life as we know it. However, our understanding of Uranus and its moons is severely limited by the absence of data collected by an orbiting spacecraft…
An orbiter would vastly improve our understanding of these possible ocean worlds and allow us to assess the nature of water and organics in the Uranian system, thereby improving our knowledge of these moons’ astrobiological potential. A Flagship mission to Uranus can be carried out with existing chemical propulsion technology by making use of a Jupiter gravity assist in the 2030 – 2034 timeframe, leading to a flight time of only ~11 years, arriving in the early to mid 2040’s (outlined in the Ice Giants Pre-Decadal Survey Mission Study Report: https://www.lpi.usra.edu/icegiants/mission_study/Full-Report.pdf).
The five large moons discussed in the paper are Miranda, Ariel, Umbriel, Titania, and Oberon. Titania and Oberon where the first to be discovered back in 1787, followed by the later discoveries of Ariel, Umbriel, and Miranda (in that order). Unlike the moons of other planets, the moons of Uranus are named after magical spirits in English literature.
All of these ocean worlds have gained greater interest as we learn about the dynamics of life on of our own planet. As noted in an article in the MIT Technology Review:
It was once thought the solar system was probably a barren wasteland apart from Earth. Rocky neighbors were too dry and cold like Mars, or too hot and hellish like Venus. The other planets were gas giants, and life on those worlds or their satellite moons was basically inconceivable. Earth seemed to be a miracle of a miracle.
But life isn’t that simple. We now know that life on Earth is able to thrive in even the harshest, most brutal environments, in super cold and super dry conditions, depths of unimaginable pressures, and without the need to use sunlight as a source of energy. At the same time, our cursory understanding of these obscure worlds has expanded tremendously.
We have plenty of worlds to explore in our own solar system as other scientists continue their search for exoplanets and exomoons. The only question now is which local worlds will we visit in our next round of space missions.
Source/Credit: Voyager 2 image of Neptune and Triton from NASA/JPL-Caltech/Björn Jónsson.
In a recent posting, the non-profit Planetary Society is recommending NASA consider a return to Neptune and its moon Triton, noting that such a mission was part of the plan in the last Decadal Survey in 2010 along with trips to Mars and Europa (both of which are underway). NASA was aiming for Uranus or Neptune, but the Planetary Society stated a preference for Neptune.
The last and only visit to Neptune back in 1989 with NASA’s Voyager 2 spacecraft providing our first close view of the planet. The Voyager 2 mission also led to the discovery of six new moons as well as four rings around the planet. Moreover, the mission detected what may be underground oceans on the moon Triton.
The Planetary Society believes Triton, most likely a captured object from the Kuiper Belt, should be the deciding factor for visiting Neptune rather than Uranus. A 2019 paper, “The NASA Roadmap to Ocean Worlds,” highlights the value of visiting Triton to learn more about its potential oceans:
Triton is deemed the highest priority target to address as part of an Ocean Worlds Program. This priority is given based on the extraordinary hints of activity shown by the Voyager spacecraft (e.g., plume activity; smooth, walled plains units; the cantaloupe terrain suggestive of convection)…and the potential for ocean-driven activity given by Cassini results at Enceladus. Although the source of energy for Triton’s activity remains unclear, all active bodies in the Solar System are driven by endogenic heat sources, and Triton’s activity coupled with the young surface age makes investigation of an endogenic source important. Further, many Triton mission architectures would simultaneously address Ice Giant goals on which high priority was placed in the Visions and Voyages Decadal Survey. Finally, as Triton likely represents a captured Kuiper Belt object (KBO), some types of comparative planetology with KBOs could also be addressed in a Triton mission. Before the next Decadal Survey, a mission study should be performed that would address Triton as a potential ocean world; such a study could be part of a larger Neptune orbiter mission. The Decadal Survey should place high priority on Triton as a target in the Ocean Worlds Program.
The next Decadal Survey is being prepared now and among the papers submitted for consideration is this one highlighted by the Planetary Society – “Neptune and Triton: A Flagship for Everyone.” This paper states that a large strategic mission, called a “Flagship Mission,” to Neptune and Triton would have may benefits:
A Flagship Mission to Neptune and Triton would provide many firsts, an orbiter and atmospheric probe would not only be feasible on a Flagship budget, but achievable given the current state of the technology required by such a venture. This bold mission of exploration would be the first to orbit an ice giant to study the planet, its rings, small satellites, space environment, and the planetsized moon, Triton, itself a captured dwarf planet from the Kuiper Belt and a geophysically reactivated twin of Pluto. Broadly, the mission would address the following questions: How do theinteriors and atmospheres of ice giant (exo)planets form and evolve? What causes Neptune’s strange magnetic field, and how do its magnetosphere and aurora work? What are the origins of and connections between Neptune’s rings, arcs, and small moons? Is Triton an ocean world? What causes its plumes? What is the nature of its atmosphere? and how can Triton’s geophysics and composition expand our knowledge of dwarf planets like Pluto?
It sounds like a strong argument to me. I imagine the other 500 or so papers submitted as part of the upcoming Decadal Survey have some other great scientific missions in mind as well. I look forward to seeing the final recommendations to NASA.
Our Awesome Universe 