Voyager 2 is Still Talking to Us

Posted on by onespaceman2000
Image (Credit): Artist’s rendering of Voyager 2. (NASA)

After two weeks with no word, Voyager 2 is back to communicating with us as it continues its journey beyond our solar system. The whole incident started when NASA sent a bad command, but all is well.

Voyager 2 first left Earth back in August 1977 and exited the solar system in December 2018. Like Voyager 1, which is also outside the solar system now, Voyager 2 had the initial task of studying the planets. Voyager 2 focused on Jupiter, Saturn, Uranus and Neptune. It has shown it was capable of much more as it dragged the human race to the bleeding edge of space.

You can read all about Voyager 2’s accomplishments at this NASA site, including:

  • Voyager 2 is the only spacecraft to study all four of the solar system’s giant planets at close range.
  • Voyager 2 discovered a 14th moon at Jupiter.
  • Voyager 2 was the first human-made object to fly past Uranus.
  • At Uranus, Voyager 2 discovered 10 new moons and two new rings.
  • Voyager 2 was the first human-made object to fly by Neptune.
  • At Neptune, Voyager 2 discovered five moons, four rings, and a “Great Dark Spot.”

An impressive list of accomplishments, and the spacecraft is still ticking as it goes into the great unknown.

We need to keep these achievements in mind as we battle over this year’s NASA budget. We also need to remember that there was supposed to be four Voyager-like spacecraft rather than two, but budget cuts nixed the second set. Meaning we can still get some great things done even if we don’t have the budget to fund every piece of a grand vision.

More JWST Priorities

Posted on by onespaceman2000
Image (Credit): This diagram shows Lucy’s orbital path in green after her October 2021 launch to visit the Trojan asteroids. (Southwest Research Institute)

Last week I noted some of the mission priorities in the James Webb Space Telescope’s (JWST) first year. Those priorities were listed under “Exoplanets and Disks.” I thought I would highlight a few more, this time from the “Solar System Astronomy” list. Here are five more priorities:

  • Pluto’s Climate System with JWST;
  • The Moons of Uranus: A NIRSpec Investigation of Their Origins, Organic Constituents, and Possible Ocean World Activity;
  • A Pure Parallel Survey of Water in the Asteroid Belt;
  • DiSCo-TNOs: Discovering the Composition of the Trans-Neptunian Objects, Icy Embryos for Planet Formation; and
  • JWST Observations of Lucy Mission Targets.

Each of these priorities come with an explanation of the mission. For example, here is a little more about NASA’s Lucy mission from the JWST proposal:

The Lucy spacecraft – to be launched at approximately the same time as JWST – will perform the first ever in situ exploration of the Jupiter Trojan asteroids. Trojans are the largest population of solar system bodies currently unvisited by spacecraft, and revealing their composition and formation history is the key to untangling disparate hypothesis for the early dynamical evolution of the entire solar system.

Understanding these enigmatic bodies requires not just the high spatial resolution imagery and spectroscopy that will be afforded by Lucy, but also the superb near- and mid-infrared spectroscopy of which JWST is uniquely capable. The high signal-to-noise, high spectral resolution, and extended wavelength coverage beyond the capabilities of Lucy will allow JWST to sensitively probe the organic, carbonate, and silicate components of the surfaces of the Trojans. Meanwhile, the Lucy spectra and images will place these observations into their geological and historical context, greatly extending the scientific utility of both the JWST observations and the Lucy visit. Together these observations will paint a rich picture of this population, allowing us to trace connections with other bodies studied remotely and in situ across the solar system.

Lucy was launched last October and is expected to encounter its first Trojan asteroid until August 2027. You can find the full mission timeline here.

Television: More Space Stories This Summer

Posted on by onespaceman2000
Image (Credit): The eight plants of our solar system. (NOVA)

If you are looking for space series beyond the Moon, PBS has a few more shows for you. With the James Webb Space Telescope releasing the first photos next week, now is the time to brush up on the mission with a NOVA special. And check out the earlier NOVA piece on the planets as well. Dates and times may vary by region.

NOVA: Ultimate Space Telescope, July 13 at 9pm (28 minutes):

How did NASA engineers build and launch the most ambitious telescope of all time? Follow the dramatic story of the James Webb Space Telescope—the most complex machine ever launched into space. If it works, scientists believe that this new eye on the universe will peer deeper back in time and space than ever before to the birth of galaxies, and may even be able to “sniff” the atmospheres of exoplanets as we search for signs of life beyond Earth. But getting it to work is no easy task. The telescope is far bigger than its predecessor, the famous Hubble Space Telescope, and it needs to make its observations a million miles away from Earth—so there will be no chance to go out and fix it. That means there’s no room for error; the most ambitious telescope ever built needs to work perfectly. Meet the engineers making it happen and join them on their high stakes journey to uncover new secrets of the universe.

NOVA: The Planets, July 7 & 14 at 8pm (5 episodes)

Among the stars in the night sky wander the eight-plus worlds of our own solar system—each home to truly awe-inspiring sights. Volcanoes three times higher than Everest, geysers erupting with icy plumes, cyclones larger than Earth lasting hundreds of years. Each of our celestial neighbors has a distinct personality and a unique story. In this five-part series, NOVA will explore the awesome beauty of “The Planets,” including Saturn’s 175,000-mile-wide rings, Mars’ ancient waterfalls four times the size of any found on Earth, and Neptune’s winds—12 times stronger than any hurricane felt on our planet. Using unique special effects and extraordinary footage captured by orbiters, landers and rovers, we’ll treat viewers to an up-close look at these faraway worlds. We’ll stand on the dark side of Pluto, lit only by the reflected light of its moons, watch the sun set over an ancient Martian waterfall, and witness a storm twice the size of Earth from high above Saturn. And, we’ll reveal how each of them has affected our own planet: Earth. 

A Day in Astronomy: The Discovery of Uranus

Posted on by onespaceman2000
Source/Credit: Image of Uranus taken by Voyager 2 in 1986 (NASA).

On this day in 1781, astronomer Frederick William Herschel noticed a new object in the constellation of Gemini. With further study, he found he had discovered a new planet in our solar system – Uranus. Following his discovery, King George III appointed him Court Astronomer (yes, that King George who did not get many kind words from the embattled colonists on the other side of the pond).

While Frederick William Herschel is credited with numerous astronomical findings (including finding a number of moons, such as Saturn’s Enceladus, and discovering infrared radiation), he was also an accomplished musician. He played the oboe, violin, harpsichord and organ, and composed 24 symphonies as well as concertos, sonatas, and more. You can hear one of his symphonies here.

He was also a man with strong views about life beyond the Earth, including believing the Moon and the planets were populated with intelligent life (stating the surface of the Moon was similar to the English countryside) and speculating that the interior of the sun was heavy populated. Of course, he was a bit off the mark, but I expect he would be fascinated with the discovery of other planets and moons around the galaxy.

Extra: Frederick William Herschel’s sister Caroline assisted him with his work and also became an astronomer herself. For instance, she discovered a companion galaxy to the Andromeda Galaxy, M110 (NGC 205). She also discovered 14 nebulae and 8 comets. For her work cataloging stars, she was awarded the Gold Medal of the Royal Astronomical Society. She also became an Honorary Member of the Royal Astronomical Society in 1835.

Should We Return to Uranus?

Posted on by onespaceman2000
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 paper, “The Science Case for Spacecraft Exploration of the Uranian Satellites,” states:

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.