This illustration shows what exoplanet K2-18 b could look like based on science data. NASA’s James Webb Space Telescope examined the exoplanet and revealed the presence of carbon-bearing molecules. The abundance of methane and carbon dioxide, and shortage of ammonia, support the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18 b. But more extensive observations with the JWST are needed to understand its atmosphere with greater confidence. Image Credit: By Illustration: NASA, ESA, CSA, Joseph Olmsted (STScI)Science: Nikku Madhusudhan (IoA)
In the search for potentially life-supporting exoplanets, liquid water is the key indicator. Life on Earth requires liquid water, and scientists strongly believe the same is true elsewhere. But from a great distance, it’s difficult to tell what worlds have oceans of water. Some of them can have lava oceans instead, and getting the two confused is a barrier to understanding exoplanets, water, and habitability more clearly.
This image of Ceres was taken by NASA's Dawn spacecraft on May 7, 2015, from a distance of 8,400 miles (13,600 kilometers). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
When Sicilian astronomer Giuseppe Piazzi spotted Ceres in 1801, he thought it was a planet. Astronomers didn’t know about asteroids at that time. Now we know there’s an enormous quantity of them, primarily residing in the main asteroid belt between Mars and Jupiter.
Ceres is about 1,000 km in diameter and accounts for a third of the mass in the main asteroid belt. It dwarfs most of the other bodies in the belt. Now we know that it’s a planet—albeit a dwarf one—even though its neighbours are mostly asteroids.
But what’s a dwarf planet doing in the asteroid belt?
Venus' thick clouds mean that only radar imaging can reveal surface details. Image Credit: NASA/JPL-Caltech
The tantalizing possibility that life exists in the clouds of Venus is once again causing a stir amongst planetary scientists this week. Researchers out of the Massachusetts Institute of Technology, Cardiff University, and the University of Cambridge have proposed that some longstanding ‘anomalies’ in the composition of Venus’ atmosphere might be explained by the presence of ammonia. But ammonia itself would be a strange compound to discover there, unless some unknown process – such as biological life – was actively producing it. Perhaps more intriguingly, ammonia can remove the acidity from Venus’ hostile cloud-tops, suggesting that an airborne, ammonia-producing microbe might have evolved the ability to turn its hostile surroundings into something habitable.
One advantage to planetary science is that insights from one planet could explain phenomena on another. We understand Venus’ greenhouse gas effect from our own experience on the Earth, and Jupiter and Saturn share some characteristics. But Jupiter also provides insight into other, farther out systems, such as Uranus and Neptune. Now, a discovery from a spacecraft orbiting Jupiter might have solved a long-standing mystery about Uranus and Neptune – where has all the ammonia gone?
The moons of Saturn, from left to right: Mimas, Enceladus, Tethys, Dione, Rhea; Titan in the background; Iapetus (top) and irregularly shaped Hyperion (bottom). Some small moons are also shown. All to scale. Credit: NASA/JPL/Space Science Institute
Continuing with our “Definitive Guide to Terraforming“, Universe Today is happy to present our guide to terraforming Saturn’s Moons. Beyond the inner Solar System and the Jovian Moons, Saturn has numerous satellites that could be transformed. But should they be?
Around the distant gas giant Saturn lies a system of rings and moons that is unrivaled in terms of beauty. Within this system, there is also enough resources that if humanity were to harness them – i.e. if the issues of transport and infrastructure could be addressed – we would be living in an age a post-scarcity. But on top of that, many of these moons might even be suited to terraforming, where they would be transformed to accommodate human settlers.
As with the case for terraforming Jupiter’s moons, or the terrestrial planets of Mars and Venus, doing so presents many advantages and challenges. At the same time, it presents many moral and ethical dilemmas. And between all of that, terraforming Saturn’s moons would require a massive commitment in time, energy and resources, not to mention reliance on some advanced technologies (some of which haven’t been invented yet).
If we really want to find life on other worlds, why do we keep looking for life based on carbon and water? Why don’t we look for the stuff that’s really different?
In the immortal words of Arthur C. Clarke, “Two possibilities exist: either we are alone in the Universe or we are not. Both are equally terrifying.”
I’m seeking venture capital for a Universal buffet chain, and I wondering if I need to include whatever the tentacle equivalent of forks is on my operating budget. If there isn’t any life, I’m going to need to stop watching so much science fiction and get on with helping humanity colonize space.
Currently, astrobiologists are hard at work searching for life, trying to answer this question. The SETI Institute is scanning radio signals from space, hoping to catch a message. Since humans use radio waves, maybe aliens will too. NASA is using the Curiosity Rover to search for evidence that liquid water existed on the surface of Mars long enough for life to get going. The general rule is if we find liquid water on Earth, we find life. Astronomers are preparing to study the atmospheres of extrasolar planets, looking for gasses that match what we have here on Earth.
Isn’t this just intellectually lazy? Do our scientists lack imagination? Aren’t they all supposed to watch Star Trek How do we know that life is going to look anything like the life we have on Earth? Oh, the hubris!
Who’s to say aliens will bother to communicate with radio waves, and will transcend this quaint transmission system and use beams of neutrinos instead. Or physics we haven’t even discovered yet? Perhaps they talk using microwaves and you can tell what the aliens are saying by how your face gets warmed up. And how do we know that life needs to depend on water and carbon? Why not silicon-based lifeforms, or beings which are pure energy? What about aliens that breathe pure molten boron and excrete seahorse dreams? Why don’t these scientists expand their search to include life as we don’t know it? Why are they so closed-minded?
In 1976, two Viking spacecraft landed on Mars. The image is of a model of the Viking lander, along with astronomer and pioneering astrobiologist Carl Sagan. Each lander was equipped with life detection experiments designed to detect life based on its metabolic activities. Credits: NASA/Jet Propulsion Laboratory, Caltech
The reality is they’re just being careful. A question this important requires good evidence. Consider the search for life on Mars. Back in the 1970s, the Viking Lander carried an experiment that would expose Martian soil to water and nutrients, and then try to detect out-gassing from microbes. The result of the experiment was inconclusive, and scientists still argue over the results today. If you’re going to answer a question like this, you want to be conclusive. Also, getting to Mars is pretty challenging to begin with. You probably don’t want to “half-axe” your science.
The current search for life is incremental and exhaustive. NASA’s Spirit and Opportunity searched for evidence that liquid water once existed on the surface of Mars. They found evidence of ancient water many times, in different locations. The fact that water once existed on the surface of Mars is established. Curiosity has extended this line of research, looking for evidence that water existed on the surface of Mars for long periods of time. Long enough that life could have thrived. Once again, the rover has turned up the evidence that scientists were hoping to see. Mars was once hospitable for life, for long periods of time. The next batch of missions will actually search for life, both on the surface of Mars and bringing back samples to Earth so we can study them here.
The search for life is slow and laborious because that’s how science works. You start with the assumption that since water is necessary for life on Earth, it makes sense to just check other water in the Solar System. It’s the low hanging fruit, then once you’ve exhausted all the easy options, you get really creative.
An illustration of a Titanic lake by Ron Miller. All rights reserved. Used with permission.
Scientists have gotten really creative about how and where they could search for life. Astrobiologists have considered other liquids that could be conducive for life. Instead of water, it’s possible that alternative forms of life could use liquid methane or ammonia as a solvent for its biological processes. In fact, this environment exists on the surface of Titan. But even if we did send a rover to Titan, how would we even know what to look for?
We understand how life works here, so we know what kinds of evidence to pursue. But kind of what evidence would be required to convince you there’s life as you don’t understand it? Really compelling evidence.
Go ahead and propose some alternative forms of life and how you think we’d go searching for it in the comments.
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Astronauts Barry WiImore (foreground) and Terry Virts re-entered the U.S. segment wearing protective masks on Jan. 14, 2015. Credit: NASA TV
Nearly twelve hours after the threat of a leak of toxic ammonia forced the crew into a middle of the night evacuation from the US side of the International Space Station this morning (Jan. 14) and a hatch closure, top level managers from the partner space agencies gave the all clear and allowed the astronauts and cosmonauts to reopen access to the American portion of the orbiting outpost.
The six person crew hailing from the US, Italy and Russia were allowed to open the sealed hatch to the U.S. segment later this afternoon after it was determined that the ammonia leak was quite fortunately a false alarm.
No ammonia leak was actually detected. But the crew and mission control had to shut down some non essential station systems on the US segment in the interim.
All the Expedition 42 crew members were safe and in good health and never in danger, reported NASA.
The station crews and mission control teams must constantly be prepared and train for the unexpected and how to deal with potential emergencies, such as today’s threat of a serious chemical leak.
After a thorough review of the situation by the International Space Station mission management team, the crew were given the OK by flight controllers to head back.
They returned inside at 3:05 p.m. EST. Taking no chances, they wore protective masks and sampled the cabin atmosphere and reported no indications of any ammonia.
Fears that a leak had been detected resulted from the sounding of an alarm at around 4 a.m. EST.
The alarm forced Expedition 42 station commander Barry Wilmore and Flight Engineer Terry Virts of NASA and Flight Engineer Samantha Cristoforetti of the European Space Agency to don protective gas masks and move quickly into the Russian segment, sealing the hatch behind them to the US segment.
Inside the Russian segment, they joined the remainder of Expedition 42, namely cosmonauts Aleksandr Samokutyayev, Yelena Serova, and Anton Shkaplerov from Russia, also living and working aboard the ISS and rounding out the crew of four men and two women.
The International Space Station as seen by the departing STS-134 crew aboard space shuttle Endeavour in May 2011. US segment on top in this view. Credit: NASA
“The alarm is part of the environmental systems software on the station designed to monitor the cabin’s atmosphere. At the same time, the station’s protection software shut down one of two redundant cooling loops (Thermal Control System Loop B),” NASA said in an update.
Ammonia is a toxic substance used as a coolant in the stations complex cooling system that is an essential requirement to continued operation of the station.
Ammonia is a gas at room temperature that is extremely dangerous to inhale or when it comes in contact with skin, eyes and internal organs.
Precautions must be taken if a leak is feared in a confined space such as the ISS. It has about the same habitable volume as a four bedroom house.
As a professional chemist, I’ve worked frequently with ammonia in research and development labs and manufacturing plants and know the dangers firsthand. It can cause severe burns and irritations and worse.
There have been prior ammonia leaks aboard the ISS facility that forced a partial evacuation similar to today’s incident.
The ISS has been continuously occupied by humans for 15 years.
In the case of a life threatening emergency, the crew can rapidly abandon the station aboard the two docked Russian Soyuz capsules. They hold three persons each and serve as lifeboats.
Fortunately, the perceived ammonia leak this morning was not real and apparently was caused by a false alarm.
“This morning’s alarm is suspected to have been caused by a transient error message in one of the station’s computer relay systems, called a multiplexer-demultiplexer. A subsequent action to turn that relay box off and back on cleared the error message and the relay box is reported by flight controllers to be in good operating condition,” according to a NASA statement.
“Meanwhile, flight controllers are continuing to analyze data in an effort to determine what triggered the alarm that set today’s actions in motion.”
“Work to reactivate cooling loop B on the station will continue throughout the night and into the day Thursday. The crew members are expected to resume a normal complement of research activities on Thursday as well.”
This view shows the US side of the ISS that was evacuated today, Jan. 14, 2015, by the crew due to possible ammonia leak. The SpaceX CRS-5 Dragon is attached to the Harmony module. Credit: NASA TV
Jupiter is like a jawbreaker. Dig down beneath the swirling clouds and you’ll pass through layer after layer of exotic forms of hydrogen. What’s down there, deep within Jupiter?
What’s inside Jupiter? Is it chameleons? Candy? Cake? Cheddar? Chemtrails? No one knows. No one can ever know.
Well, that’s not entirely true… or even remotely true. Jupiter is the largest planet in the Solar System and two and a half times the mass of the other planets combined. It’s a gas giant, like Saturn, Uranus, and Neptune. It’s almost 90% hydrogen and 10% helium, and then other trace materials, like methane, ammonia, water and some other stuff. What would be a gas on Earth behaves in very strange ways under Jupiter’s massive pressure and temperatures.
So what’s deep down inside Jupiter? What are the various layers and levels, and can I keep thinking of it like a jawbreaker? At the very center of Jupiter is its dense core. Astronomers aren’t sure if there’s a rocky region deep down inside. It’s actually possible that there’s twelve to forty five Earth masses of rocky material within the planet’s core. Now this could be rock, or hydrogen and helium under such enormous forces that it just acts that way. But you couldn’t stand on it. The temperatures are 35,000 degrees C. The pressures are incomprehensible.
Surrounding the core is a vast region made up of hydrogen. But it’s not a gas. The pressure and temperature transforms the hydrogen into an exotic form of liquid metallic hydrogen, similar to the liquid mercury you’d see in a thermometer. This metallic hydrogen region turns inside the planet, and acts like an electric dynamo. Similar to our planet’s own iron core, this gives the planet a powerful magnetic field.
The next level up is still liquid hydrogen, but the pressure’s lower, so it’s not metallic any more. And then above this is the planet’s atmosphere. The upper layers of Jupiter’s atmosphere is the only part we can see. Those bands on the planet are clouds of ammonia that rotate around the planet in alternating directions. The lighter color zones are colder ammonia ice upwelling from below. Here’s the exciting part. Astronomers aren’t sure what the darker regions are.
This animated gif shows Voyager 1’s approach to Jupiter during a period of over 60 Jupiter days in 1979. Credit: NASA.
Still think you want to descend into Jupiter, to try and walk on its rocky interior? NASA tried that. In order to protect Jupiter’s moons from contamination, NASA decided to crash the Galileo spacecraft into the planet at the end of its mission. It only got point two percent of the way down through Jupiter’s radius before it was completely destroyed.
Jupiter is a remarkably different world from our own. With all that gravity, normally lightweight hydrogen behaves in completely exotic ways. Hopefully in the future we’ll learn more about this amazing planet we share our Solar System with.
What do you think? Is there a rocky core deep down inside Jupiter?
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Spectacular photo of Comet ISON taken Nov. 15 from Charleston, Rhode Island, USA showing the recent outburst. Click to enlarge. Credit: Scott MacNeill
Comet ISON — that bright comet last year that broke up around Thanksgiving weekend — included two forms of nitrogen in its icy body, according to newly released observations from the Subaru Telescope.
Of the two types found, the discovery of isotope 15NH2 was the first time it’s ever been seen in a comet. Further, the observations from the Japanese team of astronomers show “there were two distinct reservoirs of nitrogen [in] the massive, dense cloud … from which our Solar System may have formed and evolved,” stated the National Astronomical Observatory of Japan.
Besides being pretty objects to look at, comets are considered valuable astronomical objects because they’re a sort of time capsule of conditions early in the universe. The “fresh” comets are believed to come from a vast area of icy bodies called the Oort Cloud, a spot that has been relatively untouched since the solar system formed about 4.6 billion years ago. Spying elements inside of comets can give clues as to what was present in our neighborhood when the sun and planets were just coming to be.
“Ammonia (NH3) is a particularly important molecule, because it is the most abundant nitrogen-bearing volatile (a substance that vaporizes) in cometary ice and one of the simplest molecules in an amino group (–NH2) closely related to life. This means that these different forms of nitrogen could link the components of interstellar space to life on Earth as we know it,” NAOJ stated.
You can read more details about the finding at the NAOJ website, or in Astrophysical Journal Letters.
Sceenshot of a satellite view from Google/Digital Globe of the destruction in Moore, Oklahoma after the May 20, 2013 tornado. Click image to have access to an interactive, zoomable version via NPR.
For all you Earth observation geeks out there, we have some good news — two Russian astronauts are going to install a camera on Friday (Dec. 27) that will beam live images of Earth back to your browser.
The UrtheCast camera is the headline task for Expedition 38 astronauts Oleg Kotov and Sergey Ryazanskiy to perform, on top of installing a foot restraint and doing some equipment swapouts. This spacewalk, by the way, is not related in any way to the two successful contingency ones earlier this week to replace a faulty pump on station.
The spacewalk is supposed to start at 8 a.m. EST (1 p.m. UTC) and will be carried live on NASA Television, which you can view in the media player above or at this alternate link. The spacewalk is scheduled for seven hours, but could be longer or shorter as events arise.
“Imagine you have a nearly live Google Earth, but it isn’t four-year-old data – you have data that is being refreshed all the time, with videos coming down over interesting areas where interesting events are going on, showing you what is changing, what is going on,” said George Tyc, the chief technology officer at UrtheCast, in an interview with Universe Today earlier this year.
“What we really hope to pull off is to change the paradigm, get the everyday person interacting and seeing the data coming down from space to see the Earth and how it is evolving over time in a way that isn’t available right now.”
NASA astronaut Mike Hopkins during his first spacewalk on Dec. 21, 2013 during Expedition 38. He tweeted the next day: “Wow . . . can’t believe that is me yesterday. Wish I could find the words to describe the experience, truly amazing.” Credit: NASA
It’s been a busy week for spacewalkers on station as Rick Mastracchio and Mike Hopkins successfully replaced a pump that shut down two weeks ago and crippled one of the station’s two cooling loops for regulating the temperature of systems on station. With that work completed Tuesday (Dec. 24), a NASA update today (Dec. 26) said systems are slowly coming back online.
“Early on Christmas Day, the heat exchangers for the Destiny laboratory, the Harmony and Tranquility nodes and the Japanese Kibo laboratory were reintegrated to enable experiments racks and other systems affected by the partial Cooling Loop A shutdown Dec. 11 to come back on line,” NASA stated.
“The Columbus laboratory heat exchanger will remain down until the European Space Agency, at its own request, conducts that module’s integration next week when personnel return from the holiday.”
