Saturn's "UFO moon" Pan up close. Credit:
NASA/JPL/Space Science Institute
This new view of Saturn’s moon Pan is the closest yet, snapped by Cassini from a distance of 15,268 miles (24,572 km) on March 7, 2017. Pan measures 22 miles wide by 14 miles across and displays a number of small craters along with parallel ridges and grooves. Its broad, thinner equatorial ridge displays fine, parallel striations. Credit: NASA/JPL/Space Science Institute
Besides Earth, Saturn may be the only other planet where you can order rings with a side of ravioli. Closeup photos taken by the Cassini probe of the the planet’s second-innermost moon, Pan, on March 7 reveal remarkable new details that have us grasping at food analogies in a feeble attempt to describe its unique appearance.
A side view of Pan better shows its thin and wavy ridge likely built up through the accumulation of particles grabbed from Saturn’s rings. The ridge is between 0.9 and 2.5 miles (1-4 km) thick. Credit: NASA/JPL/Space Science Institute
As Pan moves along the Encke Gap its gravity creates ripples in Saturn’s A-ring. Credit: NASA/JPL/Space Science Institute
The two-part structure of the moon is immediately obvious: a core body with a thin, wavy ridge encircling its equator. How does such a bizarre object form in the first place? There’s good reason to believe that Pan was once part of a larger satellite that broke up near Saturn long ago. Much of the material flattened out to form Saturn’s rings while large shards like Pan and another ravioli lookalike, Atlas, orbited within or near the rings, sweeping up ring particles about their middles. Tellingly, the ridges are about as thick as the vertical distances each satellite travels in its orbit about the planet.
Pan casts its shadow on Saturn’s A-ring from within the 200-mile-wide (325 km) Encke Gap, which is maintained by the presence of the moon. Pan shares the gap with several diffuse ringlets from which it may still be gathering additional material around its equatorial ridge. Credit: NASA/JPL/Space Science Institute
Today, Pan orbits within and clears the narrow Encke Gap in Saturn’s outer A-ring of debris. It also helps create and shape the narrow ringlets that appear in the gap It’s lookalike cousin Atlas orbits just outside the A-ring.
Pan and Altas (25×22 miles) orbit within Saturn’s ring plane and may both be fragments from a larger moon breakup that created Saturn’s rings. Both have swept up material from the rings to form equatorial ridges. Credit: NASA/JPL/Space Science Institute
Moons embedded in rings can have profound effects on that material from clearing gaps to creating new temporary ringlets and raising vertical waves of material that rise above and below the ring plane. All these effects are produced by gravity, which gives even small objects like Pan dominion over surprisingly vast regions.
Enjoy this animated gif created from photos of the close flyby of Pan. Credit: NASA/JPL/Space Science Institute
A radar view of Venus taken by the Magellan spacecraft, with some gaps filled in by the Pioneer Venus orbiter. Credit: NASA/JPL
Venus is known as Earth’s Sister Planet. It’s roughly the same size and mass as Earth, it’s our closest planetary neighbor, and Venus and Earth grew up together.
When you grow up with something, and it’s always been there, you kind of take it for granted. As a species, we occasionally glance over at Venus and go “Huh. Look at Venus.” Mars, exotic exoplanets in distant solar systems, and the strange gas giants and their moons in our own Solar System attract much more of our attention.
If a distant civilization searched our Solar System for potentially habitable planets, using the same criteria we do, then Venus would be front page news for them. It’s on the edge of the habitable zone and it has an atmosphere. But we know better. Venus is a hellish world, hot enough to melt lead, with crushing atmospheric pressure and acid rain falling from the sky. Even so, Venus still holds secrets we need to reveal.
Chief among those secrets is, “Why did Venus develop so differently?
Conditions on Venus pose unique challenges. The history of Venus exploration is littered with melted Soviet Venera Landers. Orbital probes like Pioneer 12 and Magellan have had more success recently, but Venus’ dense atmosphere still limits their effectiveness. Advances in materials, and especially in electronic circuitry that can withstand Venus’ heat, have buoyed our hopes of exploring the surface of Venus in greater detail.
The group acknowledged several over-arching questions we have about Venus:
How can we understand the atmospheric formation, evolution, and climate history?
How can we determine the evolution of the surface and interior?
How can we understand the nature of interior-surface-atmosphere interactions over time, including whether liquid water was ever present?
Since the Vision 2050 Workshop is all about the next 50 years, Cutts and his team looked at the challenges posed by Venus’ unique conditions, and how they could answer questions in the near-term, mid-term, and long-term.
Near Term Exploration (Present to 2019)
Near-Term goals for the exploration of Venus include improved remote-sensing from orbital probes. This will tell us more about the gravity and topography of Venus. Improved radar imaging and infrared imaging will fill in more blanks. The team also promoted the idea of a sustained aerial platform, a deep probe, and a short duration lander. Multiple probes/dropsondes are also part of the plan.
Dropsondes are small devices that are released into the atmosphere to measure winds, temperature, and humidity. They’re used on Earth to understand the weather, and extreme phenomena like hurricanes, and can fulfill the same purpose at Venus.
Dropsondes are released into the atmosphere, and their descent is slowed by a small parachute. As they descend, they gather data on temperature, wind, and humidity. Image By Staff Sgt. Randy Redman of the US Air Force
In the near-term, missions whose final destination is not Venus can also answer questions. Fly-bys by craft such as Bepi-Colombo, Solar Probe Plus, and the Solar Orbiter missions can give us good information on their way to Mercury and the Sun respectively. These missions will launch in 2018.
Bepi-Colombo, a joint mission of the ESA and JAXA, will perform two fly-bys of Venus on its way to Mercury. Image: ESA/JAXA
The ESO’s Venus Express and Japan’s Akatsuki, (Venus Climate Orbiter), have studied Venus’ climate in detail, especially its chemistry and the interactions between the atmosphere and the surface. Venus Express ended in 2015, while Akatsuki is still there.
Mid-Term Exploration (2020-2024)
The mid-term goals are more ambitious. They include a long-term lander to study Venus’ geophysical properties, a short-duration tessera lander, and two balloons.
The tesserae lander would land in a type of terrain found on Venus known as tesserae. We think that at one time, Venus had liquid water on it. The fundamental evidence for this may lie in the tesserae regions, but the terrain is extremely rough. A short duration lander that could land and operate in the tesserae regions would help us answer Venus’ liquid water question.
Thanks to the continued development of heat-hardy electronics, a long-term duration lander (months or more) is becoming more feasible in the mid-term. Ideally, any long-term mobile lander would be able to travel tens to hundreds of kilometers, in order to acquire a regional sample of Venus’ surface. This is the only way to take geochemistry and mineralogy measurements at multiple sites.
On Mars the landers are solar-powered. Venus’ thick atmosphere makes that impossible. But the same dense atmosphere that prohibits solar power might offer another solution: a sail-powered rover. Old-fashioned sail power might hold the key to moving around on the surface of Venus. Because the atmosphere is so dense, only a small sail would be necessary.
A simple sail-powered rover may solve the problem of mobility on the Venusian surface. Image: NASA
Long-Term Exploration (2025 and Beyond)
The long-term goals from Cutts and his team are where things get really interesting. A long-lived surface rover is still on the list, or possibly a near-surface craft like a balloon. Also on there is a long-lived seismic network.
A seismic network would really start to reveal the secrets behind Venus’ geophysical life. Whereas a lander would give us estimates of seismic activity, they would be crude compared to what a network of seismic sensors would reveal about Venus’ inner workings. A more thorough understanding of quake mechanisms and locations would really get the theorists buzzing. But it’s the final thing on the list that would be the end-goal. A sample-return mission.
We’re getting good at in situ measurements on other worlds. But for Venus, and for all the other worlds we have visited or want to visit, a sample return is the holy grail. The Apollo missions brought back hundreds of kilograms of lunar samples. Other sample-return missions have been sent to Phobos, which failed, and to asteroids, with varying degrees of success.
Subjecting a sample to the kind of deep analysis that can only be done on labs here on Earth is the end-game. We can keep analyzing samples as we develop new technologies to examine them with. Science is iterative, after all.
An artist’s image of Hayabusa leaving Earth. Hayabusa was a Japanese sample return mission to the asteroid 25143 Itokawa. The mission was a partial success. A sample mission to Earth’s sister planet is the holy-grail for the exploration of Venus. Image credit: JAXA
The 2003 Planetary Science Decadal Survey identified the importance of a sample return mission to Venus’ atmosphere. A balloon would float aloft in the clouds, and an ascending rocket would launch a collected sample back to Earth. According to Cutts and his team, this kind of sample-return mission could act as a stepping stone to a surface sample mission.
A surface sample would likely be the pinnacle of achievement when it comes to understanding Venus. But like most of the proposed goals for Venus, we’ll have to wait awhile.
The Changing Future
Cutts and the team acknowledge that the technology to enable exploration of Venus is in flux. No more missions to Venus are planned before 2020. There’ve been proposals for things like sail powered landers, but we’re not there yet. We’re developing heat-resistant electronics, but so far they’re very simple. There’s a lot of work to do.
On the other hand, some things may happen sooner. It may turn out that we can learn about Venusian seismic activity from balloon-borne or orbital sensors. The team says that “Due to strong mechanical coupling between the atmosphere and ground, seismic waves are launched into the atmosphere, where they may be detected by infrasound on a balloon or infrared or ultraviolet signatures from orbit.” That’s thanks to Venus’ dense atmosphere. That means that the far-term goal of seismic sensing of the interior of Venus could be shifted to the near-term or mid-term.
Japan’s Akatsuki orbiter captured this image of a gravity wave in Venus’ upper cloud layer. Could orbiter sensors remove the need for a network of seismic sensors on the surface? Image credit: JAXA
As work on nanosatellites and cubesats continues, they may play a larger role at Venus, and shift the timelines. NASA wants to include these small satellites on every launch where there is a few kilograms of excess capacity. A group of these nanosatellites could form a network of seismic sensors much more easily and much sooner than an established network of surface sensors. A network of nanosatellites could also serve as a communications relay for other missions.
Venus doesn’t generate a lot of buzz these days. The discovery of Earth-like worlds in distant solar systems generates headline after headline. And the always popular search for life is centered on Mars, and the icy/sub-surface moons of our Solar System’s gas giants. But Venus is still a tantalizing target, and understanding Venus’ evolution will help us understand what we’re seeing in distant solar systems.
Astronomy Cast Ep. 443: Destroy and Rebuild Pt. 7: Tsunamis
Surf’s up! Today we’re going to be talking about one of the most devastating natural disasters out there: tsunamis. We’re talking huge waves that wreck the seashore. But it turns out, there many ways you can get a tsunami, and one of those has to do with space.
We usually record Astronomy Cast as a live Google+ Hangout on Air every Friday at 1:30 pm Pacific / 4:30 pm Eastern. You can watch here on Universe Today or from the Astronomy Cast Google+ page.
Special Guest:
Nic DiPalma is the Founder and CEO of SpacetimeLabs, a ‘creative agency’ for science – a team of award-winning designers, producers, and developers creating brands, communication strategies, and digital content for the science community. With 20 years’ experience as a creative director, designer, and entrepreneur in educational media, public television, broadcast/cable news, corporate brand strategy, and experience design for web and mobile products, Nic is helping scientists and researchers engage the public to inspire a deeper connection and greater support.
We use a tool called Trello to submit and vote on stories we would like to see covered each week, and then Fraser will be selecting the stories from there. Here is the link to the Trello WSH page (http://bit.ly/WSHVote), which you can see without logging in. If you’d like to vote, just create a login and help us decide what to cover!
If you would like to join the Weekly Space Hangout Crew, visit their site here and sign up. They’re a great team who can help you join our online discussions!
If you’d like to join Fraser and Paul Matt Sutter on their tour to Iceland in February, 2018, you can find the information at astrotouring.com.
If you would like to sign up for the AstronomyCast Solar Eclipse Escape, where you can meet Fraser and Pamela, plus WSH Crew and other fans, visit our site here and sign up!
We record the Weekly Space Hangout every Friday at 12:00 pm Pacific / 3:00 pm Eastern. You can watch us live on Universe Today, or the Universe Today YouTube page
Comet 2P Encke glides through Pisces on February 16th. Image credit and copyright: Hisayoshi Kato.
Comet 2P Encke glides through Pisces on February 16th. Image credit and copyright: Hisayoshi Kato.
Miss out on Comet 45/P Honda-Mrkos-Padadušáková last month? We’ll admit, it was fairly underwhelming in binoculars… but fear not, there are several other binocular comets in the pipeline for 2017.
Maybe you managed to catch sight of periodic Comet 2P Encke in late February after sunset before it disappeared into the Sun’s glare. Pronounced (En-Key), the comet actually passes through the field of view of the joint NASA/ESA Solar Heliospheric Observatory’s (SOHO) LASCO C3 camera from March 8th to March 14th before reemerging in the dawn sky.
I see you… Comet 2P Encke is now in SOHO’s LASCO C3 field of view, above Mercury (the bright object) moving in the opposite direction: pic.twitter.com/gcYwv0Sdkp
Northern hemisphere observers have already got a sneak peek at Encke’s performance low in the dusk in February as it heads towards perihelion. Now the comet heads southward, as it vaults up into the dawn sky for folks south of latitude 30 degrees north in mid-March. From latitude 30 degrees north, Encke will clear 15 degrees elevation above the southeastern horizon around March 31st. Viewers south of the equator will have a much better viewing prospect, as Encke glides southward through Aquarius. When will you first spot it?
The dawn path of 2P Encke through the first week of April as seen from latitude 30 degrees north. Credit: Starry Night.
Also: don’t forget to ‘spring forward’ to Daylight Saving Time this weekend for a majority of North America prior to beginning your dawn comet vigil… Europe and the United Kingdom gets a brief reprieve ’til March 26th.
Her are some upcoming key events for Comet 2P Encke:
Closest to Sun: March 10th, with a perihelion of 0.33 AU.
Closest to Earth: March 12th, at 0.65 AU distant.
Brightest: Around March 15. Encke is currently at magnitude +7, and should top out at magnitude +6, though it’ll only be 14 degrees from the Sun on this date.
This is Encke’s 63rd passage through the solar system since Pierre Méchain linked successive passages of the comet to the same in 1819. Like Edmond Halley, Encke didn’t discover the most famous of comets that now bears his name, but instead merely deduced its periodic nature. Halley was 1st, and Encke was second (hence the “2” in 2P…) The shortest short period comet, Encke was captured sometime thousands of years ago into its short period orbit, and is destined to burn out one day as it ventures from 4.1 to 0.33 AU from the Sun. Encke is also the source of the annual Taurid meteor shower in November, notable for producing a high rate of fireballs.
Comet 2P Encke on February 19th. Image credit and copyright: Cajun Astro.
Comets can be elusive beasties, as all of that precious quoted magnitude is smeared out over an extended surface area. Add on top this the fact that comets are also notorious for often under- and occasionally over-performing expectations. Just look at the ‘none more black’ albedo of comet 67P Churumov-Gerasimenkochronicled by ESA’s Rosetta spacecraft: it’s a miracle we can see ’em at all. And finally, that low contrast dawn sky can easily hide a faint binocular comet, fading it to invisibility. Start your comet vigil early, sweeping the horizon with binocs. An early start and a clear view are key. The slim waning crescent Moon sits 12 degrees north of Comet Encke on the morning of March 26th, and the comet also passes less than 3 degrees from the Helix Nebula (NGC 7293) on (no joke) April Fool’s Day April 1st.
The view on the morning of March 26th, 30 minutes before sunrise. Credit: Stellarium.
Flashback to one Encke orbit ago to 2013 and the comet provided a good dawn preshow to that biggest of cosmic let downs, Comet ISON. And although Encke makes its rounds every 3.3 years, orbital geometry assures that we won’t get another favorable viewing from Earth until 2036.
The orbit of 2P Encke. Credit NASA/JPL
Speaking of great comets that never were, we juuuust missed having a spectacular comet this past month, when recently discovered long-period Comet 2017 E1 Borisov passes just 0.045 AU (!) interior to our orbit. Unfortunately, this occurs five months too early, with the Earth almost exactly at the wrong place in its orbit. Now, if it was only August…
Comet Teaser for 2017
Yeah, the gambler’s fallacy would tell us that we’re due for the next great comet of the century, for sure. In the meantime, we’ve still got Comets 41P/Tuttle-Giacobini-Kresák (late March/April), C/2015 ER61 PanSTARRS (May), and C/2015 V2 Johnson (June) on tap as good binocular comets in 2017.
Be sure to enjoy elusive comet Encke as it flits once more though the dawn skies.
-Read about comets, occultations, eclipses and more for the year, in our new free e-book 101 Astronomical Events for 2017 out from Universe Today.
SpaceX conducts successful static hot fire test of Falcon 9 booster atop Launch Complex 39A at the Kennedy Space Center on Mar 9, 2017 as seen from Space View Park, Titusville, FL. Liftoff with EchoStar 23 comsat is planned for 14 March 2017. Credit: Ken Kremer/Kenkremer.com
SpaceX conducts successful static hot fire test of Falcon 9 booster atop Launch Complex 39A at the Kennedy Space Center on Mar 9, 2017 as seen from Space View Park, Titusville, FL. Liftoff with EchoStar 23 comsat is planned for 14 March 2017. Credit: Ken Kremer/Kenkremer.com
SPACE VIEW PARK/KENNEDY SPACE CENTER, FL – After a pair of back to back postponements presumably due to technical gremlins, the third time proved to be the charm at last as SpaceX engineers carried out a successful engine test of the Falcon 9 first stage this evening (Mar. 9) atop historic pad 39 at the Kennedy Space Center in Florida.
The brief test lasting about 3 seconds took place at 6 p.m. this evening, with an exciting eruption of smoke and ash into the air during the serene waning sunlight as I witnessed from Space View Park in Titusville, FL – which is a great place to watch launches from, offering an unobstructed view across the inland waterway.
Liftoff of the Falcon 9 carrying the EchoStar 23 telecommunications satellite is now slated for a post midnight spectacle next Tuesday, Mar. 14 from pad 39A at the opening of the launch window at 1:34 a.m. EDT.
The two and a half hour launch window closes at 4:04 a.m. EDT.
The delayed completion of the static fire test resulted in a two day launch slip from March 12 to March 14 in order to complete all the prelaunch processing.
SpaceX Falcon 9 rocket minus EchoStar 23 comsat stands erect atop Launch Complex 39-A at the Kennedy Space Center as seen from Playalinda Beach, Fl, prior to static fire test on 9 Mar. 2017. This is only the second rocket to stand on pad 39A since the retirement of NASA’s Space Shuttles in July 2011. Liftoff is slated for 14 Mar 2017. Credit: Ken Kremer/Kenkremer.com
“Following today’s static fire test, SpaceX is targeting the launch of the EchoStar XXIII satellite from Launch Complex 39A (LC-39A) at Kennedy Space Center in Florida on Tuesday, Mar. 14, SpaceX confirmed in a statement soon after completion of the test.
“SpaceX’s Falcon 9 rocket will deliver the satellite to a Geostationary Transfer Orbit (GTO).”
The EchoStar 23 launch counts as only the second Falcon 9 ever to blastoff from pad 39A- which SpaceX’s billionaire CEO Elon Musk leased from NASA back in April 2014.
The nighttime lunge to space should offer spectacular viewing. But unlike most recent SpaceX missions, this Falcon will be the last expendable first stage. It is not outfitted with landing legs or grid fins to maneuver it back to a touchdown.
Watch this video of the March 9 static fire test from colleague Jeff Seibert:
Video Caption: Falcon 9 static fire test on Pad 39A on March 9, 2017. This is the second Falcon 9 static fire test on Pad 39A in preparation for the launch of the EchoStar-23 satellite. Credit: Jeff Seibert
The planned Mar. 14 launch comes barely three weeks after the Falcon’s successful debut on Feb. 19 on the NASA contracted Dragon CRS-10 mission that delivered over 2.5 tons of cargo to the six person crew living and working aboard the International Space Station (ISS).
Launch Complex 39A was repurposed by SpaceX from launching Shuttles to Falcons. It had lain dormant for launches for nearly six years since Space Shuttle Atlantis launched on the final shuttle mission STS 135 in July 2011.
Historic maiden blastoff of SpaceX Falcon 9 rocket from Launch Complex 39A at the Kennedy Space Center) at 9:38 a.m. EDT on Feb 19, 2017, on Dragon CRS-10 resupply mission to the International Space Station (ISS) for NASA. Credit: Ken Kremer/kenkremer.com
Today’s engine test was carried out absent the expensive satellite payload bolted on top, to keep it safely stored away in case of a repeat of the catastrophic Falcon 9/Amos-6 pad explosion last September at pad 40 during a similar test that destroyed both the rocket and payload and caused extensive damage to the pad infrastructure.
If all goes well, the EchoStar 23 launch will showcase that SpaceX is picking up the pace of space launches and recovering from the Amos-6 disaster.
During today’s static fire test, the rocket’s first and second stages are fueled with liquid oxygen and RP-1 propellants like an actual launch and a simulated countdown is carried out to the point of a brief engine ignition.
The hot fire test generated a huge plume of smoke exhausting out the north side of the flame trench of Launch Complex 39A at approximately 6:00 p.m. EST, Mar. 9. at the opening of a 6 hour long test window.
The hold down engine test with the erected rocket involved the ignition of all nine Merlin 1D first stage engines generating some 1.7 million pounds of thrust at pad 39A – which has been repurposed from its days as a shuttle launch pad.
The Merlin 1D engines fired for about 3 seconds while the two stage rocket was restrained on the pad.
The smoke cloud soon dissipated and within 5 minutes there was barely a trace of what we shall soon see next Tuesday – if all goes well with launch processing and the ever changing sunshine state weather.
SpaceX conducts successful static hot fire test of Falcon 9 booster atop Launch Complex 39A at the Kennedy Space Center on Mar 9, 2017 as seen from Space View Park, Titusville, FL. Liftoff with EchoStar 23 comsat is planned for 14 March 2017. Credit: Ken Kremer/Kenkremer.com
Titusville offers a prime viewing location for anyone interested in traveling to the Florida Space Coast to see this Falcon 9 launch in person.
SpaceX Falcon 9 rocket minus EchoStar 23 comsat stands erect atop Launch Complex 39A at the Kennedy Space Center as seen from the press site prior to static fire test on 9 Mar. 2017. Only the top of the rocket is visible behind the historic shuttle RSS structure. This is only the second rocket to stand on pad 39A since the retirement of NASA’s Space Shuttles in July 2011. Liftoff is slated for 14 Mar 2017. Credit: Ken Kremer/Kenkremer.com
The static fire test is routinely carried out by SpaceX and confirms that both the first stage engines and the rocket are suited for liftoff.
The rocket – minus the EchoStar 23 payload – had been rolled out of the SpaceX processing hangar at the perimeter fence several days ago and then up the incline to the top of pad 39A using a newly built dedicated transporter-erector.
With the successful completion of the static fire test, the booster will be rolled back to the big processing hangar and EchoStar 23 encapsulated inside the payload fairing will be integrated on top.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
Learn more about SpaceX EchoStar 23 and CRS-10 launch to ISS, ULA SBIRS GEO 3 launch, EchoStar launch GOES-R launch, Heroes and Legends at KSCVC, OSIRIS-REx, InSight Mars lander, ULA, SpaceX and Orbital ATK missions, Juno at Jupiter, SpaceX AMOS-6, ISS, ULA Atlas and Delta rockets, Orbital ATK Cygnus, Boeing, Space Taxis, Mars rovers, Orion, SLS, Antares, NASA missions and more at Ken’s upcoming outreach events at Kennedy Space Center Quality Inn, Titusville, FL:
Mar 10, 11, 13-15: “SpaceX EchoStar 23, CRS-10 launch to ISS, ULA Atlas SBIRS GEO 3 launch, EchoStar 19 comsat launch, GOES-R weather satellite launch, OSIRIS-Rex, SpaceX and Orbital ATK missions to the ISS, Juno at Jupiter, ULA Delta 4 Heavy spy satellite, SLS, Orion, Commercial crew, Curiosity explores Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings
SpaceX Falcon 9 rocket minus EchoStar 23 comsat sits horizontal atop Launch Complex 39A at the Kennedy Space Center as seen from Playalinda Beach, Fl, prior to static fire test on 9 Mar. 2017, as technicians process the rocket. This is only the second rocket to stand on pad 39A since the retirement of NASA’s Space Shuttles in July 2011. Liftoff is slated for 14 Mar 2017. Credit: Ken Kremer/Kenkremer.comSpaceX Falcon 9 EchoStar 23 mission patch. Credit: SpaceX
An artist's illustration of a light-sail powered by a radio beam (red) generated on the surface of a planet. Could the part of the beam that misses the sail be our mysterious Fast Radio Bursts? Image Credit: M. Weiss/CfA
The extremely energetic events that we see out there in the Universe are usually caused by cataclysmic astrophysical events and activities of one sort or another. But what about Fast Radio Bursts? A pair of astrophysicists at Harvard say that the seldom seen phenomena could, maybe, possibly, be evidence of an advanced alien technology.
Fast radio bursts (FRBs) are short-lived radio pulses that last only a few milliseconds. It’s been assumed that they have some astrophysical cause. Fewer than 2 dozen of them have been detected since their discovery in 2007. They’re detected by our huge radio telescopes like the Arecibo Observatory in Puerto Rico, and the Parkes Observatory in Australia. They’re extremely energetic, and their source is a great distance from us.
The NSF’s Arecibo Observatory, which is located in Puerto Rico, is the world largest radio telescope. Arecibo detected 11 FRBs over the course of 2 months. Credit: NAIC
The two astrophysicists, Avi Loeb at the Harvard-Smithsonian Center for Astrophysics, and Manasvi Lingam at Harvard University, decided to investigate the possibility that FRBs have an alien technological origin.
“Fast radio bursts are exceedingly bright given their short duration and origin at great distances, and we haven’t identified a possible natural source with any confidence. An artificial origin is worth contemplating and checking.” – Avi Loeb, Harvard-Smithsonian Center for Astrophysics
I’ll Take ‘Alien Signals’ For $200 Alex
Loeb and Lingam began by calculating how much energy would be needed to send a signal that strong across such an enormous distance. They found that doing so with solar energy requires a solar array with an area twice the surface area of Earth. That would be enough energy, if the alien civilization was as close as we are to a star similar to our Sun.
Obviously, such a massive construction project is well beyond us. But however unlikely it sounds, it can’t be ruled out.
The pair also asked themselves questions about the viability of such a project. Would the heat and energy involved in such a solar array melt the structure itself? Their answer is that water-cooling would be sufficient to keep an array like this operating.
Their next question was, “Why build something like this in the first place?”
I’ll Take ‘Alien Spacecraft Propulsion Systems’ For $400 Alex”
The thinking behind their idea is based on an idea that we ourselves have had: Could we power a spacecraft by pushing on it with lasers? Or Microwaves? If we’ve thought of it, why wouldn’t other existing civilizations? If another civilization were doing it, what would the technology look like?
Their investigation shows that the engineering they’re talking about could power a spacecraft with a payload of a million tons. That would be about 20 times bigger than our largest cruise ship. According to Lingam, “That’s big enough to carry living passengers across interstellar or even intergalactic distances.”
If FRBs are indeed the result of an alien propulsion system, here’s how it would work: Earth is rotating and orbiting, which means the alien star and galaxy are moving relative to us. That’s why we would only see a brief flash. The beam sweeps across the sky and only hits us for a moment. The repeated appearance of the FRB could be a clue to its alien, technological origin.
The authors of the study outlining this thinking know that it’s speculative. But it’s their job to speculate within scientific constraints, which they have done. As they say in the conclusion of their paper, “Although the possibility that FRBs are produced by extragalactic civilizations is more speculative than an astrophysical origin, quantifying the requirements necessary for an artificial origin serves, at the very least, the important purpose of enabling astronomers to rule it out with future data.”
There are other interpretations when it comes to FRBs, of course. The others of another paper say that for at least one group of FRBs, known as FRB 121102, the source is likely astrophysical. According to them, FRBs likely come from “a young, highly magnetized, extragalactic neutron star.”
Lurking behind these papers are some intriguing questions that are also fun to ponder.
If the system required a solar array twice the size of Earth, where would the materials come from? If the system required water-cooling to avoid melting, where would all the water come from? It’s impossible to know, or to even begin speculating. But a civilization able to do something like this would have to be master engineers and resource exploiters. That goes without saying.
Why they might do it is another question. Probably the same reasons we would: curiosity and exploration, or maybe to escape a dying world.
Artist's concept of a terraformed Mars (left) and an O'Neill Cylinder. Credit: Ittiz/Wikimedia Commons (left)/Rick Guidice/NASA Ames Research Center (right)
The idea of terraforming Mars – aka “Earth’s Twin” – is a fascinating idea. Between melting the polar ice caps, slowly creating an atmosphere, and then engineering the environment to have foliage, rivers, and standing bodies of water, there’s enough there to inspire just about anyone! But just how long would such an endeavor take, what would it cost us, and is it really an effective use of our time and energy?
Such were the questions dealt with by two papers presented at NASA’s “Planetary Science Vision 2050 Workshop” last week (Mon. Feb. 27th – Wed. Mar. 1st). The first, titled “The Terraforming Timeline“, presents an abstract plan for turning the Red Planet into something green and habitable. The second, titled “Mars Terraforming – the Wrong Way“, rejects the idea of terraforming altogether and presents an alternative.
The former paper was produced by Aaron Berliner from the University of California, Berkeley, and Chris McKay from the Space Sciences Division at NASA Ames Research Center. In their paper, the two researchers present a timeline for the terraforming of Mars that includes a Warming Phase and an Oxygenation Phase, as well as all the necessary steps that would precede and follow.
Artist’s impression of the terraforming of Mars, from its current state to a livable world. Credit: Daein Ballard
As they state in their paper’s Introduction:
“Terraforming Mars can be divided into two phases. The first phase is warming the planet from the present average surface temperature of -60° C to a value close to Earth’s average temperature to +15° C, and recreating a thick CO² atmosphere. This warming phase is relatively easy and quick, and could take ~100 years. The second phase is producing levels of O² in the atmosphere that would allow humans and other large mammals to breath normally. This oxygenation phase is relatively difficult and would take 100,000 years or more, unless one postulates a technological breakthrough.”
Before these can begin, Berliner and McKay acknowledge that certain “pre-terraforming” steps need to be taken. These include investigating Mars’ environment to determine the levels of water on the surface, the level of carbon dioxide in the atmosphere and in ice form in the polar regions, and the amount of nitrates in Martian soil. As they explain, all of these are key to the practicality of making a biosphere on Mars.
So far, the available evidence points towards all three elements existing in abundance on Mars. While most of Mars water is currently in the form of ice in the polar regions and polar caps, there is enough there to support a water cycle – complete with clouds, rain, rivers and lakes. Meanwhile, some estimates claim that there is enough CO² in ice form in the polar regions to create an atmosphere equal to the sea level pressure on Earth.
Nitrogen is also a fundamental requirement for life and necessary constituent of a breathable atmosphere, and recent data by the Curiosity Rover indicate that nitrates account for ~0.03% by mass of the soil on Mars, which is encouraging for terraforming. On top of that, scientists will need to tackle certain ethical questions related to how terraforming could impact Mars.
Artist’s concept of a possible Mars terraforming plant. Credit: National Geographic Channel
For instance, if there is currently any life on Mars (or life that could be revived), this would present an undeniable ethical dilemma for human colonists – especially if this life is related to life on Earth. As they explain:
“If Martian life is related to Earth life – possibly due to meteorite exchange – then the situation is familiar, and issues of what other types of Earth life to introduce and when must be addressed. However, if Martian life in unrelated to Earth life and clearly represents a second genesis of life, then significant technical and ethical issues are raised.”
To break Phase One – “The Warming Phase” – down succinctly, the authors address an issue familiar to us today. Essentially, we are altering our own climate here on Earth by introducing CO² and “super greenhouse gases” to the atmosphere, which is increasing Earth’s average temperature at a rate of many degrees centigrade per century. And whereas this has been unintentional on Earth, on Mars it could be re-purposed to deliberately warm the environment.
“The timescale for warming Mars after a focused effort of super greenhouse gas production is short, only 100 years or so,” they claim. “If all the solar incident on Mars were to be captured with 100% efficiency, then Mars would warm to Earth-like temperatures in about 10 years. However, the efficiency of the greenhouse effect is plausibly about 10%, thus the time it would take to warm Mars would be ~100 years.”
Mars’ south polar ice cap, as seen in April of 2000 by the Mars Odyssey mission. Credit: NASA/JPL/MSSS
Once this thick atmosphere has been created, the next step involves converting it into something breathable for humans – where O² levels would be the equivalent of about 13% of sea level air pressure here on Earth and CO² levels would be less than 1%. This phase, known as the “Oxygenation Phase”, would take considerably longer. Once again, they turn towards a terrestrial example to show how such a process could work.
Here on Earth, they claim, the high levels of oxygen gas (O²) and low levels of CO² are due to photosynthesis. These reactions rely on the sun’s energy to convert water and carbon dioxide into biomass – which is represented by the equation H²O + CO² = CH²O + O². As they illustrate, this process would take between 100,000 and 170,000 years:
“If all the sunlight incident on Mars was harnessed with 100% efficiency to perform this chemical transformation it would take only 17 years to produce high levels of O². However, the likely efficiency of any process that can transform H²O and CO² into biomass and O² is much less than 100%. The only example we have of a process that can globally alter the CO² and O² of an entire plant is global biology. On Earth the efficiency of the global biosphere in using sunlight to produced biomass and O2 is 0.01%. Thus the timescale for producing an O² rich atmosphere on Mars is 10,000 x 17 years, or ~ 170,000 years.”
However, they make allowances for synthetic biology and other biotechnologies, which they claim could increase the efficiency and reduce the timescale to a solid 100,000 years. In addition, if human beings could utilize natural photosynthesis (which has a comparatively high efficiency of 5%) over the entire planet – i.e. planting foliage all over Mars – then the timescale could be reduced to even a few centuries.
Finally, they outline the steps that need to be taken to get the ball rolling. These steps include adapting current and future robotic missions to assess Martian resources, mathematical and computer models that could examine the processes involved, an initiative to create synthetic organisms for Mars, a means to test terraforming techniques in a limited environment, and a planetary agreement that would establish restrictions and protections.
Quoting Kim Stanley Robinson, author of the Red Mars Trilogy, (the seminal work of science fiction about terraforming Mars) they issue a call to action. Addressing how long the process of terraforming Mars will take, they assert that we “might as well start now”.
To this, Valeriy Yakovlev – an astrophysicist and hydrogeologist from Laboratory of Water Quality in Kharkov, Ukraine – offers a dissenting view. In his paper, “Mars Terraforming – the Wrong Way“, he makes the case for the creation of space biospheres in Low Earth Orbit that would rely on artificial gravity (like an O’Neill Cylinder) to allow humans to grow accustomed to life in space.
Looking to one of the biggest challenges of space colonization, Yakovlev points to how life on bodies like the Moon or Mars could be dangerous for human settlers. In addition to being vulnerable to solar and cosmic radiation, colonists would have to deal with substantially lower gravity. In the case of the Moon, this would be roughly 0.165 times that which humans experience here on Earth (aka. 1 g), whereas on Mars it would be roughly 0.376 times.
Interior view of an O’Neill Cylinder. There are alternating strips of livable surface and “windows” to let light in. Credit: Rick Guidice/NASA Ames Research Center
The long-term effects of this are not known, but it is clear it would include muscle degeneration and bone loss. Looking farther, it is entirely unclear what the effects would be for those children who were born in either environment. Addressing the ways in which these could be mitigated (which include medicine and centrifuges), Yakovlev points out how they would most likely be ineffective:
“The hope for the medicine development will not cancel the physical degradation of the muscles, bones and the whole organism. The rehabilitation in centrifuges is less expedient solution compared with the ship-biosphere where it is possible to provide a substantially constant imitation of the normal gravity and the protection complex from any harmful influences of the space environment. If the path of space exploration is to create a colony on Mars and furthermore the subsequent attempts to terraform the planet, it will lead to the unjustified loss of time and money and increase the known risks of human civilization.”
In addition, he points to the challenges of creating the ideal environment for individuals living in space. Beyond simply creating better vehicles and developing the means to procure the necessary resources, there is also the need to create the ideal space environment for families. Essentially, this requires the development of housing that is optimal in terms of size, stability, and comfort.
In light of this, Yakolev presents what he considers to be the most likely prospects for humanity’s exit to space between now and 2030. This will include the creation of the first space biospheres with artificial gravity, which will lead to key developments in terms of materials technology, life support-systems, and the robotic systems and infrastructure needed to install and service habitats in Low Earth Orbit (LEO).
Artist’s depiction of a pair of O’Neill cylinders. Credit: Rick Guidice/NASA Ames Research Center
These habitats could be serviced thanks to the creation of robotic spacecraft that could harvest resources from nearby bodies – such as the Moon and Near-Earth Objects (NEOs). This concept would not only remove the need for planetary protections – i.e. worries about contaminating Mars’ biosphere (assuming the presence of bacterial life), it would also allow human beings to become accustomed to space more gradually.
As Yakovlev told Universe Today via email, the advantages to space habitats can be broken down into four points:
“1. This is a universal way of mastering the infinite spaces of the Cosmos, both in the Solar System and outside it. We do not need surfaces for installing houses, but resources that robots will deliver from planets and satellites. 2. The possibility of creating a habitat as close as possible to the earth’s cradle allows one to escape from the inevitable physical degradation under a different gravity. It is easier to create a protective magnetic field.
“3. The transfer between worlds and sources of resources will not be a dangerous expedition, but a normal life. Is it good for sailors without their families? 4. The probability of death or degradation of mankind as a result of the global catastrophe is significantly reduced, as the colonization of the planets includes reconnaissance, delivery of goods, shuttle transport of people – and this is much longer than the construction of the biosphere in the Moon’s orbit. Dr. Stephen William Hawking is right, a person does not have much time.”
And with space habitats in place, some very crucial research could begin, including medical and biologic research which would involve the first children born in space. It would also facilitate the development of reliable space shuttles and resource extraction technologies, which will come in handy for the settlement of other bodies – like the Moon, Mars, and even exoplanets.
Ultimately, Yakolev thinks that space biospheres could also be accomplished within a reasonable timeframe – i.e. between 2030 and 2050 – which is simply not possible with terraforming. Citing the growing presence and power of the commercial space sector, Yakolev also believed a lot of the infrastructure that is necessary is already in place (or under development).
“After we overcome the inertia of thinking +20 years, the experimental biosphere (like the settlement in Antarctica with watches), in 50 years the first generation of children born in the Cosmos will grow and the Earth will decrease, because it will enter the legends as a whole… As a result, terraforming will be canceled. And the subsequent conference will open the way for real exploration of the Cosmos. I’m proud to be on the same planet as Elon Reeve Musk. His missiles will be useful to lift designs for the first biosphere from the lunar factories. This is a close and direct way to conquer the Cosmos.”
With NASA scientists and entrepreneurs like Elon Musk and Bas Landorp looking to colonize Mars in the near future, and other commercial aerospace companies developing LEO, the size and shape of humanity’s future in space is difficult to predict. Perhaps we will jointly decide on a path that takes us to the Moon, Mars, and beyond. Perhaps we will see our best efforts directed into near-Earth space.
Or perhaps we will see ourselves going off in multiple directions at once. Whereas some groups will advocate creating space habitats in LEO (and later, elsewhere in the Solar System) that rely on artificial gravity and robotic spaceships mining asteroids for materials, others will focus on establishing outposts on planetary bodies, with the goal of turning them into “new Earths”.
Between them, we can expect that humans will begin developing a degree of “space expertise” in this century, which will certainly come in handy when we start pushing the boundaries of exploration and colonization even further!
Is Earth in the range of normal when it comes to habitable planets? Or is it an outlier, with both large land masses, and large oceans? Image: Reto Stöckli, Nazmi El Saleous, and Marit Jentoft-Nilsen, NASA GSFC
For a long time, the idea of finding life on other worlds was just a science fiction dream. But in our modern times, the search for life is rapidly becoming a practical endeavour. Now, some minds at NASA are looking ahead to the search for life on other worlds, and figuring out how to search more effectively and efficiently. Their approach is centered around two things: nano-satellites and microfluidics.
Life is obvious on Earth. But it’s a different story for the other worlds in our Solar System. Mars is our main target right now, with the work that MSL Curiosity is doing. But Curiosity is investigating Mars to find out if conditions on that planet were ever favorable for life. A more exciting possibility is finding extant life on another world: that is, life that exists right now.
MSL Curiosity is busy investigating the surface of Mars, to see if that planet could have harbored life. Image: NASA/JPL/Cal-Tech
At the Planetary Science Vision 2050 Workshop, experts in Planetary Science and related disciplines gathered to present ideas about the next 50 years of exploration in the Solar System. A team led by Richard Quinn at the NASA Ames Research Center (ARC) presented their ideas on the search for extant life in the next few decades.
Their work is based on the decadal survey “Vision and Voyages for Planetary Science in the Decade 2013-2022.” That source confirms what most of us are already aware of: that our search for life should be focussed on Mars and the so-called “Ocean Worlds” of our Solar System like Enceladus and Europa. The question is, what will that search look like?
The North Polar Region of Saturn’s moon, Enceladus. Could there be an ocean world full of life under its frozen surface? Credit: NASA/JPL/Space Science Institute
Quinn and his team outlined two technologies that we could center our search around.
Nanosatellites
A nanosatellite is classified as something with a mass between 1-10 kg. They offer several advantages over larger designs.
Firstly, their small mass keeps the cost of launching them very low. In many cases, nanosatellites can be piggy-backed onto the launch of a larger payload, just to use up any excess capacity. Nanosatellites can be made cheaply, and multiples of them can be designed and built the same. This would allow a fleet of nanosatellites to be sent to the same destination.
Most of the discussion around the search for life centers around large craft or landers that land in one location, and have limited mobility. The Mars rovers are doing great work, but they can only investigate very specific locations. In a way, this creates kind of a sampling error. It’s difficult to generalize about the conditions for life on other worlds when we’ve only sampled a small handful of locations.
In 2010, NASA successfully deployed the nanosatellite NANO-Sail D from a larger, microsatellite. Image: NASA
On Earth, life is everywhere. But Earth is also the home to extremophiles, organisms that exist only in extreme, hard-to-reach locations. Think of thermal vents on the ocean floor, or deep dark caves. If that is the kind of life that exists on the target worlds in our Solar System, then there’s a strong possibility that we’ll need to sample many locations before we find them. That is something that is beyond the capabilities of our rovers. Nanosatellites could be part of the solution. A fleet of them investigating a world like Enceladus or Europa could speed up our search for extant life.
NASA has designed and built nanosatellites to perform a variety of tasks, like performing biology experiments, and testing advanced propulsion and communications technologies. In 2010 they successfully deployed a nanosatellite from a larger, microsatellite. If you expand on that idea, you can see how a small fleet of nanosatellites could be deployed at another world, after arriving there on another larger craft.
Microfluidics
Microfluidics deals with systems that manipulate very small amounts of fluid, usually on the sub-millimeter scale. The idea is to build microchips which handle very small sample sizes, and test them in-situ. NASA has done work with microfluidics to try to develop ways of monitoring astronauts’ health on long space voyages, where there is no access to a lab. Microfluidic chips can be manufactured which have only one or two functions, and produce only one or two results.
In terms of the search for extant life in our Solar System, microfluidics is a natural fit with nanosatellites. Replace the medical diagnostic capabilities of a microfluidic chip with a biomarker diagnostic, and you have a tiny device that can be mounted on a tiny satellite. Since functioning microfluidic chips can be as small as microprocessors, multiples of them could be mounted.
” Technical constraints will inevitably limit robotic missions that search for evidence of life to a few selected experiments.” – Richard.C.Quinn, et. al.
When combined with nanosatellites, microfluidics offers the possibility of the same few tests for life being repeated over and over in multiple locations. This is obviously very attractive when it comes to the search for life. The team behind the idea stresses that their approach would involve the search for simple building blocks, the complex biomolecules involved in basic biochemistry, and also the structures that cellular life requires in order to exist. Performing these tests in multiple locations would be a boon in the search.
Some of the technologies for the microfluidic search for life have already been developed. The team points out that several of them have already had successful demonstrations in micro-gravity missions like the GeneSat, the PharmaSat, and the SporeSat.
“The combination of microfluidic systems with chemical and biochemical sensors and sensor arrays offer some of the most promising approaches for extant life detection using small-payload platforms.” – Richard.C.Quinn, et. al.
Putting It All Together
We’re a ways away from a mission to Europa or Enceladus. But this paper was about the future vision of the search for extant life. It’s never too soon to start thinking about that.
There are some obvious obstacles to using nanosatellites to search for life on Enceladus or Europa. Those worlds are frozen, and it’s the oceans under those thick ice caps that we need to investigate. Somehow, our tiny nanosatellites would need to get through that ice.
Also, the nanosatellites we have now are just that: satellites. They are designed to be in orbit around a body. How could they be transformed into tiny, ocean-going submersible explorers?
There’s no doubt that somebody, somewhere at NASA, is already thinking about that.
The over-arching vision of a fleet of small craft, each with the ability to repeat basic experiments searching for life in multiple locations, is a sound one. As for how it actually turns out, we’ll have to wait and see.
A full-scale model of the JWST went on a bit of a World Tour. Here it is in Munich, Germany. Image Credit: EADS Astrium
We humans have an insatiable hunger to understand the Universe. As Carl Sagan said, “Understanding is Ecstasy.” But to understand the Universe, we need better and better ways to observe it. And that means one thing: big, huge, enormous telescopes.
In this series we’ll look at 6 of the world’s Super Telescopes:
The James Webb Space Telescope“>James Webb Space Telescope (JWST, or the Webb) may be the most eagerly anticipated of the Super Telescopes. Maybe because it has endured a tortured path on its way to being built. Or maybe because it’s different than the other Super Telescopes, what with it being 1.5 million km (1 million miles) away from Earth once it’s operating.
The JWST will do its observing while in what’s called a halo orbit at L2, a sort of gravitationally neutral point 1.5 million km from Earth. Image: NASA/JWST
If you’ve been following the drama behind the Webb, you’ll know that cost overruns almost caused it to be cancelled. That would’ve been a real shame.
The JWST has been brewing since 1996, but has suffered some bumps along the road. That road and its bumps have been discussed elsewhere, so what follows is a brief rundown.
Initial estimates for the JWST were a $1.6 billion price tag and a launch date of 2011. But the costs ballooned, and there were other problems. This caused the House of Representatives in the US to move to cancel the project in 2011. However, later that same year, US Congress reversed the cancellation. Eventually, the final cost of the Webb came to $8.8 billion, with a launch date set for October, 2018. That means the JWST’s first light will be much sooner than the other Super Telescopes.
The business end of the James Webb Space Telescope is its 18-segment primary mirror. The gleaming, gold-coated beryllium mirror has a collecting area of 25 square meters. Image: NASA/Chris Gunn
The Webb was envisioned as a successor to the Hubble Space Telescope, which has been in operation since 1990. But the Hubble is in Low Earth Orbit, and has a primary mirror of 2.4 meters. The JWST will be located in orbit at the LaGrange 2 point, and its primary mirror will be 6.5 meters. The Hubble observes in the near ultraviolet, visible, and near infrared spectra, while the Webb will observe in long-wavelength (orange-red) visible light, through near-infrared to the mid-infrared. This has some important implications for the science yielded by the Webb.
The Webb’s Instruments
The James Webb is built around four instruments:
The Near-Infrared Camera (NIRCam)
The Near-Infrared Spectrograph (NIRSpec)
The Mid-Infrared Instrument(MIRI)
The Fine Guidance Sensor/ Near InfraRed Imager and Slitless Spectrograph (FGS/NIRISS)
This image shows the wavelengths of the infrared spectrum that Webb’s instruments can observe. Image: NASA/JWST
The NIRCam is Webb’s primary imager. It will observe the formation of the earliest stars and galaxies, the population of stars in nearby galaxies, Kuiper Belt Objects, and young stars in the Milky Way. NIRCam is equipped with coronagraphs, which block out the light from bright objects in order to observe dimmer objects nearby.
NIRSpec will operate in a range from 0 to 5 microns. Its spectrograph will split the light into a spectrum. The resulting spectrum tells us about an objects, temperature, mass, and chemical composition. NIRSpec will observe 100 objects at once.
MIRI is a camera and a spectrograph. It will see the redshifted light of distant galaxies, newly forming stars, objects in the Kuiper Belt, and faint comets. MIRI’s camera will provide wide-field, broadband imaging that will rank up there with the astonishing images that Hubble has given us a steady diet of. The spectrograph will provide physical details of the distant objects it will observe.
The Fine Guidance Sensor part of FGS/NIRISS will give the Webb the precision required to yield high-quality images. NIRISS is a specialized instrument operating in three modes. It will investigate first light detection, exoplanet detection and characterization, and exoplanet transit spectroscopy.
The Science
The over-arching goal of the JWST, along with many other telescopes, is to understand the Universe and our origins. The Webb will investigate four broad themes:
First Light and Re-ionization: In the early stages of the Universe, there was no light. The Universe was opaque. Eventually, as it cooled, photons were able to travel more freely. Then, probably hundreds of millions of years after the Big Bang, the first light sources formed: stars. But we don’t know when, or what types of stars.
How Galaxies Assemble: We’re accustomed to seeing stunning images of the grand spiral galaxies that exist in the Universe today. But galaxies weren’t always like that. Early galaxies were often small and clumpy. How did they form into the shapes we see today?
The Birth of Stars and Protoplanetary Systems: The Webb’s keen eye will peer straight through clouds of dust that ‘scopes like the Hubble can’t see through. Those clouds of dust are where stars are forming, and their protoplanetary systems. What we see there will tell us a lot about the formation of our own Solar System, as well as shedding light on many other questions.
Planets and the Origins of Life: We now know that exoplanets are common. We’ve found thousands of them orbiting all types of stars. But we still know very little about them, like how common atmospheres are, and if the building blocks of life are common.
These are all obviously fascinating topics. But in our current times, one of them stands out among the others: Planets and the Origins of Life.
The recent discovery the TRAPPIST 1 system has people excited about possibly discovering life in another solar system. TRAPPIST 1 has 7 terrestrial planets, and 3 of them are in the habitable zone. It was huge news in February 2017. The buzz is still palpable, and people are eagerly awaiting more news about the system. That’s where the JWST comes in.
One big question around the TRAPPIST system is “Do the planets have atmospheres?” The Webb can help us answer this.
The NIRSpec instrument on JWST will be able to detect any atmospheres around the planets. Maybe more importantly, it will be able to investigate the atmospheres, and tell us about their composition. We will know if the atmospheres, if they exist, contain greenhouse gases. The Webb may also detect chemicals like ozone and methane, which are biosignatures and can tell us if life might be present on those planets.
You could say that if the James Webb were able to detect atmospheres on the TRAPPIST 1 planets, and confirm the existence of biosignature chemicals there, it will have done its job already. Even if it stopped working after that. That’s probably far-fetched. But still, the possibility is there.
Launch and Deployment
The science that the JWST will provide is extremely intriguing. But we’re not there yet. There’s still the matter of JWST’s launch, and it’s tricky deployment.
The JWST’s primary mirror is much larger than the Hubble’s. It’s 6.5 meters in diameter, versus 2.4 meters for the Hubble. The Hubble was no problem launching, despite being as large as a school bus. It was placed inside a space shuttle, and deployed by the Canadarm in low earth orbit. That won’t work for the James Webb.
This image shows the Hubble Space Telescope being held above the shuttle’s cargo bay by the Canadian-built Remote Manipulator System (RMS) arm, or Canadarm. A complex operation, but not as complex as JWST’s deployment. Image: NASA
The Webb has to be launched aboard a rocket to be sent on its way to L2, it’s eventual home. And in order to be launched aboard its rocket, it has to fit into a cargo space in the rocket’s nose. That means it has to be folded up.
The mirror, which is made up of 18 segments, is folded into three inside the rocket, and unfolded on its way to L2. The antennae and the solar cells also need to unfold.
Unlike the Hubble, the Webb needs to be kept extremely cool to do its work. It has a cryo-cooler to help with that, but it also has an enormous sunshade. This sunshade is five layers, and very large.
We need all of these components to deploy for the Webb to do its thing. And nothing like this has been tried before.
The Webb’s launch is only 7 months away. That’s really close, considering the project almost got cancelled. There’s a cornucopia of science to be done once it’s working.
But we’re not there yet, and we’ll have to go through the nerve-wracking launch and deployment before we can really get excited.
