It’s that time again! This week’s Carnival of Space is hosted by Pamela Hoffman at the Everyday Spacer blog.
Click here to read Carnival of Space #504.
Continue reading “Carnival of Space #504”
Carnival of Space #504
SpaceX Just Re-Used a Rocket. Why This Changes Everything
On March 30, 2017, SpaceX performed a pretty routine rocket launch. The payload was a communications satellite called SES-10, owned by a company in Luxembourg. And if all goes well, the satellite will eventually make its way to a high orbit of 35,000 km (22,000 miles) and deliver broadcasting and television services to Latin America.
For all intents and purposes, this is an absolutely normal, routine, and maybe even boring event in the space industry. Another chemical rocket blasted off another communications satellite to join the thousands of satellites that have come before.
Of course, as you probably know, this wasn’t a routine launch. It was the first step in one of the most important achievements in space flight – launch reusability. This was the second time the 14-story Falcon 9 rocket had lifted off and pushed a payload into orbit. Not Falcon 9s in general, but this specific rocket was reused.
In a previous life, this booster blasted off on April 8, 2016 carrying CRS-8, SpaceX’s 8th resupply mission to the International Space Station. The rocket launched from Florida’s Cape Canaveral, released its payload, re-entered the atmosphere and returned to a floating robotic barge in the Atlantic Ocean called Of Course I Still Love You. That’s a reference to an amazing series of books by Iain M. Banks.
Why is this such an amazing accomplishment? What does the future hold for reusability? And who else is working on this?
Developing a rocket that could be reused has been one of the holy grails of the space industry, and yet, many considered it an engineering accomplishment that could never be achieved. Trust me, people have tried in the past.
Portions of the space shuttle were reused – the orbiter and the solid rocket boosters. And a few decades ago, NASA tried to develop the X-33 as a single stage reusable rocket, but ultimately canceled the program.
To reuse a rocket makes total sense. It’s not like you throw out your car when you return from a road trip. You don’t destroy your transatlantic airliner when you arrive in Europe. You check it out, do a little maintenance, refuel it, fill it with passengers and then fly it again.
According to SpaceX founder Elon Musk, a brand new Falcon 9 first stage costs about $30 million. If you could perform maintenance, and then refill it with fuel, you’d bring down subsequent launches to a few hundred thousand dollars.
SpaceX is still working out what a “flight-tested” launch will cost on a reused Falcon 9 will cost, but it should turn into a significant discount on SpaceX’s already aggressive prices. If other launch providers think they’re getting undercut today, just wait until SpaceX really gets cranking with these reused rockets.
For most kinds of equipment, you want them to have been re-used many times. Cars need to be taken to the test track, airplanes are flown on many flights before passengers ever climb inside. SpaceX will have an opportunity to test out each rocket many times, figuring out where they fail, and then re-engineering those components. This makes for more durable and safer launch hardware, which I suspect is the actual goal here – safety, not cost.
In addition to the first stage, SpaceX also re-used the satellite fairing. This is the covering that makes the payload more aerodynamic while the rocket moves through the lower atmosphere. The fairing is usually ejected and burns up on re-entry, but SpaceX has figured out how to recover that too, saving a few more million.
SpaceX’s goals are even more ambitious. In addition to the first stage booster and launch fairing, SpaceX is looking to reuse the second stage booster. This is a much more complicated challenge, because the second stage is going much faster and needs to lose a lot more velocity. In late 2014, they put their plans on hold for a second stage reuse.
SpaceX’s next big milestone will be to decrease the reuse time. From almost a year to under 24 hours.
Sometime this year, SpaceX is expected to do the first launch of the Falcon Heavy. A launch system that looks like it’s made up of 3 Falcon-9 rockets bolted together. Since that’s basically what it is.
The center booster is a reinforced Falcon-9, with two additional Falcon-9s as strap-on boosters. Once the Falcon Heavy lifts off, the three boosters will detach and will individually land back on Earth, ready for reassembly and reuse. This system will be capable of carrying 54,000 kilograms into low Earth orbit. In addition, SpaceX is hoping to take the technology one more step and have the upper stage return to Earth.
Imagine it. Three boosters and upper stage and payload fairing all returning to Earth and getting reused.
And waiting in the wings, of course, is SpaceX’s huge Interplanetary Transport System, announced by Elon Musk in September of 2016. The super-heavy lift vehicle will be capable of carrying 300,000 kilograms into low Earth orbit.
For comparison, the Apollo era Saturn V could carry 140,000 kg into low Earth orbit, so this thing will be much much bigger. But unlike the Saturn V, it’ll be capable of returning to Earth, and landing on its launch pad, ready for reuse.
SpaceX just crossed a milestone, but they’re not the only player in this field.
Perhaps the biggest competitor to SpaceX comes from another internet entrepreneur: Amazon’s Jeff Bezos, the 2nd richest man in the world after Bill Gates. Bezos founded his own rocket company, Blue Origin in Seattle, which had been working in relative obscurity for the last decade. But in the last few years, they demonstrated their technology for reusable rocket flight, and laid out their plans for competing with SpaceX.
In April 2015, Blue Origin launched their New Shepard rocket on a suborbital trajectory. It went up to an altitude of about 100 km, and then came back down and landed on its launch pad again. It made a second flight in November 2015, a third flight in April 2016, and a fourth flight in June 2016.
That does sound exciting, but keep in mind that reaching 100 km in altitude requires vastly less energy than what the Spacex Falcon 9 requires. Suborbital and orbital are two totally milestones. The New Shepard will be used to carry paying tourists to the edge of space, where they can float around weightlessly in the vomit of the other passengers.
But Blue Origin isn’t done. In September 2016, they announced their plans for the follow-on New Glenn rocket. And this will compete head to head with SpaceX. Scheduled to launch by 2020, like, within 3 years or so, the New Glenn will be an absolute monster, capable of carrying 45,000 kilograms of cargo into low Earth orbit. This will be comparable to SpaceX’s Falcon Heavy or NASA’s Space Launch System.
Like the Falcon 9, the New Glenn will return to its launch pad, ready for a planned reuse of 100 flights.
A decade ago, the established United Launch Alliance – a consortium of Boeing and Lockheed-Martin – was firmly in the camp of disposable launch systems, but even they’re coming around to the competition from SpaceX. In 2014, they began an alliance with Blue Origin to develop the Vulcan rocket.
The Vulcan will be more of a traditional rocket, but some of its engines will detach in mid-flight, re-enter the Earth’s atmosphere, deploy parachutes and be recaptured by helicopters as they’re returning to the Earth. Since the engines are the most expensive part of the rocket, this will provide some cost savings.
There’s another level of reusability that’s still in the realm of science fiction: single stage to orbit. That’s where a rocket blasts off, flies to space, returns to Earth, refuels and does it all over again. There are some companies working on this, but it’ll be the topic for another episode.
Now that SpaceX has successfully launched a first stage booster for the second time, this is going to become the new normal. The rocket companies are going to be fine tuning their designs, focusing on efficiency, reliability, and turnaround time.
These changes will bring down the costs of launching payloads to orbit. That’ll mean it’s possible to launch satellites that were too expensive in the past. New scientific platforms, communications systems, and even human flights become more reasonable and commonplace.
Of course, we still need to take everything with a grain of salt. Most of what I talked about is still under development. That said, SpaceX just reused a rocket. They took a rocket that already launched a satellite, and used it to launch another satellite.
It’s a pretty exciting time, and I can’t wait to see what happens next.
Now you know how I feel about this accomplishment, I’d like to hear your thoughts. Do you think we’re at the edge of a whole new era in space exploration, or is this more of the same? Let me know your thoughts in the comments.
Hubble Sees Intense Auroras on Uranus
Earth doesn’t have a corner on auroras. Venus, Mars, Jupiter, Saturn, Uranus and Neptune have their own distinctive versions. Jupiter’s are massive and powerful; Martian auroras patchy and weak.
Auroras are caused by streams of charged particles like electrons that originate with solar winds and in the case of Jupiter, volcanic gases spewed by the moon Io. Whether solar particles or volcanic sulfur, the material gets caught in powerful magnetic fields surrounding a planet and channeled into the upper atmosphere. There, the particles interact with atmospheric gases such as oxygen or nitrogen and spectacular bursts of light result. With Jupiter, Saturn and Uranus excited hydrogen is responsible for the show.
Credit: NASA, ESA, and L. Lamy (Observatory of Paris, CNRS, CNES)
Auroras on Earth, Jupiter and Saturn have been well-studied but not so on the ice-giant planet Uranus. In 2011, the Hubble Space Telescope took the first-ever image of the auroras on Uranus. Then in 2012 and 2014 a team from the Paris Observatory took a second look at the auroras in ultraviolet light using the Space Telescope Imaging Spectrograph (STIS) installed on Hubble.
Two powerful bursts of solar wind traveling from the sun to Uranus stoked the most intense auroras ever observed on the planet in those years. By watching the auroras over time, the team discovered that these powerful shimmering regions rotate with the planet. They also re-discovered Uranus’ long-lost magnetic poles, which were lost shortly after their discovery by Voyager 2 in 1986 due to uncertainties in measurements and the fact that the planet’s surface is practically featureless. Imagine trying to find the north and south poles of a cue ball. Yeah, something like that.
In both photos, the auroras look like glowing dots or patchy spots. Because Uranus’ magnetic field is inclined 59° to its spin axis (remember, this is the planet that rotates on its side!) , the auroral spots appear far from the planet’s north and south geographic poles. They almost look random but of course they’re not. In 2011, the spots lie close to the planet’s north magnetic pole, and in 2012 and 2014, near the south magnetic pole — just like auroras on Earth.
An auroral display can last for hours here on the home planet, but in the case of the 2011 Uranian lights, they pulsed for just minutes before fading away.
Want to know more? Read the team’s findings in detail here.
What Constellation is the Sun in?
Since ancient times, astronomers have organized the stars into various constellations. We have the Big Dipper (Ursa Major), Orion the Hunter, and his “Greater Dog” and “Lesser Dog”(Canis Major and Canis Minor). And those are just some of the better-known ones. But have you ever wondered if the Sun belongs to one of these collections of stars?
The simple answer is that – in accordance with both ancient astrological tradition and modern astronomy – the Sun technically has no constellation. But if you were to change locations and travel to a new star system, you would then be able to view the Sun as we do other distant collection of stars. Unfortunately, depending on where you are, the answer would change.
The Zodiac:
First, let us consider the astrological answer to this question. Unless you were born prior to the Scientific Revolution – during which time Nicolaus Copernicus proposed the heliocentric model of the Solar System – you know that the Earth revolves around the Sun. Over the course of a year, the position of the stars changes as the Earth’s position relative to the Sun changes.
During the year, the Sun passes through each of the constellations of the Zodiac. For example, in August, the Sun is in Leo, and then in September, the Sun is in Virgo. Your astrological sign is based on this. What this means is that the Sun is part of each constellation of the Zodiac over the course of a single year, so it can’t be said to be in any single constellation.
However, astrology is an obsolete and entirely unscientific practice. And if someone were to ask which constellation the Sun is in, surely they are seeking an answer that was astronomical (and not astrological) in nature. For that, we must consider what the constellations are in scientific terms.
The 88 Constellations:
Since ancient times, astronomers and scholars have been keeping track of “asterisms” (aka. constellations) in the night sky. By definition, these are collections of stars that, when viewed from Earth, appear in the same general area as each other night after night. In reality, they are actually located in very different locations, and can sometimes be up to thousands of light-years away from each other.
During the 2nd century CE, Hellenistic astronomer Claudius Ptolemaeus (Ptolemy) organized the constellations into a single treatise. This treatise, known as the Almagest, was the definitive source on Greek astronomy, and contained the names and meanings of the then-known 48 constellations. For over a thousand years, this work would remain canon for European and Islamic Astronomers.
Thanks to the Scientific Revolution and “Age of Exploration” – ca. 15th to 18th centuries CE – astronomers became aware of many more constellations. This was due to extensive overseas exploration, which brought European traders, explorers and waves of colonization to the Southern Hemisphere, East Asia and the Americas.
By 1922, the International Astronomical Union (IAU) officially divided the celestial sphere into 88 constellations. Of these, 36 lie predominantly in the northern sky while the other 52 lie predominantly in the southern. While it would take years to work out the exact delineation between these constellations, and many corresponded to their Greco-Roman predecessors, these 88 modern constellations would remain in use until this day.
However, these constellations divide up the night sky based on how it is viewed from Earth. Once again, our Sun cannot be considered to lie in any one of them because – relative to the Earth-bound observer – it passes through them. Alas, the only way to answer this question is to change our perspective.
From Other Star Systems:
If you could move away to another star, then our Sun would indeed appear to be part of the background stars. For example, if you were to travel to a planet orbiting the nearest star to the Solar System – Alpha Centauri (aka. Rigil Kentaurus) – then the Sun would indeed appear to be part of a constellation.
To be scientifically accurate, let us consider a planet that we actually know of. This would be the rocky extrasolar planet recently discovered around Proxima Centauri, which is known as Proxima b. Viewed from the surface of this planet, the Sun would appear to be part of the Cassiopeia constellation. However, rather than forming a W shape, our Sun would form a sixth point on its “western” end, making it look like a mountain chain (or a scribbled line).
But if you went to a different star system, the Sun’s position would change, depending on the direction. As such, the Sun really isn’t in any constellation per se. But then again, none of the other stars that make up the Milky Way are either. Much like what Einstein’s Theory of Relativity teaches us about space and time, the constellations themselves are relative to the observer.
We have written many interesting articles about the Sun and the constellations here at Universe Today. Here’s What are the Constellations?, Zodiac Signs and their Dates?, Where is the Sun?, and Earth’s Orbit Around the Sun.
For more information on how our Sun looks from Alpha Centauri, be sure to check out this page from Learn Astronomy. SAnd here’s an article about all 88 recognized constellations.
Astronomy Cast also has episodes on the subject. Here’s Episode 30: The Sun, Spots and All and Episode 157: Constellations.
Sources:
- IAU – The Constellation
- Wikipedia – Constellation
- NASA/Starchild – 88 Officially Recognized Constellations
- Learn Astronomy – How Would Our Sun Look From Our Nearest Star System?
Messier 39 – The NGC 7092 Open Star Cluster
Welcome back to Messier Monday! In our ongoing tribute to the great Tammy Plotner, we take a look at the open galactic star cluster known as Messier 39. Enjoy!
During the 18th century, famed French astronomer Charles Messier noted the presence of several “nebulous objects” in the night sky. Having originally mistaken them for comets, he began compiling a list of them so that others would not make the same mistake he did. In time, this list (known as the Messier Catalog) would come to include 100 of the most fabulous objects in the night sky.
One of these objects is known as Messier 39, an open star cluster located in the direction of the Cygnus constellation. Because of its proximity to Deneb and its size – it is actually larger in the night sky than a full Moon – it is easily observed using binoculars and small, low magnification telescopes.
Description:
Positioned only about 800 light years away from our solar system, this 300 million year old group of about 30 stars may look like they are spread fairly far apart in the sky. But as clusters go, they are close, really close! This group is gathered in space in only a 7 light year neighborhood! All of its stars are main sequence and the very brightest of them are just about to evolve into the red giant star phase.
In a study done by Jean Claude Mermilliod (et al), they conducted a long-term monitoring of solar-type dwarfs with CORAVEL – a study which took 19 years. While most individual radial velocities were never published – apart from a small number of spectroscopic binaries – the stars themselves and their properties were well documented in the works of B. Uyaniker and T. L. Landecker of the National Research Council, Herzberg Institute of Astrophysics.
As Uyaniker and Landecker claimed in their 2002 study, “A Highly Ordered Faraday-Rotation Structure in the Interstellar Medium“:
“We describe a Faraday rotation structure in the interstellar medium detected through polarimetric imaging at 1420 MHz from the Canadian Galactic Plane Survey (CGPS). The structure, at l = 918,b = -25, has an extent of ~2°, within which polarization angle varies smoothly over a range of ~100°. Polarized intensity also varies smoothly, showing a central peak within an outer shell. This region is in sharp contrast to its surroundings, where low-level chaotic polarization structure occurs on arcminute scales. The Faraday rotation structure has no counterpart in radio total intensity and is unrelated to known objects along the line of sight, which include a Lynds Bright Nebula, LBN 416, and the star cluster M39 (NGC 7092). It is interpreted as a smooth enhancement of electron density. The absence of a counterpart, in either optical emission or total intensity, establishes a lower limit to its distance. An upper limit is determined by the strong beam depolarization in this direction. At a probable distance of 350 ± 50 pc, the size of the object is 10 pc, the enhancement of electron density is 1.7 cm-3, and the mass of ionized gas is 23 M. It has a very smooth internal magnetic field of strength 3 UG, slightly enhanced above the ambient field. G91.8-2.5 is the second such object to be discovered in the CGPS, and it seems likely that such structures are common in the magneto-ionic medium.”
So where do these gases come from? Perhaps they are there all along. As Yu N. Efremov and T.G. Sitnik wrote in their 1988 study:
“It is found that about 90% of young clusters o-b2 and OB-associations situated within 3 kpc from the Sun are united into complexes with diameters from 150 to 700 pc. Almost all complexes contain giant molecular clouds with masses. A number of complexes (mostly large ones)-are connected with giant H I clouds; a few of small complexes are situated in the H I-caverns. Older (>b2) cluster avoid the regions occupied by young star groups. Complexes often have an hierarchic structure; some neighbouring complexes may be united into supercomplexes with diameters about 1.5 kpc.”
Does this mean it’s possible that M39 could be more than one cluster combined? As H. Schneider wrote in his 1987 study:
“Early-type stars up to 12.0 mag and spectral type F2 in two young northern clusters were investigated by means of Stromgren and H-beta photometry. The distance and reddening of the clusters were estimated, and the membership of the stars discussed. In the case of NGC 7039 a distance of 675 pc and a color excess of E(b-y) = 0.056 were found; the respective values for NGC 7063 were 635 pc and E(b-y) = 0.062. The reality of NGC 7039 is somewhat puzzling: it seems that there exists a loose star aggregate called NGC 7039, containing about six to nine stars, and in the background another cluster at a distance of about 1500 pc. Besides this, variable reddening across the cluster area is probable.”
History of Observation:
While it is possible this bright star cluster was remarked upon by Aristotle as a cometary appearing object about 325 BC, and it is also possible that it may have been discovered by Le Gentil in 1750, the fact remains M39 is most frequently attributed to be an original discovery of Charles Messier. As he recorded in his notes:
“In the night of October 24 to 25, 1764, I observed a cluster of stars near the tail of Cygnus: One distinguishes them with an ordinary (nonachromatic) refractor of 3 and a half feet; they don’t contain any nebulosity; its extension can occupy a degree of arc. I have compared it with the star Alpha Cygni, and I have found its position in right ascension of 320d 57′ 10″, and its declination of 47d 25′ 0″ north.”
Because Sir William Herschel did not publish his findings on Messier’s works, very few have read his observations of the object -“Consists of such large and straggling stars that I could not tell where it began nor where it ended. It cannot be called a cluster.” However, it would later go on to receive a New General Catalog (NGC) designation by Sir John Herschel who would describe it as “A star of 7th mag [position taken], one of a large loose cluster of stars of 7th to 10th magnitude; very coarsely scattered, and filling many fields.”
Even as accomplished as historic observers were, they sometimes didn’t always do the right thing. In the case of Messier 39, it is so close to us that it appears large dimensionally in the sky – and therefore needs less magnification instead of more to be properly studied as a whole. However, don’t always put away the magnfication, because as Admiral Smyth reports:
“A loose cluster, or rather splashy galaxy field of stars, in a very rich visinity between the Swan’s tail and the Lizard, due south of Beta Cephei, and east-north-east of Deneb [Alpha Cygni]. This was picked up by Messier in 1764, with his 3 1/2 foot telescope, and registered as being a degree in diameter. Among them there are several pairs, of which a couple were slightly estimated; the first being the brightest star (7m) and its comes, and the second a pretty pair of 10th-magnitudes.”
Locating Messier 39:
This coarse open star cluster is easily found in small optics. Start first by identifying the very large constellation of Cygnus and pinpointing its brightest, northernmost star. Aim you binoculars there. You’ll find M39 about 9 degrees east and a bit north of Deneb (Alpha Cygni). If at first you don’t succeed, try looking at Deneb from a dark sky location and see if you can spot a small, hazy patch about a fist width away to the east. There’s your star cluster!
It will also show easily in the telescope finderscope as a hazy patch and even begin resolution with larger aperture finders. M39 is very well suited to light polluted skies and moonlit observing and will even hold up well to less than ideal sky conditions. Small instruments will easily see a bright handful of stars while larger telescopes will resolve many more faint members and pairs. Because of its large apparent size, you’ll enjoy viewing M39 far more if you use the least amount of magnification possible.
Enjoy this star-studded cluster and the great Milky Way field that frames it!
And here are the quick facts on this Messier Object to help get you started:
Object Name: Messier 39
Alternative Designations: M39, NGC 7092
Object Type: Galactic Open Star Cluster
Constellation: Cygnus
Right Ascension: 21 : 32.2 (h:m)
Declination: +48 : 26 (deg:m)
Distance: 0.825 (kly)
Visual Brightness: 4.6 (mag)
Apparent Dimension: 32.0 (arc min)
We have written many interesting articles about Messier Objects here at Universe Today. Here’s Tammy Plotner’s Introduction to the Messier Objects, , M1 – The Crab Nebula, M8 – The Lagoon Nebula, and David Dickison’s articles on the 2013 and 2014 Messier Marathons.
Be to sure to check out our complete Messier Catalog. And for more information, check out the SEDS Messier Database.
Sources:
Astronomy Cast Ep. 445: Animals in Space Pt. 1: Insects and Arachnids
We’ve talked about animals traveling to space in the past, but it’s time to take another look, with many other creatures making the trip to the void. Today we’re going to talk about the spineless insects and arthropods, and those tough as nails waterbears – tardigrades.
Visit the Astronomy Cast Page to subscribe to the audio podcast!
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.
Hubble Takes Advantage Of Opposition To Snap Jupiter
On April, 7th, 2017, Jupiter will come into opposition with Earth. This means that Earth and Jupiter will be at points in their orbit where the Sun, Earth and Jupiter will all line up. Not only will this mean that Jupiter will be making its closest approach to Earth – reaching a distance of about 670 million km (416 million mi) – but the hemisphere that faces towards us will be fully illuminated by the Sun.
Because of its proximity and its position, Jupiter will be brighter in the night sky than at any other time during the year. Little wonder then why NASA and the ESA are taking advantage of this favorable alignment to capture images of the planet with the Hubble Space Telescope. Already, on April 3rd, Hubble took the wonderful color image (shown above) of Jupiter, which has now been released.
Using its Wide Field Camera 3 (WFC3), Hubble was able to observe Jupiter in the visible, ultraviolet and infrared spectrum. From these observations, members of the Hubble science team produced a final composite image that allowed features in its atmosphere – some as small as 130 km across – to be discernible. These included Jupiter’s colorful bands, as well as its massive anticyclonic storms.
The largest of these – the Great Red Spot – is believed to have been raging on the surface ever since it was first observed in the 1600s. In addition, it is estimated that the wind speeds can reach up to 120 m/s (430 km/h; 267 mph) at its outer edges. And given its dimensions – between 24-40,000 km from west to east and 12-14,000 km from south to north – it is large enough to swallow the Earth whole.
Astronomers have noticed how the storm appears to have been shrinking and expanding throughout its recorded history. And as the latest images taken by Hubble (and by ground-based telescopes) have confirmed, the storm continues to shrink. Back in 2012, it was even suggested that the Giant Red Spot might eventually disappear, and this latest evidence seems to confirm that.
No one is entirely sure why the storm is slowly collapsing; but thanks to images like these, researchers are gaining a better understanding of what mechanisms power Jupiter’s atmosphere. Aside from the Great Red Spot, the similar but smaller anticyclonic storm in the farther southern latitudes – aka. Oval BA or “Red Spot Junior” – was also captured in this latest image.
Located in the region known as the South Temperate Belt, this storm was first noticed in 2000 after three small white storms collided. Since then, the storm has increased in size, intensity and changed color (becoming red like its “big brother”). It is currently estimated that wind speeds have reached 618 km/h (384 mph), and that it has become as large as Earth itself (over 12,000 km, 7450 mi in diameter).
And then there are the color bands that make up Jupiter’s surface and give it its distinct appearance. These bands are essentially different types of clouds that run parallel to the equator and differ in color based on their chemical compositions. Whereas the whiter bands have higher concentrations of ammonia crystals, the darker (red, orange and yellow) have lower concentrations.
Similarly, these color patterns are also affected by the upwelling of compounds that change color when they are exposed to ultraviolet light from the Sun. Known as chromophores, these colorful compounds are likely made up of sulfur, phosphorous and hydrocarbons. The planet’s intense wind speeds of up to 650 km/h (~400 mph) also ensure that the bands are kept separate.
These and other observations of Jupiter are part of the Outer Planet Atmospheres Legacy (OPAL) progamme. Dedicated to ensuring that Hubble gets as much information as it can before it is retired – sometime in the 2030s or 2040s – this program ensures that time is dedicated each year to observing Jupiter and the other gas giants. From the images obtained, OPAL hopes to create maps that planetary scientists can study long after Hubble is decommissioned.
The project will ultimately observe all of the giant planets in the Solar System in a wide range of filters. The research that this enables will not only help scientists to study the atmospheres of the giant planets, but also to gain a better understanding of Earth’s atmosphere and those of extrasolar planets. The programme began in 2014 with the study of Uranus and has been studying Jupiter and Neptune since 2015. In 2018, it will begin viewing Saturn.
Further Reading: Hubble Space Telescope
Finally! A Low Mass Super-Earth With Some Funky Atmosphere
In 2015, astronomers discovered an intriguing extrasolar planet located in a star system some 39 light years from Earth. Despite orbiting very close to its parent star, this “Venus-like” planet – known as GJ 1138b – appeared to still be cool enough to have an atmosphere. In short order, a debate ensued as to what kind of atmosphere it might have, whether it was a “dry Venus” or a “wet Venus”.
And now, thanks to the efforts of an international team of researchers, the existence of an atmosphere has been confirmed around GJ 1138b. In addition to settling the debate about the nature of this planet, it also marks the first time that an atmosphere has been detected around a low-mass Super-Earth. On top of that, GJ 1138b is now the farthest Earth-like planet that is known to have an atmosphere.
Led by John Southworth (of Keele University) and Luigi Mancini (of the University of Rome Tor Vergata), the research team included members from the Max Planck Institute for Astronomy (MPIA), the National Institute for Astrophysics (INAF), the University of Cambridge and Stockholm University. Their study, titled “Detection of the atmosphere of the 1.6 Earth mass exoplanet GJ 1132b“, recently appeared in The Astrophysical Journal.
Using the GROND imager on the La Silla Observatory’s 2.2m ESO/MPG telescope, the team monitored GJ 1132b in different wavelengths as it transited in front of its parent star. Given the planet’s orbital period (1.6 days), these transits happen quite often, which presented plenty of opportunities to view it pass in front of its star. In so doing, they monitored the star for slight decreases in its brightness.
As Dr. Southworth explained to Universe via email, these observations confirmed the existence of an atmosphere:
“What we did was to measure the amount of dimming at 7 different wavelengths in optical and near-infrared light. At one of these wavelengths (IR) the planet seemed to be slightly bigger. This indicated that the planet has a large atmosphere around it which allows most of the starlight to pass through, but is opaque at one wavelength.”
The team members from the University of Cambridge and the MPIA then conducted simulations to see what this atmosphere’s composition could be. Ultimately, they concluded that it most likely has a thick atmosphere that is rich in water and/or methane – which contradicted recent theories that the planet had a thin and tenuous atmosphere (i.e. a “dry Venus”).
It was also the first time that an atmosphere has been confirmed around a planet that is not significantly greater in size and mass to Earth. In the past, astronomers have detected atmospheres around many other exoplanets. But in these cases, the planets were either gas giants or planets that were many times Earth’s size and mass (aka. “Super-Earths”). GJ 1132b, however, is 1.6 times as massive as Earth, and measures 1.4 Earth radii.
In addition, these findings are a significant step in the search for life beyond our Solar System. At present, astronomers seek to determine the chemical composition of a planet’s atmosphere to determine if it could be habitable. Where the right combination of chemical imbalances exist, the presence of living organisms is seen as a possible cause.
By being able to determine that a planet at lower end of the super-Earth scale has an atmosphere, we are one step closer to being able to determine exoplanet habitability. The detection of an atmosphere-bearing planet around an M-type (red dwarf) star is also good news in and of itself. Low-mass red dwarf stars are the most common star in the galaxy, and recent findings have indicated that they might be our best shot for finding habitable worlds.
Besides detecting several terrestrial planets around red dwarf stars in recent years – including seven around a single star (TRAPPIST-1) – there is also research that suggests that these stars are capable of hosting large numbers of planets. At the same time, there have been concerns about whether red dwarfs are too variable and unstable to support habitable worlds.
As Southworth explained, spotting an atmosphere around a planet that closely orbits a red dwarf could help bolster the case for red dwarf habitability:
“One of the big issues has been that very-low-mass stars typically have strong magnetic fields and thus throw out a lot of X-ray and ultraviolet light. These high-energy photons tend to destroy molecules in atmospheres, and might also evaporate them completely. The fact that we have detected an atmosphere around GJ 1132b means that this kind of planet is indeed capable of retaining an atmosphere for billions of years, even whilst being bombarded by the high-energy photons from their host stars.
In the future, GJ 1132b is expected to be a high-priority target for study with the Hubble Space Telescope, the Very Large Telescope (VLT) at the Paranal Observatory in Chile, and next-generation telescopes like the James Webb Space Telescope (scheduled for launch in 2018). Already, observations are being made, and the results are being eagerly anticipated.
I’m sure I’m not the only one who would like to hear what astronomers discover as they set their sights on this nearby star system and it’s Venus-like world! In the meantime, be sure to check out this video about GJ 1132b, courtesy of MIT news:
Further Reading: Max Planck Institute for Astronomy
Carnival of Space #503
This week’s Carnival of Space is hosted by Brian Wang at his Next Big Future blog.
Click here to read Carnival of Space #503
Continue reading “Carnival of Space #503”
Weekly Space Hangout – April 7, 2017: Weekly News Roundup
Host: Fraser Cain (@fcain)
Guests:
Paul M. Sutter (pmsutter.com / @PaulMattSutter)
Their stories this week:
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 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 linked above 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<