February – Guide to Mercury

The planet Mercury is the closest world to the Sun, and lies in a region of the solar system inhabited by rocks from comets that that never made a safe passing around our parent star. Also leftover debris from the origin of the Sun's family. In this month's program I present a Guide to Mercury.

Jupiter is the most ancient Planet in The Sun’s family

Jupiter formed in a geologic blink. Its rocky core coalesced less than a million years after the beginning of our Solar System, scientists reported Monday in the Proceedings of the National Academy of Sciences. Within another 2 or 3 million years, that core grew to 50 times the mass of Earth.

Scientists have previously built computer models of the birth of Jupiter. But this study "is the first time that we can say something about Jupiter based on measurements done in the lab," said study co-author Thomas Kruijer, a researcher at the Lawrence Livermore National Laboratory in California.

To probe the planet's creation, experts sampled extra-terrestrial material that happens to land on Earth - ancient meteorites.

Our Solar System began as a disk of dust and gas 4.6 billion years ago. Of the planets, first came the gas giants, followed by such rock-and-metal terrestrial worlds as Earth. Jupiter is the biggest of the brood.

Despite being mostly gas by bulk, it's more than 300 times the mass of Earth. For that reason astronomers suspect the planet was the oldest, able to scoop up more material out of the disk before its younger siblings appeared.

The new study supports the idea of a firstborn Jupiter. When Jupiter formed, the growing planet swept up a great swath of gas and dust as it circled the sun.

What's more, it acted as a barrier to shield the inner Solar System from wayward meteorites. When the Solar System was about 1 million years old, Jupiter's gravity was strong enough to prevent rocks from crossing beyond its orbit, like a club bouncer who forces latecomers to wait on the sidewalk.

"At about 1 million years, you have Jupiter getting big enough to cut off the inner Solar System from the outer Solar System," said Brown University's Brandon Johnson, a planetary scientist who was not involved with the new research.

Then, when the Solar System was around 4 million years old, Jupiter grew to about 50 Earth masses and headed toward the sun. This lowered the bouncer's velvet rope, allowing the outer asteroids to mix with the inner rocks.

Today, they're jumbled together in a single belt, which exists between Jupiter and Mars. Rocks from this mixture land on Earth, where scientists such as Kruijer can study them.

The new study adds evidence to the idea that Jupiter temporarily split the population of meteorites in the Solar System in two: those between Jupiter and the Sun, and those beyond Jupiter.

If a pair of inner and outer space rocks landed in your front yard, and you picked them up after they cooled down and the dust settled, you wouldn't be able to spot a difference.

But Kruijer and his colleagues can measure specific chemical signatures in meteorites - which reveal not only the rocks' age but which of the two groups they once belonged to.

It was only recently that technological advances allowed scientists to measure the differences in the two, Kruijer said.

The meteorite groups separated around 1 million years after the Solar System formed, and stayed apart until about 4 million years post-formation, according to the new analysis. Crucially, the two populations existed simultaneously for a few million years.

"It cannot be a temporal change. It must be a spatial separation," Kruijer said.

Something must have kept them apart. The most likely culprit, the authors of the study say, is a young Jupiter. "It's hard to think of any other possibility," he said.

"This is interesting work and presents an interesting result, which conforms well with our existing understanding," said Konstantin Batygin, a planetary astrophysicist at the California Institute of Technology who was not involved with the research. "It may very well be what had happened."

Planetary scientists are like detectives, Batygin said, scouring a scene for hints about what transpired.

"In a crime scene it's the little splatters of blood on the ceiling," he said, "that will tell you more than the dismembered limbs."

In this analogy the planets are the chopped limbs and the meteorites the bloody spray. But, as with hunting for murder clues, he added, "there's always room for doubt with these types of problems."

It might be that the structure of the early disk kept the meteorite groups isolated, said Kevin Walsh, an astronomer at Southwest Research Institute in Colorado who was not involved with this work.

"The key point the authors make is that Jupiter must form to keep these asteroid reservoirs separate while they form," he said in an email.

"It is possible that we have a naïve understanding of the way asteroid building blocks could move in an early Solar System, and that a Jupiter mass planet isn't necessary."

But such an early Jupiter jibes with other ideas about the early Solar System.

One concept, called the grand tack hypothesis, casts Jupiter as a wanderer. In the grand tack hypothesis, first proposed by Walsh and other scientists in 2011, Jupiter began to barrel toward the centre of the Solar System.

That was, until Saturn formed, pulling Jupiter backward. This pendulous wrecking-ball motion could be responsible for, among other things, the mixing of the meteorite groups into one belt.

And it's likely that this young and massive Jupiter is responsible for a small Earth with a thin atmosphere. "We occupy a somewhat strange world, galactically speaking," Batygin said.

Earth, which formed about 100 million years after the solar nebula, lacked the gravity for a thick "nasty hydrogen helium atmosphere" found on other worlds.

Thank Jupiter for sucking up most of that material.

Exoplanet hunters looking at other star systems have found several super-Earths, planets larger than Earth but smaller than gas giants like Neptune. Few exoplanets are as small as two Earths and exist in the habitable zone of their star.

Kruijer speculated that the young Jupiter is the reason our Solar System does not have any super-Earths close to our star.

In this light Jupiter is a pillar of the Solar System. "Even in its infancy, Jupiter really controlled the dynamics and evolution of the Solar System," Johnson said.

"It's the biggest thing there is. Even at a million years it's changing the way that our Solar System looked."

On This day 13 June 2017

THE MOONS OF THE PLANETS MARS, JUPITER AND SATURN DURING JUNE 2017
Please click on the images to enlarge

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Comet C/2015 V2 Johnson is at perihelion today at a distance of just over 152 million miles from the Sun. The ‘green’ comet is visible in a pair of 10x50 binoculars, and can be found in the constellation of Bootes, before moving south into Virgo on 15 June. RA 14h 24m 24.8s DEC +07 13’ 27”.

Today THE MOON lies in the constellation of Sagittarius RA 20h 57m33s Dec -15 56’ 55” Lunation 19.21 days, illuminated 82.6% Libration, Position Angle -17.8° Latitude -00° 42’ in Longitude -05h 56m.

Today MERCURY is visible in the morning RA 04h 50m 28.7s Dec +22° 18’ 35” Mag -2.0 Diameter 5.28” Phase 0.930

Today Venus (Mag ‒4.4) is also visible in the morning sky. RA 2h 24m 47.8s Dec +11° 35’ 04” Diameter 20.84” Phase 0.56.

Today MARS (Mag +1.7) lies in the constellation Gemini close to the open cluster M35 RA 06h 27m 05.7” Dec +24° 13’ 45” Diameter 3.8”. The planet is visible in the west after sunset.

The Asteroid CERES was in conjunction with the Sun on 6 June

Juno (Mag +10) Constellation Scutum RA 18h 50m 11s Dec –04 52’ 21”

Today Jupiter (Mag‒2.2) lies in the constellation of Virgo with the nice double star Gamma-Virginis --- Porrima --- to the upper right. RA 12h 50m 53.9s Dec -03° 57’ 19” Diameter 39.9.”  The longitude of the Great Red Spot is 270 degrees (System II) and will be visible on these dates.

Today Saturn (Mag 0.0) lies in the constellation of Ophiuchus RA 17h 36m 45.5s Dec -21° 58’ 16” Diameter 18.38”

Today Uranus (Mag +5.9) lies close to the star Omicron Piscium RA 01h 43m 04s Dec+10° 03’ 56.2”

Today Neptune (Mag +7.9) lies in the constellation Aquarius (Transit 05h 40m UT) RA 23h 03m 24” Dec -07 01’ 20.4”

ON THIS DAY: 12 JUNE 2017

All times are given in UT ‘Universal Time’

Comet C/2015 V2 Johnson is visible in a pair of 10x50 binoculars, and can be found in the constellation of Bootes, and moves south into Virgo on 15 June.

RA 14h 26m 42.2s

DEC +07 13’ 21”.

In addition, comet 289/P Blanpain Mag +20 is at opposition. It lies in the constellation of Ophiuchus just below the planet Saturn.

The Asteroid 1674 Groeneveld (Mag 16.9) Occults the 6.4 Mag star HIP 42516 which can be seen by amateur astronomers in Brazil and Peru. RA 08h 40m Dec -20° 00’ 27.6”

The Apollo class Asteroid 2017 KF3 (Mag 21) flies by the Earth at a distance of about 3 million miles. The Amor class Asteroid 397 Vienna (1894 BM) also flies by the Earth today at a distance of 161,650 million miles.

Today THE MOON lies in the constellation of Sagittarius RA 19h 16m35s Dec -19 06’ 55” Lunation 17.21 days, and is at minimum Libration (Size 5.5°) Position Angle 128° Latitude -03° 14’  Longitude –03 50’.

Today Mercury is visible in the morning sky 5° north of Aldebaran RA 04h 33m 04.2s Dec +21° 23’ 41” Mag -2.0 Diameter 5.38” Phase 0.893

Today Venus is at Aphelion. The planet (Mag -4.4) is also visible in the morning sky. RA 2h 16m 54.7s Dec +10° 58’ 10” Diameter 21.71” Phase 0.540.

Today Mars (Mag +1.7) lies in the constellation Gemini close to the open cluster M35 RA 06h 21m 18.2” Dec +24° 16’ 28” Diameter 3.65”. The planet is visible in the west after sunset.

The Asteroid Ceres was in conjunction with the Sun on 6 June

The Asteroid Juno (Mag +10) lies in the Constellation Scutum RA 18h 57m 16s Dec –04 54’ 11”

Today Jupiter (Mag‒2.2) lies in the constellation of Virgo with the nice double star Gamma-Virginis --- Porrima --- to the upper right. RA 12h 50m 50.2s Dec -03° 56’ 21” Diameter 39.9”

Today Saturn (Mag 0.0) lies in the constellation of Ophiuchus RA 17h 37m 23.6s Dec -21° 58’ 29” Diameter 18.38”

Today Uranus (Mag +5.9) lies close to the star Omicron Piscium RA 01h 42m 47s Dec+10° 02’ 19.3”

Today Neptune (Mag +7.9) lies in the constellation Aquarius (Transit 05h 40m) RA 23h 03m 23.7” Dec -07 01’ 21.3”

Killer Asteroid on Earth Collision Course May Lurk Among Shooting Stars

One of the largest and most famous annual meteor showers may have taken a sinister turn, as the risk of the shower heralding a large asteroid on a track to smash into Earth and cause untold devastation has become more and more significant, according to Czech astronomers.

The Astronomical Institute of the Czech Academy of Sciences came to their grim conclusions after observing the Taurid meteor shower, which appears twice a year in the night sky: once during the early summer and once around Halloween.

A meteor shower occurs when Earth's movements send it through a stream of cosmic debris. Typically, the meteoroids that would hit Earth either disintegrate or are shrunken to a tiny size by Earth's atmosphere.

"We performed careful analysis of 144 Taurid fireballs observed by new digital autonomous fireball observatories of the European Fireball Network displaced over Czech Republic at 13 stations, Austria and Slovakia in 2015, when the activity was enhanced," researchers said.

The brightest fireball studied "was caused by a body in excess of 1,000 kg (2,204 lb), which corresponds to diameter more than one meter. Based on orbital similarity, we argue that asteroids of several hundred meters in diameter are members of the Taurid new branch as well."

The good news is that the larger asteroids seem to be porous and fragile, meaning they're more likely to split apart and subsequently disintegrate when they enter Earth's atmosphere. However, there's no guarantee that will happen.

Many of the Taurids come from Encke, a comet that orbits the sun and has been slowly crumbling over the last 30,000 years. Some astronomers have suggested that the Tunguska event, when a 500-foot asteroid exploded a few miles off the ground and flattened 770 square miles of Siberian wilderness in 1908, was caused by a fragment of Encke. The explosion was comparable to that of a 20-megaton nuclear bomb and would have been cataclysmic had it hit a densely populated area.

Scientists just did something even Einstein didn’t think was possible

Researchers just confirmed a theory originally proposed by Albert Einstein nearly a century ago, and it’s something that even the famed physicist thought was impossible. A team of scientists led by Kailash Sahu has observed a gravitational phenomenon in which light from stars is bent as it makes its way past neighbouring stars, and will publish their report in the journal Science on June 9th. 

Einstein’s idea — that the gravitational pull of stars can actually manipulate light passing by from extreme distances — is commonly called “gravitational micro lensing.” The famous scientist never actually observed the effect, and had no proof that it indeed existed, but his knowledge of the effects of gravity told him it was not only possible, but likely. In 1936, he wrote in Science that, because of the distance between stars, “there is no hope of observing this phenomenon directly.”

Now, modern technology makes such an observation possible, and researchers have just confirmed that Einstein was indeed correct. That isn’t to say there was any doubt — examples of gravitation micro lensing have been detected in space before, but never in this context, as Einstein predicted, and never studied and measured in this way.

“When a star in the foreground passes exactly between us and a background star, gravitational micro lensing results in a perfectly circular ring of light – a so-called ‘Einstein ring.'” said Terry Oswalt, astronomer with Embry-Riddle Aeronautical University and chair of the Department of Physical Sciences. “The ring and its brightening were too small to be measured, but its asymmetry caused the distant star to appear off-centre from its true position,” Oswalt says. “This part of Einstein’s prediction is called ‘astrometric lensing’ and Sahu’s team was the first to observe it in a star other than the Sun.”

So what would Einstein think of this? “Einstein would be proud,” Oswalt said. “One of his key predictions has passed a very rigorous observational test.”

Celestial boondocks: Study supports the idea we live in a void

AUSTIN, Texas -- Cosmologically speaking, the Milky Way and its immediate neighbourhood are in the boondocks.

In a 2013 observational study, University of Wisconsin-Madison astronomer Amy Barger and her then-student Ryan Keenan showed that our galaxy, in the context of the large-scale structure of the universe, resides in an enormous void -- a region of space containing far fewer galaxies, stars and planets than expected.

Now, a new study by a UW-Madison undergraduate, also a student of Barger's, not only firms up the idea that we exist in one of the holes of the Swiss cheese structure of the cosmos, but helps ease the apparent disagreement or tension between different measurements of the Hubble Constant, the unit cosmologists use to describe the rate at which the universe is expanding today.

Results from the new study were presented here today (June 6, 2017) at a meeting of the American Astronomical Society.

The tension arises from the realization that different techniques astrophysicists employ to measure how fast the universe is expanding give different results. "No matter what technique you use, you should get the same value for the expansion rate of the universe today," explains Ben Hoscheit, the Wisconsin student presenting his analysis of the apparently much larger than average void that our galaxy resides in. "Fortunately, living in a void helps resolve this tension."

The reason for that is that a void -- with far more matter outside the void exerting a slightly larger gravitational pull -- will affect the Hubble Constant value one measures from a technique that uses relatively nearby supernovae, while it will have no effect on the value derived from a technique that uses the cosmic microwave background (CMB), the leftover light from the Big Bang.

The new Wisconsin report is part of the much bigger effort to better understand the large-scale structure of the universe. The structure of the cosmos is Swiss cheese-like in the sense that it is composed of "normal matter" in the form of voids and filaments. The filaments are made up of super clusters and clusters of galaxies, which in turn are composed of stars, gas, dust and planets. Dark matter and dark energy, which cannot yet be directly observed, are believed to comprise approximately 95 percent of the contents of the universe.

The void that contains the Milky Way, known as the KBC void for Keenan, Barger and the University of Hawaii's Lennox Cowie, is at least seven times as large as the average, with a radius measuring roughly 1 billion light years. To date, it is the largest void known to science. Hoscheit's new analysis, according to Barger, shows that Keenan's first estimations of the KBC void, which is shaped like a sphere with a shell of increasing thickness made up of galaxies, stars and other matter, are not ruled out by other observational constraints.

"It is often really hard to find consistent solutions between many different observations," says Barger, an observational cosmologist who also holds an affiliate graduate appointment at the University of Hawaii's Department of Physics and Astronomy. "What Ben has shown is that the density profile that Keenan measured is consistent with cosmological observables. One always wants to find consistency, or else there is a problem somewhere that needs to be resolved."

The bright light from a supernova explosion, where the distance to the galaxy that hosts the supernova is well established, is the "candle" of choice for astronomers measuring the accelerated expansion of the universe. Because those objects are relatively close to the Milky Way and because no matter where they explode in the observable universe, they do so with the same amount of energy, it provides a way to measure the Hubble Constant.

Alternatively, the cosmic microwave background is a way to probe the very early universe. "Photons from the CMB encode a baby picture of the very early universe," explains Hoscheit. "They show us that at that stage, the universe was surprisingly homogeneous. It was a hot, dense soup of photons, electrons and protons, showing only minute temperature differences across the sky. But, in fact, those tiny temperature differences are exactly what allow us to infer the Hubble Constant through this cosmic technique."

A direct comparison can thus be made, Hoscheit says, between the 'cosmic' determination of the Hubble Constant and the 'local' determination derived from observations of light from relatively nearby supernovae.

The new analysis made by Hoscheit, says Barger, shows that there are no current observational obstacles to the conclusion that the Milky Way resides in a very large void. As a bonus, she adds, the presence of the void can also resolve some of the discrepancies between techniques used to clock how fast the universe is expanding.

Aliens … No … Famous ‘WOW’ signal was caused by two comets

On 15 August 1977, the Ohio State University Radio Observatory detected a strong narrowband signal in the constellation Sagittarius (Sgr). The frequency of the signal, which matched  closely with the hydrogen line (1420.40575177 MHz), peaked at approximately 23:16:01 EDT. The signal was so strong that astronomer Jerry Ehman, who first spotted it, circled it in red pen and wrote "Wow!" in the margin. The "Wow! signal," as it would come to be known, became the best evidence ever obtained for extra-terrestrial life.At least, until now. One astronomer believes he's figured out what really caused the Wow! signal and—spoiler alert—it's not aliens.

On  the same date and time, comet 266P/Christensen was transiting in the vicinity where the “Wow!”

Signal was detected. The purpose of this investigation, therefore, was to collect and analyse  radio emission spectra and determine if comet 266P/Christensen and/or any other previously unknown  celestial body in the Solar System was the source of the 1977 “Wow!” Signal. This investigation, moreover, was designed to improve our understanding of the content and origin of the “Wow!’ Signal by determining if a neutral hydrogen cloud emitted from a short-period comet could be detected by a terrestrial radio telescope.

USE THIS LINK TO DOWN LOAD THE FULL SCIENCE PAPER

http://planetary-science.org/wp-content/uploads/2017/06/Paris_WAS_103_02.pdf

Astronomer Antonio Paris has been studying the Wow! signal for a long time. In 2016, he released a paper along with fellow astronomer Evan Davies suggesting that the signal could have been caused by a comet orbiting in the inner solar system. Specifically, the 2016 paper identified two comets, 266P/Christensen and P/2008 Y2 (Gibbs), that were both in the area where the Wow! signal was detected.

Both of these comets have large hydrogen clouds surrounding them that could produce the kind of signal detected in 1977. Paris spent about four months in late 2016 and early 2017 with a telescope pointed at comet 266P, and found strong signals of the same type as the Wow! signal.

Paris also examined several other similar comets and found the same type of hydrogen cloud and the same type of signal, which means that even if comet 266P wasn't the specific source of the Wow! signal, another comet is most likely the culprit.

This is bad news for anyone holding out hope that the Wow! signal would be aliens, but it's a solid conclusion to one of the biggest mysteries in astronomy. Now that we know comets can create these otherworldly signals, any future signals we get will have to be vetted much more carefully.

China's space telescope to observe 'big eaters' in universe

CHINA'S new space telescope to be launched soon will probe many mysteries of the universe, including the belching "big eaters" -- active galactic nuclei at the most remote edges of the universe.

Scientists have discovered that almost every galaxy has a supermassive black hole with a mass several million to several billion times that of the Sun at its centre. With their mighty gravitational attraction, the supermassive black holes engulf the surrounding gas and dust.

When a black hole swallows too much, the excess matter is converted into two jet-flows perpendicular to the accretion disk of the black hole, which is like a glutton with a bloated belly belching.

The jet-flows and accretion disk of the supermassive black hole generate X-ray radiation strong enough to travel billions of light years. These galaxies have very bright nuclei -- so bright the central region can be more luminous than the remaining galaxy. Scientists call them active galactic nuclei.

The Hard X-ray Modulation Telescope (HXMT), developed by Chinese scientists, will observe some active galactic nuclei.

"Since the active galactic nuclei are very far from the Earth, our telescope can only detect the brightest ones," says Zhang Shuangnan, lead scientist of HXMT and director of the Key Laboratory of Particle Astrophysics at the Chinese Academy of Sciences (CAS).

The big eaters are full of mysteries. Scientists have found the double jet phenomenon is very common in galaxies with active galactic nuclei, but they don't understand why supermassive black holes cannot engulf all the matter falling into them.

Supermassive black holes are very different from black holes of stellar mass, which are formed when very massive stars collapse at the end of their life cycles. Scientists are still not clear how supermassive black holes are formed and grow, which is a key to understanding the evolution of galaxies.

HXMT's observation is expected to help scientists see the core region close to the event horizon of supermassive black holes at the centre of active galaxies and gather information about the extremely strong gravitational fields, Zhang says.

Nation

China's space telescope to survey Milky Way

Many black holes and neutron stars are thought to be hidden in the Milky Way. Since they don't emit visible light, or are covered by dust, only X-ray telescopes can find them.

China will soon launch its first X-ray space telescope, the Hard X-ray Modulation Telescope (HXMT), with the aim of surveying the Milky Way to observe celestial sources of X-rays.

"Our space telescope has unique capabilities to observe high-energy celestial bodies such as black holes and neutron stars. We hope to use it to resolve mysteries such as the evolution of black holes and the strong magnetic fields of neutron stars," says Zhang Shuangnan, lead scientist of HXMT and director of the Key Laboratory of Particle Astrophysics at the Chinese Academy of Sciences (CAS).

"We are looking forward to discovering new activities of black holes and studying the state of neutron stars under extreme gravity and density conditions, and the physical laws under extreme magnetic fields. These studies are expected to bring new breakthroughs in physics," says Zhang.

Compared with X-ray astronomical satellites of other countries, HXMT has larger detection area, broader energy range and wider field of view. These give it advantages in observing black holes and neutron stars emitting bright X-rays, and it can more efficiently scan the galaxy, Zhang says.

The telescope will work on wide energy range from 1 to 250 keV, enabling it to complete many observation tasks previously requiring several satellites, according to Zhang.

Other satellites have already conducted sky surveys, and found many celestial sources of X-rays. However, the sources are often variable, and occasional intense flares can be missed in just one or two surveys, Zhang says.

New surveys can discover either new X-ray sources or new activities in known sources. So HXMT will repeatedly scan the Milky Way for active and variable celestial bodies emitting X-rays.

Zhang says other countries have launched about 10 X-ray satellites, but they have different advantages and therefore different observation focuses.

"There are so many black holes and neutron stars in the universe, but we don't have a thorough understanding of any of them. So we need new satellites to observe more," Zhang says.

The study of black holes and neutron stars is often conducted through observing X-ray binary systems. The X-ray emissions of these binary systems are the result of the compact object (such as black hole or neutron star) accreting matter from a companion regular star.

By analysing binary system X-ray radiation, astronomers can study compact objects such as black holes or neutrons stars.

How do the black holes or neutron stars accrete matter from companion stars? What causes X-ray flares? These are questions scientists want to answer, and China's new space telescope might help.

Lu Fangjun, chief designer of the payload of HXMT, says the space telescope will focus on the Galactic plane. If it finds any celestial body in a state of explosion, it will conduct high-precision pointed observation and joint multiband observation with other telescopes either in space or on the ground.

There are more black holes in the Universe than previously thought

Astronomers have found what looks to a fresh trove of supermassive black hole pairs, increasing the number of known pairs by about 50 percent, after new image analysis techniques were used to study two of our most detailed sky surveys.

Finding these black hole pairs is crucial to understanding more about how they form and how galaxies eventually collide, with the new findings giving astronomers five new pairs to analyse.

At the centre of the new research is the hunt for dual active galactic nuclei (AGN) - the technical term for what's formed when two supermassive black holes get caught in a death spiral after the collision of their respective galaxies.

These two black holes get closer and closer before eventually crashing into each other to form an even larger supermassive black hole, shooting out huge amounts of energy at the same time - or at least that's the current hypothesis.

Occasionally, the collision seems to send the resulting black hole speeding off through space, but that's another story.

The AGNs are formed from the massive amounts of gas and dust stirred up as a result of this black hole death spiral, causing the final, really supermassive black hole to be heavier.

Active galactic nuclei can form around any black hole, giving us a better chance of spotting them from Earth, but to understand how all this works, we need to find more of them.

"Our model of the universe tells us [AGNs] should be there, but we have failed miserably to find them," lead research Sara Ellison from the University of Victoria in Canada told New Scientist.

Ellison and her colleagues looked at the WISE All Sky Survey and the Sloan Digital Sky Survey for their work, hunting for signs of recent galaxy collisions as well as high readings from the infrared part of the spectrum, which indicates lots of dust.

Further confirmation was found from luminosity measurements taken by the Chandra X-ray Observatory. The new technique turned up five new examples of dual AGNs, to add to the nine that had already been confirmed by X-ray studies.

That's "a significant new haul", write the researchers, and there could be more on the way.

We should point out that the research has yet to go through the peer-review process, so further confirmation of the findings is needed before they're confirmed, but this could end up being a very useful way of detecting more of these AGNs.

Once astronomers know where they are, they can study how they evolve, and how the resulting supermassive black holes grow.

These AGNs could also teach us more about gravitational waves, another after-effect of a collision of two black holes: or at least they will when the shock reaches us, in tens of millions of years.

A Whole New Jupiter: First Science Results from NASA's Juno Mission

Early science results from NASA's Juno mission to Jupiter portray the largest planet in our solar system as a complex, gigantic, turbulent world, with Earth-sized polar cyclones, plunging storm systems that travel deep into the heart of the gas giant, and a mammoth, lumpy magnetic field that may indicate it was generated closer to the planet's surface than previously thought.

"We are excited to share these early discoveries, which help us better understand what makes Jupiter so fascinating," said Diane Brown, Juno program executive at NASA Headquarters in Washington. "It was a long trip to get to Jupiter, but these first results already demonstrate it was well worth the journey."

Juno launched on Aug. 5, 2011, entering Jupiter's orbit on July 4, 2016. The findings from the first data-collection pass, which flew within about 2,600 miles (4,200 kilometers) of Jupiter's swirling cloud tops on Aug. 27, are being published this week in two papers in the journal Science, as well as 44 papers in Geophysical Research Letters.

"We knew, going in, that Jupiter would throw us some curves," said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. "But now that we are here we are finding that Jupiter can throw the heat, as well as knuckleballs and sliders. There is so much going on here that we didn't expect that we have had to take a step back and begin to rethink of this as a whole new Jupiter."

Among the findings that challenge assumptions are those provided by Juno's imager, JunoCam. The images show both of Jupiter's poles are covered in Earth-sized swirling storms that are densely clustered and rubbing together.

"We're puzzled as to how they could be formed, how stable the configuration is, and why Jupiter's north pole doesn't look like the south pole," said Bolton. "We're questioning whether this is a dynamic system, and are we seeing just one stage, and over the next year, we're going to watch it disappear, or is this a stable configuration and these storms are circulating around one another?"

Another surprise comes from Juno's Microwave Radiometer (MWR), which samples the thermal microwave radiation from Jupiter's atmosphere, from the top of the ammonia clouds to deep within its atmosphere. The MWR data indicates that Jupiter's iconic belts and zones are mysterious, with the belt near the equator penetrating all the way down, while the belts and zones at other latitudes seem to evolve to other structures. The data suggest the ammonia is quite variable and continues to increase as far down as we can see with MWR, which is a few hundred miles or kilometres. 

Prior to the Juno mission, it was known that Jupiter had the most intense magnetic field in the solar system. Measurements of the massive planet's magnetosphere, from Juno's magnetometer investigation (MAG), indicate that Jupiter's magnetic field is even stronger than models expected, and more irregular in shape. MAG data indicates the magnetic field greatly exceeded expectations at 7.766 Gauss, about 10 times stronger than the strongest magnetic field found on Earth.

"Juno is giving us a view of the magnetic field close to Jupiter that we've never had before," said Jack Connerney, Juno deputy principal investigator and the lead for the mission's magnetic field investigation at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "Already we see that the magnetic field looks lumpy: it is stronger in some places and weaker in others. This uneven distribution suggests that the field might be generated by dynamo action closer to the surface, above the layer of metallic hydrogen. Every flyby we execute gets us closer to determining where and how Jupiter's dynamo works."

Juno also is designed to study the polar magnetosphere and the origin of Jupiter's powerful auroras -- its northern and southern lights. These auroral emissions are caused by particles that pick up energy, slamming into atmospheric molecules. Juno's initial observations indicate that the process seems to work differently at Jupiter than at Earth.

Juno is in a polar orbit around Jupiter, and the majority of each orbit is spent well away from the gas giant. But, once every 53 days, its trajectory approaches Jupiter from above its north pole, where it begins a two-hour transit (from pole to pole) flying north to south with its eight science instruments collecting data and its JunoCam public outreach camera snapping pictures. The download of six megabytes of data collected during the transit can take 1.5 days.

"Every 53 days, we go screaming by Jupiter, get doused by a fire hose of Jovian science, and there is always something new," said Bolton. "On our next flyby on July 11, we will fly directly over one of the most iconic features in the entire solar system -- one that every school kid knows -- Jupiter's Great Red Spot. If anybody is going to get to the bottom of what is going on below those mammoth swirling crimson cloud tops, it's Juno and her cloud-piercing science instruments."

NASA's Jet Propulsion Laboratory in Pasadena, California, manages the Juno mission for NASA. The principal investigator is Scott Bolton of the Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama, for the agency's Science Mission Directorate. Lockheed Martin Space Systems, in Denver, built the spacecraft.

Rainfall on Mars shaped the planet

At one stage in its history rain storms on Mars were so heavy – and the raindrops so large – that they changed the planet’s surface, carving valleys and altering the shape of meteorite impact craters, new research shows.

A paper by geologists Robert Craddock and Ralph Lorenz, published in the journal Icarus, suggests that over billions of years Mars’s atmospheric pressure fell, powering up the nature of its rainfall.

Soon after its formation around 4.5 billion years ago, atmospheric pressure on the red planet was around four bars. To compare, Earth’s is one.

At that pressure, Craddock and Lorenz say, rain would have looked more like mist. Raindrops could not have grown to more than three millimetres in diameter, and would not have penetrated the ground when they hit it.

Over deep time, however, the atmospheric pressure decreased to around 1.5 bars. This, combined with lower gravity than that of Earth, meant that raindrops as large as 7.3 millimetres across could form – substantially bigger than the 6.5 millimetre whoppers sometimes recorded on our own planet.

The geologists calculate that the intensity of big falls would have been only about 70% of those found on Earth, but would still have been easily strong enough to put a dent or two in the ground.

Indeed, they suggest that the falls would have overwhelmed the soil’s ability to absorb moisture, thus creating run-off currents that eventually formed valley networks and reshaped impact craters.

“We have shown that Mars would have seen some pretty big raindrops that would have been able to make more drastic changes to the surface,” comments Lorenz, from Johns Hopkins University in the US.

Craddock, who works at the Smithsonian Institute, adds that their paper represents the first time scientists have used physics to gain insight into the Martian climate.

“There will always be some unknowns, of course, such as how high a storm cloud may have risen into the Martian atmosphere, but we made efforts to apply the range of published variables for rainfall on Earth,” he adds.

“It’s unlikely that rainfall on early Mars would have been dramatically different than what's described in our paper.”

scientists now want to send a space probe to orbit Pluto

Humanity's first up-close look at Pluto was so intriguing that some researchers want to go back and spend a lot more time studying the icy world.

Late last month, 35 scientists met for 7 hours in Houston to discuss the basic blueprint and science goals of a potential Pluto orbiter mission. Such an effort would build upon the knowledge gained during the epic Pluto flyby performed in July 2015 by NASA's New Horizons probe.

Participants came away from the April 24 workshop fired up and committed to doing their best to make such a project happen, said New Horizons principal investigator Alan Stern, who was there. [Destination Pluto: NASA's New Horizons Mission in Pictures]

The meeting was reminiscent, Stern said, of New Horizons' earliest days: the late 1980s, when he and a few other people first raised the possibility of launching a flyby mission to Pluto.

"It felt a lot like that, but [with] a new generation of people," Stern, who's based at the Southwest Research Institute in Boulder, Colorado, told Space.com.

New Horizons' flyby revealed Pluto to be a stunningly diverse world with vast plains of nitrogen ice, 2-mile-high (3.2 kilometers) mountains of water ice and a wealth of other surface features. But the probe got just a fleeting look at the dwarf planet system while zooming by; an orbiter would linger and lift Pluto's veil even more, Stern said.

"You could map every square inch of the planet and its moons," he said. "It would be a scientific spectacular."

As the possible mission is currently envisioned, the orbiter would cruise around the Pluto system, using gravity assists from the dwarf planet's largest moon, Charon, to slingshot it here and there, Stern said. The strategy would be similar to that employed by NASA's Cassini spacecraft, which has shaped its path through the Saturn system over the years via flybys of the ringed planet's largest moon, Titan.

The current concept is therefore different from one Stern proposed shortly after New Horizons' flyby, which would have put a lander down on Charon.

With a Charon lander, "you're stuck looking at one side of Pluto," Stern said. (Charon and Pluto are tidally locked, meaning each world always shows the same face to the other.)

"And you can't get in superclose. You can't get down in the atmosphere," he added. "This, I think, is a better mission concept."

Though the mission would be Cassini-like, the Pluto orbiter itself would resemble NASA's Dawn probe, which is currently circling the dwarf planet Ceres, Stern said. Like Dawn, the Pluto probe would likely use electric propulsion and have a half-dozen science instruments, he said.

However, because the Pluto orbiter would be operating so far from the sun, it would rely on nuclear power to generate its electricity, rather than sunlight, as Dawn does, Stern added. And the price tag would be higher than Dawn's $467 million; the Pluto effort would probably qualify as a New Frontiers mission or a small flagship. (New Frontiers missions cost about $1 billion, whereas flagships run about $2 billion.)

Stern said a Pluto orbiter could get off the ground in the late 2020s or so. A 2030 launch would have ceremonial significance, coming on the 100th anniversary of Pluto's discovery, he added. The probe would spend seven or eight years journeying to the dwarf planet, then perhaps four or five years studying Pluto and its moons.

When the probe's work there was done, Stern said, the spacecraft could conceivably use one last Charon flyby to escape the Pluto system and head toward another object in the Kuiper Belt, the ring of frigid bodies beyond Neptune's orbit. (New Horizons is doing something similar; it's now headed for a Jan. 1, 2019, flyby of a small Kuiper Belt object called 2014 MU69.)

But a Pluto orbiter mission is a long way from becoming reality, Stern stressed. He said he and his fellow researchers aim to mature the concept in time for it to be considered during the next Planetary Science Decadal Survey, a U.S. National Research Council effort that sets exploration priorities for NASA every 10 years.

The next decadal survey will start in 2020, finish in 2022 and be published in 2023, Stern said.

"The curtain is opening," he said of the Pluto orbiter idea. "This thing is going to be a topic of discussion now for the next few years."

Scarborough Firm Invests in Pop-Up Planetarium

Exploring the celestial wonders above North Yorkshire is being made easier thanks to a £15,000 investment in a pop-up planetarium and two powerful portable telescopes by a Scarborough firm.

Hidden Horizons, which specialises in science and natural history-based tours including coastal fossil hunting, began running stargazing safaris in 2016 as part of the inaugural Dark Skies Festival run jointly by the North York Moors and Yorkshire Dales National Parks.

The success of the 2016 and this February’s Festivals led to a spike in visitor interest for eyeing the dark skies and a surge in bookings for Hidden Horizons’ celestial exploring events.

Now, aided by a 50% grant from the North York Moors National Park Authority and additional support from the Forestry Commission, Hidden Horizons has purchased an inflatable planetarium, solar telescope and one of the county’s largest publicly-accessible portable telescopes to meet the growing interest.

The portability of the equipment means the company can now bring the wonders of the universe to schools, pubs, hotels and other public and private venues right across the region.

The beauty of the planetarium, which spans four-metres in diameter and can accommodate up to 30 children or 20 adults, means that Hidden Horizons can run sessions even if the weather prevents trips outdoors.

During the day the powerful solar telescope will enable visitors to safely observe sunspots and dramatic flares while the night sky telescope will lead budding astronomers on a journey deep into the universe, with its ability to reveal up to 40,000 objects at any one time.

Andy Exton, director and astronomer for Hidden Horizons comments:

“We’re very fortunate to have a great, expansive dark skies area on our doorstep and people are catching on to this.

Increasing numbers of stargazing bookings are coming from visitors outside the region, from as far afield as Manchester, London and even Singapore, and so this investment will really boost our offer, particularly as it increases our flexibility to stage pop-up astronomy evenings at a huge variety of venues.”

You can contact them here

Catriona McLees, Head of Promotion and Tourism for the North York Moors National Park Authority adds:

“We were delighted to extend grant funding for this initiative as it is a great legacy of the Dark Skies Festival and taps into the nation’s growing enthusiasm for stargazing. It will also help support other tourism businesses by providing a further draw for people to visit and stay in the National Park particularly during those months when footfall tends to drop off.”

Spectacular Aurora display not over yet

Aurora hunters were treated to an unusually intense and widespread display of the Southern Lights over the weekend, and it's not over yet, says Otago University astronomer Ian Griffin.

The Aurora Australis, or the Southern Lights, were spotted all over the country - and as far north as Auckland.

 

Dr Griffin - who is also the Otago Museum director - told Morning Report it was a particularly intense display in Otago on Sunday night.

"This was quite an interesting display, I saw mostly greens, but other people who have got better eyes than me were seeing reds, but the photographs showed all the colours much better and there were some lovely purples in there as well. So it was a pretty stunning display, all told."

This week's display was caused by a large coronal hole on the sun, said Dr Griffin.

"It's basically a gap in the sun's magnetic field that starts spewing material towards the Earth - and it races towards the Earth at between 600 and 800 kilometres per second - and it's that material that interacts with the Earth's magnetic field and causes the atmosphere to glow.

"And that glow is the aurora, and the colour of the glow is different gases in the atmosphere, so the green glow is mainly oxygen and if you can see the red colour, that's nitrogen."

He said Sunday was unfortunately cloudy in Otago, but that he had seen some "brilliant' pictures of lights in Christchurch and Wellington, and even further north.

"One of the most amazing things was that somebody photographed it in Auckland, which is pretty incredible really, because to see the aurora that far north is very unusual. You may only see it in Auckland once every couple of years."

Dr Griffin said the current round of lights could continue for a few more days.

"It'll probably tail off, but if it's clear tonight, I would nip out and have a look."

RESEARCHERS PRODUCE DETAILED MAP OF POTENTIAL MARS ROVER LANDING SITE

Brown University researchers have published the most detailed geological history to date for a region of Mars known as Northeast Syrtis Major, a spot high on NASA's list of potential landing sites for its next Mars rover to be launched in 2020.

The region is home to a striking mineral diversity, including deposits that indicate a variety of past environments that could have hosted life. Using the highest resolution images available from NASA's Mars Reconnaissance Orbiter, the study maps the extent of those key mineral deposits across the surface and places them within the region's larger geological context.

"When we look at this in high resolution, we can see complicated geomorphic patterns and a diversity of minerals at the surface that I think is unlike anything we've ever seen on Mars," said Mike Bramble, a Ph.D. student at Brown who led the study, which is published in the journal Icarus. "Within a few kilometres, there's a huge spectrum of things you can see and they change very quickly."

If NASA ultimately decides to land at Northeast Syrtis, the work would help in providing a roadmap for the rover's journey.

"This is a foundational paper for considering this part of the planet as a potential landing site for the Mars 2020 rover," said Jack Mustard, a professor in Brown's Department of Earth, Environmental and Planetary Sciences and a co-author on the paper. "This represents an exceptional amount of work on Mike's part, really going into the key morphologic and spectroscopic datasets we need in order to understand what this region can tell us about the history of Mars if we explore it with a rover."

Northeast Syrtis sits between two giant Martian landforms—an impact crater 2,000 kilometres in diameter called the Isidis Basin, and a large volcano called Syrtis Major. The impact basin formed about 3.96 billion years ago, while lava flow from the volcano came later, about 3.7 billion years ago. Northeast Syrtis preserves the geological activity that occurred in the 250 million years between those two events. Billions of years of erosion, mostly from winds howling across the region into the Isidis lowlands, have exposed that history on the surface.

Within Northeast Syrtis are the mineral signatures of four distinct types of watery and potentially habitable past environments. Those minerals had been detected by prior research, but the new map shows in detail how they are distributed within the region's larger geological context. That helps constrain the mechanisms that may have formed them, and shows when they formed
relative to each other.

The lowest and the oldest layer exposed at Northeast Syrtis has the kind of clay minerals formed when rocks interact with water that has a fairly neutral pH. Next in the sequence are rocks containing kaolinite, a mineral formed by water percolating through soil. The next layer up contains spots where the mineral olivine has been altered to carbonate—an aqueous reaction that, on Earth, is known to provide chemical energy for bacterial colonies. The upper layers contain sulphate minerals, another sign of a watery, potentially life-sustaining environment.

Understanding the relative timing of these environments is critical, Mustard says. They occurred around the transition between the Noachian and Hesperian epochs—a time of profound environmental change on Mars.

"We know that these environments existed near this major pivot point in Mars history, and in mapping their context we know what came first, what came next and what came last," Mustard said. "So now if we're able to go there with a rover, we can sample rock on either side of that pivot point, which could help us understand the changes that occurred at that time, and test different hypotheses for the possibility of past life."

And finding signs of past life is the primary mission of the Mars2020 rover. NASA has held three workshops in which scientists debated the merits of various landing targets for the rover.

Mustard and Bramble have led the charge for Northeast Syrtis, which has come out near the top of the list at each workshop. Last February, NASA announced that the site is one of the final three under consideration.

Mustard and Bramble hope this latest work might inform NASA's decision, and ultimately help in planning the Mars2020 mission.

"As we turn our eyes to the next target for in situ exploration on the Martian surface," the researchers conclude, "no location offers better access of the gamut of geological processes active at Mars than Northeast Syrtis Major."

McDonald Observatory dedicates $40 million upgrade

The University’s McDonald Observatory in West Texas dedicated its $40 million telescope upgrade last week and is now performing an in-depth study of a mysterious force known as dark energy.

The upgrade gives McDonald’s 10-meter telescope the ability to create a 3-D map of the universe to study dark energy, a little understood concept that could explain the accelerating expansion of the universe.

Photo Credit: Courtesy of Ethan Tweedie Photography | Daily Texan Staff

The telescope, the world’s third largest in size, can now see light that is close to 12 billion years old and can view 120 times more of the night sky than it previously could. Not even the largest telescope in the world at the Kek Observatory in Hawaii has as large of a field of view.

“It is sort of one of a kind right now,” McDonald Observatory director Taft Armandroff said. “It’s going to allow us to study a lot of areas of astronomy that are on the cutting edge.”

The Observatory received funding from the State of Texas, other universities and private donors to add four new instruments to the telescope along with expanding its view and depth. Two of these instruments, high and low resolution spectrographs, will be used to study the light from both galaxies and individual stars, Armandroff said.

Another new instrument allows the telescope to see high red-shift galaxies, or galaxies that are 10 to 12 billion light years away and were formed shortly after the Big Bang, Armandroff said.

Finally, Armandroff said the telescope now has a habitable zone planet finder which detects wobbles in the movement of a star to see if it has any orbiting planets.

Together, these devices will help astronomers at the University and elsewhere create a 3-D map they can use to measure how fast the universe’s expansion is accelerating and thereby give them an idea as to what force might be causing it, astrophysics professor Karl Gebhardt said.

“It’s crazy exciting. No one has looked at the universe in this way in the past,” Gebhardt said. “We may redefine what gravity actually is, (or dark energy) could be something like a new type of particle.”

Already, students at the University are analysing the data the telescope collects each night. After nightfall in West Texas, the telescope collects information that is sent to a server that both undergraduate and graduate students have access to.

After a class with Gebhardt last semester, aerospace engineering senior Jamie McCullough began working with the McDonald Observatory data. Most of the time, McCullough analyses the data sent over to adjust the information based on how much light was hitting the telescope. McCullough has also been working on writing a code that will perform these calibrations automatically.

“The upgrade is fantastic, and there’s so much data coming off of it, and there’s so much potential for so much advancement,” McCullough said. “It’ll really just be exciting to see what comes of it.”

NASA Radar Spots Relatively Large Asteroid Prior to Flyby

Radar images of asteroid 2014 JO25 were obtained in the early morning hours on Tuesday, with NASA's 70-meter (230-foot) antenna at the Goldstone Deep Space Communications Complex in California. The images reveal a peanut-shaped asteroid that rotates about once every five hours. The images have resolutions as fine as 25 feet (7.5 meters) per pixel.

Asteroid 2014 JO25 was discovered in May 2014 by astronomers at the Catalina Sky Survey near Tucson, Arizona -- a project of NASA's Near-Earth Objects Observations Program in collaboration with the University of Arizona. The asteroid will fly safely past Earth on Wednesday at a distance of about 1.1 million miles (1.8 million kilometres), or about 4.6 times the distance from Earth to the moon. The encounter is the closest the object will have come to Earth in 400 years and will be its closest approach for at least the next 500 years.

"The asteroid has a contact binary structure - two lobes connected by a neck-like region," said Shantanu Naidu, a scientist from NASA's Jet Propulsion Laboratory in Pasadena, California, who led the Goldstone observations. "The images show flat facets, concavities and angular topography."

The largest of the asteroid's two lobes is estimated to be 2,000 feet (620 meters) across.

Radar observations of the asteroid also have been conducted at the National Science Foundation's Arecibo Observatory in Puerto Rico. Additional radar observations are being conducted at both Goldstone and Arecibo on April 19 20, and 21, and could provide images with even higher resolution.

Radar has been used to observe hundreds of asteroids. When these small, natural remnants of the formation of the solar system pass relatively close to Earth, deep space radar is a powerful technique for studying their sizes, shapes, rotation, surface features, and roughness, and for more precise determination of their orbital path.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages and operates NASA's Deep Space Network, including the Goldstone Solar System Radar, and hosts the Center for Near-Earth Object Studies for NASA's Near-Earth Object Observations Program within the agency's Science Mission Directorate.

Do Meteors Hiss, Sizzle, and Pop?

For hundreds of years there have been reports of people hearing the sound of meteors—shooting stars—as they streak across the sky. As early as 1714, astronomy Edmond Halley (yes, that Halley, of comet fame) dismissed these accounts of hissing, sizzling, and popping as figments of the imagination. After all, sound travels much more slowly than light—see: every thunderstorm ever—so any sound from the meteor breaking up in the atmosphere would arrive long after the streak of ionized gas has faded from the sky. But hearing and seeing a meteor at the same time is not a scientific impossibility. A new hypothesis published in Geophysical Research Letters might explain just how it happens, and why the described noises sound a lot like radio static.

When a meteor hits the atmosphere, at between 25,000 and 160,000 miles per hour, it releases electromagnetic radiation, including both light and what are known as very low frequency radio waves. Twenty-five years ago, scientists demonstrated that these waves, which travel just as fast as light, can cause objects, especially metal ones, to vibrate in a way that produces sound.

“The conversion from electromagnetic waves to sound waves … is exactly how your radio works,” Colin Price of Tel Aviv University, co-author of the new study, told Science. The study proposes that these waves come from an electrical current generated as the meteor interacts with the atmosphere. Though it involves coma ions, an am bipolar electric field, and Hall current, it’s the simplest explanation for the phenomenon yet.

Telescope project makes progress on radio-quiet zone

The Square Kilometre Array (SKA) SA project office has acquired half of the land it needs to create a radio-quiet zone around the large radio telescope and is on track to complete the process by the end of 2018, says spokesman Lorenzo Raynard.

It is an important milestone in a sensitive process as, if the farmers in the area refuse to sell their land, the government can expropriate it. The SKA is an international science project located in SA and Australia and will be the world’s most powerful radio telescope once completed. The South African core is 90km from Carnarvon in the Northern Cape.

About 131,500ha of land surrounding the telescope’s 176-dish core needs to be free from radio-frequency interference. The project acquired 13,500ha of this land in 2008. In 2016 it embarked on a process to acquire another 118,000ha comprising 36 parcels of land close to the core as well as access rights to servitudes that will hold another 21 dishes.

The SKA SA project office has acquired 14 parcels of land, comprising 61,000ha and needs to buy another 18 parcels of land totalling 57,000ha. Four parcels of land originally earmarked for purchase no longer needed to be bought, but would provide access rights to servitudes, said Raynard. The land-acquisition project is one of three SKA processes under way in SA. The Department of Science and Technology has been driving the implementation of legislation to protect the site from radio interference.

Why Sending Stephen Hawking to Space Matters

Despite having been told he would not make it past his 25th birthday, now 75-year-old renowned cosmologist and science author Stephen Hawking is being sent to space on billionaire Richard Branson’s Virgin Galactic ship. While confined to a wheelchair and communicating via a speech generator attached to a single cheek muscle, Stephen Hawking continues to contribute to the advancement of science in incredible ways. Over the course of his career, Hawking has also been a fierce advocate of disability rights and has shattered the glass ceiling of what people with disabilities are perceived to be capable of time and time again.

While the physical and intellectual capabilities of human beings differ greatly, they do not necessarily define us nor do they render us incapable of accomplishing significant feats. Stephen Hawking has visited one of Earth’s last thresholds, Antarctica, and has experienced weightlessness on a sub-orbital space flight. He is the Director of Research at the Centre for Theoretical Cosmology at the University of Cambridge and has written several novels, of which A Brief History of Time was a record-breaking best-seller. The physicist famously theorized that black holes emit radiation and is a recipient of the Presidential Medal of Freedom, the greatest award for civilians available in the United States. These are just a few of his accomplishments.

Hawking’s incredible career signifies the extent to which the empowerment of people with disabilities through increased accessibility and technological advancement can provide greater opportunities for everyone to pursue their dreams regardless of their circumstances. At age 21, Hawking was diagnosed with a rare early-onset form of amyotrophic lateral sclerosis (ALS) that has slowly paralyzed him. While this disease is generally fatal within five years, Hawking has lived more than five decades since his initial diagnosis. While not everyone diagnosed with ALS may have access to the same treatment and care as this academic celebrity, the longevity and success of Hawking’s career demonstrates that investing in people with disabilities is a worthy pursuit.

While Stephen Hawking’s physical capabilities have continued to decline over the decades, his mind and intellect have remained intact. By providing Hawking with a vehicle to communicate his brilliance, the pursuit of science has benefited as a whole. People with disabilities are often erased in both science and science fiction. Becoming a spacefaring species was one of the greatest defining moments for human beings. Now, we look to colonizing other terrestrial bodies in the event that one day our own planet can no longer harbour life.

In a visit to London’ Space Museum in 2015, Stephen Hawking stated that space travel “represents an important life insurance for our future survival, as it could prevent the disappearance of humanity by colonizing other planets.” One of the cosmologist’s biggest dreams has been to travel to space himself which will, in the near future, become a reality. As an icon for disability rights activism, Hawking’s journey will allow people with disabilities to see themselves represented in the voyage to the stars.

In science fiction, writers imagine future worlds in which anything is possible. In these imaginings of tomorrow, be they utopian, dystopian or complex, nuanced worlds with problems like our own, disability is often perceived as something to be cured, fixed or erased altogether. In pathologizing disability or removing it entirely from futurist contexts, people with disabilities often do not find themselves represented or as fitting into the grand scheme. As a result, Stephen Hawking’s projected spaceflight matters immensely as it exemplifies that he, like anyone else, is an individual with his own physical and intellectual capacities, of which having a disability is not his sole-defining characteristic.

It is evident that Hawking’s career has been greatly empowered due to his intelligence and access to economic capital which others with his disease may not be as fortunate to have. However, he is a shining example of the potential that can be realized when society works to develop technology and increase accessibility for everyone. Today, accessibility can take on the form of ensuring all stations on public transit lines have elevators or that all new buildings use levers instead of door knobs. The shift towards accessibility in urban planning and the design of all things means that people with disabilities have a bright future ahead.

The rise of space tourism by private companies like Virgin Galactic and SpaceX are disrupting the entire space exploration industry. The CEO of SpaceX, founder of PayPal and Tesla Motors’ Elon Musk has launched private vehicles into space and enabled them to return to Earth with reusable rockets. In doing so, Musk has greatly reduced the cost of spaceflight and in turn made it more accessible. As these companies continue to develop space technology, the goal of taking humans to other planets becomes more realistic. Not only this but also sending human beings to space from all walks of life including those, like Stephen Hawking, with disabilities.

Stephen Hawking being sent so space matters for every dreamer who has imagined themselves leaving Earth to gaze down in wonder upon the curvature of the pale blue dot. It has traditionally only been astronauts with unparalleled physical and intellectual ability who have had the enormous privilege of leaving our planet’s atmosphere. Now, the extremely wealthy can purchase a ticket to the stars via private space travel companies. However, as evidenced by this change and while it may take centuries, it is only a matter of time before space travel becomes available to everyone.