Hubble Space Telescope

No Space Age for us

There’s a 500-word section on the Wikipedia page for the NASA Space Shuttle that describes the markings on the programme’s iconic orbiter vehicle (OV). Specifically, it talks about where the words ‘NASA’ and ‘USA’ appeared on the vehicle’s body, if there were any other markings, as well as some modifications to how the flag was positioned. Small-time trivia-hunters like myself love this sort of thing because, whether in my imagination or writing, being able to recall and describe these markings provides a strong sense of character to the OV, apart from making it more memorable to my readers as well as myself.

These are the symbols in our memories, the emblem of choices that weren’t dictated by engineering requirements but by human wants, ambitions. And it’s important to remember that these signatures exist and even more so to remember them because of what they signify: ownership, belonging, identity.

Then again, the markings on an OV are a part of its visual identity. A majority of humans have not seen the OV take off and land, and there are many of us who can’t remember what that looked like on TV either. For us, the visual identity and its attendant shapes and colours may not be very cathartic – but we are also among those who have consumed information of these fascinating, awe-inspiring vehicles through news articles, podcasts, archival footage, etc., on the internet. There are feelings attached to some vague recollections of a name; we recall feats as well as some kind of character, as if the name belonged to a human. We remember where we were, what we were doing when the first flights of iconic missions took off. We use the triggers of our nostalgia to personalise our histories. Using some symbol or other, we forge a connection and make it ours.

This ourness is precisely what is lost, rather effectively diluted, through the use of bad metaphors, through ignorance and through silence. Great technology and great communication strive in opposite directions: the former is responsible, though in only an insentient and mechanistic way, for underscoring the distance – technological as much as physical – between starlight and the human eye that recognises it; the latter hopes to make us forget that distance. And in the absence of communication, our knowledge becomes clogged with noise and the facile beauty of our machines; without our symbols, we don’t see the imprints of humanity in the night sky but only our loneliness.

Such considerations are far removed from our daily lives. We don’t stop (okay, maybe Dennis Overbye does) to think about what our journalism needs to demand from history-making institutions – such as the Indian Space Research Organisation (ISRO) – apart from the precise details of those important moments. We don’t question the foundations of their glories as much as enquire after the glories themselves. We don’t engender the creation of sanctions against long-term equitable and sustainable growth. We thump our chests when probes are navigated to Mars on a Hollywood budget but we’re not outraged when only one scientific result has come of it. We are gratuitous with our praise even when all we’re processing are second-handed tidbits. We are proud of ISRO’s being removed from bureaucratic interference and, somehow, we are okay with ISRO giving access only to those journalists who have endeared themselves by reproducing press releases for two decades.

There’s no legislation that even says all knowledge generated by ISRO lies in the public domain. Irrespective of it being unlikely that ISRO will pursue legal action against me, I do deserve the right to use ISRO’s findings unto my private ends without anxiety. I’m reminded every once in a while that I, or one of my colleagues, could get into trouble for reusing images of the IRNSS launches from isro.gov.in in a didactic video we made at The Wire (or even the image at the top of this piece). At the same time, many of us are proponents of the open access, open science and open knowledge movements.

We remember the multiwavelength astronomy satellite launched in September 2015 as “India’s Hubble” – which only serves to remind us how much smaller the ASTROSAT is than its American counterpart. How many of you know that one of the ASTROSAT instruments is one of the world’s best at studying gamma-ray bursts? We discover, like hungry dogs, ISRO’s first tests of a proto-RLV as “India’s space shuttle”; when, and if, we do have the RLV in 2030, wouldn’t we be thrilled to know that there is something wonderful about it not just of national provenance but of Indian provenance, too?

Instead, what we are beginning to see is that India – with its strapped-on space programme – is emulating its predecessors, reliving jubilations from a previous age. We see that there is no more of an Indianess in them as much as there is an HDR recap of American and Soviet aspirations. Without communication, without the symbols of its progress being bandied about, without pride (and just a little bit of arrogance thrown in), it is becoming increasingly harder through the decades for us – as journalists or otherwise – to lay claim to something, a scrap of paper, a scrap of attitude, that will make a part of the Space Age feel like our own.

At some point, I fear we will miss the starlight for the distance in between.

Update: We are more concerned for our machines than for our dreams. Hardly anyone is helping put together the bigger picture; hardly anyone is taking control of what we will remember, leaving us to pick up on piecemeal details, to piece together a fragmented, disjointed memory of what ISRO used to be. There is no freedom in making up your version of a moment in history. There needs to be more information; there need to be souvenirs and memorabilia; and the onus of making them needs to be not on the consumers of this culture but the producers.

Ways of seeing

A lot of the physics of 2015 was about how the ways in which we study the natural world had been improved or were improving.

Hubble turned 25
Half of the JWST’s mirrors got ready (with no more delays announced ahead of its 2018 launch)
The Udaipur Solar Observatory came online
ISRO launched ASTROSAT
The Foldscope gained popularity
The LHC restarted (and even delivered an exciting preliminary result)
Nature Methods declared cryo-electron microscopy to be its ‘method of the year‘ (paywall)
BARC’s MACE gamma-ray telescope was installed in Hanle, Ladakh
SESAME in Jordan got one-step closer to completion
On the downside, the TMT might not come to be

The pitfalls of thinking that ASTROSAT will be ‘India’s Hubble’

The Hubble Space Telescope needs no introduction. It’s become well known for its stunning images of nebulae and star-fields, and it wouldn’t be amiss to say the telescope has even become synonymous with images of strange beauty often from distant cosmic shores. No doubt saying something is like the Hubble Space Telescope simplifies the task of communicating that object’s potential and significance, especially in astronomy, and also places the object in stellar company and effortlessly elevates its public perception.

It’s for the latter reason that the comparison shouldn’t be made lightly. Not all telescopes are or can be like the Hubble Space Telescope, which sports some of the more cutting-edge engineering at play in modern telescopy, undoubtedly necessary to produce some of the images it produces (here’s a list of stunners). The telescope also highlighted the role of aestheticism in science: humans may be how the universe realises itself but the scope of that realisation has been expanded by the Hubble Space Telescope. At the same time, it has become so famous for its discoveries that we often pay no heed to the sophisticated physics at play in its photographic capabilities, in return for images so improbable that the photography has become irrelevant to our realisation of their truth.

ASTROSAT, on the other hand, is an orbiting telescope whose launch on September 28 will place India in the small cohort of countries that have a space-borne observatory. That’s insufficient to claim ASTROSAT will be akin to the Hubble as much as it will be India’s debut on the road toward developing “Hubble-class” telescopes. ASTROSAT’s primary science objectives are:

Understand high-energy processes in binary systems
Search for black hole sources in the galaxy
Measure magnetic fields of neutron stars
Study high-energy processes in extra-galactic systems
Detect new transient X-ray sources
Perform limited high angular-resolution deep field survey in UV

The repeated mentions of high-energy are synonymous with the parts of the electromagnetic spectrum ASTROSAT will study – X-ray and ultraviolet emissions have higher frequencies and thus higher energies. In fact, its LAXPC (Large Area X-ray Proportional Counter) instrument will be superior to the NASA NuSTAR X-ray telescope: both will be logging X-ray emissions corresponding to the 6-79 keV* energy range but LAXPC’s collecting area will be almost 10x the collecting area of NuSTAR’s. Similarly, ASTROSAT’s UV instrument, the Ultraviolet Imaging Telescope, studies wavelengths of radiation from 130 nm to 320 nm, like the Cosmic Origins Spectrograph on board the Hubble spans 115-320 nm. COS has a better angular and spectral resolution but UVIT, as well as the Scanning Sky Monitor that looks for transient X-ray sources, tops with a higher field of view. The UVIT and LAXPC double up as visible-wavelength detectors as well.

In contrast, the Hubble makes observations in the infrared, visible and UV parts of the spectrum. Its defining feature is a 2.4-m wide hyperbolic mirror that serves to ‘collect’ photons from a wide field of view onto a secondary hyperbolic mirror, which in turn focuses into the various instruments (the Ritchey-Chrétien design). ASTROSAT also has a primary collecting mirror; it is 30 cm wide.

Design of a Ritchey–Chrétien telescope. Credit: HHahn/Wikimedia Commons, CC BY-SA 3.0

But it’s quite wrong to think ASTROSAT could be like Hubble when you consider two kinds of gaps between the instruments. The first is the technical-maturity gap. Calling ASTROSAT “India’s Hubble” will imply that ISRO has reached that level of engineering capability when it has not. And making that reference repeatedly (here, here, here and here) will only foster complacency about defining the scale and scope of future missions. One of ISRO’s principal limitations is payload mass: the PSLV rocket has been the more reliable launch vehicle at our disposal and it can lift 3,250 kg to the low-Earth orbit. The GSLV rocket can lift 5,000 kg to the low-Earth orbit (10,000 kg if an upper cryogenic stage is used) but is less reliable, although promising. So, the ASTROSAT weighs 1,500 kg while the Hubble weighs 11,110 kg – the heaviest scientific satellite launched till date.

A major consequence of having such a limitation is that the technology gets to define what satellite is launched when instead of astronomers laying out what they want to find out and technology setting out to achieve it, which could be a useful impetus for innovation. These are still early days for ISRO but it’s useful to keep in mind even this component of the Hubble’s Hubbleness. In 1974, NASA and ESA began collaborating to build the Hubble. But before it was launched in 1990, planning for the James Webb Space Telescope (JWST) – conceived from the beginning to be Hubble’s successor – began in the 1980s. In 1986, an engineer named Pierre Bely published a paper outlining how the successor will have to have a 10-m primary mirror (more than 4x the width of the Hubble’s primary mirror) and be placed in the geostationary orbit so Earth doesn’t occlude its view of space, like it does for the Hubble. But even four years later, NASA didn’t have a launch vehicle that could heft 6,500 kg (JWST’s weight) to the geostationary transfer orbit. In 2018, Europe’s Ariane 5 (ECA) will be doing the honours.

The other is the public-outreach gap. As historian Patrick McCray has repeatedly noted, telescopes are astronomers’ central research tools and the quality of astronomy research is a reflection of how good the telescopes are. This doesn’t just mean large reflecting mirrors, powerful lenses and – as it happens – heavy-lift launch vehicles but also the publication of raw data in an accessible and searchable format, regular public engagement and, most importantly, effective communication of discoveries and their significance. There was a hint of ISRO pulling off good public outreach before the Mars Orbiter Mission launched in November 2013 but that evaporated soon after. Such communication is important to secure public support, political consensus and priority funding for future missions that can expand an existing telescope’s work. For the perfect example of what a lack of public support can do, look no further than the India-based Neutrino Observatory. NASA, on the other hand, has been celebrated for its social media efforts.

And for it, NASA’s missions are more readily recognisable than ISRO’s missions, at least among people who’ve not been following ISRO’s launches closely since the 1960s. Not only that, while it was easier for NASA’s scientists to keep the JWST project from being cancelled, due to multiple cost overruns, thanks to how much its ‘predecessor’ the Hubble had redefined the images of modern astronomy since the late 1990s, the Hubble’s infamous spherical aberration fault in its first years actually delayed the approval of the JWST. McCray writes in a 2009 essay titled ‘Early Development of the Next Generation Space Telescope‘ (the name of JWST before it was changed in 2002),

Years before the Hubble Space Telescope was launched in 1990 a number of astronomers and engineers in the US and Europe were thinking hard about a possible successor to the HST as well as working to engage a broad community of researchers in the design of such a new observatory. That the launch of any such successor was likely to be many years away was also widely accepted. However, the fiasco of Hubble’s spherical aberration had a serious effect on the pace at which plans were advancing for the Next Generation Space Telescope. Thus crucially for the dynamics of building the “Next Big Machine,” the fate of the offspring was intimately tied to that of the parent. In fact, … it was only when in the mid-1990s that the NGST planning was remade by the incorporation of a series of technology developments in infrared astronomy that NASA threw its institutional weight and money behind the development of a Next Generation Space Telescope.

But even for all the aestheticism at play, ISRO can’t be said to have launched instruments capable of transcending their technical specifications, either: most of them have been weather- and resource-monitoring probes and not crafted for the purpose of uncovering elegance as much as keeping an eye out. But that doesn’t mean, say, the technical specifications of the ASTROSAT payload shouldn’t be readily available, that there shouldn’t be one single page on which one can find all info. on ISRO missions (segregated by type: telecom, weather-monitoring, meteorology, resource-monitoring, astronomy, commercial), that there shouldn’t be a channel through which to access the raw data from its science missions**, or that ISRO continue to languish in its misguided conflation of autonomy and opacity. It enjoys a relative abundance of the former, and does not have to fight for resources in order to actualise missions it designs based on internal priorities. On the other hand, it’s also on the cusp of making a habit of celebrating frugality***, which could in principle provide the political administration with an excuse to deny increased funding in the future, and surely make for a bad idea in such an industry that mandates thoroughness to the point of redundancy as space. So, the day ought to come when the bright minds of ISRO are forced to fight and missions are chosen based on a contentious process.

There are multiple ways to claim to be the Hubble – but ASTROSAT is definitely not “India’s Hubble”. ISRO could in fact banish this impression by advertising ASTROSAT’s raw specs instead of letting people abide by inadequate metaphors: an amazing UV imager, a top-notch X-rays detector, a first class optical observer. A comparison with the Hubble also diminishes the ASTROSAT by exposing itself to be not like the Hubble at all and, next, by excluding from conversation the dozens of other space-borne observatories that it has already bested. It is more exciting to think that with ASTROSAT, ISRO is just getting started, not finished.

*LAXPC will actually be logging in the range 3-79 keV.

**There appears to be one under construction.

***How long before someone compares ASTROSAT’s Rs.178 crore to the Hubble’s $2.5 billion?

Of small steps and giant leaps of collective imagination

The Wire
July 16, 2015

Is the M5 star cluster really out there? Credit: HST/ESA/NASA

We may all harbour a gene that moves us to explore and find new realms of experience but the physical act of discovery has become far removed from the first principles of physics.

At 6.23 am on Wednesday, when a signal from the New Horizons probe near Pluto reached a giant antenna in Madrid, cheers went up around the world – with their epicentre focused on the Applied Physics Laboratory in Maryland, USA.

And the moment it received the signal, the antenna’s computer also relayed a message through the Internet that updated a webpage showing the world that New Horizons had phoned home. NASA TV was broadcasting a scene of celebration at the APL and Twitter was going berserk as usual. Subtract these instruments of communication and the memory of humankind’s rendezvous with Pluto on the morning of July 15 (IST) is delivered not by the bridge of logic but a leap of faith.

In a memorable article in Nature in 2012, the physicist Daniel Sarewitz made an argument that highlighted the strength and importance of good science communication in building scientific knowledge. Sarewitz contended that it was impossible for anyone but trained theoretical physicists to understand what the Higgs boson really was, how the Higgs mechanism that underpins it worked, or how any of them had been discovered at the Large Hadron Collider earlier that year. The reason, he said, was that a large part of high-energy physics is entirely mathematical, devoid of any physical counterparts, and explores nature in states the human condition could never physically encounter.

As a result, without the full knowledge of the mathematics involved, any lay person’s conviction in the existence of the Higgs boson would be punctured here and there with gaps in knowledge – gaps the person will be continuously ignoring in favour of the faith placed in the integrity of thousands of scientists and engineers working at the LHC, and in the comprehensibility of science writing. In other words, most people on the planet won’t know the Higgs boson exists but they’ll believe it does.

Such modularisation of knowledge – into blocks of information we know exist and other blocks we believe exist – becomes more apparent the greater the interaction with sophisticated technology. And paradoxically, the more we are insulated from it, the easier it is to enjoy its findings.

Consider the example of the Hubble space telescope, rightly called one of the greatest astronomical implements to have ever been devised by humankind.

Its impressive suite of five instruments, highly polished mirrors and advanced housing all enable it to see the universe in visible-to-ultraviolet light in exquisite detail. Its opaque engineering is inaccessible to most but this gap in public knowledge has been compensated many times over by the richness of its observations. In a sense, we no longer concern ourselves with how the telescope works because we have drunk our fill with what it has seen of the universe for us – a vast, multihued space filled with the light of a trillion stars. What Hubble has seen makes us comfortable conflating belief and knowledge.

The farther our gaze strays from home, the more we will become reliant on technology that is beyond the average person’s intellect to comprehend, on rules of physics that are increasingly removed from first principles, on science communication that is able to devise cleverer abstractions. Whether we like it or not, our experience, and memory, of exploration is becoming more belief-ridden.

Like the Hubble, then, has New Horizons entered a phase of transience, too? Not yet. Its Long-Range Reconnaissance Imager has captured spectacular images of Pluto, but none yet quite so spectacular as to mask our reliance on non-human actors to obtain them. We know the probe exists because the method of broadcasting an electromagnetic signal is somewhat easily understood, but then again most of us only believe that the probe is functioning normally. And this will increasingly be the case with the smaller scales we want to explore and the larger distances we want to travel.

Space probes have always been sophisticated bits of equipment but with the Internet – especially when NASA TV, DSN Now and Twitter are the prioritised channels of worldwide information dissemination – there is a perpetual yet dissonant reminder of our reliance on technology, a reminder of the Voyager Moment of our times being a celebration of technological prowess rather than exploratory zeal.

Our moment was in fact a radio signal reaching Madrid, a barely romantic event. None of this is a lament but only a recognition of the growing discernibility of the gaps in our knowledge, of our isolation by chasms of entangled 1s and 0s from the greatest achievements of our times. To be sure, the ultimate benefactor is science but one that is increasingly built upon a body of evidence that is far too specialised to become something that can be treasured equally by all of us.

Hubble at 25: My picks

For the Hubble space telescope’s 25th anniversary (April 24, 2015), NASA released a picture of the Westerlund 2 star cluster that the telescope shot. The image shows an expanding shell of gas lit up by the radiation from a cluster of 3,000 stars at its center.

On the occasion of a quarter-century of operations, here are my favorite pics shot by Hubble, arranged in no particular order (the number below each title is the object’s distance from Earth). However, the ‘Pillars of Creation’ is difficult to surpass in awesomeness, so let’s start with that.

Pillars of Creation
6,500 lightyears

The Pillars of Creation. Credit: NASA/ESA

First shot by Hubble in 1995, the Pillars of Creation is arguably the telescope’s most iconic snap, and Hubble has shot more than its share of those. The pillars are four-lightyear long columns of gas and dust blown outward by a cluster of energetic stars in the Eagle Nebula, and they’re also nursing young stars within themselves.

Sombrero Galaxy
28 million light years

Known and named for its resemblance to the Mexican hat, the Sombrero Galaxy is quite the looker for its nearly side-on appearance in this picture and for the beautiful halo enveloping it. It also has a noticeably pronounced dust-lane rimming its circumference. Finally, like the Milky Way, the Sombrero is thought to house a large black hole at its center.

Horsehead Nebula
1,500 lightyears

In the stupendous sequence of graphics depicting the origins of life in the universe in Terrence Malick’s Tree of Life, the Horsehead Nebula makes an appearance presumably because, like the Pillars of Creation, it’s an object made famous by Hubble’s snaps of it. Though its contours bear a distinct resemblance to the head of a horse, they will be eroded in a few million years by the radiation from a nearby massive star, Sigma Orionis.

Butterfly Nebula
2,100 lightyears

The Butterfly Nebula is actually a planetary nebula, a misleading name that stuck to identify the violent expulsion of its uppermost layers by a dying star. In between the two ‘wings’ of irradiated gas is a torus of dust 10-times as wide as the orbit of Pluto. At its center is a pair of stars, one of which is doing the dying and heating its surroundings to 250,000 degrees Celsius.

Jupiter
588 million km

Jupiter as seen by the Hubble space telescope. Credit: NASA/ESA

This picture – shot in April 2014 – is a favorite because it does well to show that despite being the largest planet in the Solar System, Jupiter’s also the least fully-formed. The fluidic bands of gases circulating at various latitudes bear testimony to that. For another, Hubble’s snap also shows the Great Red Spot – a violent storm larger than Earth that has been churning for at least 150 years – is shrinking.

Messier 5
25,000 lightyears

The Messier 5 globular cluster. Credit: NASA/ESA

Messier 5 is a massive cluster of 100,000 stars, packed in a volume of space 165-lightyears in diameter due to their own gravitation. It inhabits Milky Way’s halo; however, it is much older, hosting some stars that are over 13 billion years old. M5 gets its name from being the fifth in a famous catalog of astronomical objects compiled by the French astronomer Charles Messier in 1771.

Orion Nebula
1,500 lightyears

A personal favorite, the Orion Nebula is a very large star-forming region not too far from Earth, its location best identified by the belt of three stars. The chaotic spread of gases and dust is sculpted by the birth of over 700 stars at the moment, each in different stages of formation. The nebula itself is part of a much bigger gas cloud that includes the Horsehead Nebula. This view was snapped up by Hubble with some help from the ESO’s La Silla telescope. Click on it for a very-high-resolution version.

NGC 1672
60 million lightyears

A spiral galaxy like the Milky Way, NGC 1672’s claim to fame is a Hubble image in which it throws up many features that have seldom been spotted at once, in exquisite detail. Tentacular lanes of dust are visible to the left; a dense bar of stars cuts through the galaxy’s center; clumps of blue indicate hot star-forming regions; and a bright nucleus betrays the presence of a black hole.

AM 0644-741
300 million lightyears

The ring galaxy AM 0644-741. Credit: NASA/ESA

AM 0644-741 has an odd composition: a wide ring of stars (150,000 lightyears in diameter) surrounding a highly condensed cloud of gas and dust, with a lot of space in between. Astronomers have reason to believe the shape is the result of a cosmic collision between two galaxies. When the smaller galaxy passed into the larger one, the incursion of all that mass provided a focal point at which the interstellar matter in the vicinity gathered.