Astronomy

The Moon, photographed from Space Shuttle Columbia on STS-107

The photo above shows a sight that can only be seen from space: The Moon against a black sky, with the Earth in daylight. Fewer than .00001% of the world’s population have had the opportunity to see this sight. That number will increase dramatically in the next few years, when suborbital spaceflight becomes commercially available.

At first glance, the Moon appears oddly dark. We think of the Moon as being quite bright, almost pure white. That’s because we’re used to viewing the Moon at night when our eyes are dark adapted. Of course, the Moon isn’t really white, or light in color, at all. The observations and photos taken by the Apollo astronauts, the samples they brought back, all prove that. Viewed alongside the oceans and clouds of Earth, the Moon shows its true color in this photograph.

The Moon also appears unusually small in this photo. That is due to the well-known Moon illusion, or rather the lack of a Moon illusion. When we observe the Moon in the night sky, our brains trick us into seeing the Moon as larger than it really is. That doesn’t happen when you look at a photograph of the Moon. The photo above is optically accurate, but the photo below has been altered to show the scene as you might actually perceive it from space, due to the Moon illusion:

Simulated Moon illusion

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Written by Astro1 on February 2nd, 2013 , Astronomy, Citizen Exploration

Record-Setting Asteroid Encounter

On February 15, an asteroid half the size of a football field will fly past Earth, only 17,200 miles above our planet’s surface.

This is the first time an object this large has been seen so close to Earth since NEO sky surveys began in the 1990′s.

Asteroid 2012 DA14 was discovered by amateur astronomers at the La Sagra Observatory in Spain on February 22, 2012. Orbital calculations show there’s no danger of 2012 DA14 actually hitting Earth, but it’s a pity we don’t have a quick-reaction sortie vehicle or tug that could get into position for a close look as it whizzes by. Such a vehicle would have a wide range commercial and military applications; the occassional rare science opportunity like this would be just an added bonus.

The Virtual Telescope Project will be holding a live coverage event starting at 22:00 Universal Time (5:00 PM EST, 2:00 PM PST) on February 15.

Written by Astro1 on January 28th, 2013 , Astronomy, Planetary Defense

Kepler Has Discovered 2740 Possible Planets

Today at the 221st American Astronomical Society meeting, the NASA Kepler space-telescope team announced 461 new planet candidates. The total number of planet candidates identified by Kepler now totals 2,740, including 351 Earth-sized candidates:

Four of the potential new planets are less than twice the size of Earth and orbit in their sun’s habitable zone, where liquid water might exist on the surface of a planet.

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Written by Astro1 on January 7th, 2013 , Astronomy

Citizen-Science Project Reports Another Confirmed Exoplanet

Planet Hunters has reported a second confirmed exoplanet discovery, along with 42 additional candidates and possible candidates.

Planet Hunters is an online project that allows citizen scientists to help find exoplanets in archived data from NASA’s Kepler space telescope. The new discovery, designated PH2-b, is a Jupiter-sized planet in the habitable zone of a Sun-like star. A paper on the discovery has been submitted to the Astrophysical Journal and made available to the public at arxiv.org.

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Written by Astro1 on January 6th, 2013 , Astronomy

“Britain’s National Hobby”

The Guardian reports that Great Britain has a new national hobby: amateur astronomy.

Membership and interest in astronomy and science clubs are said to be surging due to a popular BBC television program, Stargazing Live. Hosted by standup comic Dara Ó Briain (who also hosts Dara Ó Briain’s Science Club) and particle physicist Professor Brian Cox from the University of Manchester, the show attracts millions of viewers each week. It is now returning for its third year.

Stargazing Live is credited with saving the British General Certificate of Secondary Education in Astronomy from the scrap heap, as well as locating an undiscovered exoplanet during a live broadcast.

The show’s interest seems to parallel that of Cosmos, hosted by Dr. Carl Sagan, which was a popular phenomenon in the United States in the 1980′s. Cox has created Sagan’s Cosmos as being one of the major influences in his life. But unlike Sagan, who was dismissive of human spaceflight for most of his life, Cox and Ó Briain show an interest in doing more than just looking at space. On one episode, the hosts chatted live with the crew of the International Space Station. Another episode featured Apollo astronaut Gene Cernan talking about the Moon. According to Wikipedia, Cox gave his son George the middle name of “Eagle” after the Apollo 11 lunar module.

Stargazing Live once again disproves the myth that the public isn’t interested in space. Furthermore, this phenomenon is happening in Great Britain, which is often criticized for not having a manned space program. (It is frequently said that there has never been a British astronaut. For some reason, Dr. Helen Sharman doesn’t count.)

Stargazing Live also differs from Cosmos in one other respect. It urges viewers to go out and participate in amateur astronomy with their own hands and eyes. This message is well timed to fit in with the growing interest in citizen science.

Perhaps the Discovery Channel will take notice and produce similar shows for the United States. We’re getting really tired of lumberjacks, crab fishermen, and tattooed guys building motorcycles.

Written by Astro1 on January 6th, 2013 , Astronomy

Moore’s Law and SETI

An interesting comment from Dr. Gerry Harp, who recently succeeded Dr. Jill Tarter as director of the Center for SETI Research:

This endeavor is not as long a shot as people think. The technology is growing exponentially, especially signal processing, as computers are getting faster. Every six years our search speed is increased by a factor of 10. It’s not like we’re looking at star after star after star at the same rate.

This example shows that, contrary to certain “space cynics,” Moore’s Law of exponential growth can apply in space research.

Unfortunately, many space programs are still stuck in a pattern of slow (or even negative) arithmetic growth, due to political decisions that have kept NASA wedded to last-generation technologies and systems like Orion and JWST.

Written by Astro1 on December 28th, 2012 , Astrobiology, Astronomy

DARPA Seeks Amateur Help to Track Space Debris

At the Arizona Science and Astronomy Expo in Tucson, DARPA unveiled a new program to engage amateur astronomers in helping to protect satellites.

The goal of the program, called SpaceView, is to provide more diverse data to the Space Surveillance Network, a worldwide network of 29 radar and optical telescopes which observes and catalogues space objects to spot potential collisions. SpaceView plans to engage amateur astronomers by purchasing remote access existing amateur telescopes or providing telescopes to selected astronomers. The telescopes would still be available for amateur astronomy when not in use by the SpaceView program.

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Written by Astro1 on November 13th, 2012 , Astronomy, Planetary Defense

ESA Chooses Small Satellite for Exoplanet Mission

The European Space Agency has selected a Swiss proposal for funding as the first in a new class of small, low-cost science missions. Cheops (CHaracterising ExOPlanets Satellite) is planned for launch in 2017. The 30-cm (11.8-inch) telescope is designed for high-precision monitoring of a star’s brightness to detect planetary transits. Accurate transit measurements will allow scientists to determine the radius of transiting planets. It will also identify exoplanets with significant atmospheres.

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Written by Astro1 on October 19th, 2012 , Astronomy

Astronomy and In-Space Servicing

We recently compared NASA’s $8 billion James Webb Space Telescope to the European Extremely Large Telescope, which will provide 6 times the resolution at 1/6 the price.

Soon afterward, we received a note from former NASA scientist-astronaut Ed Gibson, who operated the Apollo Telescope Mount during the Skylab 4 mission. Dr. Gibson thought we had understated the case: “The E-ELT has a second advantage over the JWST’s lower resolution and light collection area; it can be serviced as required; the JWST, unlike the HST, cannot be serviced insitu.”

To be fair, NASA is studying some ideas for in-space servicing of JWST, using the Orion capsule and Space Launch System. Impartial observers do not consider those ideas to be credible, however. An Orion mission to the Earth-Sun L-2 point, where JWST is to be located, would cost a minimum of $2 billion, for the launch alone. That assumes Orion and SLS are already developed and available when they are needed.

Beyond the matter of cost, there are all sorts of technical obstacles. The JWST is not designed for in-space servicing. The Orion capsule is not designed to provide a stable work platform for servicing missions. The L-2 point is located 1.5 million miles from Earth. At that distance, the round-trip time lag for communications is 16 seconds, limiting the ability of mission control to provide ground support during EVAs.

The United States needs to develop its ability to do in-space servicing in Low Earth Orbit and, eventually, in deep space. That ability needs to be developed in a sensible manner, however. Astronauts have been doing in-space maintenance and repairs since Skylab. The challenge now is to make in-space servicing cost-effective. Some will say robots are the answer, but robots are not a magic bullet. The 16-second time lag for communications at L-2 is an impediment for humans but a killer for robots. We need to develop a range of servicing methods, both human and robotic, but we also need to develop the supporting infrastructure including low-cost transportation to orbit, low-cost transportation in orbit, and appropriate, cost-effective on-orbit facilities. Most of this infrastructure will be developed commercially in the decades to come.

For now, it appears that NASA is trying to tie two expensive programs – JWST and Orion/SLS – together. That’s a strategy NASA has employed successfully in the past, with programs like the Space Shuttle and Space Station. It’s a dangerous strategy, however, which makes it harder for Congress to cancel one program but drives up overall costs. If Congress ever becomes serious about saving money, both programs will be in danger.

Written by Astro1 on October 18th, 2012 , Astronomy, Space Policy and Management

Alpha Centauri B has Earth-sized Planet

European astronomers have discovered a planet with about the mass of the Earth orbiting the second star in the Alpha Centauri system. It is the smallest exoplanet yet discovered around a star like the Sun. The planet was discovered using the 3.6-meter telescope at the European Southern Observatory’s La Silla Observatory in Chile.

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Written by Astro1 on October 16th, 2012 , Astronomy, Space Policy and Management

Citizen Scientists Discover New Exoplanet

The citizen-science project planethunters.org has reported the discovery of a new circumbinary exoplanet, designated Planet Hunters 1 (PH1).

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Written by Astro1 on October 15th, 2012 , Astronomy

UK Infrared Telescope in Danger

Sky and Telescope reports that the United Kingdom Infrared Telescope (UKIRT) is in danger of being shut down if its owners can’t find a buyer to keep it in operation.

The UK Infrared Telescope is not exactly a backyard scope. The 3.8-meter (149-inch) instrument is the second-largest infrared telescope in the world and the largest in the northern hemisphere.

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Written by Astro1 on October 10th, 2012 , Astronomy, Space Policy and Management

Building an Extremely Large Telescope

This summer, the European Southern Observatory Council approved construction of the European Extremely Large Telescope. The E-ELT, to be sited on the Cerro Armazones mountain in the Atacama Desert of Chile, will be the largest optical/infrared telescope ever built. The primary diameter will be 39.3-meter (129-foot). Rather than a single mirror, the primary element will be an array of 798 1.4-meter (55-inch) mirrors.

The estimated cost for the mega-telescope, which is expected to see first light in 2022, is €1.055 billion ($1.36 billion at current exchanges rates).

American taxpayers should take note. That price is less than 1/6 the cost of NASA’s infrared James Webb Space Telescope (assuming JWST does not suffer any further cost overruns). Yet, the angular resolution of E-ELT at mid-infrared wavelengths will be six times better than JWST.

As we noted recently, advances in ground-based infrared astronomy are one reason why many astronomers are strangely unexcited about the JWST. The E-EELT is a good example of that.

The Europeans have also shown the willingness to sacrifice ultimate performance for the sake of cost-effectiveness. The size of the primary element was reduced from 42 meters, as originally planned, to save money and speed construction. This reduced the cost by 18%, from €1.275 billion to €1.055 billion, at the cost of 13% lower light sensitivity. Yet, astronomers are happy with the tradeoff because it enables the instrument to get built.

The construction plans for this telescope require almost 800 mirrors to be fabricated, then shipped separately to the top of the 3,064-meter (10,052-foot) peak.

There are risks in that plan, which will require a massive number of trucks. Perhaps one of the trucks will accidentally drive over a cliff, before the project is complete. With that many trucks, accidents are almost inevitable. Then, all of those mirrors must be assembled by workers under difficult conditions, at an altitude almost two miles above sea level. Working in parkas and mittens is uncomfortable. Studies show that workers in comfortable, air-conditioned factories at sea level are more efficient. Instead of trying to complete a massive construction project at that altitude, wouldn’t it be better to fabricate one huge monolithic mirror and develop a supertruck to transport it? Of course, no one has proposed such silliness. Yet, that’s the same “logic” used to justify developing superheavy lift rockets for space telescopes and other large space structures. We know how to make tradeoffs and compromises for the sake of cost-effectiveness on Earth, but never seem to do it for space projects.

Written by Astro1 on October 10th, 2012 , Astronomy, Space Policy and Management

Losing the Astronomical Arms Race

We were having lunch with an astronomer the other day when the subject of the James Webb Space Telescope came up. Somewhat to our surprise, he was not particularly interested in the JWST. Nor was his lack of interest simply due to the instrument’s enormous cost and uncertain schedule. He was much more excited more excited about the new PLANETS telescope being built in Hawaii.

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Written by Astro1 on September 30th, 2012 , Astronomy

Discovery Channel Telescope

The Discovery Channel has done a lot to make the public aware of the dangers of asteroid impacts, through numerous documentaries. Discovery Communications, which owns the Discovery Channel, is doing more than just scaremongering, though. Discovery has partnered with Lowell Observatory to build the 170-inch Discovery Channel Telescope, which saw first light in April of this year.

The Discovery Channel Telescope will spend part of its time looking for potentially dangerous near-Earth objects. It won’t be hunting alone, though. Planetary Resources and the B612 Foundation are planning space-based telescopes to search for near-Earth asteroids. It’s good to see so the private sector stepping up to the plate on this, since politicians have shown so little interest.

Written by Astro1 on September 15th, 2012 , Astronomy, Planetary Defense

Citizen Scientists Spot Jovian Blast

Spaceweather.com reports an explosion on Jupiter, which was detected by two amateur astronomers.

According to Spaceweather.com, the event occurred at 11:35 Universal Time on September 10. Dan Peterson of Racine, Wisconsin, observing through a 12-inch Meade telescope, observed a white flash lasting for 1.5-2 seconds. George Hall of Dallas, Texas was capturing a video of Jupiter at the time, which also captured the event.

It’s believed that the explosion was due to a comet or small asteroid collision. Similar events were observed in the past, in June and August 2010. These events underscore the continuing importance of amateur astronomy, as well as the need to discover potential impactors that could hit our own planet.

Written by Astro1 on September 11th, 2012 , Astronomy

Euclid’s Telescope

If there is an international space race (something we’re not at all certain of), the European Space Agency just made a strategic move to pass by approving construction of the Euclid space telescope.

Never mind the recent hype about China and thr first crewing of the Tiangong space station. Space races are mostly about public relations. Even Apollo was about PR. (You didn’t think landing Neil Armstrong on the Moon really affected the Cold War balance of power, did you?) The public doesn’t care much about the International Space Station, and there’s no reason to think the China’s (smaller, less capable) space station will generate any long-term interest, either. Ask most people what NASA’s greatest accomplishment is, and they’re more likely to say “Hubble” than “ISS.”

Hubble will be retired in a few years, however, and NASA has no plans for a replacement. No, we’re not forgetting JWST. The James Webb Space Telescope has been billed as a replacement for Hubble, but it isn’t. JWST is an infrared telescope; it won’t produce the sort of visible-light images that made Hubble so immensely popular. Once JWST is in orbit and the public realizes that fact, buyer’s remorse is likely to set in. We’re not sure NASA though this one through.

NASA recently took delivery of two Hubble-class telescopes originally built for the National Reconnaissance Office. Unfortunately, it can’t afford to launch either one of them due to JWST overruns and “monster rocket” expenditures eating up the NASA budget.

So, ESA’s approval of the Euclid space telescope is a timely move. With a 576-megapixel visible camera and optical resolution comparable to Hubble, Euclid will be positioned to take over Hubble’s role as the public’s favorite telescope. In government space programs, image is everything, and there’s little doubt Euclid will produce stunning images.

Still, it’s a bit disappointing to see a government space agency investing a billion dollars in a conventional Hubble replacement instead of pioneering new technology like optical interferometry. To misquote an old saying, give a man a telescope, and he will observe for a day; develop the technology to build better, cheaper telescopes, and he will observe for the rest of all time.

That’s one of the reasons Planetary Resources’ planned Arkyd-100 telescope constellation is so interesting. A large of number of relatively modest, but low-cost, space telescopes could be a game changer. A recent blog post from the company suggests Arkyd-100 may give amateur and professional astronomers the chance to take a directed picture of an object of their choice for just $100, compared to over $10,000 for other space telescopes.

Written by Astro1 on June 21st, 2012 , Astronomy, Innovation, Planetary Resources

Planetary Defense Requires Suborbital and Deep-Space Missions

NASA’s Near-Earth Object Observations Program is keeping a close eye on 2011 AG5, an Earth-crossing asteroid that could hit the Earth on February 5, 2040.

2011 AG5 is 140 meters in diameter. In the unlikely event of an impact, it would strike with the force of a 100-megaton bomb. NASA is sufficiently concerned that it held a Potentially Hazardous Asteroid Workshop at NASA Goddard Space Flight Center last month.

The probability of 2011 AG5 hitting Earth is currently estimated at 0.2%, but the estimate is still being refined. The probability will change when the asteroid passes through a gravitational keyhole on a pass by Earth in February 2023.

If 2011 AG5 is on a course toward Earth, further data could raise our certainty to 70%. Such data could be used to plan an intercept mission, which could occur either before or after the 2023 keyhole event.

Unfortunately, it’s currently impossible to observe 2011 AG5 because its relative position is too close to the Sun. It will not be possible for astronomers to observe 2011 AG5 again until fall of 2013.

Observing objects that appear close to the Sun will be one of the key missions for suborbital telescopes, such as the Atsa Suborbital Observatory which is slated to fly on the XCOR Lynx Mark III. The Atsa Observatory won’t be flying in time to help with the 2011 AG5 problem, but it will be valuable for studying similar asteroids in the future.

A robust plan for dealing with potentially hazardous asteroids will require a range of in-space capabilities, from suborbital observatories to deep-space intercept and deflection techniques.

Suborbital spacecraft are being developed in the private sector and do not require government investment – but what about the intercept and deflection problem?

Apollo 9 astronaut Rusty Schweickart, who created the B612 Foundation to develop asteroid-deflection techniques, does not think NASA is doing enough. Schweickart discusses 2011 AG5 and possible deflection techniques in the following video.

Written by Astro1 on June 18th, 2012 , Astronomy, Planetary Defense, XCOR Aerospace

Thoughts on “free” telescopes

A lot of people are scratching their heads trying to figure out the value, if any, of the two 2.4-meter Hubble-class telescopes recently donated to NASA by the National Reconnaissance Office.

As noted by Sky and Telescope, a Wide-Field Infrared Survey Telescope was one of the most important missions identified by the 2010 Astronomy and Astrophysics Decadal Survey. One or both of the NRO telescopes could fulfill that role.

Of course, a free telescope is like a free puppy. The telescopes currently lack both instrumentation and housekeeping, according to Sky and Telescope. And, of course, they require a ride to orbit.

These aren’t the only “free” telescopes to come out of the black world. There’s also a 120-inch (3-meter) Segmented Mirror Space Telescope which NRO donated to the Naval Postgraduate School.

What are the chances of NASA (or someone else) flying one of these telescopes?

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Written by Astro1 on June 8th, 2012 , Astronomy, Innovation

Lowell Amateur Research Initiative

The Lowell Oberservatory has created an Amateur Research Initiative. Lowell is seeking help from citizen scientists in several areas. Some projects require citizen scientists to have their own telescopes, while others can be performed only.

Projects that require telescopes include obtaining ultra-deep images of dwarf galaxies, creating light curves for slowly rotating asteroids, determining stellar rotation periods and finding stellar eclipses and giant planet transits, improving the orbits of Centaurs and Kuiper Belt Objects, and monitoring star-forming regions for outburst events.

Other projects include examining old image to find asteroids that were missed by an automated search; examining photometric data for signs of exoplanets, variables stars, or other transient objects; and identifying historic scientific instruments from the Lowell Observatory’s extensive collection.

Written by Astro1 on May 31st, 2012 , Astronomy

NASA privatizes space telescope

NASA has signed a Space Act agreement which turns the nine-year-old, $150-million Galaxy Evolution Explorer (Galex) ultraviolet space telescope over to the California Institute of Technology. Caltech will raise money from various sources to put the telescope back into operation.

Committed funders are the Keck Institute of Space Studies, a consortium of Israeli universities led by the Weizmann Institute of Science near Tel Aviv, Cornell University, and an international consortium that goes by the unwieldy name of GAMA/Herschel-Atlas/DINGO. Caltech is seeking additional funds from private donors, philanthropic foundations, and corporate sponsors.

If this Space Act is successful, it might provide a model for other space telescopes such as Hubble, which NASA plans to decommission in a few years. NASA plans to replace Hubble with the James Webb Space Telescope, but Webb is designed primarily for observations in the infrared, rather than visible wavelengths. There is likely to be some unhappiness when the public realizes that the visible-light images, which have made Hubble so popular, will be coming to an end. With the advent of low-cost launch and space servicing, it might be possible to keep space observatories like Hubble operational indefinitely. The question is, will the low-cost revolution come soon enough, or will Hubble be deorbited before it arrives, much as Skylab came down while waiting for the Shuttle to become operational?

Written by Astro1 on May 16th, 2012 , Astronomy

New citizen science project targets asteroids

A new citizen-science project from NASA is enlisting amateur astronomers to help discover near-Earth asteroids and study their characteristics.

The project, called Target Asteroids, will support NASA’s Origins Spectral Interpretation Resource Identification Security – Regolith Explorer (OSIRIS-REx) mission. OSIRIS-REx, which will study material from asteroid 1999 RQ36, is scheduled for launch in 2016.

Amateur astronomers participating in the project will help characterize the near-Earth asteroid population by recording their position, motion, rotation, and changes in brightness. Professional astronomers will use the information to refine theoretical models, improving their understanding of asteroids similar to the one OSIRIS-REx will encounter in 2019.

OSIRIS-REx will map the asteroid’s global properties, measure non-gravitational forces, and make observations that can be compared with data from telescopes on Earth. In 2023, OSIRIS-REx will return to Earth with 60 grams of surface material from the asteroid.

Previous observations indicate 1999 RQ36 is made of primitive materials. OSIRIS-REx data will provide new insights into the nature of the early solar system and the building blocks that led to life on Earth.

Amateur astronomers have provided tracking observations in support of NASA’s Near Earth Object Observation Program for more than 10 years. This traching data is important for selecting targets for asteroid missions such as OSIRIS-REx.

“Although few amateur astronomers have the capability to observe 1999 RQ36 itself, they do have the capability to observe other targets,” said Jason Dworkin, OSIRIS-REx project scientist at NASA’s Goddard Space Flight Center.

Partner organizations in the Target Asteroid program include the International Astronomical Search Collaboration, the Astronomical League, the Association of Lunar and Planetary Observers, Oceanside Photo and Telescope, the NASA Night Sky Network, the University of Arizona Mt. Lemmon SkyCenter, and the Catalina Sky Survey.

For more information on Target Asteroids, or to register for the program, click here.

Written by Astro1 on April 18th, 2012 , Astronomy, Planetary science Tags: asteroids

Mobile citizen science: Galaxy Zoo

Galaxy Zoo, the Zooniverse project that asks citizen scientists to help classify galaxies in Hubble Space Telescope images, has an iPhone app. Citizen scientists on the go can now classify galaxies on their iPhone (or iPad or iPod Touch).

You can download the Galaxy Zoo app from the App Store on iTunes. Galaxy Zoo also has an Android app available on Google Play.

Written by Astro1 on April 10th, 2012 , Astronomy

Large space telescopes: orbital assembly or superheavy lift?

There’s been considerable debate in the last few years about the relative merits of orbital assembly versus superheavy lift.

The argument for superheavy lift is pretty straightforward. Very large rockets enable payloads to be launched in one piece. Their advantage is not simply in the weight they can carry but, more importantly, in their large-diameter payload shrouds. Those very-large shrouds come in very handy for launching things like large-aperture telescope mirrors for future very large space telescopes.

In 2007, for example, NASA’s Marshall Space Flight Center did a study of how future space telescopes could be launched on the then-proposed Ares V rocket.

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Written by Astro1 on April 10th, 2012 , Astronomy

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