Parallax Effect Charted in the 2012 Transit of Venus

Combined images taken simultaneously (06 June 2012, 03:46:18 UTC) from Svalbard and Canberra, showing the Venus parallax effect from 2 different locations on Earth, separated by 11600km. Credit: Pérez Ayúcar/Breitfellner

Back in the 18th century, astronomers were trying to determine the distance from the Earth to the Sun. They used the parallax method during the Transits of Venus the 1760s to help answer that question, and their results provided a cosmic measuring stick that has allowed astronomers to measure distances in the Universe.

How did that method work? New images and movies of the transit of Venus on June 6, 2012 which compare event from two different locations on Earth clearly show the parallax effects that have made Venus transits so important historically.

The movies compress 6 hours of observations and 5,000 individual images taken by optical and solar telescopes into a 40 second video. Data gaps due to cloudy conditions produce jumps in the otherwise smooth Venus motion across the Sun disk. The observations were taken from Svalbard in Norway and Canberra in Australia, which are separated by 11,600 km (7,200 miles).

When the images from the two locations are compared, the parallax effect is obvious.

By knowing the distance between two observers on Earth and comparing the differences in their observations, astronomers were able to work out the distance from the Earth to Venus. And because of Johannes Kepler’s calculations, 18th century astronomers already knew Venus’ orbit is about 70 percent that of Earth’s. So by knowing the distance between the Earth and Venus, they were also able to figure out the value for the Astronomical Unit.

The images used in the movies were obtained by members of the European Space Astronomy Centre, which is located outside Madrid. Two of the observers, Miguel Pérez Ayúcar and Michel Breitfellner are on the science operations planning team for the Venus Express satellite, which has been orbiting Venus since 2006.

“During the hours of the transit we were delighted by the slow, delicate, gracious passage of Venus in front of the Sun,” Ayúcar said. “A perfect black circle, containing a world in it, moving in front of its looming parent star. How thankful we were to witness it. Now with these movies, we can share a sense of that experience.”

Breitfellner said, “In the 18th century people realized that transits of Venus could be used to measure the distance from the Earth to the Sun. Teams of astronomers were sent all across the world to measure this effect. The 2012 transit has its own historical importance – it is the first that has occurred when a spacecraft is in orbit at Venus. Science teams are now working to compare observations of the Venus transit from Earth with simultaneous observations from Venus Express.”

Colin Wilson, Operations Scientist for Venus Express, said, “Planetary transits are not just of historical interest, they have acquired a new importance in the study of newly discovered planets around other stars. Because we cannot image exoplanets directly, it is only by studying their transits that we can discover whether they harbour liquid water or other potential ‘biomarker’ molecules like methane or ozone. The Venus transit is an example much closer to home, offering us a chance to test our understanding of how to interpret transit data. This certainly added extra interest as we watched the Venus transit in June – particularly knowing it was our last chance that we’d have to wait until 2117 to see the next one!”

Transit of Venus 2012 from Svalbard and Canberra from Lightcurve Films on Vimeo.

Source: EPSC

The “Deep Blue Sea” of the Sun

Looking like an intricate pen-and-ink illustration, the complex and beautiful structures of the Sun’s surface come to life in yet another stunning photo by Alan Freidman, captured from the historic Mount Wilson Observatory near Los Angeles, California.

Click below for the full-size image in all its hydrogen alpha glory.

An oft-demonstrated master of solar photography, Alan took the image above while preparing for the transit of Venus on June 5 — which he also skillfully captured on camera (see a video below).

Hydrogen is the most abundant element found on the sun. The sun’s “surface” and the layer just above it — the photosphere and chromosphere, respectively — are regions where atomic hydrogen exists profusely in upper-state form. It’s these absorption layers that hydrogen alpha imaging reveals in detail.

The images above are “negatives”… check out a “positive” version of the same image here.

” The seeing was superb… definitely the best of the visit and among the best solar conditions I’ve ever experienced,” Alan writes on his blog.

The video below was made by Alan on June 5, showing Venus transiting the Sun while both passed behind a tower visible from the Observatory.

Alan’s work is always a treat… see more of his astrophotography on his website

Image © Alan Friedman. All rights reserved.

Transit of Venus Redux: More Great Images


Images and video from the Transit of Venus on June 5/6, 2012 are still pouring in, and we needed to share just a few more. Here’s an awesome close-up look at the event in Hydrogen Alpha from accomplished astrophotographer John Chumack. He used a Lunt Solar Scope 60mm/50F H-Alpha filter and a DMK 21AF04 Fire-wire camera. This is 741 frames & 1/91 second exposure. John has more images on our Flickr page, and on his website, Galactic Images.

Venus transit with a transit of B747 jumbo across the solar disk as seen from Elliots Beach, Madras, India. Credit: Muralikrishna Kanagala.

Venus transit with a transit of B747 jumbo across the solar disk which was captured by one of the members of the Tamilnadu Astronomical Society in India, Mr. Muralikrishna Kanagala during our transit event at Elliots Beach, Madras, India at 6.02 hrs IST, as the Sun rose. He used a Baader filtered Sony DSH H50 Camera.

An image of the June 2012 Venus Transit taken a few minutes after the transit maximum from Quezon City, Philippines. Credit: Raven Yu.

Patrick Cullis put together this amazing time-lapse of the Transit, which features two telescopes, an airplane transit, sunset, and a few different angles of the view.

Transit Sunrise with boat and bird joining the scene, as seen in Romania. Credit: Alex Conu.
Montage of sampling of images taken during Venus transit (very cloudy day!) from Morden, Manitoba, Canada. Credit: darethehair on Flickr.
Transit Sunrise from Iran. Credit: Khashayar Maroufi

The above video is from the Solar Dynamics Observatory, a composite of the entire Transit, set to music.

Transit of Venus as seen in South Carolina, USA. Credit: Blake and Orion Crosby.

And finally, this image and story from Blake Crosby and his son Orion from Charleston, South Carolina, displaying the lengths people would go to witness this event:

“This won’t be the best shot of the transit by a long shot, but my son and I jumped through a lot of hoops just to get it,” Crosby wrote in an email. “We live in Charleston, SC and our horizon is blocked by towering pine trees so we checked into the 9th floor of a Holiday Inn with a westward facing room. After lugging up all of our equipment, we found out that the doors to the balconies had been permanently closed, so we would have to shoot through a pane of glass with our Canon Rebel XS attached to a Celestron Nexstar 4SE with a Seymour filter. Furthermore, we were greeted, like many others, with a thick wall of clouds that just didn’t want to budge. Even worse, the hotel’s wifi was so shoddy we couldn’t stream any of the live views from the internet. However, we got a lucky break at about 8:00 EDT when the clouds parted for about 2 minutes and we were able to snap a couple of pics. My son Orion remarked that he was glad we endured those setbacks just so we could get a glimpse of an event that won’t happen again in our lifetimes.”

You can always see more images of many great astronomical views on our Flickr group page. Join us in sharing your images there and we may post them on Universe Today!

Clouds part for Transit of Venus from Princeton University


Despite a horrendous weather forecast, the clouds parted – at least partially – just in the nick of time for a massive crowd of astronomy and space enthusiasts gathered at Princeton University to see for themselves the dramatic start of the Transit of Venus shortly after 6 p.m. EDT as it arrived at and crossed the limb of the Sun.

And what a glorious view it was for the well over 500 kids, teenagers and adults who descended on the campus of Princeton University in Princeton, New Jersey for a viewing event jointly organized by the Astrophysics Dept and the Amateur Astronomers Association of Princeton (AAAP), the local astronomy club to which I belong.

See Transit of Venus astrophotos snapped from Princeton, above and below by Astrophotographer and Prof. Bob Vanderbei of Princeton U and a AAAP club member.

Transit of Venus snapped from Princeton University - full sized image
This photo was taken with a Questar telescope at 6:26 p.m. on June 5, 2012 - it’s a stack of eight - 2 second images. Stacking essentially eliminates the clouds. Hundreds attended the Transit of Venus observing event organized jointly by Princeton University Astrophysics Dept and telescopes provided by the Amateur Astronomers Association of Princeton (AAAP), local astronomy club. Credit: Robert Vanderbei

It was gratifying to see so many children and whole families come out at dinner time to witness this ultra rare celestial event with their own eyes – almost certainly a last-in-a-lifetime experience that won’t occur again for another 105 years until 2117. The crowd gathered on the roof of Princeton’s Engineering Dept. parking deck – see photos

Excited crowd witnesses last-in-a-lifetime Transit of Venus from campus rooftop on Princeton University. Onlookers gathered to view the rare Transit of Venus event using solar telescopes provided by the Amateur Astronomers Association of Princeton (AAAP) and solar glasses provided by NASA and lectures from Princeton University Astrophysics Dept.
Credit: Ken Kremer

For the next two and a half hours until sunset at around 8:30 p.m. EDT, we enjoyed spectacular glimpses as Venus slowly and methodically moved across the northern face of the sun as the racing clouds came and went on numerous occasions, delighting everyone up to the very end when Venus was a bit more than a third of the way through the solar transit.

Indeed the flittering clouds passing by in front of Venus and the Sun’s active disk made for an especially eerie, otherworldly and constantly changing scene for all who observed through about a dozen AAAP provided telescopes properly outfitted with special solar filters for safely viewing the sun.

Kids of all ages enjoy the Transit of Venus from a rooftop at Princeton University. Solar telescopes provided by the Amateur Astronomers Association of Princeton (AAAP), solar glasses provided by NASA and lectures from Princeton University Astrophysics Dept. Credit: Ken Kremer

As part of this public outreach program, NASA also sent me special solar glasses to hand out as a safe and alternative way to directly view the sun during all solar eclipses and transits through your very own eyes – but not optical aids such as cameras or telescopes.

Transit of Venus snapped from Princeton University - quarter sized image
This photo was taken with a Questar telescope at 6:26 p.m. on June 5, 2012 - it’s a stack of eight - 2 second images. Credit: Robert Vanderbei

Altogether the Transit lasted 6 hours and 40 minutes for those in the prime viewing locations such as Hawaii – from where NASA was streaming a live Transit of Venus webcast.

You should NEVER look directly at the sun through any telescopes or binoculars not equipped with special eye protection – because that can result in severe eye injury or permanent blindness!

We in Princeton were quite lucky to observe anything because other astro friends and fans in nearby areas such as Philadelphia, PA and Brooklyn, NY reported seeing absolutely nothing for this last-in-a-lifetime celestial event.

Transit of Venus enthusiasts view the solar transit from Princeton University rooftop using special solar glasses provided by NASA. Credit: Ken Kremer

Princeton’s Astrophysics Department organized a series of lectures prior to the observing sessions about the Transit of Venus and how NASA’s Kepler Space Telescope currently uses the transit method to detect and discover well over a thousand exoplanet and planet candidates – a few of which are the size of Earth and even as small as Mars, the Red Planet.

NASA’s Curiosity rover is currently speeding towards Mars for an August 6 landing in search of signs of life. Astronomers goal with Kepler’s transit detection method is to search for Earth-sized planets in the habitable zone that could potentially harbor life !

So, NASA and astronomers worldwide are using the Transit of Venus in a scientifically valuable way – beyond mere enjoyment – to help refine their planet hunting techniques.

Doing an outreach program for NASA, science writer Dr Ken Kremer distributes special glasses to view the transit of Venus across the sun during a viewing session on the top level of a parking garage at the E-quad at Princeton University to see the transit of Venus across the sun on Tuesday evening, June 5, 2012. Michael Mancuso/The Times

Historically, scientists used the Transit of Venus over the past few centuries to help determine the size of our Solar System.

See more event photos from the local daily – The Trenton Times – here

And those who stayed late after sunset – and while the Transit of Venus was still visibly ongoing elsewhere – were treated to an extra astronomical bonus – at 10:07 p.m. EDT the International Space Station (ISS) coincidentally flew overhead and was visible between more break in the clouds.

The International Space Station (ISS) flew over Princeton University at 10:07 p.m. on June 5 after the sun had set but while the Transit of Venus was still in progress. Credit: Ken Kremer
Transit Of Venus image from Hinode Spacecraft. Click to enlarge. Credit: JAXA/NASA/Lockheed Martin/enhanced by Marco Di Lorenzo

Of course clouds are no issue if you’re watching the Transit of Venus from the ISS or the Hinode spacecraft. See this Hinode Transit image published on APOD on June 9 and enhanced by Marco Di Lorenzo.

This week, local NY & NJ residents also had another extra special space treat – the chance to see another last-in-a-lifetime celestial event: The Transit of Space Shuttle Enterprise across the Manhattan Skyline on a seagoing voyage to her permanent new home at the Intrepid Sea, Air and Space Museum.

Ken Kremer

Thierry Legault: One Transit is Not Enough


Astrophotographer Thierry Legault had told us he was traveling to Australia for the Transit of Venus, so we knew he had something special planned. But that still didn’t prepare us for the awesomeness of what he has just achieved. During the Transit of Venus, Legault also captured the Hubble Space Telescope moving across the face of the Sun. Not once, but 9 times, during the HST’s transit time of .97 seconds. “Thanks to the continuous shooting mode of the Nikon D4 DSLR running at 10 fps,” Legault said on his website, which shows his new images. Of course, due to the differences in distance from Earth of Hubble vs. Venus, Venus took a lazy 6-plus hours to make its transit. A few giant sunspots also join in the view.

Below see a close-up of the two transits and a look at Legault’s set-up in the Outback of Queensland.

A close-up of Venus and Hubble (tiny black dots just above Venus) transiting the Sun. Credit: Thierry Legault. Used by permission.
Legault's equipment setup for viewing the Venus Transit in Queensland, Australia. Credit: Thierry Legault. Used by permission.

Legault noted that just one of the telescope/camera setups was his. So, he had just one chance of capturing the double transit. And he nailed it.

Here’s the map from CalSky of where the HST transit would be visible, just a thin band across the top of Queensland:

Map from CalSky of the Hubble Transit. Via Thierry Legault.

Legault said he has some more images on the way, including the ring of the atmosphere of Venus around the first contact, images of the transit in H-alpha, and the full ring of Venus 24 hours after the transit, so keep checking his website for more fantastic images.

Congratulations to Thierry Legault for a truly amazing and special capture of the Transit of Venus, something that won’t happen again in our lifetimes. And thanks to Thierry for sharing his images with Universe Today.

Stunning Timelapse: Spacecraft Capture the Transit of Venus

Here’s the entire 7-hour transit of Venus across the face of the Sun – shown in several views — in just 39 seconds, as seen by the Solar Dynamics Observatory on June 5, 2012. This view is in the 171 Angstrom wavelength, so note also the the bright active region in the northern solar hemisphere as Venus passes over, with beautiful coronal loops visible. The transit produced a silhouette of Venus on the Sun that no one alive today will likely see again. With its specialized instruments SDO’s high-definition view from space provides a solar spectacular!

Scott Wiessinger from NASA Goddard’s Scientific Visualization Studio wrote this morning to tell us, “If you have the space and the bandwidth, I really recommend downloading this large file on the SVS to view. YouTube compression is hard on solar footage, so it looks even better when you watch it at true full quality.”

Below is a composite image from SDO of Venus’ path across the Sun, as well as another great timelapse view from ESA’s PROBA-2 microsatellite:


This movie shows the transit of Venus as seen from SWAP, a Belgian solar imager onboard ESA’s PROBA2 microsatellite. SWAP, watching the Sun in EUV light, observes Venus as a small, black circle, obscuring the EUV light emitted from the solar outer atmosphere – the corona – from 19:45UT onwards (seen on the running timer on the video). At 22:16UT – Venus started its transit of the solar disk.

Venus appears to wobble thanks to the slight up-down motion of Proba-2 and the large distance between the satellite and the Sun.

The bright dots all over the image, looking almost like a snow storm, are energetic particles hitting the SWAP detector when PROBA2 crosses the South Atlantic Anomaly, a region where the protection of the Earth magnetic field against space radiation is known to be weaker.

And as if the Sun is just showing off, a Coronal Mass Ejection is visible as well towards the end of the video, seen as a big, dim inverted-U-shape moving away from the Sun towards the bottom-right corner. This is a coronal mass ejection bursting out from the Sun.

Venus Transit As Seen from the International Space Station


The guy known as Mr. Fixit in space was also Mr. Prepared. This image is from NASA Astronaut Don Pettit on board the International Space Station, who had the foresight to bring a solar filter for his camera. “I’ve been planning this for a while,” said Pettit. “I knew the Transit of Venus would occur during my rotation, so I brought a solar filter with me when my expedition left for the ISS in December 2011.”

This is his first image, and we’ll add more as they become available. Pettit is trying to download his images almost real-time. He is photographing the historic transit of Venus through the Space Station’s Cupola, removing the scratch panes on the Cupola’s windows to get crisp, clear images.

Pettit is using a high-end Nikon D2Xs camera and an 800mm lens with a full-aperture white light solar filter.

Transit of Venus: First Images


The transit of Venus across the face of the Sun — the last one for another 105 years — has begun! Here are some first images from various astrophotographers, telescopes, space missions. This first one comes from amateur astronomer Jason Melquist from Minneapolis, Minnesota USA taken just as Venus began its ingress into the Sun’s interior face.

See more below, and we’ll be adding images as they come in! And if you aren’t watching our live webcast, see it here.

This image from the Solar Dynamics Observatory has a definite ‘WOW!’ factor, with huge coronal loops just under Venus transiting the Sun:

Solar Dynamics Observatory image of the Venus transit with stunning coronal loops. Credit: NASA/SDO
An awesome shot of a plane transiting the Sun along with Venus. This is a cross view stereo pair and can be viewed in 3-D by the free fusion method. Credit: BillDavis6959 on Flickr
From the Solar Dynamics Observatory: Planet Venus transiting the Sun in the 304 Anstrom wavelength at approx. 90,000 degrees Fahrenheit. Credit: NASA/SDO

This one comes via Camilla SDO, the fearless mascot of the Solar Dynamics Observatory, who says of this image taken in 304 Angstrom wavelength, “This channel is especially good at showing areas where cooler dense plumes of plasma (filaments and prominences) are located above the visible surface of the Sun. Many of these features either can’t be seen or appear as dark lines in the other channels. The bright areas show places where the plasma has a high density.”

Below is a quick first movie from SDO of Venus’ ingress in 171 Angstrom!

And here’s SDO’s first “official” image of the transit, in 171 Anstrom wavelength:

Venus transit from the Solar Dynamics Observatory, the first view. Credit: NASA/SDO
View from Mike Phillips, who participated in Universe Today's live webcast feed. Credit: Mike Phillips.
Venus Transit and a few Sunspots, through passing clouds. Taken with Canon XTi/400D and hand-held Baader filter. Credit: Tavi Greiner.
Screenshot from the NASA Sun/Earth Day webcast feed, with telescopes using a red filter, via Beth Beck on Google+
Transit through the clouds. Credit: JCC_Starguy on Flickr.
Safe transit viewing setup by Jeremy Smith in Atlanta, Georgia, USA.

Jeremy Smith from Atlanta Georgia sent us views of his setup for ‘safe’ viewing of the transit. “My safe viewing rig is composed of a cheap tripod, a faulty rifle scope, three FedEx boxes and a FedEx mailer,” he said. “I got to see it with my daughter at home but we lost it behind the trees. We hightailed it to the local park but by the time we got there, it was a wash. We lost it behind clouds. The pictures of the transit didn’t turn out very well though. But I saw it!”

His view, below:

The 'safe' view of the Venus transit. Credit: Jeremy Smith
Venus continuing its transit of the Sun. Taken with a Megrez II 80mm, Thousand Oaks Optical Type 2+ White Light Glass Solar Filter and a Nikon 1 V1 camera with the 10-30 mm lens. Credit: Fernando Corrada
Transit of Venus photos taken from Matamata New Zealand as clouds allowed. Taken with filer on 400mm filter on Canon 60D. Credit: Alison Thomas

Want to get your Venus Transit image featured on Universe Today? Join our Flickr group, or send us your images by email (this means you’re giving us permission to post them). Please explain when you took it, the equipment you used, etc.

Tomorrow’s Transit Will be the First Photographed From Space


ESA astronaut Andre Kuipers captured this stunning image of Earth’s limb with Venus shining brightly above on the morning of June 4, 2012. While it’s a fantastic shot in its own right, it’s just a warm-up for tomorrow’s big transit event, which will be watched by millions of people all over the world — as well as a select few aboard the ISS!

While many people will be taking advantage of this last opportunity to see Venus pass across the face of the Sun — a relatively rare event that’s only happened six times since the invention of the telescope, and won’t occur again until 2117 — the crew of the International Space Station is preparing to become the first astronaut to photograph it from space!

Transit of Venus by NASA's TRACE spacecraft Image credit: NASA/LMSAL
Transit of Venus in 2004 by NASA's TRACE spacecraft. Image credit: NASA/LMSAL

Expedition 31 flight engineer Don Pettit knew he’d be up in orbit when this transit takes place, and he went prepared.

“I’ve been planning this for a while,” says Pettit. “I knew the Transit of Venus would occur during my rotation, so I brought a solar filter with me when my expedition left for the ISS in December 2011.”

(See more of Don Pettit’s in-orbit photography: Timelapse of a Moonrise Seen From The ISS)

Even though the 2004 transit happened while the ISS was manned, the crew then didn’t have filters through with to safely view it.

Pettit will be shooting the transit through the windows of the cupola. He’ll even be removing a scratch-resistant layer first, in order to get the sharpest, clearest images possible — only the third time that’s ever been done.

Don’s images should be — no pun intended — brilliant.

“I’ll be using a high-end Nikon D2Xs camera and an 800mm lens with a full-aperture white light solar filter,” he says.

And if you want to follow along with the transit as it’s seen from down here on Earth, be sure to tune in to Universe Today’s live broadcast on Tuesday, June 5 at 5 p.m. EDT where Fraser Cain will be hosting a marathon event along with guests Pamela Gay, Phil Plait (a.k.a. the Bad Astronomer) and more as live views are shared from around the world.

Unless you plan on being around in 2117, this will be your last chance to witness a transit of Venus!

Read more about Don Pettit’s photo op on NASA Science News here.

Book Review: Transit Of Venus: 1631 To The Present

Book review by David L. Hamilton

Dr. Nick Lomb’s book, “Transit Of Venus: 1631 To The Present,” covers the history of observed transits of Venus since the invention of the telescope in the early seventeenth century. The timing of the release of this book coincides with the upcoming transit of Venus, the last one that anyone alive today can witness due to the fact that the next transit will occur on December 2117. The upcoming transit will take place on June 5th or 6th of 2012, depending on your location, and Dr. Lomb’s book has a wealth of information on the times and locations across the globe from where one can observe the event.

During this transit, an observer on Earth can track the planet Venus as it crosses the disc of the Sun. One reason to track the transit of Venus is to get an accurate measurement of the size of our solar system. Although today we know the size of our solar, system Dr. Lomb’s book describes how this has not always been the case.

In the 1600’s Johannes Kepler, the famous German astronomer and astrologer, established the ratios of the distances of the known planets from the Sun. Knowing the ratios was a huge leap, however it did nothing to establish the size of our solar system. According to the text, if science could accurately determine the distance of a planet from the Sun, the distances of all the other planets could easily be known. Our adventure began once it was determined that timing the transit of a planet crossing the disc of the Sun from different locations on Earth would allow us to know the true size of our solar system.

Establishing the exact distance to the Sun was considered by Astronomer Royal Sir George Airy of the Greenwich Observatory in London “the noblest problem in astronomy.” The great nations of the time agreed and made arrangements to send out teams of scientists to the far reaches of the globe in hopes of attaining the required data.

Dr. Lomb covers each of the transits in detail by not only explaining the logistics involved in getting people and instruments to prime locations for observing the transits but also by providing a background story of those involved along with the triumphs and tragedies. When describing the people Lomb provides background information such as when they were born, their social and economic status, education, profession, and training, painting a clear picture of who the person really was and what their qualifications were. In addition to the background information, we are also presented with a detailed description of the preparations for the journey to remote sites across the globe including the adventures and misfortunes these individuals encountered along the way. This writing style provides for a connection with the adventures so one can appreciate the hardships endured to promote science by gaining and sharing knowledge about the world and universe that we live in.

The early transit expeditions were nothing short of an adventure. Lomb covers this well in the retelling of stories such as Charles Mason and Jeremiah Dixon’s journey to observe the transit. On this famous mission for the Royal Society, the ship carrying Mason and Dixon, the Seahorse, encountered the French warship, Le Grand. The end result of this encounter was the loss of 11 dead and almost 40 wounded. Needless to say, Mason and Dixon lost their nerve and informed the Royal Society that they were no longer interested in carrying out their duties, requiring persuasion in the form of threats to get them back on track. Mason and Dixon ended up at Cape Town instead of Bencoolen, Sumatra. Cape Town worked out well because the gentlemen had plenty of time to set up an observatory and calibrate instruments well before the day of the transit. Their measurements were so successful that they became well known and a few years later would be hired to survey a disputed boundary in the New World that would become famously known as the Mason-Dixon Line.

Whether it be Horrocks and Crabtree, Mason and Dixon, Le Gentil or Chappe, Lomb tells a story of ordinary humans doing the extraordinary in the name of science. Lomb reminds us that with success often comes failure. Consider, for example, the Frenchman Le Gentil who spent over 11 years chasing the transit across the globe, only to have it obscured by a cloud. Then he finally returned home to find out his estate was being squandered by those he had thought he could trust.

Lomb even describes how some gave their lives in the name of science. Consider the story of the Frenchman Chappe who understood the importance of getting an accurate timing of the transit in 1769. Despite imminent danger, Chappe stayed near San Jose del Cabo during the outbreak of a deadly epidemic that in the end cost him his life.

So, how does Lomb feel about these people and their willingness to lose everything, including in some cases, their lives, with the hopes of advancing scientific knowledge? “I greatly admire them for their willingness to set off for little known places and take risks in order to contribute to solving what was then the most crucial problem in astronomy,” Lomb told Universe Today via email. “Of course, we do need to realise that they lived in a world very different from ours: a world in which every journey was a boys’ own adventure, a world in which distant places were isolated, little known and genuinely different, and were only accessible after travel that was long and difficult.”

As for if there is anything comparable today, Lomb said the obvious comparison is with astronauts, especially those who first went into space and to the Moon. “Adventurous scientists today include volcanologists who travel to exotic places such as Papua New Guinea to study erupting volcanoes and storm chasers who fly into storms to study them,” Lomb said. “Possibly the best comparison to the astronomers of the 18th century are the scientists spending the dark and cold winter in Antarctica at places such as at the Amundsen-Scott South Pole Station so as to study the ice, the weather and to make astronomical observations from the driest place on Earth.”

In addition to the detailed stories, the book also contains a stunning collection of 140 photos and illustrations covering everything from high definition NASA images to drawings from the explorers themselves. The book also includes amazing images, maps and diagrams of the technologies used during the various transits.

Anyone interested in the upcoming transit of Venus will find this book to be a great resource for understanding the historical and scientific significance of the event along with valuable information to observe the event.

Find out more about the book here, or on Amazon.

Reviewer David Hamilton and his wife live in Conway, Arkansas. They are amateur astronomers that love spending nights stargazing. David is an Educational Technologist and Multidisciplinary researcher currently attending the University of Arkansas at Little Rock as a graduate student. David is an alumni of the University of Oklahoma and Rose State College.