Science

Arecibo Observatory's Greatest Triumphs – Gizmodo

Published

4 years ago

November 20, 2020

Harry Miller

The Arecibo Observatory in Puerto Rico.

Image: NAIC

Yesterday brought the tragic news that the famous 1,000-foot radio dish at the Arecibo Observatory in Puerto Rico will have to be demolished after the failure of two support cables. It’s the end of an era, but a good excuse to revisit some of the most important scientific contributions made possible by the famous facility.

Strategically built inside a sinkhole, the Arecibo Observatory has been at the center of all sorts of scientific breakthroughs for the past 57 years. The radio dish has made invaluable contributions to planetary and stellar science, the study of small-bodied objects like asteroids, cosmology, and even the search for extraterrestrial intelligence.

Here are some key highlights from Arecibo’s illustrious career. RIP.

NASA’s Mariner 10 spacecraft captured this photo of Mercury in 1974.

Arecibo’s first major discovery came in 1967, when data gathered by the radio telescope showed that a year on Mercury is 59 days long, not 88 days as previously assumed.

Visual demonstration of the message, with color added to distinguish the various sections.

A cool thing about the Arecibo Observatory is that, in addition to receiving radio signals, it can also transmit them. This capability was put to the test in 1974 when the facility beamed a transmission, known as the Arecibo message, to globular star cluster M13. This region of space is approximately 25,000 light-years away, so we’ll have to be patient about receiving a response.

Written in binary, the message was short, depicting things like DNA, the human form, and even a digital representation of the Arecibo Observatory itself. In case you’re wondering, here’s what the transmission looks like:

00000010101010000000000001010000010100000001001000100010001001011001010101010101010100100100000000000000000000000000000000000001100000000000000000001101000000000000000000011010000000000000000001010100000000000000000011111000000000000000000000000000000001100001110001100001100010000000000000110010000110100011000110000110101111101111101111101111100000000000000000000000000100000000000000000100000000000000000000000000001000000000000000001111110000000000000111110000000000000000000000011000011000011100011000100000001000000000100001101000011000111001101011111011111011111011111000000000000000000000000001000000110000000001000000000001100000000000000010000011000000000011111100000110000001111100000000001100000000000001000000001000000001000001000000110000000100000001100001100000010000000000110001000011000000000000000110011000000000000011000100001100000000011000011000000100000001000000100000000100000100000001100000000100010000000011000000001000100000000010000000100000100000001000000010000000100000000000011000000000110000000011000000000100011101011000000000001000000010000000000000010000011111000000000000100001011101001011011000000100111001001111111011100001110000011011100000000010100000111011001000000101000001111110010000001010000011000000100000110110000000000000000000000000000000000011100000100000000000000111010100010101010101001110000000001010101000000000000000010100000000000000111110000000000000000111111111000000000000111000000011100000000011000000000001100000001101000000000101100000110011000000011001100001000101000001010001000010001001000100100010000000010001010001000000000000100001000010000000000001000000000100000000000000100101000000000001111001111101001111000

You can find a full explanation of the Arecibo message here.

Pulsars—rapidly spinning stars that shoot beams of electromagnetic radiation from their highly magnetic poles—were first discovered in 1967. Researchers using the Arecibo Observatory in 1974 did one better by discovering the first binary pulsar, in which a pulsar orbits another star. The discovery earned Joseph Taylor and Russell Hulse the 1993 Nobel Prize in Physics.

In 1981, Arecibo provided the first radar maps of Venus—a planet perpetually covered in clouds. The dish would provide even more detail of Venus in the following years.

Asteroid 2001 GQ2, as imaged by the Arecibo in April 2001.

Arecibo spotted its first asteroid in 1989, an object named 4769 Castalia. The observatory would go on to find many more and collect important data about potentially dangerous near-Earth objects. One of the more regrettable aspects of the dish having to be shut down is that Arecibo will no longer scour the skies in search of potential threats.

Arecibo radar image showing ice at Mercury’s north pole.

The closest planet to the Sun, Mercury, has ice at both its north and south poles, which we learned in 1992 thanks to observations made by Arecibo. The deposits are presumably water ice, evidence of volatile materials on Mercury’s surface. This ice “persists in shadowed craters despite the high temperatures, 800°F, at the surface,” according to the National Astronomy and Ionosphere Center, which is the formal name of the Arecibo Observatory.

Artist’s impression of the first exoplanet ever discovered, which happens to orbit a pulsar.

In 1992, astronomer Aleksander Wolszczan used the Arecibo telescope to spot three exoplanets around a pulsar named PSR B1257+12. These were the first planets ever discovered outside of our solar system, and a big step forward in our understanding of the cosmos.

Artist’s impression of gravitational waves generated by binary neutron stars.

Gravitational waves—ripples in the fabric of spacetime caused by tremendous events like colliding black holes or supernovae—were finally confirmed by scientists in 2016, after being predicted by Albert Einstein a century ago. This monumental discovery, made by the Laser Interferometer Gravitational-wave Observatory (LIGO), might not have been possible had it not been for Arecibo, as NAIC explains:

Indeed, the first evidence for the existence of gravitational waves came from long-term Arecibo observations of a pulsar in a decaying orbit with another neutron star, where the rate of orbital shrinkage matched the rate expected from the loss of energy carried away by emitted gravitational waves.

Artist’s impression of a powerful X-ray burst erupting from a magnetar—a known source of fast radio bursts.

Scientists first detected fast radio bursts (FRBs) in 2007, but two major factors prevented them from fully understanding these enigmatic, millisecond-long pulses. The first is that all of them (until recently) originated in galaxies far, far away. The second is that FRBs were fleeting, one-off events. That changed in 2016, when scientists working at the Arecibo Observatory spotted the first repeating FRB. Since that time, we have detected other repeaters and even FRBs originating from our own galaxy. Recent evidence suggests these pulses are coming from highly magnetic neutron stars known as magnetars.

In one of the more unexpected astronomical discoveries, scientists used the facility to detect two rather odd pulsars that stopped blinking for intermittent periods. The discovery, made in 2017, suggests pulsars don’t always blink, and that they have an “on state” and an “off state.” What’s more, this research suggests there may be more intermittent pulsars than “normal” pulsars.

Despite these incredible discoveries, Arecibo is probably most famous for its use in SETI—the search for extraterrestrial intelligence. The observatory has been used by such groups as SETI@Home, the SETI team at the University of California, Berkeley, and the SETI Institute’s Project Phoenix. The dish was even featured in the 1997 film Contact. No radio signals from aliens have ever detected by Arecibo (nor by any other observatory, for that matter), which is, in and of itself, an interesting observation—one that’s forcing us to ask: Where is everybody?

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Science

The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

Published

7 days ago

September 13, 2024

Anne Joseph

NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.

Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.

She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.

Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.

“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.

It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.

Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.

Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.

Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.

“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.

He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

Published

1 week ago

September 11, 2024

Anne Joseph

TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

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B.C. sets up a panel on bear deaths, will review conservation officer training

Published

1 week ago

September 10, 2024

Anne Joseph

VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.

Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”

Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.

“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.

B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.

Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.

Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.

Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.

“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”

Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”

“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.

Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.

“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.

This report by The Canadian Press was first published Sept. 9, 2024.

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