For most of human history, we could only see six planets: Mercury, Venus, Earth, Mars, Jupiter, and Saturn. The two outermost planets, Uranus and Neptune, were too far for early civilizations to see without a telescope. Uranus was the first planet to be discovered using a telescope. In 1781, the astronomer William Herschel discovered Uranus using a telescope. The discovery of Uranus inevitably led to the discovery of Neptune. The orbit of Uranus was complicated for astronomers to explain, and there were slight changes in it that could not be explained given the mass of Uranus and the other gas giants. To explain Uranus’s orbit, astronomers predicted the existence of another planet that orbited the Sun beyond Uranus. Neptune was first observed in 1846, confirming earlier predictions of its existence. This makes Neptune the only planet to be discovered using mathematics. With Uranus and Neptune, the solar system grew to include eight planets. However, the story wasn’t over.
The Ninth Planet
Neptune as Seen from the Surface of its Moon Triton
Like Uranus, the orbit of Neptune was slightly irregular. Given the calculated masses of Neptune and the other gas giants, the rotation of Neptune made little sense. Astronomers predicted that another planet must exist beyond the orbit of Neptune. For decades, astronomers surveyed the night sky searching for the ninth planet. Then, in 1930, astronomer Clyde Tombaugh discovered what was believed to be the ninth planet. Not only was it far beyond Neptune, but it was also very close to the predicted position of the ninth planet. It was called Pluto, and once again, the solar system’s family of planets grew. However, Pluto’s story was far from over. As it would later turn out, Pluto was far too small to explain the irregularities in Neptune’s orbit. Instead, Pluto may have been considered a planet, but its discovery was complete luck. When the Voyager 2 spacecraft completed its flyby of Neptune in 1989, it was revealed that the mass of Neptune was different from what astronomers had calculated. Once the correct mass of Neptune was accounted for, its orbit no longer contained irregularities. Despite this, Pluto would still be considered a planet until it was redefined as a dwarf planet in 2006. For the first time, the number of planets in the solar system shrunk.
Has The Solar System Always Had Eight Planets?
The Eight Planets in our Solar System Aligned Around the Sun
Today, the solar system contains eight planets. However, this has not always been the case. Shortly after the Sun formed and the planets began forming, a hundred or more planets were likely forming around the Sun. The early solar system existed in a state of utter chaos. The gravitational pull of so many planets made it difficult for them to find stable orbits. Instead, planets tugged on one another and would sometimes cross orbits. Occasionally, entire planets would collide. Depending on the mass of the planets and the angle at which the collision occurred, the larger planet would either absorb the smaller planet, or they would both break apart. It is generally believed that every planet in the solar system underwent one or more collisions with other planets. Even the Earth experienced a planetary collision around 4.5-billion years ago. A Mars-sized planet called Theia collided with the Earth at just the right angle that, rather than the two planets breaking apart, the young Earth absorbed Theia, and the debris from the collision went on to form the Earth’s moon.
The Return Of Planet Nine
The Most Color-Accurate Photo of Pluto Taken by NASA’s New Horizon’s Spacecraft in 2015
With Pluto’s demotion, many thought that the idea of a ninth planet in the solar system was dead. However, in the last decade, observational evidence has hinted at the existence of another planet far beyond the orbit of Neptune. In the far outer regions of the solar system, there exist countless comets, miklky w, and other forms of planetary debris in an area called the Kuiper Belt. While tracking the orbital path of some Kuiper Belt Objects (KBO), astronomers found some irregularities in their orbits. If a planet roughly 10-times the size of the Earth existed in the Kuiper Belt, it would explain the abnormalities observed in these orbits. If this hypothetical Planet Nine does exist, it will orbit the Sun roughly 400 times further than the Earth orbits the Sun. It would take Planet Nine thousands of years to complete one orbit around the Sun. As of yet, astronomers have found no definitive proof that Planet Nine exists.
It may seem strange that a planet within our solar system is hard to find. After all, scientists have uncovered thousands of planets outside the solar system, so why is it so difficult to find one within the solar system? Unfortunately for scientists, finding Planet Nine is no easy task if it even exists. Rather than being able to look inwards and use things like a star’s gravity or light to uncover a planet, scientists are looking outwards, trying to observe a planet that would receive virtually no sunlight. Planet Nine would also give off little to no heat, making it tremendously difficult to observe it in other wavelengths of light.
If there is a ninth planet in the solar system in the Kuiper Belt, it is unlikely it formed that far away from the Sun. Instead, it would have formed much closer and been pushed away by the other gas giants and planetary collisions. Perhaps a more intriguing hypothesis is that Planet Nine never actually formed in our solar system. It may have formed in a different solar system in the Milky Way, eventually being caught by the Sun’s gravity. This may seem strange, but a star can capture other planets. During the formation of a solar system, several planets may be flung outside their star’s gravity, becoming what are known as rogue planets. Some rogue planets may eventually find themselves close enough to another star to be captured by its gravity. The search for Planet Nine is ongoing, and if it does exist, its discovery will represent one of the most significant discoveries in the history of our solar system. As of yet, the solar system still contains eight planets.
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.
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.
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.”
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.
