The joy of my life, my granddaughter Scarlet, asked me the other day, “Poppy, how big is the universe?”
Her boundless curiosity never ceases to amaze me. I attempted to explain to her, as best I could to an eight-year-old who has never travelled further than Halifax, N.S., that the universe, as we currently understand it, is very large – so large, in fact, that we have to measure it, not in terms of kilometers, but, rather, in light-years. Even then, the numbers are extremely big.
I am not sure my explanation of exactly what a light-year is (how far light travels through space in the course of one year, or approximately 9.5 trillion kilometers), and, how when multiplied by how far (in light-years) we can see out into space, did much to answer her initial query, as the resulting silence and quizzical expression on her face told me she couldn’t really grasp such distances (who can blame her?).
Her response just about summed up what, I imagine, most people would say: “Guess that really is pretty big, isn’t it, Poppy?”
“Yes, my darling, it certainly is,” I replied.
In the 1920s, the American astronomer, Edwin Hubble (after whom the Hubble Space Telescope is named) and his assistant, Milton Humason, proved that the galaxies they were studying and photographing were, in fact, moving outward as viewed from Earth, or receding, into deep space, and further, that the more distant the galaxy, the faster it was receding. This became known as Hubble’s Law.
Hubble’s discovery actually grew out of earlier work by Albert Einstein, who, in 1917, predicted that the universe was expanding, because space itself was expanding. Although, at the time, Einstein wasn’t confident enough in his expanding universe theory to publish it, it later formed the basis for his famous General Theory of Relativity.
When I use the term “universe” here, I mean the observable universe, the farthest point that we can see out into space with our best astronomical telescope – the Hubble Space Telescope (HST). In 2016, the HST photographed what, to date, is the most distant object – the galaxy GN-z11. Taking the expansion of the universe into consideration, it is approximately 32 billion light-years, or approximately 3.04 sextillion (3.04 followed by 21 zeros) kilometers away; a truly mind-boggling distance.
However, astronomers theorize that the actual universe is much, much larger. Starting at the moment of the universe’s theoretical creation (called the “Big Bang”, though not an actual explosion), the accepted age of the universe is now thought to be approximately 13.8 billion years. As the universe continues to expand, the most distant point in space from which we will ultimately receive light back from distant galaxies (which are increasingly moving away from us), known as the “cosmic horizon”, is estimated to be about 46 billion light-years away.
It is theorized that, due to the increasingly rapid rate of expansion of the universe as a whole, we will never see any light from objects beyond the cosmic horizon. However, when the James Webb telescope (a much larger and more sophisticated telescope than the HST) is launched on Oct. 31, 2021, the boundaries of the known universe will, undoubtedly, be extended.
Though the above distance figures are truly mind-blowing. and may make you feel incredibly small, it should, at the very least, underscore just how unique our life-bearing planet Earth is in the great infinite vastness of the cosmos and how wonderfully precious it is to have children and grandchildren who challenge you to think about it.
This week’s sky
Mercury remains too close to the sun to be visible this coming week. Venus (magnitude -4.2) is visible, as it has been these past few weeks, in the pre-dawn sky. It rises around 2:45 a.m., reaching its highest point at 34 degrees above the eastern horizon, before fading from sight as dawn breaks around 6:15 a.m.
Mars (magnitude -1.8) is visible in the early morning sky, rising in the east around 10:30 p.m., and achieving its highest altitude (50 degrees) above the southern horizon by about 4:20 a.m., before becoming lost in the dawn twilight by 6:15 a.m.
Jupiter and Saturn remain early evening objects, both visible side-by-side (bright Jupiter to the right) above the southeast horizon by about 8:30 p.m. Jupiter (magnitude -2.58) disappears from view around 12:40 a.m., when it sinks below seven degrees above the southeast horizon, followed by Saturn (magnitude +0.31) around 1:30 a.m., when it sinks below 10 degrees above the southwest horizon.
When the full moon closest to the Autumnal Equinox (Sept. 22), occurs in October, as it does this year on Oct. 1, it is known as the “Harvest Moon”. September’s Full Moon (Sept. 2) is referred to as the “Corn Moon,” the name given to it by Native American tribes, as this was when they usually harvested their corn crops.
Until next week, clear skies.
Events:
Sept. 2 – Full (corn) moon
Sept. 6 – Moon at apogee (farthest from Earth)
Glenn K. Roberts lives in Stratford, P.E.I., and has been an avid amateur astronomer since he was a small child. He welcomes comments from readers at glennkroberts@gmail.com.
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.
