close approach to earth

Solar System: Things to Know This Week

See history in the making on September 22! That’s the day OSIRIS-REx, the first U.S. mission to carry samples from an asteroid back to Earth, will make a close approach to Earth as it uses our planet’s gravity to slingshot itself toward the asteroid Bennu. 

Over the course of several days, observatories and amateur astronomers will be able to spot the spacecraft. Below, 10 things to know about this incredible mission that will bring us the largest sample returned from space since the Apollo era.

1. Big Deal

OSIRIS-REx seeks answers to the questions that are central to the human experience: Where did we come from? What is our destiny? Asteroids, the leftover debris from the solar system formation process, can help us answer these questions and teach us about the history of the Sun and planets.

2. That’s a Long Acronym

Yup. OSIRIS-REx stands for the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer spacecraft. The gist: It will rendezvous with, study, and return a sample of the asteroid Bennu to Earth.

3. Lots of Instruments, Too

While all the acronyms for each instrument may be alphabet soup, each has a job/role to perform in order to complete the mission. Explore what each one will do in this interactive webpage. 

4. Nice to Meet You, Bennu

Scientists chose Bennu as the mission target because of its composition, size, and proximity to Earth. Bennu is a rare B-type asteroid (primitive and carbon-rich), which is expected to have organic compounds and water-bearing minerals like clays.

5. Hard Knock Life

Bennu had a tough life in a rough neighborhood: the early solar system. It’s an asteroid the size of a small mountain born from the rubble of a violent collision, hurled through space for millions of years and dismembered by the gravity of planets—but that’s exactly what makes it a fascinating destination.

6. High Fives All Around

In 2018, OSIRIS-REx will approach Bennu and begin an intricate dance with the asteroid, mapping and studying Bennu in preparation for sample collection. In July 2020, the spacecraft will perform a daring maneuver in which its 11-foot arm will reach out for a five-second “high-five” to stir up surface material, collecting at least 2 ounces (60 grams) of small rocks and dust into a sample return capsule.

7. Home Sweet Home

OSIRIS-REx launched on September 8, 2016 from Cape Canaveral, Florida on an Atlas V rocket. In March 2021, the window for departure from the asteroid will open and OSIRIS-REx will begin its return journey to Earth, arriving two-and-a-half years later in September 2023.

8. Precious Cargo

The sample will head to Earth inside of a return capsule with a heat shield and parachutes that will separate from the spacecraft once it enters the Earth’s atmosphere. The capsule containing the sample will be collected at the Utah Test and Training Range. Once it arrives, it will be transported to NASA’s Johnson Space Center in Houston for examination. For two years after the sample return (from late 2023-2025) the science team will catalog the sample and conduct the analysis needed to meet the mission science goals. NASA will preserve at least 75% of the sample at NASA’s Johnson Space Flight Center in Houston for further research by scientists worldwide, including future generations of scientists.

9. Knowledge Is Power

Analyzing the sample will help scientists understand the early solar system, as well as the hazards and resources of near-Earth space. Asteroids are remnants of the building blocks that formed the planets and enabled life. Those like Bennu contain natural resources such as water, organics and metals. Future space exploration and economic development may rely on asteroids for these materials.

10. Hitch a Ride

Journey with OSIRIS-REx as it launches, cruises, and arrives to Bennu in this interactive timeline.

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Close Encounter with M44 : On Monday, January 26, well-tracked asteroid 2004 BL86 made its closest approach, a mere 1.2 million kilometers from our fair planet. Thats about 3.1 times the Earth-Moon distance or 4 light-seconds away. Moving quickly through Earths night sky, it left this streak in a 40 minute long exposure on January 27 made from Piemonte, Italy. The remarkably pretty telescopic field of view includes M44, also known as the Beehive or Praesepe star cluster in Cancer. Of course, its close encounter with M44 is only an apparent one, with the cluster nearly along the same line-of-sight to the near-earth asteroid. The actual distance between star cluster and asteroid is around 600 light-years. Still, the close approach to planet Earth allowed detailed radar imaging from NASAs Deep Space Network antenna at Goldstone, California and revealed the asteroid to have its own moon. via NASA

The Dream Of Your Heart

anon requested: Hi! I know you’re really busy, but could I request Newt x reader story? Uuuuff, some pretty personal stuff here 😂 She wants to create books for kids, but was often laughed at by other adults. So now she’s stuck at ‘normal’ job she hates and keeps her passion in secret. She only shows her sketches and stories to nephews/Queene’s kids. Newt finds out somehow and something fluffy happens? I really like your writing! Take all the time you need❤Just drop me a line if you’re interested😙

Authors Notes: Hi love, I really hope you like this… a couple of things… for some reason you live with Queenie with your three nephews. Don’t ask me how that happened… it just happened. Maybe she adopted you? :) Haha! Anyway, other than that…I hope you like this. I tried to include everything you requested and I was really inspired by this because I feel the same way when it comes to my writing. So, enjoy. You write those stories, love. Don’t give up!! :) It’s worth taking a chance especially with a passion!


For the millionth time (or so it seemed) you slammed your sketchbook closed as footsteps approached from behind. Your coworkers were the last people on earth with whom you would want to share your drawings. You had heard nothing but constant ridicule from them and your heart was not sure how much more it could  take. 

“Don’t you think you’re a little too old to draw that? To write about that? What is the purpose in this? Don’t you think you should focus on "real life” and not have your head in the clouds?“ 

Every time you felt a small ounce of pride in your work - there was always a critic to pull you down. 

Luckily, the ones who mattered most, always enjoyed your ideas. 

"Auntie. When do we get to read the whole thing?”

You chuckled, ruffling the hair of one of your three energetic nephews, “When I am finished writing.”

“When will it be finished?" 

You sighed, contemplating the answer. It seemed like your work would never be complete at this rate. 

"Soon, love… time for bed boys.”

“Awww..” They groaned, leaning back against a pile of feather pillows. “Will you tell us some more tomorrow?”

“Of course.”

You walked into the sitting room silently, glancing over to the table of adults. You never fit in with them. They all talked about work and bills. You however dreamed of far off places and adventures in other lands.

Would anyone ever begin to understand your heart?

You sighed sadly and turned down the hall to your bedroom just as a slender, hurried man nearly ran you over.

“So sorry.” He apologized, offering his hand towards you, “I’m Newt Scamander. You must be [your name.]

You furrowed your eyebrows. Who was this stranger coming out of your bathroom?

"Erm…I’m a friend of Queenie’s.” He tried again as your eyes examined him critically. 

Tall. Curly cinnamon hair. Sea green eyes. Blue trench coat. Strange suitcase in hand. 

You shrugged, any friend of Queenie’s was bound to be quirky. 

“Nice to meet you. Um, what are you doing here?”

“Just visiting.” His case began to rattle in his hand and you couldn’t help but nervously glance from it to his eyes repeatedly. 

“What’s…. that?” You inquired, pointing to the case as it shook.

Newt laughed nervously, shifting the suitcase to his opposite hand, “Oh…that’s nothing." 

You raised an eyebrow in suspicion, "Oh really?”

“Yes.” Newt gulped, “Nothing to concern. Have a nice day.”

Newt left through the front door in haste and you couldn’t help but shake your head. Strange man. Strange life. You were so ready for a vacation.

Several days later you found yourself sitting in Queenie’s quiet living room. You loved when the apartment was empty and you could set out your sketchbook and journal to jot down notes about your latest ideas. It was in these blissful moments you felt truly free and creative.

You closed your eyes and rested your head on the back of the sofa. Maybe a few moments of day dreaming would help you come up with your newest plot.

You were awoken a short time later by a light tapping on your shoulder. Confused, you blinked sleepily before your eyes met with two curious ones staring straight into yours.


It was Newt.

How did he get in?

"What are you doing here?"  

"I came to see Queenie. Is she in?”

“No… of course she’s not in. She’s working.” You inhaled deeply, uncertain why his presence annoyed you so much.

“Oh yes… well…” Newt rocked back on his heels and seemed to study the ceiling for a full moment before speaking again. He tapped your sketchbook with his slender finger. “I like your drawings.”

You felt your face flush.

“Oh….” You began, closing your sketchbook and journal, “Thanks. I…”

“They are very creative. Are you a writer?”

“Mmhm..” was all you could muster.

“I’m a writer too.”

This peaked your interest, “Really?”


“What do you write?”

Newt tapped his case gently, “Would you like to see?”

“See what?”

Your face must have looked mortified because Newt began to laugh.

“Well, it is easier to show you then… tell you.” Newt smirked, offering his hand.

Could you trust this man? Was he really a friend of Queenie or just some random guy who liked to break into apartments to use the bathroom?

Your insecurities seemed to melt away as something inside your heart said that you could trust him. You reached out and accepted his hand as he set his case on the floor and opened it.

“This is going to seem a bit… odd… but… do you trust me?”

You shook your head yes. What other choice did you have?

Newt smiled crookedly as he squeezed your hand. “Follow me.”

You could not believe your eyes and your heart pounded in your chest as you stepped from the real world into another dimension. You had to pinch yourself several times to see if you were still awake. Newt led you around his case with great excitement; introducing you to creatures and letting you feed them. You wondered several times if you had lost your mind.

After what felt like many hours Newt sat with you on the shed steps, drinking a cup of tea. You smiled at the sight of his white sleeves rolled up to his elbows and the tender way he stroked his… demiguise was it?… that rested on the step below you. 

You sipped from your own cup slowly, wondering when you would wake up.

“Newt, this is… extraordinary.”

“Is it?” He smirked, “Yes… I suppose it is.”

“It’s like something from a fairy tale or… a fantasy novel.”

“Like the stories you write?”

“Well… yes… sort of.”

“Well, now that I have shown you what I write about… it’s your turn.”

Newt handed you your sketchbook and journal, smiling warmly. 

You flipped through the pages slowly, trying to find the best example you could share but nothing seemed to compare to what was around you.

You sighed in frustration as you felt a warm, callused hand cover yours. “Just tell me, darling.”

Your heart felt like it would burst from such kindness. His tone was completely welcoming and sincere.

“I want to write books for children…” You opened your journal to a page covered in notes about your characters: places they lived, things they ate, how they dressed. You also began to show him some of your small sketches, “I’m only beginning." 

You peered up to gauge his reaction and he smiled brightly at your work, "It’s wonderful." 

You shut your journal quickly, "No…it’s not.”


You began to choke up, a few tears escaping down your cheeks, "I will never finish the stories I dream about.”

“Why not?" 

"My whole life I have wanted to be a writer. I want to visit libraries, read my books and share them with children all over the world. I want to make them laugh and smile. I want to convey the messages in my heart.”

Newt rubbed his hand where it rested upon yours. “Then do it.”

You scoffed, “It’s not that easy. People, adults especially, tell me I have my head stuck in the clouds. I need to live in the real world with real work and real life situations. I’m starting to wonder if they are right.”

“[your name], listen to me.” Newt cupped your chin and turned it so he could see your eyes, “Don’t let anyone tell you not to dream.”

You felt your heart fill with warmth… you weren’t sure if it was the words he spoke or the fact that you could smell his sweet mint tea breath as it fanned across your lips.

“I… I have to grow up.”

You received a hearty laugh in response, “No. No. That’s ridiculous. If YOU need to grow up then…” he motioned around the case, “what do I need to do?”

You smirked, he had a point. His world seemed completely fictional…yet, it wasn’t. You pondered that conclusion deeply for a moment and were shocked when Newt spoke nearly your own thoughts.

“My world would seem like a fantasy to someone who had never witnessed it… but here you are. Is it real?”

You shook your head yes.

“How do you know?”

“Because… it’s…” you looked around in all directions, “because it’s all around me. It feels real. It’s… I can see it.”

“Now darling, close your eyes. Can you still see my world?" 

You smiled. "Yes.”

“Right… but you can’t see it with your eyes… does that mean it’s still real?”


"Yet, what if I told you that you were still sitting on Queenie’s sofa and this was all just a story that I had made up. Would my world still be real?”

“Well… yes. In my mind." 

You continued to close your eyes as he spoke.

"Then… believe it’s real. Even if something only exists in your mind - it can still feel real. It’s a place you can go to find comfort… a safe place to find love and happiness. Does that make sense?”

You opened your eyes and smiled, tears of gratitude streamed down your face, “Yes! You’re right. It’s true.”

Newt smiled, brushing your tears away with his thumbs, “Then trust me… don’t give up on your dreams. Write the stories in your heart. Have courage and don’t worry, darling. I know you can do it.”

You caressed his cheek gently, thankful to this perfect stranger full of wisdom. 

Newt Scamander was a dream come true.

Immediately you opened your journal and sketched his face as he turned his attention back to his tea, peering out across the case undoubtedly thinking of which creature he would write about next. You smiled gently, fully aware that you had definitely found your muse.

Tag List:  @jackdawsonsgrl @fantasticnewtimagines @spn-applepie-imagines@mirkwoodshewolf@allyadarth@alina08@hiccuphaddockswife@accrosstheuniversse@withmycharacterstilltheend @johnnyssunset @allyadarth@barbarachern @demigodgirl91

anthem (3/3)

There’s a crack in everything. Olivia’s never asked Zaeed what he means by that, but she wants there to be a hopeful second half to the phrase. Eight months is a long time without Garrus.

That’s how the light gets in.

Previously on: Part 1 | Part 2

~3500 words this chapter; Olivia/Garrus, Olivia+Liara

Liara, it’s Liv. If you can hear this, please respond.

Liara mmphs in protest and turns over onto her stomach.

Liara, it’s Liv. If you can hear this, please respond.

“‘‘m asleep,” she mumbles. “Go away.” Through the haze of sleep, she wonders whether she’s properly lost her mind now - yelling at herself for talking to herself in her best friend’s voice while she’s sleeping.

Olivia’s words repeat over and over - Liara, it’s Liv. If you can hear this, please respond. Liara, it’s Liv. If you can hear this, please respond. Liara, it’s Liv. If you can hear this - and Liara gets annoyed enough that she reaches out and slaps at her nightstand, as if trying to silence a particularly-annoying alarm clock.

Ironic, she thinks as her hand connects with nothing but air, since she’s the one who once dumped a bucket of ice water over a sleeping Olivia’s head.

Please respond.

Liara blinks herself awake. Slowly, and as the message continues, she comes to the realization that this isn’t her subconscious showing its cruel side, and this isn’t Olivia in her head just messing with her. It’s an automatic message. A real message. Liara sits up in her darkened room and stares across at her terminal, and the blinking purple light.

Liara, it’s Liv. If you can hear this, please respond.

She gasps. “Olivia.” She throws the comforter off of her and nearly sprints out of bed. They must finally be within range of a working Alliance short-range comm buoy. The metal deck plating is cold against her bare feet, but she hardly notices it as she activates their comm channel.

“I’m here, Olivia,” she says through a rushed breath. No answer. “Olivia, you woke me up. The polite thing to do would be to answer the phone.”

There’s a rustle of blankets, and then a groan, followed by a clatter and a muffled “shit.” Tears spring to Liara’s eyes as she tries to tamp down a smile at her friend’s expense. She must’ve dropped her omnitool.

But it means that she’s alive. And there aren’t any hospital beeps in the background, so Olivia must also be okay.

“You woke me up,” Olivia teases in return, her voice still thick with sleep, “the least you could do is not laugh at me.”

Keep reading



In 2013 a small meteoroid, the size of a house, hurtled through Earth’s atmosphere and exploded over the Russian city of Chelyabinsk. The explosion shattered windows, and more than a thousand people were treated for injuries from flying debris. How many similar-sized rocks have orbits that bring them close to Earth? A new study has answered that question using the Dark Energy Camera (DECam) on the Blanco telescope at the Cerro Tololo Inter-American Observatory. The result lends new insights into the nature and origin of small meteoroids.

Near-Earth objects (NEOs) are asteroids or comets whose orbits bring them close to Earth’s orbit. Their close approach makes them a potential Earth-impact hazard capable of causing widespread destruction.

While very large (10-kilometer-sized) impactors can induce mass extinction events like the event that led to the demise of the dinosaurs, much smaller impactors can also wreak havoc. The meteoroid that exploded in Chelyabinsk unleashed a powerful shock wave that destroyed buildings and blew people off their feet. Relatively petite at a ‘mere’ 17 meters in diameter, comparable to the size of a 6-story building, the impactor, when it exploded, released about 10 times the energy of the Hiroshima atomic bomb.

A survey for NEOs being carried out with DECam on the 4-m Blanco telescope at the Cerro Tololo Inter-American Observatory has now estimated the number of objects in near-Earth orbit that are similar in size to the Chelyabinsk impactor. Lori Allen, Director of the Kitt Peak National Observatory and the lead investigator on the study, explained, “There are around 3.5 million NEOs larger than 10 meters, a population 10 times smaller than inferred in previous studies. About 90% of these NEOs are in the Chelyabinsk size range of 10-20 meters.”

The study, to be published in the Astronomical Journal, is the first to derive, from a single observational data set with no external model assumptions, the size distribution of NEOs from 1 kilometer down to 10 meters. A similar result was obtained in an independent study that analyzed multiple data sets (Tricarico 2017).

While the surprising results do not alter the impact threat from house-sized NEOs, which is constrained by the observed rate of Chelyabinsk-like bolide events, they do lend new insights into the nature and origin of small NEOs.

David Trilling (Northern Arizona University), the first author of the study, explained how the study reconciled the surprisingly small number of house-sized NEOs with the observed rate of Chelyabinsk-like events: “If house-sized NEOs are responsible for Chelyabinsk-like events, our results seem to say that the average impact probability of a house-sized NEO is actually 10 times greater than the average impact probability of a large NEO. That sounds strange, but it may be telling us something interesting about the dynamical history of NEOs.”

Trilling speculates that the orbital distributions of large and small NEOs differ, with small NEOs concentrated in bands of collisional debris that are more likely to impact the Earth. Bands of debris could be produced when larger NEOs fragment into swarms of smaller boulders. Testing this hypothesis is an interesting problem for the future.

Estimating the study’s detection efficiency was critical to the result. Frank Valdes (NOAO), who developed the data reduction and analysis pipeline for the project, pointed out that “the best way to measure detection efficiency is by implanting synthetic NEOs into the data stream and then detecting the fake ones in the same way real NEOs are detected.”

Well-matched to the study of small, faint NEOs, the large aperture of the 4-meter Blanco telescope and the wide field-of-view of DECam were also vital to the study. Describing the broad science reach of DECam, Allen remarked, “DECam has the power to revolutionize many fields of astronomy, from our understanding of dark matter and dark energy, to the search for distant planets in our solar system and our understanding of the near-Earth environment.”

TOP IMAGE….Orbits of known Near Earth Objects.
CENTRE IMAGE….Near Earth Objects sizes
LOWER IMAGE….Near Earth Objects family groups
BOTTOM IMAGE….Near Earth Objects populations

What’s Up for May 2016?

What’s Up for May? Two huge solar system highlights: Mercury transits the sun and Mars is closer to Earth than it has been in 11 years.

On May 9, wake up early on the west coast or step out for coffee on the east coast to see our smallest planet cross the face of the sun. The transit will also be visible from most of South America, western Africa and western Europe.

A transit occurs when one astronomical body appears to move across the face of another as seen from Earth or from a spacecraft. But be safe! You’ll need to view the sun and Mercury through a solar filter when looking through a telescope or when projecting the image of the solar disk onto a safe surface. Look a little south of the sun’s Equator. It will take about 7 ½ hours for the tiny planet’s disk to cross the sun completely. Since Mercury is so tiny it will appear as a very small round speck, whether it’s seen through a telescope or projected through a solar filter. The next Mercury transit will be Nov. 11, 2019.

Two other May highlights involve Mars. On May 22 Mars opposition occurs. That’s when Mars, Earth and the sun all line up, with Earth directly in the middle.

Eight days later on May 30, Mars and Earth are nearest to each other in their orbits around the sun. Mars is over half a million miles closer to Earth at closest approach than at opposition. But you won’t see much change in the diameter and brightness between these two dates. As Mars comes closer to Earth in its orbit, it appears larger and larger and brighter and brighter. 

During this time Mars rises after the sun sets. The best time to see Mars at its brightest is when it is highest in the sky, around midnight in May and a little earlier in June. 

Through a telescope you can make out some of the dark features on the planet, some of the lighter features and sometimes polar ice and dust storm-obscured areas showing very little detail.

After close approach, Earth sweeps past Mars quickly. So the planet appears large and bright for only a couple weeks. 

But don’t worry if you miss 2016’s close approach. 2018’s will be even better, as Mars’ close approach will be, well, even closer.

You can find out about our #JourneytoMars missions at, and you can learn about all of our missions at

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Asteroid to Pass Near Earth on Halloween

This Halloween, the Earth will have a visitor nearly on its doorstep. But it won’t be looking for candy or tossing an egg at our windows—it’s asteroid 2015 TB145, and its flyby, while close, is no reason to be scared.

The visitor was discovered earlier this month with the help of the University of Hawaii’s Pan-STARRS-1 telescope, part of NASA’s Near-Earth Object (NEO) Program, and is an unexpected boon to asteroid researchers.

“Every close-up view of an asteroid tells us more about their structure and composition, information we will need to someday deflect a real threat”, says Department of Earth and Planetary Sciences Curator Denton Ebel.

Since TB145 will be passing the Earth just a little farther than the orbit of the Moon—almost close enough to shout “trick or treat!”—researchers are aiming to learn everything they can about the 400-foot-wide object while the chance presents itself. It likely won’t be visible to the naked eye, but NASA is preparing to get high-resolution looks at the object as it nears Earth using radar and optical imaging.

“The close approach of 2015 TB145 at about 1.3 times the distance of the Moon’s orbit, coupled with its size, suggests it will be one of the best asteroids for radar imaging we’ll see for several years,” Lance Brenner, the head of NASA’s asteroid research program, said in a statement. The unexpected viewing is a great chance to learn more about asteroids, as the next appearance of an object of comparable size so close to Earth is not anticipated until 2027.

Until then, the Museum offers plenty of other ways to learn about asteroids, including a new series of video explainers featuringDr. Ebel. You can view the latest, which details the largest asteroids to ever hit the Earth, below:

Learn more about near-earth asteroids. 

Hubble takes Mars portrait near close approach

Bright, frosty polar caps, and clouds above a vivid, rust-colored landscape reveal Mars as a dynamic seasonal planet in this NASA Hubble Space Telescope view taken on May 12, 2016, when Mars was 50 million miles from Earth. The Hubble image reveals details as small as 20 to 30 miles across.

The large, dark region at far right is Syrtis Major Planitia, one of the first features identified on the surface of the planet by seventeenth-century observers. Christiaan Huygens used this feature to measure the rotation rate of Mars. (A Martian day is about 24 hours and 37 minutes.) Today we know that Syrtis Major is an ancient, inactive shield volcano. Late-afternoon clouds surround its summit in this view.

A large oval feature to the south of Syrtis Major is the bright Hellas Planitia basin. About 1,100 miles across and nearly five miles deep, it was formed about 3.5 billion years ago by an asteroid impact.

The orange area in the center of the image is Arabia Terra, a vast upland region in northern Mars that covers about 2,800 miles. The landscape is densely cratered and heavily eroded, indicating that it could be among the oldest terrains on the planet. Dried river canyons (too small to be seen here) wind through the region and empty into the large northern lowlands.

South of Arabia Terra, running east to west along the equator, are the long dark features known as Sinus Sabaeus (to the east) and Sinus Meridiani (to the west). These darker regions are covered by dark bedrock and fine-grained sand deposits ground down from ancient lava flows and other volcanic features. These sand grains are coarser and less reflective than the fine dust that gives the brighter regions of Mars their ruddy appearance. Early Mars watchers first mapped these regions.

An extended blanket of clouds can be seen over the southern polar cap. The icy northern polar cap has receded to a comparatively small size because it is now late summer in the northern hemisphere. Hubble photographed a wispy afternoon lateral cloud extending for at least 1,000 miles at mid-northern latitudes. Early morning clouds and haze extend along the western limb.

This hemisphere of Mars contains landing sites for several NASA Mars surface robotic missions, including Viking 1 (1976), Mars Pathfinder (1997), and the still-operating Opportunity Mars rover. The landing sites of the Spirit and Curiosity Mars rovers are on the other side of the planet.

This observation was made just a few days before Mars opposition on May 22, when the sun and Mars will be on exact opposite sides of Earth, and when Mars will be at a distance of 47.4 million miles from Earth. On May 30, Mars will be the closest it has been to Earth in 11 years, at a distance of 46.8 million miles. Mars is especially photogenic during opposition because it can be seen fully illuminated by the sun as viewed from Earth.

The biennial close approaches between Mars and Earth are not all the same. Mars’ orbit around the sun is markedly elliptical; the close approaches to Earth can range from 35 million to 63 million miles.

They occur because about every two years Earth’s orbit catches up to Mars’ orbit, aligning the sun, Earth, and Mars in a straight line, so that Mars and the sun are on “opposing” sides of Earth. This phenomenon is a result of the difference in orbital periods between Earth’s orbit and Mars’ orbit. While Earth takes the familiar 365 days to travel once around the sun, Mars takes 687 Earth days to make its trip around our star. As a result, Earth makes almost two full orbits in the time it takes Mars to make just one, resulting in the occurrence of Martian oppositions about every 26 months.