Orca🐋 The killer whale🐳🐋

 The orca (Orcinus orca), or killer whale, is a toothed whale that is the largest member of the oceanic dolphin family. It is the only extant species in the genus Orcinus. Orcas are recognizable by their black-and-white patterned body. A cosmopolitan species, orcas are found in diverse marine environments, from Arctic to Antarctic regions to tropical seas.

Scientific classificationEdit this classification

Domain: Eukaryota

Kingdom: Animalia

Phylum: Chordata

Class: Mammalia

Order: Artiodactyla

Infraorder: Cetacea

Family: Delphinidae

Genus: Orcinus

Species: O. orca

Synonyms

Delphinus orca Linnaeus, 1758

Delphinus gladiator Bonnaterre, 1789

Orca gladiator (Bonnaterre, 1789)

Orcas are apex predators with a diverse diet. Individual populations often specialize in particular types of prey. This includes a variety of fish, sharks, rays, and marine mammals such as seals and other dolphins and whales. They are highly social; some populations are composed of highly stable matrilineal family groups (pods). Their sophisticated hunting techniques and vocal behaviors, often specific to a particular group and passed along from generation to generation are considered to be manifestations of animal culture.

The International Union for Conservation of Nature assesses the orca's conservation status as data deficient because of the likelihood that two or more orca types are separate species. Some local populations are considered threatened or endangered due to prey depletion, habitat loss, pollution (by PCBs), capture for marine mammal parks, and conflicts with human fisheries. In late 2005, the southern resident orcas, which swim in British Columbia and Washington waters, were placed on the U.S. Endangered Species list.

Orcas are not usually a threat to humans, and no fatal attack has ever been documented in their natural habitat. There have been cases of captive orcas killing or injuring their handlers at marine theme parks. Orcas feature strongly in the mythologies of indigenous cultures, and their reputation in different cultures ranges from being the souls of humans to merciless killers.

The Blue Whale🐳🐋

 The blue whale (Balaenoptera musculus) is a marine mammal and a baleen whale. Reaching a maximum confirmed length of 29.9 meters (98 ft) and weighing up to 199 tonnes (196 long tons; 219 short tons), it is the largest animal known ever to have existed.[a] The blue whale's long and slender body can be of various shades of greyish-blue dorsally and somewhat lighter underneath. Four subspecies are recognized: B. m. musculus in the North Atlantic and North Pacific, B. m. intermedia in the Southern Ocean, B. m. brevicauda (the pygmy blue whale) in the Indian Ocean and South Pacific Ocean, and B. m. indica in the Northern Indian Ocean. There is also a population in the waters off Chile that may constitute a fifth subspecies.

Domain: Eukaryota

Kingdom: Animalia

Phylum: Chordata

Class: Mammalia

Order: Artiodactyla

Infraorder: Cetacea

Family: Balaenopteridae

Genus: Balaenoptera

Species: B. musculus

Binomial name

Balaenoptera musculus

(Linnaeus, 1758)

Subspecies

B. m. brevicauda Ichihara, 1966

?B. m. indica Blyth, 1859

B. m. intermedia Burmeister, 1871

B. m. musculus Linnaeus, 1758

Synonyms

Balaena musculus Linnaeus, 1758

Balaenoptera gibbar Scoresby, 1820

Pterobalaena gigas Van Beneden, 1861

Physalus latirostris Flower, 1864

Sibbaldius borealis Gray, 1866

Flowerius gigas Lilljeborg, 1867

Sibbaldius sulfureus Cope, 1869

Balaenoptera sibbaldii Sars, 1875In general, blue whale populations migrate between their summer feeding areas near the poles and their winter breeding grounds near the tropics. There is also evidence of year-round residencies, and partial or age/sex-based migration. Blue whales are filter feeders; their diet consists almost exclusively of krill. They are generally solitary or gather in small groups, and have no well-defined social structure other than mother–calf bonds. The fundamental frequency for blue whale vocalizations ranges from 8 to 25 Hz and the production of vocalizations may vary by region, season, behavior, and time of day. Orcas are their only natural predators.

The blue whale was once abundant in nearly all the Earth's oceans until the end of the 19th century. It was hunted almost to the point of extinction by whalers until the International Whaling Commission banned all blue whale hunting in 1966. The International Union for Conservation of Nature has listed blue whales as Endangered as of 2018. It continues to face numerous man-made threats such as ship strikes, pollution, ocean noise, and climate change.

হুম গুটি খেলা

 ১ মণ ওজনের পিতলের তৈরি গুটি করায়াত্ত করে নিজ গ্রামে নিয়ে গুম করা পর্যন্ত চলে এই খেলা। শুরুতে উত্তর, দক্ষিণ, পূর্ব ও পশ্চিম ভাগবাটোয়ারা করে খেলা শুরু হলেও পরে আর কোন দিক থাকেনা। একেক এলাকার একেকটি নিশানা থাকে এবং ঐ নিশানা দেখে বুঝা যায় কারা কার পক্ষের লোক। গুটিটি কোন দিকে যাচ্ছে তা চিহিৃত করা হয় নিশানা দেখেই।হুমগুটি হল ময়মনসিংহের ফুলবাড়িয়া উপজেলায় লক্ষ্মীপুরের বড়ই আটায় তালুক-পরগনার সীমানায় অনুষ্ঠিত একটি ঐতিহ্যবাহী খেলা। ব্রিটিশ আমলে জমিদারদের জমি পরিমাপের বিরোধের মীমাংসা করতে আয়োজন হয়েছিল এই খেলার। পরবর্তীতে আমন ধান কাটা শেষ, বোরো ধান আবাদের আগে প্রজাদের শক্তি পরীক্ষার জন্য জমিদারদের এই পাতানো খেলা চলছে আড়াইশো বছরেরও অধিক সময় ধরে।

বৈশিষ্ট্যসমূহ

ধরন - দলগত খেলা

খেলার সরঞ্জাম - হুমগুটি

ভেন্যু - বড়ই আটাবন্ধ মাঠ, ফুলবাড়িয়া, ময়মনসিংহ

প্রচলন - দেশ বা অঞ্চল

ইতিহাস ঃঃ

ফুলবাড়িয়া,ময়মনসিংহ,বাংলাদেশ২৫০ বছর আগে মুক্তাগাছার রাজা শশীকান্ত আচার্য্যের সঙ্গে ত্রিশালের বৈলরের জমিদার হেমচন্দ্র রায়ের জমির পরিমাপ নিয়ে বিরোধের সৃষ্টি হয়। তখনকার দিনে তালুকের প্রতি কাঠা জমির পরিমাপ ছিল ১০ শতাংশে, পরগনার প্রতি কাঠা জমির পরিমাপ ছিল সাড়ে ৬ শতাংশে। একই জমিদারের জমিতে দুই নীতির কারণে প্রতিবাদী আন্দোলন শুরু হয়। এই বিরোধ মীমাংসা করার জন্য লক্ষ্ণীপুর গ্রামের বড়ই আটা নামক স্থানে ‘তালুক-পরগনার সীমানায়’ এই গুটি খেলার আয়োজন শুরু করা হয়। গুটি খেলার শর্ত ছিল গুটি গুমকারী এলাকাকে ‘তালুক’ এবং পরাজিত অংশের নাম হবে ‘পরগনা’। মুক্তাগাছা জমিদারের প্রজারা বিজয়ী হয় জমিদার আমলের সেই গুটি খেলায়।

স্থানীয় মোড়ল পরিবার বর্তমানে ধারাবাহিকভাবে এই খেলার আয়োজন করে আসছে। 

ঢাকা গেইট/ মীর জুমলার গেইট।

 মীর জুমলার গেট ঢাকা বিশ্ববিদ্যালয় এলাকার একটি ঐতিহাসিক মোগল স্থাপনা। এই গেটটি ঢাকা গেট, ময়মনসিংহ গেট নামেও পরিচিত। বিশ্ববিদ্যালয় এলাকার কার্জন হল ছাড়িয়ে দোয়েল চত্বর হয়ে বাংলা একাডেমী যেতে চোখে পড়ে হলুদ রঙের মীর জুমলার তোরণ। এ গেটের তিনটি অংশের একটি রয়েছে বিশ্ববিদ্যালয়ের নবায়নযোগ্য শক্তি গবেষণা কেন্দ্রের দিকে, মাঝখানের অংশ পড়েছে রোড ডিভাইডারের মাঝে এবং অপর অংশটি রয়েছে সোহরাওয়ার্দী উদ্যানের দিকে তিন নেতার মাজারের পাশে।

                   সাধারণ তথ্য

স্থাপত্য রীতি

মুঘল স্থাপত্য

অবস্থান

ঢাকা, বাংলাদেশ

নির্মাণকাজের সমাপ্তি

১৭শ শতাব্দী

স্থপতি

মীর জুমলা

নকশা এবং নির্মাণ

মীর জুমলাব্রিটিশ সময়কার ঢাকার ম্যাজিস্ট্রেট চার্লস ডয়'স মূল শহরের সঙ্গে রেসকোর্সকে সংযুক্ত করার জন্য ময়দানের উত্তর-পূর্ব দিকে একটি সড়ক তৈরি করেন। এই সড়কের প্রবেশপথে তৈরি করা হয় দুটি স্তম্ভ। অপর এক তথ্যে বলা হয়েছে, ইসলাম খাঁর আমলে রমনা অঞ্চলে ছিল বাগে বাদশাহী নামে মোগল উদ্যান। বাগে বাদশাহীর প্রবেশপথে ছিল দুটি স্তম্ভ। পরে তা পুনর্নির্মাণ করে নামকরণ করা হয় ময়মনসিংহ গেট।

নাম করন ও অবস্থান ঃ

মোগল আমলে বুড়িগঙ্গা নদী হয়ে ঢাকায় প্রবেশ করতে ব্যবহার করা হতো এ তোরণ। সেই সময় এর নাম ছিল 'মীর জুমলার গেট'। পরে কখনও 'ময়মনসিংহ গেট', কখনও 'ঢাকা গেট' এবং অনেক পরে নামকরণ করা হয় 'রমনা গেট'। এ গেট রমনায় প্রবেশ করার জন্য ব্যবহার করা হতো বলে পরে সাধারণ মানুষের কাছে এটি রমনা গেট নামেই পরিচিতি পায়। তবে বাংলাদেশ সরকারের গেজেট অনুসারে এ তোরণ এবং আশপাশের জায়গার নাম দেওয়া হয়েছে 'মীর জুমলার গেট'।তোরণের স্তম্ভগুলো পরীক্ষা করেন এ. এইচ. দানী। তার মতে, এগুলো মোগল আমলে তৈরি হয়নি। কারণ স্তম্ভ দুটির গড়ন ইউরোপীয় ধাঁচে মূল শহরের সঙ্গে রেসকোর্সকে যুক্ত করার জন্য রেসকোর্সের উত্তর-পূর্ব দিকে একটি রাস্তা তৈরি করেন তৎকালীন ম্যাজিস্ট্রেট চার্লস ডস। এ রাস্তার প্রবেশমুখে ডস এ দুটি স্তম্ভ তৈরি করেন। যা এখনও অটুট রয়েছে। বর্তমান নজরুল এভিনিউর রাস্তাটিও ডস তৈরি করেন। 'বাগে বাদশাহী' নামে মোগল উদ্যানটি ইসলাম খাঁর আমলে ছিল রমনা অঞ্চলে (যেটি বর্তমান সোহরাওয়ার্দী উদ্যান ও পুরনো হাইকোর্ট ভবন)। হাইকোর্ট ভবনের পূর্ব কোণে একই ধরনের দুটি স্তম্ভবিশিষ্ট প্রবেশপথ ছিল। মূলত সে সময় এ স্তম্ভের মধ্য দিয়ে চলাচল ছিল হাতির। ২০২৩ সালের ডিসেম্বরে ওসমানী উদ্যান থেকে মীর জুমলার কামানটি সরিয়ে মীর জুমলা গেটের সামনে স্থাপন করা হয়।

তথ্যঃ

প্রায় ১০০ থেকে ১৫০ ইঞ্চি ব্যাসার্ধ এ ধরনের স্তম্ভ খুবই বিরল। যার ওপরে রয়েছে কারুকাজ করা চারকোনা বিশিষ্ট একটি শেড। পশ্চিম পাশের বড় স্তম্ভের পাশেই রয়েছে অপেক্ষাকৃত ছোট আরেকটি স্তম্ভ। যার মাঝে টানা অবস্থায় রয়েছে একটি দেয়াল। উঁচু থেকে নিচুতে নামা এ দেয়ালটি প্রায় ২০ ইঞ্চি চওড়া। কিন্তু পূর্ব পাশের বড় স্তম্ভের সঙ্গে দেয়াল বা প্রাচীর থাকলেও নেই ছোট স্তম্ভ।

মঙ্গল গ্রহ(Mars🪐)

 

মঙ্গল হলো সূর্য থেকে চতুর্থ দূরবর্তী গ্রহ এবং বুধের পরেই সৌরজগতের দ্বিতীয়-ক্ষুদ্রতম গ্রহ। ইংরেজি ভাষায় মঙ্গল গ্রহ রোমান পুরাণের যুদ্ধদেবতা মার্সের নাম বহন করে এবং প্রায়শই এই গ্রহটিকে “লাল গ্রহ” নামে অভিহিত করা হয়।এর জন্য দায়ী এই গ্রহের পৃষ্ঠতলে ফেরিক অক্সাইডের আধিক্য, যার ফলে গ্রহটিকে লালচে রঙের দেখায় এবং খালি চোখে দৃশ্যমান মহাজাগতিক বস্তুগুলির মধ্যে এই গ্রহটিকে স্বতন্ত্রভাবে দর্শনীয় করে তোলে।মঙ্গল একটি শিলাময় গ্রহ এবং এর বায়ুমণ্ডল ঘনত্বহীন। এই গ্রহের পৃষ্ঠভাগের বৈশিষ্ট্যগুলির মধ্যে যেমন চাঁদের মতো অভিঘাত খাদ দেখা যায়, তেমনি পৃথিবীর মতো উপত্যকা, মরুভূমি ও মেরুস্থ হিমছত্রও চোখে পড়ে।

বিবরণউচ্চারণমোংগোল্ গ্রোহো বিশেষণমঙ্গলীয়কক্ষপথের বৈশিষ্ট্য যুগ জে২০০০অপসূর২৪৯২০০০০০ কিমি

(১৫৪৮০০০০০ মা; ১.৬৬৬ AU)অনুসূর২০৬৭০০০০০ কিমি

(১২৮৪০০০০০ মা; ১.৩৮২ AU)অর্ধ-মুখ্য অক্ষ২২৭৯৩৯২০০ কিমি

(১৪১৬৩৪৯০০ মা; ১.৫২৩৬৭৯ AU)উৎকেন্দ্রিকতা০.০৯৩৪কক্ষীয় পর্যায়কাল৬৮৬.৯৮০ d

(১.৮৮০৮৫ yr; ৬৬৮.৫৯৯১ সোলস)[২]যুতিকাল৭৭৯.৯৬ d

(২.১৩৫৪ yr)গড় কক্ষীয় দ্রুতি২৪.০০৭ km/s

(৮৬৪৩০ কিমি/ঘ; ৫৩৭০০ মা/ঘ)গড় ব্যত্যয়১৯.৪১২° নতি

১.৮৫০° গ্রহণরেখার দিকে;

৫.৬৫° সূর্যের বিষুবরেখার দিকে;

১.৬৩° অপরিবর্তনীয় সমতলের দিকে

উদ্বিন্দুর দ্রাঘিমা৪৯.৫৫৮°নিকটবিন্দুর সময়৩ আগস্ট ২০২০ অনুসূরের উপপত্তি২৮৬.৫০২°উপগ্রহসমূহ২ভৌত বৈশিষ্ট্যসমূহগড় ব্যাসার্ধ৩৩৮৯.৫ ± ০.২ কিমি

(২১০৬.১ ± ০.১ মা)বিষুবীয় ব্যাসার্ধ৩৩৯৬.২ ± ০.১ কিমি

(২১১০.৩ ± ০.১ মা; 0.533 Earths)মেরু ব্যাসার্ধ৩৩৭৬.২ ± ০.১ কিমি

(২০৯৭.৯ ± ০.১ মা; 0.531 Earths)সমরূপতার০.০০৫৮৯±০.০০০১৫পৃষ্ঠের ক্ষেত্রফল১৪৪৭৯৮৫০০ কিমি২

(৫৫৯০৭০০০ মা২; 0.284 Earths)আয়তন১.৬৩১৮×১০১১ km3

(0.151 Earths)ভর৬.৪১৭১×১০২৩ কিg

(0.107 Earths)গড় ঘনত্ব৩.৯৩৩৫ গ্রাম/সেমি৩

(০.১৪২১ পা/ইঞ্চি৩)বিষুবীয় পৃষ্ঠের অভিকর্ষ৩.৭২০৭৬ মি/সে২

(১২.২০৭২ ফুট/সে২; 0.3794 g)মুক্তি বেগ৫.০২৭ km/s

(১৮১০০ কিমি/ঘ; ১১২৫০ মা/ঘ)ঘূর্ণনকাল১.০২৮ d

 ২৪ঘ ৩৯মি ৩৬সে (synodic; solar day)নাক্ষত্রিক ঘূর্ণনকাল১.০২৫৯৫৭ d

 ২৪ঘ ৩৭মি ২২.৭সে.বিষুবীয় অঞ্চলে ঘূর্ণন বেগ২৪১.১৭ মি/সে

(৮৬৮.২২ কিমি/ঘ; ৫৩৯.৪৯ মা/ঘ)অক্ষীয় ঢাল২৫.১৯° (কক্ষতলের প্রতি)উত্তর মেরুর বিষুবাংশ৩১৭.৬৮১৪৩°

 ২১ঘ ১০মি ৪৪সেউত্তর মেরুর বিষুবলম্ব৫২.৮৮৬৫০°প্রতিফলন অনুপাত

0.170 geometric

0.25 Bond

পৃষ্ঠের তাপমাত্রান্যূনমধ্যকসর্বোচ্চকেলভিন১৩০ কে২১০ কে ৩০৮ কেসেলসিয়াস−১৪৩ °সি−৬৩ °সি৩৫ °Cআপাত মান−২.৯৪ থেকে +১.৮৬কৌণিক ব্যাস৩.৫–২৫.১″বায়ুমণ্ডল পৃষ্ঠের চাপ০.৬৩৬ (০.৪–০.৮৭) কেপা

০.০০৬২৮ atmগঠন

• ৯৫.৯৭% কার্বন ডাই অক্সাইড

• ১.৯৩% আর্গন

• ১.৮৯% নাইট্রোজেন

• ০.১৪৬% অক্সিজেন

• ০.০৫৫৭% কার্বন মনোক্সাইড

• ০.০২১০% জলীয় বাষ্প

• ০.০১০০% নাইট্রোজেন অক্সাইড

• ০.০০০২৫% নিয়ন

• ০.০০০০৮% হাইড্রোজেন ডিউটেরিয়াম অক্সাইড

• ০.০০০০৩% ক্রিপ্টন

• ০.০০০০১% জেনন

Ronda Jean Rousey🥊🥊(WWE)

 Ronda Jean Rousey (/ˈraʊzi/born February 1, 1987) is an American professional wrestler, actress, and former judoka and mixed martial artist.She is known for her time in Ultimate Fighting Championship (UFC) and WWE.

She was the first American woman to win an Olympic medal in judo by winning bronze at the 2008 Summer Olympics. Rousey began her mixed martial arts (MMA) career with King of the Cage in 2011. She soon joined Strikeforce, becoming their last Women's Bantamweight Champion until its acquisition by UFC. Rousey was part of the company's first-ever female fight at UFC 157, was their inaugural Women's Bantamweight Champion, and held the record for most UFC title defenses (6) by a female, until being surpassed by Valentina Shevchenko in 2022. Rousey retired from MMA in 2016 and was the first female fighter inducted into the UFC Hall of Fame in 2018.

Rousey began a career in professional wrestling in 2018, signing with WWE, and debuted at WrestleMania 34. She won the Raw Women's Championship at that year's SummerSlam, and headlined WWE's only all-women's pay-per-view Evolution, in which she defended the title. Rousey lost the title in the first-ever women's WrestleMania main event at WrestleMania 35. Rousey returned at the 2022 Royal Rumble, winning the women's Royal Rumble match. That year, she would win the SmackDown Women's Championship twice, making her an overall three-time women's world champion in WWE. She became the eighth Women's Triple Crown Champion when she won the WWE Women's Tag Team Championship with Shayna Baszler. Rousey and Baszler also unified the WWE and NXT Women's Tag Team Championships. After leaving WWE in October 2023, she began wrestling on the independent circuit.

Rousey is the only woman to be the champion in both the UFC and WWE as well as the only woman to headline a pay-per-view event in both companies.She was voted the best female athlete of all time in a 2015 ESPN fan poll, and Fox Sports described her as "one of the defining athletes of the 21st century."Rousey has also appeared in films, including The Expendables 3 (2014), Furious 7 (2015), and Mile 22 (2018),and published her autobiography My Fight / Your Fight in 2015.,

🥊🥊🥊🥊🥊🎗️🎗️🎗️🎗️

Women's judo

Representing United States

Olympic Games

Bronze medal – third place 2008 Beijing ‍–‍70 kg

World Championships

Silver medal – second place 2007 Rio de Janeiro ‍–‍70 kg

Pan American Games

Gold medal – first place 2007 Rio de Janeiro ‍–‍70 kg

Pan American Championships

Gold medal – first place 2004 Isla Margarita ‍–‍63 kg

Gold medal – first place 2005 Caguas ‍–‍63 kg

Silver medal – second place 2006 Buenos Aires ‍–‍63 kg

Bronze medal – third place 2007 Montreal ‍–‍70 kg

World Juniors Championships

Gold medal – first place 2004 Budapest ‍–‍63 kg

Bronze medal – third place 2006 Santo Domingo ‍–‍63 kg

Professional wrestling carrier 

Ring name(s)

Ronda Rousey

Billed height

5 ft 7 in (170 cm)

Billed weight

134 lb (61 kg)

Trained by

Brian Kendrick

Goldust

Kurt Angle

Natalya

WWE Performance Center

Debut

April 8, 2018

#fvrtone🎗️

#womenchampion🥊🎗️

The Moon🌙🌕

 The Moon is Earth's only natural satellite. It orbits at an average distance of 384,400 km (238,900 mi), about 30 times Earth's diameter. The Moon always presents the same side to Earth, because gravitational pull has locked its rotation to the planet. This results in the lunar day of 29.5 Earth days matching the lunar month. The Moon's gravitational pull – and to a lesser extent the Sun's – are the main drivers of the tides.

 

                 Designation

Earth I

Alternative names

LunaSelene (poetic)Cynthia (poetic)

Adjectives

LunarSelenian (poetic)Cynthian (poetic)Moonly (poetic)

  symbol: 

☾ or ☽

Orbital characteristics

Epoch J2000

Perigee

362600 km

(356400–370400 km)

Apogee

405400 km

(404000–406700 km)

Semi-major axis

384399 km  (1.28 ls, 0.00257 AU)

Eccentricity

0.0549

Orbital period (sidereal)

27.321661 d

(27 d 7 h 43 min 11.5 s)

Orbital period (synodic)

29.530589 d

(29 d 12 h 44 min 2.9 s)

Average orbital speed

1.022 km/s

Inclination

5.145° to the ecliptic.

🌙🌙🌙🌙🌙🌙🌙🌙🌙

      🌕🌕🌕🌕🌕🌕🌕🌕🌕🌕🌕

Longitude of ascending node

Regressing by one revolution in 18.61 years

Argument of perigee

Progressing by one

revolution in 8.85 years

Satellite of

Earth

Physical characteristics:

Mean radius

1737.4 km  

(0.2727 of Earth's)

Equatorial radius

1738.1 km  

(0.2725 of Earth's)

Polar radius

1736.0 km  

(0.2731 of Earth's)

Flattening

0.0012

Circumference

10921 km  (equatorial)

Surface area

3.793×107 km2  

(0.074 of Earth's)

Volume

2.1958×1010 km3  

(0.02 of Earth's)

Mass

7.342×1022 kg  

(0.0123 of Earth's)

Mean density

3.344 g/cm3

0.606 × Earth

Surface gravity

1.622 m/s2  {(0.1654 g; 5.318 ft/s2)

Moment of inertia factor

0.3929±0.0009

Escape velocity

2.38 km/s

(8600 km/h; 5300 mph)

Synodic rotation period

29.530589 d

(29 d 12 h 44 min 2.9 s; synodic; solar day) (spin-orbit locked)

Sidereal rotation period

27.321661 d  (spin-orbit locked)

Equatorial rotation velocity

4.627 m/s

Axial tilt

1.5424° to ecliptic

6.687° to orbit plane

24° to Earth's equator 

North pole right ascension

17h 47m 26s

266.86°

North pole declination

65.64°

Albedo

0.136

Surface temp.

min mean max

Equator 100 K 2

50 K 390 K

85°N 150 K 230 K

Surface absorbed dose rate

13.2 μGy/h

(during lunar daytime)

Surface equivalent dose rate

57.0 μSv/h

(during lunar daytime)

Apparent magnitude

−2.5 to −12.9[c]

−12.74  (mean full moon)

Absolute magnitude 

0.2

Angular diameter

29.3 to 34.1 arcminutes

Atmosphere[16]

Surface pressure

10−7 Pa (1 picobar)  (day)

10−10 Pa (1 femtobar)   

(night)[e]

By Akhey🗺️

#moon🌕

Planets,🪐🌌

 Our solar system has eight planets, and five dwarf planets - all located in an outer spiral arm of the Milky Way galaxy called the Orion Arm, or Orion Spur.

It can be divided into three regions: the inner solar system, the outer solar system, the Kuiper Belt, and the Oort Cloud.

The inner, rocky planets are Mercury, Venus, Earth, and Mars. These worlds also are known as terrestrial planets because they have solid surfaces. Mercury, Earth, and Mars are currently being explored by spacecraft. Two rovers are on the surface of Mars. NASA's newest rover — Perseverance — landed on Mars on Feb. 18, 2021. Three missions are in development to return to Venus.

The outer planets are gas giants Jupiter and Saturn, and ice giants Uranus and Neptune. NASA's Juno spacecraft is on an extended mission at Jupiter, and ESA's JUICE mission is on the way. NASA also is building Europa Clipper and Dragonfly to explore moons of Jupiter and Saturn.

Beyond Neptune, a newer class of smaller worlds called dwarf planets reign, including longtime favorite Pluto. NASA's New Horizons spacecraft visited Pluto in 2015, and is currently exploring the Kuiper Belt beyond Pluto.

The other dwarf planets are Ceres, Makemake, Haumea, and Eris.

Thousands more planets have been discovered beyond our solar system. Scientists call them exoplanets (exo means "from outside"). 

#planets

#entatinment

#earth

List about the nearest stars in the Universe 🪐🌌🌠

 This list covers all known stars, brown dwarfs, and sub-brown dwarfs within 20 light-years (6.13 parsecs) of the Sun. So far, 131 such objects have been found. Only 22 are bright enough to be visible without a telescope, for which the star's visible light needs to reach or exceed the dimmest brightness visible to the naked eye from Earth, 6.5 apparent magnitude.

Animated 3D map of the nearest stars, centered on the Sun.  3D red green glasses are recommended to view this image correctly.

A radar map of the positions and distances of all known sufficiently separate stellar objects within 9 light years (ly). Positions are marked (◆) around Sol according to their right ascension (clockwise in hours angle) and inward according to their declination, entered as lines (doted when negative) of their top-down viewed arcs between each's position and distance mark (▬). The marked distances are measured outward from the center with each ly represented by a concentric circle. For within 12 ly see this map.

The known 131 objects are bound in 94 stellar systems. Of those, 103 are main sequence stars: 80 red dwarfs and 23 "typical" stars having greater mass. Additionally, astronomers have found 6 white dwarfs (stars that have exhausted all fusible hydrogen), 21 brown dwarfs, as well as 1 sub-brown dwarf, WISE 0855−0714 (possibly a rogue planet). The closest system is Alpha Centauri, with Proxima Centauri as the closest star in that system, at 4.2465 light-years from Earth. The brightest, most massive and most luminous object among those 131 is Sirius A, which is also the brightest star in Earth's night sky; its white dwarf companion Sirius B is the hottest object among them. The largest object within the 20 light-years is Procyon.

The Solar System, and the other stars/dwarfs listed here, are currently moving within (or near) the Local Interstellar Cloud, roughly 30 light-years (9.2 pc) across. The Local Interstellar Cloud is, in turn, contained inside the Local Bubble, a cavity in the interstellar medium about 300 light-years (92.0 pc) across. It contains Ursa Major and the Hyades star cluster, among others. The Local Bubble also contains the neighboring G-Cloud, which contains the stars Alpha Centauri and Altair. In the galactic context, the Local Bubble is a small part of the Orion Arm, which contains most stars that we can see without a telescope. The Orion arm is one of the spiral arms of our Milky Way galaxy. 

#galaxy

#universe

The nearest star⭐(proxima Centauri)

 Proxima Centauri is the dimmest and smallest of the Alpha Centauri system, but it has the honor of being the nearest star.

PROXIMA CENTAURI VITALS

Official name (IAU-approved) Proxima Centauri

Other Designations Alpha Centauri C, HIP 70890

Nicknames --

Apparent Magnitude 11.13

Distance from Earth 4.24 light-years

Type :M5.5

Color :Red

Mass :0.123 M☉

Radius :0.15 R☉

Constellation Centaurus

Right Ascension 14h 29m 43s

Declination -62° 40' 46”

Multiple system? Yes, third member of the Alpha Centauri system

Variable star? Yes, eruptive variable

Exoplanets status Two known exoplanets

Probable fate White dwarf

PHYSICAL CHARACTERISTICS:

Of all the stars in the universe — and there are untold billions of them — Proxima Centauri, a run-of-the-mill red dwarf star, is closest to the Sun. It’s about 14% the Sun’s diameter and located in the southern celestial sky.This graphic shows the relative sizes of several stars and Jupiter, including the three known members of the Alpha Centauri triple system. (The Sun is between Rigil Kentaurus and Toliman.)

ESO

But wait, you may be thinking, I thought Alpha Centauri was the closest star to the Sun. Well, that’s basically true, too. Even casual space enthusiasts are familiar with the name Alpha Centauri. Located a “mere” 4.35 light-years away, it’s indeed the closest of the Sun’s stellar neighbors, but this isn’t the whole story. Although Alpha Centauri appears to be a singleton to the unaided eye, closer inspection shows that it’s actually a system of three stars. Two of them, Alpha Centauri A and Bofficially named Rigil Kentaurus and Toliman, respectively), are a binary pair that are roughly the same size as the Sun. We see the combined light of these two stars when we’re looking at Alpha Centauri.But the third member of the group, separated from the other two by a considerable distance, is Alpha Centauri C — or as it’s officially known, Proxima Centauri. Proxima is about 4.24 light-years from our neighborhood, so it’s this stellar runt that currently holds the precise distinction of “closest.” Despite its proximity, Proxima is quite dim, partly because it outputs much of its energy at infrared wavelengths, which are invisible to human eyes.Proxima Centauri flare

This artist's conception of a powerful stellar flare from Proxima Centauri shows an accompanying coronal mass ejection that's sending material out into space. Such an ejection of particles likely accompanied a flare on May 1, 2019.

S. Dagnello / NRAO / AUI / NSF

But don’t be too cavalier with the word “close,” as the distances involved are here still astounding: Proxima is 40,208,000,000,000 km, or 268,770 astronomical units (a.u.), from us. Don’t make any vacation plans just yet!

Proxima is about 13,000 a.u. from its companions, circling them every 550,000 years in a slow and enormous orbit. The laws of celestial mechanics dictate that objects orbiting close to their parent star (Mercury, for example) travel faster than those orbiting at a great distance (like Neptune), so Proxima’s slow pace is a product of its vast distance.

Red dwarf stars are the most common type of star in the universe, so it’s not surprising to find Proxima (and Barnard’s Star) in our immediate vicinity. Proxima Centauri has a feisty personality, as it’s prone to occasional fiery outbursts of stellar flares, but it’s also an enduring star. Because of their small size, red dwarfs are cooler, and they don’t expend their fuel sources as rapidly as larger stars. So even though they have fewer atoms to fuse, the rate of consumption is so slow that these fuel sources can last a very long time. If Proxima Centauri continues its fusion at the current rate, it will continue shining for several trillion years!This artist’s impression shows what the sky might look like on Proxima Centauri b if the planet has a surface and an atmosphere.

ESO / M. Kornmesser

Proxima hosts two exoplanets: a rocky but likely airless world dubbed Proxima Centauri b, with a mass of about 1.27 Earths and an orbital period of just 11 days, and Proxima Centauri c, a world probably around the size of Neptune.A good chart is essential for identifying Proxima Centauri within the densely packed Milky Way star field.

Sky & Telescope:

It’s possible that future technology could allow for robotic exploration of nearby stars, and Proxima Centauri would make an interesting candidate. But you don’t have to wait for the future to start your own exploration of the nearby red dwarf. You just need the right location and — just as importantly — the right telescope.You’ll need to be south of roughly 30°N latitude to see Proxima. The further south you go, the higher the dim star rises out of the turbulent air near the horizon, and the easier it will be to see. So while it’s theoretically possible to see Proxima from southern U.S. mainland states like Florida or Texas, for stargazers in Australia, Central and South America, and parts of Africa and Asia, the view should be excellent.

Proxima can make for an interesting telescopic challenge, especially for experienced amateurs who are used to finding dim objects by “star-hopping.” The binary A and B pair are easy enough to split visually, but Proxima is separated a full 2° from Alpha Centauri AB, so it requires a bit of searching. How big will your telescope need to be? While local atmospheric and light pollution conditions will always play a factor, a 6-inch or larger reflector should be able to pull in the 11th-magnitude Proxima. This can be a great project for astrophotographers as well, who can better record the star’s red color.

Proxima may not look like much through your telescope, especially compared to the much brighter A and B stars, but it can be interesting to reach out and gather the light of this dim star that is so very far — but not that far — away. Have you ever spotted our nearest stellar neighbor?

The Beams🌝(rays,light,warmth,sun☀️)

 The Sun is the star at the center of the Solar System. It is a massive, hot ball of plasma, inflated and heated by energy produced by nuclear fusion reactions at its core. Part of this internal energy is emitted from its surface as light, ultraviolet, and infrared radiation, providing most of the energy for life on Earth.

          DEATELS 

73.46% hydrogen

24.85% helium

0.77% oxygen

0.29% carbon

0.16% iron

0.12% neon

0.09% nitrogen

0.07% silicon

☀️☀️☀️☀️☀️

0.05% magnesium

0.04% sulphur

Rotation characteristics

Obliquity

7.25°[5]

(to the ecliptic)

67.23°

(to the galactic plane)

Right ascension

of North pole

286.13°

19 h 4 min 30 s

Declination

of North pole

+63.87°

63° 52' North

Sidereal rotation period

25.05 days at equator

25.38 days at 16° latitude

34.4 days at poles

Rotation velocity

(at equator)

1.997 km/s

• 
  

The Sun moves around the Galic Center of the Milky Way, at a distance of 26,660 light-years. From Earth, it is on average 1 AU (1.496×108 km) or about 8 light-minutes away. Its diameter is about 1,391,400 km (864,600 mi; 4.64 ls), 109 times that of Earth or 4 lunar distances. Its mass is about 330,000 times that of Earth, making up about 99.86% of the total mass of the Solar System. Roughly three-quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.

The Sun is a G-type main-sequence star (G2V), informally called a yellow dwarf, though its light is actually white. It formed approximately 4.6 billionyears ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process.

Every second, the Sun's core fuses about 600 million tons of hydrogen into helium, and in the process converts 4 million tons of matter into energy. This energy, which can take between 10,000 and 170,000 years to escape the core, is the source of the Sun's light and heat. Far in the future, when hydrogen fusion in the Sun's core diminishes to the point where the Sun is no longer in hydrostatic equilibrium, its core will undergo a marked increase in density and temperature which will push its outer layers to expand, eventually transforming the Sun into a red giant. This process will make the Sun large enough to render Earth uninhabitable approximately five billion years from the present. After this, the Sun will shed its outer layers and become a dense type of cooling star (a white dwarf), and no longer produce energy by fusion, but still glow and give off heat from its previous fusion for trillions of years. After that it might become a super dense hypothetical black dwarf, giving off no more energy.

The enormous effect of the Sun on Earth has been recognized since prehistoric times; the Sun was thought of by some cultures as a deity. The synodic rotation of Earth and its orbit around the Sun are the basis of some solar calendars. The predominant calendar in use today is the Gregorian calendar, which is based upon the standard 16th-century interpretation of the Sun's observed movement as actual movement.

.Venus, the Morning Star and Evening Star⭐why is this call a star actually 🪐 Let's find it out🌌🌠

 Venus is the first celestial body to become visible in the sky at evening and is the last one to disappear from the sky at sunrise. This is why it is known as the Morning and the Evening star.Venus, the Morning Star and Evening Star.

One of the nicknames of Venus is “the Morning Star”. It’s also known as the Evening Star. Of course, Venus isn’t a star at all, but a planet. So why does Venus have these nicknames?

The orbit of Venus is inside the orbit of Earth. Unlike the outer planets, Venus is always relatively close to the Sun in the sky. When Venus is on one side of the Sun, it’s trailing the Sun in the sky and brightens into view shortly after the Sun sets, when the sky is dark enough for it to be visible. When Venus is at its brightest, it becomes visible just minutes after the Sun goes down. This is when Venus is seen as the Evening Star.

When Venus is on the other side of the Sun, it leads the Sun as it travels across the sky. Venus will rise in the morning a few hours before the Sun. Then as the Sun rises, the sky brightens and Venus fades away in the daytime sky. This is Venus the Morning Star.

The ancient Greeks and Egyptians thought that Venus was actually two separate objects, a morning star and an evening star. The Greeks called the morning star Phosphoros, “the bringer of light”; and they called the evening star Hesperos, “the star of the evening”. A few hundred years later, the Hellenistic Greeks realized that Venus was actually a single object.

We have done several articles on Universe Today encouraging readers to go out and see Venus the Morning Star. And here’s what Venus looks like in a telescope.

We have also recorded a whole episode of Astronomy Cast that’s just about planet Venus. Listen to it here, Episode 50: Venus.

The ancient Greeks and Egyptians thought that Venus was actually two separate objects, a morning star and an evening star. The Greeks called the morning star Phosphoros, “the bringer of light”; and they called the evening star Hesperos, “the star of the evening”. A few hundred years later, the Hellenistic Greeks realized that Venus was actually a single object.

We have done several articles on Universe Today encouraging readers to go out and see Venus the Morning Star. And here’s what Venus looks like in a telescope.

Want more information on Venus? Here’s a link to Hubblesite’s News Releases about Venus, and here’s NASA’s Solar System Exploration Guide to Venus.

হেলির ধুমকেতু (Halley's Comet)

 Halley's Comet, Comet Halley, or sometimes simply Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 75–79 years.[1] Halley is the only known short-period comet that is regularly visible to the naked eye from Earth, and thus the only naked-eye comet that can appear twice in a human lifetime.[15] It last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061.

                                  Discovery

Discovered by

Prehistoric (observation)

Edmond Halley (recognition of periodicity)

Discovery date

1758 (first predicted perihelion)

Orbital characteristics[1]

Epoch 4 August 2061 (2474040.5)

Aphelion

35.14 au

(aphelion: 9 December 2023)

Perihelion

0.59278 au[4]

(last perihelion: 9 February 1986)

(next perihelion: 28 July 2061)

Semi-major axis

17.737 au

Eccentricity

0.96658

Orbital period (sidereal)

74.7 yr

75y 5m 19d (perihelion to perihelion)

Mean anomaly

0.07323°

Inclination

161.96°

Longitude of ascending node

59.396°

Time of perihelion

28 July 2061

≈27 March 2134

Argument of perihelion

112.05°

Earth MOID

0.075 au (11.2 million km)

(epoch 1968)

TJupiter

-0.598

                    Physical characteristics

Dimensions

15 km × 8 km

Mean diameter

11 km

Mass

2.2×1014 kg

Mean density

0.6 g/cm3 (average)

0.2–1.5 g/cm3 (est.)

Escape velocity

~0.002 km/s

Synodic rotation period

2.2 d (52.8 h) (?)

Albedo

0.04

Apparent magnitude

28.2 (in 2003)

Black hole☄️what is Black hole,,what's the secret of it..Let's find out.🌌🪐

 

A black hole is a region of spacetime where gravity is so strong that nothing, including light and other electromagnetic waves, has enough energy to escape it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.

The singularity at the center of a black hole is the ultimate no man's land: a place where matter is compressed down to an infinitely tiny point, and all conceptions of time and space completely break down. And it doesn't really exist. Something has to replace the singularity, but we're not exactly sure what.

What’s inside a black hole?

The short answer is that no one knows!

“In some ways that’s one of the most profound questions in physics,” said University of Chicago Prof. Daniel Holz. “There are not many cases in physics where we simply cannot predict what happens, but this is one of them.”

Black holes have two parts. There is the event horizon, which you can think of as the surface, though it’s simply the point where the gravity gets too strong for anything to escape. And then, at the center, is the singularity. That’s the word we use to describe a point that is infinitely small and infinitely dense.

We have a good understanding of what the event horizon looks like, thanks to the laws of general relativity. But as you get close to the singularity itself, we lose the ability to even predict what it looks like.

“Very near the singularity, one would expect quantum effects to become important. However, we don't yet have a quantum theory of gravity (or, at least, one capable of reliably making such predictions), so we just don't know the correct description of the singularity—or even whether it really is a singularity,” said University of Chicago Prof. Robert Wald.

Scientists think that black holes eventually will explode, but it will take many, many times longer than the current age of the universe for that to happen. What will it look like when that happens? That’s another big mystery.

“Maybe there’s a little nugget left behind containing all of the information that fell into the black hole, maybe there’s a portal to a new universe, maybe the information is just gone forever; we simply don’t know,” said Holz.

(If all of this is unsatisfying, know that it keeps scientists awake at night, too.)

How do black holes form?

Scientists know about one way that black holes form, but there may be others.

One way to make a black hole is to have a massive star collapse at the end of its life. Prof. Subrahmanyan Chandrasekhar was the first to calculate that when a massive star burns up all its fuel, it will collapse. The idea was ridiculed at first, but other scientists calculated that the star continues forever to fall inward toward its center—thus creating what we called a black hole.

Black holes can grow more massive over time as they “eat” gas, stars, planets and even other black holes!

There’s another type of black hole called a supermassive black hole. These are way too massive to have been created by one star collapsing; it’s still a mystery how they form. Black holes can eat other black holes, so it’s possible that the supermassive ones are made of many small black holes merged together. “Or perhaps these big black holes were especially hungry, and ate so much of their surroundings that they grew to enormous size,” said Prof. Holz. But we can see these supermassive black holes formed very early on in the universe—maybe too early to have been made by stars getting old enough to collapse—so it’s possible there’s some other way to make a black hole that we don’t know about yet.

What is a supermassive black hole?

There are two kinds of black holes: star-sized black holes and supermassive black holes.

Supermassive black holes are so named because they contain on the order of millions to billions times the mass of our sun.

As far as we can tell, nearly every galaxy in the universe has one of these supermassive black holes sitting right at its center like a seed. And they are correlated—a bigger galaxy has a bigger black hole, and a smaller galaxy has a smaller black hole. All of this makes scientists think these supermassive black holes have something to do with how the galaxies formed. But that relationship is still a mystery, and so is how the supermassive black holes formed in the first place.

Our “neighborhood” supermassive black hole, the one at the center of our own Milky Way galaxy, is called Sagittarius A* (pronounced A-star). It’s about 15 million miles across and contains the equivalent of 4 million suns’ worth of mass. Don’t worry; it’s much too far away to pose any danger to Earth.

What do black holes eat?

Contrary to what you may have seen in movies, black holes don’t actually “suck” things in. For example, there are actually stars orbiting the supermassive black hole at the center of our galaxy, and they’ll keep orbiting without falling in unless something else disturbs them. An object really has to fall right into.

Big Bang Theory🪐

 This article is about the  The Big Bang Theory. .🪐☄️

The Big Bang event is a physical theory that describes how the universe expanded from an initial state of high density and temperature. It was first proposed in 1927 by Roman Catholic priest and physicist Georges Lemaître. Various cosmological models of the Big Bang explain the evolution of the observable universe from the earliest known periods through its subsequent large-scale form.These models offer a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background (CMB) radiation, and large-scale structure. The overall uniformity of the Universe, known as the flatness problem, is explained through cosmic inflation: a sudden and very rapid expansion of space during the earliest moments. However, physics currently lacks a widely accepted theory of quantum gravity that can successfully model the earliest conditions of the Big Bang.

The theory dates back to 1922, with Russian physicist Alexander Friedmann creating a set of equations showing that the end of the universe depends on its density. It could either expand or contract rather than stay stable. With enough matter, gravity could stop the universe's expansion and eventually reverse it. This reversal would result in the universe collapsing on itself, not too dissimilar to a black hole.

The ending of the Big Crunch would get filled with radiation from stars and high-energy particles; when this is condensed and blueshifted to higher energy, it would be intense enough to ignite the surface of stars before they collide. In the final moments, the universe would be one large fireball with a temperature of infinity, and at the absolute end, neither time, nor space would remain.

Timeline of the expansion of the universe, where space, including hypothetical non-observable portions of the universe, is represented at each time by the circular sections. On the left, the dramatic expansion occurs in the inflationary epoch; and at the center, the expansion accelerates (artist's concept; neither time or size are to scale).

Crucially, these models are compatible with the Hubble–Lemaître law—the observation that the farther away a galaxy is, the faster it is moving away from Earth. Extrapolating this cosmic expansion backwards in time using the known laws of physics, the models describe an increasingly concentrated cosmos preceded by a singularity in which space and time lose meaning (typically named "the Big Bang singularity").In 1964 the CMB was discovered, which convinced many cosmologists that the competing steady-state model of cosmic evolution was falsified, since the Big Bang models predict a uniform background radiation caused by high temperatures and densities in the distant past. A wide range of empirical evidence strongly favors the Big Bang event, which is now essentially universally accepted. Detailed measurements of the expansion rate of the universe place the Big Bang singularity at an estimated 13.787±0.020 billion years ago, which is considered the age of the universe.

There remain aspects of the observed universe that are not yet adequately explained by the Big Bang models. After its initial expansion, the universe cooled sufficiently to allow the formation of subatomic particles, and later atoms. The unequal abundances of matter and antimatter that allowed this to occur is an unexplained effect known as baryon asymmetry. These primordial elements—mostly hydrogen, with some helium and lithium—later coalesced through gravity, forming early stars and galaxies. Astronomers observe the gravitational effects of an unknown dark matter surrounding galaxies. Most of the gravitational potential in the universe seems to be in this form, and the Big Bang models and various observations indicate that this excess gravitational potential is not created by baryonic matter, such as normal atoms. Measurements of the redshifts of supernovae indicate that the expansion of the universe is accelerating, an observation attributed to an unexplained phenomenon known as dark energy.

#bigbang

#theory

Milky way(Nabula)🌌☄️

 The Milky Way Galaxy is a significant place. Our solar system, including the Sun, Earth, and all the other planets, is within one of the spiral arms in the disk of the Milky Way Galaxy. Most of the stars we see in the sky are relatively nearby stars that are also in this spiral arm. Earth is about 26,000 light-years from the center of the galaxy, a little more than halfway out from the center of the galaxy to the edge.Just as Earth orbits the Sun, the Sun and solar system orbit the center of the Galaxy. One orbit of the solar system takes about 225 to 250 million years. The solar system has orbited 20 to 25 times since it formed 4.6 billion years ago. Astronomers have recently found that at the center of the Milky Way, and most other galaxies, is a supermassive black hole, though a black hole cannot be seen a dark, clear night, you will see a milky band of light stretching across the sky. This band is the disk of a galaxy, the Milky Way Galaxy, is our galaxy and is made of millions of stars along with a lot of gas and dust.

Shape and Size

Although it is difficult to know what the shape of the Milky Way Galaxy is because we are inside of it, astronomers have identified it as a typical spiral galaxy containing about 10Like other spiral galaxies, our galaxy has a disk, a central bulge, and spiral arms. The disk is about 100,000 light-years across and 3,000 light-years thick. Most of the Galaxy’s gas, dust, young stars, and open clusters are in the disk. What data and evidence do astronomers find that lets them know that the Milky Way is a spiral galaxy?

The shape of the galaxy as we see it.

The velocities of stars and gas in the galaxy show a rotational motion.

The gases, color, and dust are typical of spiral galaxies.

The central bulge is about 12,000 to 16,000 light-years wide and 6,000 to 10,000 light-years thick. The central bulge contains mostly older stars and globular clusters. Some recent evidence suggests the bulge might not be spherical, but is instead shaped like a bar. The bar might be as long as 27,000 light-years long. The disk and bulge are surrounded by a faint, spherical halo, which also includes old stars and globular clusters. Astronomers have discovered that there is a gigantic black hole at the center of the galaxy.0 billion to 400 billion stars.

#nabula

#starshome

The universes 🪐🌌

 The universe is all of space and time[a] and their contents. It comprises all of existence, any fundamental interaction, physical process and physical constant, and therefore all forms of energy and matter, and the structures they form, from sub-atomic particles to entire galaxies. Space and time, according to the prevailing cosmological theory of the Big Bang, emerged together 13.787±0.020 billion years ago,and the universe has been expanding ever since. Today the universe has expanded into an age and size that is physically only in parts observable as the observable universe, which is approximately 93 billion light-years in diameter at the present day, while the spatial size, if any, of the entire universe is unknown.

    #Humbble ultra-deep

The Hubble Ultra-Deep Field image shows some of the most remote galaxies visible to present technology (diagonal is ~1/10 apparent Moon diameter)

Age (within ΛCDM model)

13.787 ± 0.020 billion years

Diameter

Unknown.[3] Observable universe: 8.8×1026 m (28.5 Gpc or 93 Gly)

Mass (ordinary matter)

At least 1053 kg

Average density (with energy)

9.9×10−27 kg/m3

Average temperature

2.72548 K (−270.4 °C, −454.8 °F)

Main contents

Ordinary (baryonic) matter (4.9%)

Dark matter (26.8%)

Dark energy (68.3%)

Shape

Flat with 4‰ error margin

#universes

#unique

The Big Crunch🌌

 The Big Crunch is a hypothetical scenario for the ultimate fate of the universe, in which the expansion of the universe eventually reverses and the universe recollapses , ultimately causing the cosmic scale factor to reach zero, an event potentially followed by a reformation of the universe starting with another Big Bang. The vast majority of evidence indicates that this hypothesis is not correct. Instead, astronomical observations show that the expansion of the universe is accelerating rather than being slowed by gravity, suggesting that a Big Freeze is more likely.However, there are new theories that suggest that a "Big Crunch-style" event could happen by the way of a dark energy fluctuation; however, this is still being debated amongst scientists.

The theory dates back to 1922, with Russian physicist Alexander Friedmann creating a set of equations showing that the end of the universe depends on its density. It could either expand or contract rather than stay stable. With enough matter, gravity could stop the universe's expansion and eventually reverse it. This reversal would result in the universe collapsing on itself, not too dissimilar to a black hole.

The ending of the Big Crunch would get filled with radiation from stars and high-energy particles; when this is condensed and blueshifted to higher energy, it would be intense enough to ignite the surface of stars before they collide.[6] In the final moments, the universe would be one large fireball with a temperature of infinity, and at the absolute end, neither time, nor space would remain.

#bigcrunch

*theory 

Artificial intelligence (AI)

 

Artificial intelligence (AI) is the intelligence of machines or software, as opposed to the intelligence of humans or animals. It is a field of study in computer science that develops and studies intelligent machines. Such machines may be called AI's.

AI technology is widely used throughout industry, government, and science. Some high-profile applications are: advanced web search engines (e.g., Google Search), recommendation systems (used by YouTube, Amazon, and Netflix), understanding human speech (such as Google Assistant, Siri, and Alexa), self-driving cars (e.g., Waymo), generative and creative tools (ChatGPT and AI art), and superhuman play and analysis in strategy games (such as chess and Go).

Alan Turing was the first person to conduct substantial research in the field that he called Machine Intelligence.[2] Artificial intelligence was founded as an academic discipline in 1956.[3] The field went through multiple cycles of optimism[4][5] followed by disappointment and loss of funding.[6][7] Funding and interest vastly increased after 2012 when deep learning surpassed all previous AI techniques,[8] and after 2017 with the transformer architecture.[9] This led to the AI spring of the 2020s, with companies, universities, and laboratories overwhelmingly based in the United States pioneering significant advances in artificial intelligence.

The various sub-fields of AI research are centered around particular goals and the use of particular tools. The traditional goals of AI research include reasoning, knowledge representation, planning, learning, natural language processing, perception, and support for robotics.[a] General intelligence (the ability to complete any task performable by a human) is among the field's long-term goals.

To solve these problems, AI researchers have adapted and integrated a wide range of problem-solving techniques, including search and mathematical optimization, formal logic, artificial neural networks, and methods based on statistics, operations research, and economics.[b] AI also draws upon psychology, linguistics, philosophy, neuroscience and other fields.

We know everythimg has good or bed side's. As well AI also.

What are the advantages and disadvantages of artificial intelligence?

Artificial neural networks and deep learning AI technologies are quickly evolving, primarily because AI can process large amounts of data much faster and make predictions more accurately than humanly possible.

While the huge volume of data created on a daily basis would bury a human researcher, AI applications using machine learning can take that data and quickly turn it into actionable information. As of this writing, a primary disadvantage of AI is that it is expensive to process the large amounts of data AI programming requires. As AI techniques are incorporated into more products and services, organizations must also be attuned to AI's potential to create biased and discriminatory systems, intentionally or inadvertently.

Advantages of AI

The following are some advantages of AI.

*Good at detail-oriented jobs. AI has proven to be just as good, if not better than doctors at diagnosing certain cancers, including breast cancer and melanoma.

*Reduced time for data-heavy tasks. AI is widely used in data-heavy industries, including banking and securities, pharma and insurance, to reduce the time it takes to analyze big data sets. Financial services, for example, routinely use AI to process loan applications and detect fraud.

*Saves labor and increases productivity. An example here is the use of warehouse automation, which grew during the pandemic and is expected to increase with the integration of AI and machine learning.

*Delivers consistent results. The best AI translation tools deliver high levels of consistency, offering even small businesses the ability to reach customers in their native language.

Can improve customer satisfaction through personalization. AI can personalize content, messaging, ads, recommendations and websites to individual customers.

AI-powered virtual agents are always available. AI programs do not need to sleep or take breaks, providing 24/7 service.

Disadvantages of AI

•The following are some disadvantages of AI.

Expensive.

•Requires deep technical expertise.

•Limited supply of qualified workers to build AI tools.

•Reflects the biases of its training data, at scale.

•Lack of ability to generalize from one task to another.

•Eliminates human jobs, increasing unemployment rates.

•Strong AI vs. weak AI

AI can be categorized as weak or strong.

Weak AI, also known as narrow AI, is designed and trained to complete a specific task. Industrial robots and virtual personal assistants, such as Apple's Siri, use weak AI.

Strong AI, also known as artificial general intelligence (AGI), describes programming that can replicate the cognitive abilities of the human brain. When presented with an unfamiliar task, a strong AI system can use fuzzy logic to apply knowledge from one domain to another and find a solution autonomously. In theory, a strong AI program should be able to pass both a Turing test and the Chinese Room argument.

What are the 4 types of artificial intelligence?

Arend Hintze, an assistant professor of integrative biology and computer science and engineering at Michigan State University, explained that AI can be categorized into four types, beginning with the task-specific intelligent systems in wide use today and progressing to sentient systems, which do not yet exist. The categories are as follows.

Type 1: Reactive machines. These AI systems have no memory and are task-specific. An example is Deep Blue, the IBM chess program that beat Garry Kasparov in the 1990s. Deep Blue can identify pieces on a chessboard and make predictions, but because it has no memory, it cannot use past experiences to inform future ones.

Type 2: Limited memory. These AI systems have memory, so they can use past experiences to inform future decisions. Some of the decision-making functions in self-driving cars are designed this way.

Type 3: Theory of mind. Theory of mind is a psychology term. When applied to AI, it means the system would have the social intelligence to understand emotions. This type of AI will be able to infer human intentions and predict behavior, a necessary skill for AI systems to become integral members of human teams.

Type 4: Self-awareness. In this category, AI systems have a sense of self, which gives them consciousness. Machines with self-awareness understand their own current state. This type of AI does not yet exist