Pengertian Teropong atau Teleskop

Teropong atau Teleskop adalah alat optik yang digunakan untuk melihatbenda-benda yang sangat jauh seperti gunung dan bintang agar tampak lebihdekat dan jelas. Meskipun teropong sudah digunakan sejak abad ke ² 17namun sampai sekarang tidak seorang pun yakin siapa yang pertama kalimenemukan teropong. Memang pada tanggal 2 oktober 1608 Hans Lippersheypernah mecoba mempatenkan teleskop yang dibuatnya, tetapi ditolak olehdewan penilai. Kemudian pada tahun 1609 Galileo membuat sebuah teleskop yang sekarang dikenal dengan sebutan teropong panggung. Setelah itu iamembuat banyak macam teleskop dan mendapatkan banyak penemuan dalambidang astronomis yang membuatnya terkenal. Teropong dibagi menjadi duakelompok yaitu :

1.      Teropong Bias, yang terdiri dari beberapa lensa2. 

2.      Teropong pantul, yang terdiri dari beberapa cermin dan lensa

“Teropong Bias”

Teropong bias menggunakan lensa sebagai obyektif untuk membiaskan cahaya.Beberapa contoh teropong bias adalah :

1.      Teropong bintang atau teropong astronomib.

2.      Teropong bumic.

3.      Teropong panggung.

4.      Teropong prisma atau binokuler

 

Pengertian :

1.      Teropong Bintang

 Teropong bintang atau teropong astronomi digunakanuntuk mengamati benda-benda angkasa luar. Teropong bintang menggunakandua buah lensa positif, masing-masing sebagai lensa obyektif dan lensaokuler. Berbeda dengan mikroskop, pada teropong jarak focus lensa obyektiflebih besar dari jarak focus lensa okuler.

2.      Teropong Bumi

 Teropong bumi yang disebut juga teropong medan atauteropong yojana menghasilkan bayangan akhir yang tegak terhadap arahbenda semula. Hal ini dapat diperoleh dengan menggunakan lensa cembungketiga yang disisipkan di antara lensa obyektif dan lensa okuler. Lensacembung ketiga hanya berfungsi membalik bayangan tanpa perbesaran, olehkarena itu lensa ini disebut lensa pembalik.

 

3.      Teropong panggung atau Teropong Galilei

 Teropong panggung atau teropong Galilei disebut jugateropong Belnada atau teropong tonil. Teropong ini menghasilkan bayanganakhir yang tegak dan diperbesar dengan menggunakan dua buah lensa, lensapositif sebagai lensa obyektif dan lensa negatif sebagai lensa okuler.

4.      Teropong Prisma

 Penggunaan lensa pembalik untuk menghasilkanbayangan akhir yang tegak mengakibatkan teropong bumi menjadi relativepanjang. Untuk menghindarinya maka lensa pembalik diganti denganpenggunaan dua prisma siku-siku sama kaki yang disisipkan di antara lensaobyektif dan lensa okuler. Prisma-prisma tersebut digunakan untukmembalikkan bayangan dengan pemantulan sempurna.

“Teropong Pantul”

Teropong pantul merupakan teropong bintang yang disusun dari bahan cermin cekung, cermin datar dan lensa.  Fungsi lensa obyektif diganti dengan cermin cekung. Perbesaran bayangan pada teropong ini sama dengan teropong bintang bias. Perbesaran bayangan pada teropong ini sama dengan teropong bintang bias. Teropong ini lebih murah dan mudah dibuat dari teropong bias.

Ada beberapa contoh teropong pantul, yaitu teropong Cassegrain, teropong Newtonian, teropong Gregorian.

Sejarah Teleskop atau Teropong

 Perkembangan ilmu pengetahuan dan teknologi pengamatan pada lima abadlalu membawa manusia untuk memahami benda-benda langit terbebas dariselubung mitologi. Galileo Galilei (1564-1642) dengan teleskop refraktornyamampu menjadikan mata manusia "lebih tajam" dalam mengamati benda langit yang tidak bisa diamati melalui mata biasa.

Karena teleskop Galileo bisa mengamati lebih tajam, ia bisa melihat berbagai perubahan bentuk penampakan Venus, seperti Venus Sabit atau Venus Purnama sebagai akibat perubahan posisi Venus terhadap Matahari. Teleskop Galileo terus disempurnakan oleh ilmuwan lain seperti Christian Huygens(1629-1695) yang menemukan Titan, satelit Saturnus, yang berada hampir 2kali jarak orbit Bumi-Yupiter.

Perkembangan teleskop juga diimbangi pula dengan perkembangan perhitungan gerak benda-benda langit dan hubungan satu dengan yang lainmelalui Johannes Kepler (1571-1630) dengan Hukum Kepler. Dan puncaknya,Sir Isaac Newton (1642-1727) dengan hukum gravitasi. Dengan dua teoriperhitungan inilah yang memungkinkan pencarian dan perhitungan benda-benda langit selanjutnya .

MAKE UP, PINK MOUSE AND PUPPIES

I suppose you haven't guessed yet (looking at the pictures and the title) what this post is going to be about. Surprise, surprise - beauty products. Since lately I've been getting quite a lot of requests to show you my current makeup favourites and a few days ago I bought this cute mouse-alike makeup bag (honestly speaking, there are times when I just can't bear the cuteness of it anymore - I mean, carrying it in my bag it's like carrying a bunch of puppies with big brown loving eyes - the type of puppies you see on mugs or notebooks, sweet to an absolute death), I decided to write a little bit about things I use, things I like, things I can recommend without a doubt. I'm very lucky because I have a chance to use and try out many products but at the end of the day, when I empty all of the 'luxurious' stuff and have to buy something on my own, I always look for a cheaper alternative in a drugstore. I guess, before you spend a lot of money on a beauty product, it's good to check whether you can't have pretty much the same and pay ten times less. Of course, it's a personal preference. I, for instance, from time to time I take out my savings and when my birthday's coming (seriously, any excuse will go), I buy myself something like YSL lipstick. There's just a funny luxurious mist around it. It's called the magic of brand. No, it's actually called having your brain switched off for a moment. But that  is just the way it is.

 Last summer, when I wrote that huge post about lotions and potions, I told you that beauty for me is a topic that just opens our mouth. I openly admit that I really love beauty products, however weird and psycho it sounds, I just love looking at them. Honestly, I'm not that much into smearing all of the products on my face, I can't really use eyeshadows, I don't care about blush. I just adore looking at all this stuff. And having said that, I think it's high time I told you about my next obsession. Guys, it's really like a level-up of our friendship cause it's quite mental of me (not that my every mania is mental). I'm a Sephora addict. Not in a way, I go to Sephora and I buy ten thousand products and I leave. I don't actually buy anything. I just go there for a walk. I mean,  I just go there and I stand there. And I look at all these products. Everything is so organized, everything smells so nicely. I just feel so secure there. I told you it is mental. And when Holly Golightly would have her breakfast at Tiffany's because she just felt right there, I would totally eat it in Sephora.

 OK, since we are extremely close friends after my confession, it's time to present you my favorite products. I'll start with the only thing that I haven't found a cheaper alternative for. It's my tinted moisturizer. Dior Hydra Life Pro Youth Skin Tint in shade #1 - congrats for the longest name ever. I have extremely sensitive skin, it gets reds when it cold, it gets irritated when it hot, it doesn't like awful lot of ingredients and I swear, searching for something that my skin would tolerate was a traumatic experience (I mean it). I tried everything, from drugstore to high end, from foundation to powder and tinted moisturizer and I found this one only working and being super gentle for my skin. Next is a very nice powder (Chanel Les Beiges Healthy Glow Sheer Powder nr 50 - congrats for the longest name ever part 2)  that I got thanks to Chanel company. I use it only on my cheeks as a bronzer, I think it's the product with the biggest lasting power I've had plus, it smells so good. It smells so good I could smell it all day. But I don't, because it would be just...weird. And inappropriate. And that's it for the face. When it comes to eyes, I use two products - brown eyepencil and mascara. I really like Miss Sporty Kohl Kajal in 002 and Maybelline The Falsies Flared mascara. Since I have extremely dry lips, lately I've been using an awful lot of lipbalms. I also have an awful lot of vanilla candles in my room. I just love this smell. So I went to a drugstore one day, I saw Nivea Lip Butter in Vanilla and when I thought that finally my dreams would come true and I would be able to carry a vanilla scent everywhere, I died. I mean, I didn't, but I ended up buying it and loving it. It smells just like my candles (and that makes me super happy) and when it comes to moisturizing, it's far better than Carmex (that makes me super happy as well). And that would be all for my everyday makeup.

 When it comes to my nails, most of the time I stick to a very neutral nail polish like the one from Rimmel (Rimmel Lycra Pro 444 French Lingerie - these names are killing me, who wants to wear the color of their panties on their nails. It's quite confusing). I also really like Essie nail polish ( Essie 89 Raspberry) that I got from lovely girls from a shop 30 ml. Its color is the prettiest pink plus its name...is the prettiest too :)

A couple of months ago I told you I hated red lipsticks. Well, I haven't changed my mind, because I still don't like them. I don't like the texture of a lipstick and I don't like that you have to think about it all the time. Having said that, I found something that immediately became my holy grail in make up collection. I'll probably rave about it till the end of my life. It's a lip stain that looks like a big crayon. When you put in on your lips, it just looks you've got the prettiest shade of red on them but you can't really see any product texture-wise. It's invisible, it's stays forever, it doesn't dry out your lips. It's literally perfect. I don't really use to school, but sometimes I like to put it on after classes or during the weekends. It actually came to me in a GlossyBox and I couldn't find it in any shops in Poland. It's called Jelly Pong Pong Lip Blush. So when I run out of it, I'll be crying so much. So much. Or I'll order it online.
 So that's all. Let me know in the comments below what are your favourites, cause you know I' m dying to know it (not really dying, but as a beuty freak, I' d love to know it!)
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