Astronomi – Gök Bilimi

Archive for Temmuz, 2009

Merkür 167
Venüs 464°C
Dünya 14°C
Mars -63°C
Jüpiter -148°C
Satürn -178°C
Uranüs -215v
Neptün -226v
Plüton -300°C (Varsayılan)
Ceres -80°C (Varsayılan)
Eris -450°C (Varsayılan)

13 astronot servis istasyonu montajından önce grup fotorağfı veriyor.

Pazar sabahı, uzay mekiğinin robot kolu uluslar arası uzay istasyonunu yakaladı.Japon astronotlar uzay mekiği ile uluslararası uzay istasyonunun yük taşıyıcı panellerini kurular ve yükleri uzay mekiğinden uzay istasyonuna taşıdırlar. Daha sonra uzay istasyonuna uzay servis istasyonunun montajını yaptırlar. Montaj sırasında uzay yürüyüşüne çıkan astronotlar Chris Cassidy ve Tom Marshburn çarşamba günüde yürüyeceleri 6 saatin ardından toplan 14 saat uzay yürüyüşü yapmış olacaklar.

15 milyon ışık yılı uzağımızdaki Starburst Galaxy M94 nin görüntüleri.

In May 2009, seven astronauts aboard Space Shuttle Atlantis visited the Hubble Space Telescope for a final servicing mission. The drama of a shuttle flight with ambitious and challenging spacewalks that refreshed, repaired, and renewed astronomy’s most beloved telescope captured the attention of the world. The underlying reason for such heroic efforts is to enable Hubble to perform new science. Yet, these new capabilities are easily lost in the excitement as the adventure unfolds. This episode aims to remind us of the ultimate value of such an amazing mission.

Hubble press release:

• HubbleSite’s Servicing Mission 4 page

Notes

• This episode was filmed prior to the launch of the Servicing Mission 4, but was not posted for viewing until afterwards (we were kinda busy and absorbed in the proceedings during the mission). However, note that the content of the episode is not time sensitive, and speaks to the scientific capabilities that the mission enabled on Hubble. Both new instruments, Wide Field Camera 3 (WFC3) and Cosmic Origins Spectrograph (COS), were successfully installed. In addition, repairs to both the Advanced Camera for Surveys (ACS) and the Space Telescope Imaging Spectrograph (STIS) were also successful.
• The graph labeled “Hubble Survey Discovery Efficiency” is just one way to compare the capabilities of instruments on Hubble. You can find other comparisons, and each will have a slightly different focus and slightly different numbers for the improvements in the new instruments. No one number is definitive, but the sweeping generality that the new instruments enable Hubble to do significant new science can not be argued.
• One can argue that after Servicing Mission 4, Hubble will be the best it has ever been — not just in terms of the new instruments being better, but also in having more instruments operational. After launch, the telescope was hampered by the flaw in its mirror. Servicing Mission 1 installed COSTAR, the corrective optics, and that instrument has only now been removed during Servicing Mission 4. Hence, for 16 years, COSTAR has taken up an instrument slot, but not provided observing capabilities. If the NICMOS cooling system can be re-started, the observatory will return to its full capabilities with five science instruments.
• Many people have asked: given the improvements that WFC3 and COS will provide over ACS and STIS, why did we need to repair the older instruments? There are several answers. First, there is great value in redundancy. As we will not be able to return to Hubble once the space shuttle fleet is retired, having working backups in the event of a failure is a prudent move. Second, the older instruments are well-calibrated and familiar to scientists. Astronomers may choose to utilize the known instrument to speed-up their research or to retain consistent data processing as earlier observations. Third, the older instruments have different and complementary capabilities to the new instruments. The design of each instrument involves trade-offs, and each is optimized for a particular range of observations. Some observations can best or only be done with the older instruments, as they were optimized for that type of observing.

Image Notes

Space Shuttles Atlantis and Endeavor on the launch pads
Credit: NASA / Dimitri Gerondidakis

Astronauts working on the Hubble Space Telescope
Credit: NASA

Wide Field Camera 3 in the clean room
Credit: NASA

Animation illustrating the wavelengths that WFC3 observes
Credit: Greg Bacon, STScI

Drawing of the protoplanetary disk around the star NGC 1333-IRAS 4B
Credit: NASA/JPL-Caltech/R. Hurt (SSC)

Hubble Ultra Deep Field
Credit: NASA, ESA, S. Beckwith (STScI) and the HUDF Team

Core region of the Antennae Galaxies, 2006
Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration
Acknowledgment: B. Whitmore (Space Telescope Science Institute)

Cosmic Origins Spectrograph in the clean room
Credit: NASA

Visible light spectrum diagram
Credit: Philip Ronan

Visible spectrum of hydrogen
Credit: Jan Homann

Visible spectrum of helium
Credit: Jan Homann

Visible spectrum of neon
Credit: Jan Homann

Spectrum of the Sun
Credit: N.A.Sharp, NOAO/NSO/Kitt Peak FTS/AURA/NSF

Animation illustrating COS observations of large scale structure
Credit: Greg Bacon, STScI

Illustration of exploring the cosmic web with COS
Credit: NASA, ESA, A. Feild (STScI)

Hubble after Servicing Mission 3B
Credit: NASA

Johannes Kepler (pronounced /’k?pl?r/) (December 27, 1571 – November 15, 1630) was a German mathematician, astronomer and astrologer, and key figure in the 17th century scientific revolution. He is best known for his eponymous laws of planetary motion, codified by later astronomers based on his works Astronomia nova, Harmonices Mundi, and Epitome of Copernican Astrononomy. They also provided one of the foundations for Isaac Newton’s theory of universal gravitation.

During his career, Kepler was a mathematics teacher at a seminary school in Graz, Austria, an assistant to astronomer Tycho Brahe, the court mathematician to Emperor Rudolf II, a mathematics teacher in Linz, Austria, and an adviser to General Wallenstein. He also did fundamental work in the field of optics, invented an improved version of the refracting telescope (the Keplerian Telescope), and helped to legitimize the telescopic discoveries of his contemporary Galileo Galilei.

Kepler lived in an era when there was no clear distinction between astronomy and astrology, but there was a strong division between astronomy (a branch of mathematics within the liberal arts) and physics (a branch of natural philosophy). Kepler also incorporated religious arguments and reasoning into his work, motivated by the religious conviction that God had created the world according to an intelligible plan that is accessible through the natural light of reason.[1] Kepler described his new astronomy as “celestial physics”,[2] as “an excursion into Aristotle’s Metaphysics”,[3] and as “a supplement to Aristotle’s On the Heavens”,[4] transforming the ancient tradition of physical cosmology by treating astronomy as part of a universal mathematical physics.

Galileo Galilei (15 February 1564[2] – 8 January 1642)[1][3] was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations, and support for Copernicanism. Galileo has been called the “father of modern observational astronomy,”[4] the “father of modern physics,”[5] the “father of science,”[5] and “the Father of Modern Science.”[6] Stephen Hawking says, “Galileo, perhaps more than any other single person, was responsible for the birth of modern science.”[7]

The motion of uniformly accelerated objects, taught in nearly all high school and introductory college physics courses, was studied by Galileo as the subject of kinematics. His contributions to observational astronomy include the telescopic confirmation of the phases of Venus, the discovery of the four largest satellites of Jupiter, named the Galilean moons in his honour, and the observation and analysis of sunspots. Galileo also worked in applied science and technology, improving compass design.

Galileo’s championing of Copernicanism was controversial within his lifetime, when a large majority of philosophers and astronomers still subscribed (at least outwardly) to the geocentric view that the Earth remains motionless at the centre of the universe. After 1610, when he began supporting heliocentrism publicly, he met with bitter opposition from some philosophers and clerics, and two of the latter eventually denounced him to the Roman Inquisition early in 1615. Although he was cleared of any offence at that time, the Catholic Church nevertheless condemned heliocentrism as “false and contrary to Scripture” in February 1616,[8] and Galileo was warned to abandon his support for it—which he promised to do. When he later defended his views in his most famous work, Dialogue Concerning the Two Chief World Systems, published in 1632, he was tried by the Inquisition, found “vehemently suspect of heresy,” forced to recant, and spent the rest of his life under house arrest.

Üniversite bölümleri [değiştir]İTÜ Uzay Mühendisliği Bölümü

Ege Üniversitesi Astronomi ve Uzay Bilimleri Bölümü

Ege Üniversitesi Rasathanesi

Boğaziçi Üniversitesi Fizik Bölümü

Boğaziçi Üniversitesi Kandilli Rasathanesi ve Deprem Araştırma Enstitüsü

İstanbul Üniversitesi Astronomi ve Uzay Bilimleri Bölümü

İstanbul Üniversitesi Rasathanesi

Ankara Üniversitesi Astronomi ve Uzay Bilimleri Bölümü

Ankara Üniversitesi Rasathanesi

ODTÜ Havacılık ve Uzay Mühendisliği Bölümü

ODTÜ Fizik Bölümü Astrofizik Grubu

ODTÜ Amatör Astronomi Topluluğu

Erciyes Üniversitesi Astronomi ve Uzay Bilimleri Bölümü

Çanakkale Onsekiz Mart Üniversitesi Astrofizik Araştırma Merkezi (ÇAAM)

Sabancı Üniversitesi Fizik ve Astrofizik Bölümü

Akdeniz Üniversitesi Fizik Bölümü

İstanbul Kültür Üniversitesi Fizik Bölümü

Ondokuz Mayıs Üniversitesi Gözlemevi

Çukurova Üniversitesi UZAYMER – Uzay Bilimleri ve Güneş Enerjisi Araştırma ve Uygulama Merkezi

Feza Gürsey Enstitüsü

Bugüne dek bilinen en büyük kütleli kara delik keşfedildi.

Yahoo internet sitesinde ABD’nin 70 yıllık köklü bilim kurumu Jet Propulsion Laboratory’nin (Jet Motorları Araştırma Merkezi) kurulu olduğu California eyaletinde Pasadena kentinden bildirildiğine göre, astronomi katalog numarası “M87” olan kara delik, Dünya’nın 50 milyon ışık yılı uzağında bulunuyor.

Almanya’nın güneybatısında Baden-Württemberg eyaleti Heidelberg kentindeki Max Planck fen bilimleri “atomaltı ve dünya dışı fizik araştırma kurumu”, kara deliğin büyük kütlesini teyit etti. Texas Austin Üniversitesinden astrofizik uzmanı Karl Gebhardt ile Max Planck’dan Jens Thomas, “kara deliklerin gökadaların (galaksi) oluşumunda büyük yeni bilgiler sağlayacağını” söyledi.

M87 gökcisminin (kara deliğin) kütlesi öyle büyük ki, Güneş’in kütlesinin tam 6 milyar 400 milyon katı.
Amerikan Astronomi Cemiyetinin Pasadena’da yapılan 214. yıllık toplantısında, M87 hakkında bildiri okundu ve büyük ilgi uyandırdı. M87’ye ilişkin makaleler ve Pasadena bildirileri, yazın çıkacak Astrofizik Dergisinde yayımlanacak.

50 milyon ışık yılı uzakta M87’nin uzaklığına “yakınlardan örnek” şöyle verilebilir: Güneş Sistemimizin üyesi olduğu eliptik sarmal Samanyolu Gökadası, uzun çapında 110, kısa çapında 60 bin ışık yılı genişliğinde. Samanyolu’na en yakın galaksi olan Andromeda’nın çapının Samanyolu’nun iki mislinden fazla 250 bin ışık yılı genişliğinde olduğu tahmin ediliyor. 1 ışık yılının uzunluğu, 9,9 trilyon km.

KARA DELİK 
Kara delik, gökbiliminde, çekim alanı her türlü maddi oluşumun ve ışınımın kendisinden kaçmasına izin vermeyecek derecede güçlü olan, kütlesi büyük kainat cismi.
Kara deliklerin üç boyutlu olmadığı, sıfır hacimli olduğu kabul ediliyor.
Karadeliklerin içinde zamanın yavaş aktığı ya da akmadığı tahmin ediliyor.
Karadelikler, Einstein’ın genel görelilik kuramıyla tanımlandı, doğrudan gözlemlenememekle birlikte, çeşitli dalga boylarını kullanan dolaylı gözlem teknikleri sayesinde keşfedildi.
Bu teknikler, aynı zamanda çevrelerinde sürüklenen oluşumların da incelenme olanağını sağladı.
Bir karadeliğin çekim alanına kapılmış maddenin karadelikçe yutulmadan önce müthiş sıcaklık derecesine ulaştığı ve bu yüzden önemli miktarda X ışını yaydığı saptandı.
Böylece bir karadeliğin varlığı, kendisi ışık yaymasa da çevresinde bu tür icraat yarattığı için saptanabiliyor.
Bugün karadeliklerin varlığı, ilgili astrofizikçiler ve kuramsal fizikçilerden oluşan camianın hemen hemen tüm bireyleri tarafından onaylanarak kesinlik kazanmış durumda.
Güneşimizden çok daha büyük dev kütleli yıldızlar, kurama göre “öldüklerinde” çekim gücü sonsuz karadeliğe dönüşebiliyor.
PULSAR-KARA DELİK
Gökcisimlerinin en esrarengizlerinden pulsar (atarca), “kalp gibi atan” anlamına geliyor ve kara deliklerle bağlantılı.