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A Responsum Regarding Space Travel

On July 19, 2002, Col. Ilan Ramon, the first Israeli astronaut, is scheduled to blast off in the space shuttle Columbia from Cape Canaveral, Florida. A few weeks ago, Rabbi David Golinkin was interviewed by “ABC Nightly News with Peter Jennings” for a halakhic reaction to that event. The interview has not yet been broadcast. In the meantime, Rabbi Golinkin has written a formal responsum, which we are reprinting here below.

Question from Daphna Venyige, ABC News Correspondent in Israel: Colonel Ilan Ramon, the first Israeli astronaut, is scheduled to blast off on the “Columbia” in July. He is not particularly religious, but believes that as Israel’s first astronaut, he has a higher duty to consider. “I feel I am representing all Jews and all Israelis”, he said. How should he, and any future observant Jews, observe Kashrut, daily prayer, Shabbat, and festivals?

Responsum: In 1982, Rabbi Bezalel Stern of Vienna published a brief responsum regarding the proper time for prayer, Shabbat and festivals on a spaceship. He concluded by saying that “this is not currently an issue of halakhah l’ma’aseh (practical halakhah) but only of research for the sake of knowledge. Therefore, this brief note is sufficient for now.” In 1980, Rabbi Solomon Freehof (1892-1990) also thought that this was a theoretical question. Twenty years have passed and this is now a question of halakhah l’ma’aseh.

A. Theology

Two rabbis have discussed the theological aspects of space travel. Rabbi Freehof said that in Judaism, God is the God of the entire universe, and not just of “little earth and its people”. In the Birkhot Hashahar (early morning blessings) recited daily, we speak of God as Ribon Ha’olamim, master of worlds, in the plural.

We also recite Psalm 147:4 every day in the Pesukey D’zimra: “He numbers the stars and calls them each by name”. And in the Shabbat Torah service, we recite I Chronicles 29:11, which says that “all that is in Heaven and on Earth” belongs to God.

In 1962, Rabbi Nahum Rabinowitz was asked by a Congressman if, according to the Torah, it is permissible to travel to the moon and the stars and to colonize them. Rabbi Rabinowitz referred to Sanhedrin 109a, where R. Yirmiyahu ben Elazar discusses the generation of the Tower of Babel:

They split up into three parties. One said: Let us ascend and dwell there. The second said: Let us ascend and worship idols. And the third said: Let us ascend and wage war [with God]. Whereupon R. Nathan said: They were all bent on idolatry .

In other words, that generation was punished because their motive was to challenge God, which is a form of idol worship.

Similar reasoning is implied in Isaiah’s rebuke to “the king of Babylon” (Isaiah 14: 13-14): “And you said in your heart: I will ascend into Heaven; above the stars of God will I exalt my throne… I will ascend above the heights of the clouds, I will be like the Most High”. In other words, it is a sin to ascend to the heavens only if your motive is to “be like the Most High”.

Finally, Ben Sira said (3:22) “the things that have been permitted you, think thereupon”. The Maharsha, R. Shemuel Edeles, commented in the sixteenth century (Hagigah 13a, catchword B’mufla): “this is stated as an imperative as the researchers and philosophers have written, that a person should investigate his existence through studying whatever has been created in the Universe”.

In other words, Jews in space travel is permitted as long as the motive is research and investigation and not to challenge God’s authority in the universe.

B. Kashrut

Observant Jews are required to observe the laws of Kashrut whether they are on a boat or a plane, a submarine or a spaceship. Luckily, the issue of Kashrut has been resolved, since a company in Illinois already produces kosher food in self-heating sealed pouches for the army. (Jonathan Petre, The Sunday Telegraph, May 27, 2002).

C. Shabbat, Festivals and Daily Prayer

These are clearly the thorniest problems related to Jews in space travel. There is an old joke about the first Jewish astronaut who returns to earth utterly exhausted. He is asked: “What happened?” He replies: “shaharit, minhah, maariv, shaharit, minhah, maariv!” In other words, a spaceship orbits the earth once every ninety minutes. If each orbit is considered a “day” of twenty four hours, an observant astronaut would spend most of his time praying, and after every six orbits (or nine hours) he would have to observe Shabbat for ninety minutes. As a result, he would not only be exhausted, but have no time to do whatever he was sent to do!

There are five possible answers to this space-time dilemma:

1) In Sivan 5646 (June 1886), Rabbi Simha Halevi Bamberger of Aschaffenburg, Bavaria, was asked by his son Judah how he should observe Shabbat in Norway where it was mostly daylight at that time of year. He concluded that “you should not live there since it raises doubts about prayer, Shabbat and festival observances”. I do not believe that this is a proper approach, because if Judaism is a torat hayyim (a way of life), it must face new realities, and space travel and planetary travel will eventually become as common as plane travel is today.

2) Rabbi Levy Yitzhak Halperin, who is quoted in The Sunday Telegraph article, says “that Col. Ramon should be relieved of his obligations because he will not be experiencing Earth time”. I disagree. According to that logic, if a Jewish astronaut travels to Mars or the stars, he should stop observing Shabbat, festivals and daily prayer for five-ten years!

Indeed, “there is nothing new under the sun”. In 1934, Rabbi Yosef Mashash of Meknes, Morocco expressed opposition to Rabbi Halperin’s point of view. He was asked about an observant Jew who wanted to travel to “inner America” (South America?) where a day can last three months or more. What should he do about Shabbat and festivals? Someone showed him a handwritten responsum by a rabbi who said that one is not required to observe Shabbat in such places because the Torah ties Shabbat to “days”, as it is written (Exodus 34:21) “Six days you shall work, but on the seventh day you shall cease from labor”. “Days” have 24 hours, and since there are no such “days” there, there is no Shabbat. Rabbi Mashash reacted:

In my humble opinion, it is difficult to listen to this. If so, he will not have to observe all of the festivals, and he may eat hametz on Pesah, and eat on Yom Kippur because they are all called “day” or “days”; and any Jew who goes there can change his religion, good for bad, and it is a disgrace to even think about this!

I agree with Rabbi Mashash. Jews in space must observe Shabbat and festivals just as a Jew near the North or South Pole must observe Shabbat and festivals.

3) R. David Hayyim Sheloosh of Natanya says that a Jewish astronaut should count each orbit as a day and observe Shabbat every nine hours for ninety minutes. But festivals should be observed following the calendar of the earth since Jewish holidays follow the moon, and “moon days” are the same in space. On the other hand, he should pray the three daily services during every ninety-minute orbit.

One of the classic codes of Jewish law is the Arba’ah Turim or four columns, written by Rabbi Ya’akov ben Asher in the fourteenth century. There is an old Jewish proverb that a posek (halakhic authority) must also employ a fifth Tur: common sense. This suggestion does not fit that criterion. It is true that the Hassidim Rishonim (early pious ones) are described as having spent nine hours of every day in prayer (Berakhot 32b), but the general rule is that “the Torah was not given to the ministering angels” (Berakhot 25b; Kiddushin 54a). An astronaut who prays three times every ninety minutes and observes Shabbat every nine hours will indeed be exhausted, as in the joke above, and unable to perform any of his duties. Furthermore, the purpose of Shabbat is to rest after six 24-hour days of work and not every nine hours!

4) Rabbi Jonathan Romain, quoted in The Sunday Telegraph, says that “he should observe the same routine as you would on earth”, but he could be relieved of his Shabbat obligations because of Pikuah Nefesh (permission to desecrate Shabbat in order to save human life). But it is not clear from the article when he should observe Shabbat or pray.

5) I believe that Col. Ramon and future Jewish astronauts should observe Shabbat, festivals and daily prayer according to local time in Houston (or their home base). I say this for three reasons:

  1. Simple logic. All astronauts set their watches by Houston time. Otherwise they would spend all of their time in space changing the time on their watches as Rabbi Sheloosh would require.
  2. Secondly, we have a classic source for dealing with a similar situation. We have learned in Shabbat 69b: “A person lost in the desert who doesn’t know when it is Shabbat, counts six days and rests on the seventh”. In other words, when you are in a place where normal time divisions don’t exist, you arbitrarily adopt a method for observing Shabbat after six 24-hour days.
  3. Finally, we have a clear precedent for Shabbat in space, as already hinted above. Since the eighteenth century, rabbis have discussed how to observe Shabbat in “inner America”, Norway, Sweden, Alaska, Iceland and other areas where the sun does not rise or set for months on end. Polar days are unusually long; space days are unusually short – but the general problem is similar.

The rabbis who dealt with this dilemma, can be divided into four groups. The common denominator is that they all agree that you count six “normal” days of roughly 24 hours and the seventh is Shabbat.

  1. Rabbi Jacob Emden (1697-1776) – basing himself on the talmudic passage about the desert – said that a Jew who is near one of the poles and does not know when Shabbat occurs, counts six days of 24 hours and the seventh day is Shabbat. Rabbi Emden is quoted by Sha’arei Teshuvah to Orah Hayyim 344. Rabbi Horowitz and Rabbi Mashash agree with this approach.
  2. Rabbi Israel Lifshitz (1782-1860) says that if you have a watch, which shows the time at your point of origin, you observe Shabbat according to your point of origin. This follows the halakhic principle of following the customs of your point of origin if you intend to return there and if there is no local Jewish community (Rambam, Hilkhot Yom Tov 8:20 and Shulhan Arukh Orah Hayyim 468:4).
  3. Rabbi Menahem Mendel Schneerson, the Lubavitcher Rebbe (1902-1994) says that you should observe Shabbat according to places with the same longitude, but he gives no source for this approach.
  4. Rabbi Solomon Freehof, mentioned above, seems to think that you observe Shabbat according to the custom of the closest Jewish community, but he gives no source for this approach.

There are two modern rabbis who gave similar replies regarding Jews in space travel. R. Bezalel Stern says that an astronaut should follow earth time vis-a-vis prayer and Shabbat, though he doesn’t site any of the responsa about the poles. Rabbi Solomon Freehof makes a clear comparison between the poles and space travel, ruling according to his own approach to the poles (p. 246):

The answer to this problem [of Jews in space travel] must be the same as that which was given to the Soldiers in Iceland during the war (= World War Two)… that they must follow the hours of Boston, Massachusetts and the soldiers in Alaska must follow the hours in Portland, Oregon. After all, the watches in the capsule will keep earth time.

We agree with all of the rabbis who say that when near the Poles or in space, a Jew should observe days of roughly 24 hours. Rabbi Emden’s approach is not applicable because he was referring to a case where the traveler does not know the day or the time. The other two approaches have no specific source and are not applicable to Jews in space travel. Therefore, we agree with Rabbi Yisrael Lifshitz who says that the explorer – or in our case, the astronaut – should observe Shabbat according to his home base. This approach is based on halakhic sources and makes good sense since the non-Jewish astronauts also set their watches according to their home base. In other words, following R. Israel Lifshitz, a Jewish astronaut should pray, and observe Shabbat and festivals, according to Houston control, which is their home base. Indeed, according to the Jerusalem Post, Col. Ramon has resolved to keep time according to Central Standard Time, so as to be on the same clock as Houston.

We wish him and his fellow astronauts a successful journey: “Barukh atah b’vo’ekha, uvarukh atah b’tzetekha” – “Blessed shall you be in your comings, blessed shall you be in your goings” (Deut. 28:6)!


I) Space Travel

  1. R. Solomon Freehof, New Reform Responsa, HUC Press, 1980, pp. 243-246
  2. Jonathan Petre, The Sunday Telegraph, May 27, 2002
  3. R. Nahum Eliezer Rabinowitz, Hadarom, 15 (1962), p. 121, also quoted by R. Immanuel Jakobovits, Jewish Law Faces Modern Problems, New York, 1965, p. 121
  4. R. David Hayyim Sheloosh, Hemdah Genuzah, Vol. 1, Jerusalem, 1976, No. 2
  5. R. Bezalel Stern, B’tzel Hahokhmah, Vol. 4, Bnai Brak, 1982, No. 104
  6. Janine Zacharia, The Jerusalem Post, Friday, June 28, 2002, p. B5

II) Shabbat Near the North and South Poles

  1. R. Simhah Bamberger, Zekher Simhah, Frankfurt am Main, 1925, No. 30
  2. R. Refael Birdugo, Mishpatim Yesharim, Cracow, 1891, Vol. 1, No. 77
  3. R. Ya’akov Emden, Mor Uketzi’ah to Orah Hayyim 344, Jerusalem, 1996, also quoted in Sha’arei Teshuvah to Orah Hayyim 344
  4. R. Solomon Freehof, Responsa in War Time, New York, 1947, pp. 14-15
  5. R. Shlomo Goren, Torat Hashabbat V’hamoed, Jerusalem, 1982, pp. 106-127
  6. R. Pinhass Eliyahu Horowitz, Sefer Haberit, Bruna, 1797 (and reprints), Part I, Ma’amar 4, Chapter 11 (quoted briefly by Rabbi Bamberger)
  7. R. Yisrael Lifshitz, Tiferet Yisrael to Mishnah Berakhot, Chapter One, end, in “Boaz”, ed. Vilna, fol. 6a
  8. R. Yosef Mashash, Mayyim Hayyim, Fez, 1934, No. 111
  9. R. Hayyim Sheloosh, Hemdah Genuzah, Vol. 1, Jerusalem, 1976, No. 3
  10. R. Menahem Mendel Schneerson, Yagdil Torah, New York, 1981, No. 73

All four volumes of Rabbi Prof. David Golinkin’s Responsa In A Moment – Halakhic Responses to Contemporary Issues as well as other books by the author are available for purchase from the Schocken-JTS Press Bookstore.

Prof. David Golinkin is the President of the Schechter Institute of Jewish Studies in Jerusalem. Feel free to reprint this article in its entirety. If you wish to abbreviate the article, please contact Rabbi Golinkin at: The opinions expressed here are the author’s and in no way reflect an official policy of the Schechter Institute.

Image Credit: NASA

David Golinkin is President of The Schechter Institutes, Inc. and President Emeritus of the Schechter Institute of Jewish Studies. For twenty years he served as Chair of the Va’ad Halakhah (Law Committee) of the Rabbinical Assembly which gives halakhic guidance to the Masorti Movement in Israel. He is the founder and director of the Institute of Applied Halakhah at Schechter and also directs the Center for Women in Jewish Law. Rabbi Professor Golinkin made aliyah in 1972, earning a BA in Jewish History and two teaching certificates from The Hebrew University in Jerusalem. He received an MA in Rabbinics and a PhD in Talmud from the Jewish Theological Seminary of America where he was also ordained as Rabbi. For a complete bio click here.

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